毛白杨人工林灌溉管理理论及高效地下滴灌关键技术研究
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摘要
我国木材资源对外依存高达30%以上,“十二五”期间预计木材缺口2亿m3,木材安全问题严重,大力发展杨树速生丰产林是解决该问题的重要措施之一。然而,目前我国杨树人工林生产力低于世界平均水平,水分管理等集约经营水平低是其核心原因之一。本文以我国华北地区主要用材树种三倍体毛白杨(triploid Populus tomentosa)为研究对象,对其用材林灌溉管理理论和高效地下滴灌关键技术进行系统研究,旨在提高其林地水分管理水平,进而大幅提高林地生产力,为缓解我国木材进口压力提供一定的理论和技术支撑。同时,本研究还将为其它杨树品种人工林的水分管理提供一定的借鉴和指导。本文的主要结果和结论如下：
(1)采用地下滴灌技术(SDI),以距滴头10cm、地下20cm处的不同土壤水势(-25、-50、-75kPa)作为灌溉起始阈值对6、7年生毛白杨人工林进行灌溉。期间对林木树干液流和黎明前叶水势(ψpd)、土壤水势和含水率、气象因子及地下水位(GWL)等进行连续或定期监测。结果表明,与不灌溉(CK)相比,SDI使6、7年生林分生产力分别平均提高24%和28%,其中,-25kPa处理使6年生林分的生产力达到39.9m3·hm-2.a-1,较CK极显著提高44%(P<0.01)。-25kPa处理的生产力在林分6年生时分别较-50和-75kPa处理提高20%和31%(P<0.01),在7年生时分别提高13%和14%(P>0.05)。每年5-7月为毛白杨生长高峰期,期间的累积胸径生长量平均占全年的84%；此外,该时期GWL较低。每年8-10月,毛白杨生长极慢,GWL大幅回升,即使无灌溉情况下土壤水分有效性也较高。能在毛白杨速生期内(4-7月)大幅提高土壤含水率(20和50cm处分别平均提高35%和27%)、树干日平均液流速率(46%)和ψpd(41%)是SDI促进林木生长的重要机制。
(2)以充分灌溉下(-25kPa处理)的6、7年生毛白杨人工林为研究对象,采用热扩散技术(TDP)、微型蒸渗仪和WinSCANOPY冠层分析仪分别对林分的林木蒸腾、棵间土壤蒸发和叶面积指数(LAI)进行连续监测。结果表明,6、7年生林分的日平均蒸腾量(Tr)、蒸发量(Es)、蒸散量(ETa)分别为2.37和2.49mm·d-1,0.77和0.87mm·d-1,3.12和3.33mm·d-1,其年总Tr、Es、ET.分别为422和493mm、134和167mm、556和660mm。林地ETa在生长初期和末期主要由Es组成,比例为30%-97%；在生长中期主要由Tr组成,比例为70%-93%。提前一周进行第一次灌溉使7年生林分在展叶初期的冠层发展速度和液流速率较6年生林分明显提高,且使4月份的累积Tr提高147%。林分在5-7月的累积Tr平均可占全年的68%。毛白杨林分的基础作物系数(Kcb)和作物系数(Kc)与LAI间的关系均可用负指数函数描述,其决定系数R2分别为0.834和0.627。林分Kcb和Kc在生长前期(25d)分别为0.02-0.96和0.40-1.27,在生长中期(135d)分别为0.96和1.27,在生长后期(45d)分别为0.96-0.4和1.27-1.26。因此,每年5-7月为毛白杨主要耗水时期,4-7月为其林地水分调控关键期；拟合的Kcb(LAI)和Kc(LAI)函数可用于根据毛白杨林分的实测LAI估算其Kcb和Kc；构建的Kcb和Kc曲线与常规气象数据结合,可用于估算与试验地气候相似地区水分供应充足的成熟毛白杨纯林的蒸腾量和蒸散量。
(3)在5年生毛白杨人工林中采用土柱法获取2106个根样,并在不同林龄(4、5、7年生)和栽植密度(1250、1404、2500株·ha-1)林分中采用挖掘法追踪林木根系伸展范围并原位获得1株平均标准木(5年生)的整个粗根系统。结果表明,5年生毛白杨林分中,细根水平分布均匀,但随距树距离增加细根分布变浅：细跟垂直剖面呈不常见的“S”型分布模式；近一半(44%)的细根隶属0.2-0.5mm径阶。毛白杨在0-20cm表土以中分布有密集(25%)的细根,且将近三分之一(28%)的细根分布在100cm以下的深土层。毛白杨的平均细根直径在120cm以下土层中明显变粗(P<0.05)。毛白杨粗根的根长和生物量在水平向上分别主要分布在树干周围40和20cm区域,在垂向上分别主要集中在0-20和0-50cm的浅土层。毛白杨根幅可达冠幅的1.9倍：4、5和7年生林木根系的最大分布深度分别为2、2和2.7m。毛白杨1级侧根中,水平、斜生和垂直侧根的比例分别为79%、6%和15%。因此,5年生毛白杨人工林中已形成二态性根系系统；毛白杨的根系构型为具有垂直根的水平根型。
(4)在5年生毛白杨林分中于两株标准木周围布设试验小区,分别利用TDP、微型蒸渗仪和Trime-IPH对样树树干液流、土壤蒸发和土壤含水率动态进行连续4个月的监测,然后采用水量平衡法推导根系吸水剖面和吸水量。结果表明,在0-90cm土层山,0-20cm土层的根系吸水贡献率达到58%,意味着表层根系在浅土层(<90cm)中起主要吸水作用。毛白杨平均蒸腾耗水的57%来自深土层(>90cm)意味着深层根系对成熟毛白杨人工林的水分关系有显著贡献。表土层水分有效性增加时,根系吸水主要集中在表土层；降低时,深层根系的吸水贡献率会逐渐增加。土壤剖面水分条件异质性较高时,根系吸水主要集中在细根密度与水分有效性均较高的区域；土壤剖面水分分布均匀且不存在水分胁迫时,根系吸水分布与细根分布最为一致。因此,毛白杨根系吸水模式受细根分布影响,但会随土壤水分有效性分布的变化而变化。
(5)利用HYDRUS-1D和HYDRUS-2D/3D分别对自然降雨(NC)(CK处理)和SDI(-25kPa处理)下林地一维和二维土壤水分动态进行模拟,并用土壤水分实测数据进行验证,之后利用HYDRUS对连续两个生长季内SDI和NC下林地土壤水分有效性进行模拟。结果表明,HYDURS-1D模拟结果的均方根误差(RMSE)和相对平均绝对误差(RMAE)分别为0.004-0.060cm3.cm-3和0.7%-13.7%。HYDRUS-2D/3D的模拟结果,在不同土层的平均RMSE和RMAE分别为0.005-0.038cm3·cm-3和0.9%-9.7%；在滴头周围二维空间内的平均RMSE和RMAE分别为0.032cm3·cm-3和8.6%。SDI对土壤水分的影响主要局限于0-90cm土层。不同土层的土壤水分有效性(rθ)与林木生长间均有极显著相关关系(P<0.001),但随深度的增加,rθ对林木生长差异的解释程度逐渐下降。当根区(0-150cm土层)的rθ高于90%时,林木生长不会受到抑制。土壤水分对毛白杨生长的作用程度与土壤中的碱解氮、有机质含量和细根组织氮浓度间存在正相关关系(P<0.01),与细根平均直径间存在负相关关系(P<0.05),与速效磷含量、细根根长密度和比根长间无相关关系(P>0.05)。因此,HYDURS模型可很好地模拟NC(同漫灌)和SDI下毛白杨人工林的一维和二维土壤水分动态,并可帮助预测不同灌溉措施对毛白杨生长的影响；与NC处理相比,SDI促进林木生长的主要原因之一是其能大幅提高0-90土层的rθ；建立rθ与林木生长间的定量关系时,应考虑不同土层中rθ对林木生长影响的差异性。
(6)综上,在对与试验地环境相似地区的毛白杨人工林进行灌溉时：①可将距滴头10cm、地下20cm处的土壤水势达到-25kPa作为SDI的灌溉起始阈值；②利用本文构建的(基础)作物系数曲线和常规气象数据可估算生长季内林分的耗水量,从而帮助确定灌水量；③应于4-7月灌溉,8-10月可不灌溉；④应在对GWL定期监测的基础上制定灌溉制度；⑤灌溉水应主要供给并维持到0-40cm的浅土层,也应主要供给到树干周围1m区域内,以及土壤中碱解氮和有机质含量较高的区域；⑥可利用HYDRUS帮助制定灌溉管理策略；⑦若使整个根区的rθ保持在90%以上则林木生长不会受到抑制。
(7)本研究得出的结论均是基于成熟毛白杨人工林的,因此有一定局限性。下步应对毛白杨幼林开展类似研究以补允和优化本研究的结论,从而使其在毛白杨人工林的整个轮伐期内均适用。
At present, in China, more than30%of the domestically consumed timber are imported from abroad, and the predicted total timber shortage will reach200million m3during the '12th five year' period. Thus, the problem of timber security is very serious in China. One important solution to this problem is to vigorously develop fast-growing and high-yield poplar plantations. However, at present, the average productivity of poplar plantations in China is still below the global average level, which can be mainly attributed to its inefficient intensive silvicultural practices such as water management. In this research, the theories of irrigation management and key techniques of high efficient subsurface drip irrigation (SDI) were investigated for plantations of triploid Populus tomentosa, which is an important tree species for timber production in the North China Plain. The objective of this study was to improve the water management efficiency in P.tomentosa plantations, subsequently increasing their productivities and helping to ease the pressure of timber importation in China. Meanwhile, this study will also provide specific guidelines for water management in plantations of other poplar species. The main results and conclusions of this research are listed below:
(1) Subsurface drip irrigation (SDI) was applied in the6-and7-year-old P.tomentosa plantations. The SDI was initiated when the soil water potential (ψs) at20cm depth and10cm distance from a drip emitter reached-25,-50, and-75kPa, respectively. Trunk sap flow rate, pre-dawn leaf water potential (ψpd),ψs, soil water content, meteorological factors, and groundwater level (GWL) were monitored continuously or measured in selected periods. Results showed that relative to non-irrigation treatment (CK), SDI on average increased annual volume growth of the6-and7-year-old plantations by24%and28%. Annual volume growth of the6-year-old plantation following the-25kPa treatment reached39.9m3·hm-2·a-1, which was44%higher than the CK treatment (P<0.01). Relative to the-50and-75kPa treatments, annual volume growth in the-25kPa treatment was20%and31%higher (P<0.01) in the6-year-old plantation, and13%and14%higher (P>0.05) in the7-year-old plantation, respectively. The fast growing period of P.tomentosa was from May to July, during which time the cumulative DBH (diameter at breast height) increment accounted for84%of the total year increment and the GWL was very deep. From August to October every year, the growth rate of P.tomentosa was very slow, the GWL was relatively high, and the soil water availability was high even though there was no water recharge from irrigation. Relative to CK during the fast growing period (April-July) of P.tomentosa, SDI increased the soil water content at20and50cm depth by35%and27%, respectively;increased average daily trunk sap flow rate and ψpd by46%and41%, respectively. These are the mechanisms by which SDI significantly improves P.tomentosa tree growth.
(2)In the6-and7-year-old P.tomentosa plantations under full irrigation condition (i.e.-25kPa treatment), tree transpiration (Tr), soil evaporation (Es), and leal area index (LAI) were measured consecutively using thermal dissipation technique (TDP), micro-lysimeter (ML), and WinSCANOPY canopy analyser instrument, respectively. Results showed that, for the6-and7-year-old P.tomentosa plantations, the daily Tr, Es, and evapotranspiration (ETa) were2.37and2.49mnrd"1,0.77and0.87mm·d-1, and3.12and3.33mm·d-1, respectively; the whole year Tr, Es, and ETa were422and493mm,134and167mm, and556and660mm, respectively. In the initial and final growing period, Es was the dominant component and accounted for about30%-97%of ETa, Whereas, in the middle growing period, Tr became significant, accounting for about70%-93%of ETa. Relative to the6-year-old plantations, initiating the first irrigation one week earlier in the7-year-old plantations resulted in obviously faster canopy development and higher sap flow rate in initial leaf expansion period, and147%higher cumulative Tr in April. On average, cumulative T, between May and Junly accounted for68%of the whole year value. Relationship between Kcb and LAI could be simulated by a negative exponential function (R2=0.834), and the same for relationship between Kc and LAI (R2=0.627). The Kcb and Kc of P.tomentosa plantations in initial growing period (25d) were0.02-0.96and0.04-1.27, respectively; in middle growing period (135d) were0.96and1.27, respectively; and in final growing period (45d) were0.96-0.4and1.27-1.26, respectively. Therefore, every year, from May to July was the main water use period of P.tomentosa, and the key water management period for P.tomentosa plantations was from April to July. The fitted functions of Kcb(LAI) and Kc(LAI) could be used to predict Kcb and Kc of P.tomentosa plantations with the measured LAI. For mature pure P.tomentosa plantations in regions similar to our experimental site, their Tr, and ETa could be predicted by using our constructed Kcb>and Kc curves and commonly availabile meteorological data.
(3)2106root samples were collected in a5-year-old P.tomentosa plantation using soil coring method. Dry dig method was used to trace the root spread in plantaions with different ages (4-,5-, and7-year-old) and planting densities (1250,1404, and2500tree·ha-1), and to get the whole coarse root system of one5-year-old tree with average size. Resultes showed that, in the5-year-old P.tomentosa plantation, lateral root distribution was even, but root distribution tended to be shallower with increasing distance from tree trunk. In contrast, the vertical root profile showed an unusual pattern (nearly an 'S' shape). Nearly half (44%) of line roots corresponed to0.2-0.5mm diameter. Dense fine roots (25%) occurred in surface soil (0-20cm) and nearly one third (28%) of total line roots occurred below100cm depth. Mean line root diameter was significantly larger (P<0.05) below120cm. The main lateral distribution areas of coarse root length and biomass were within40and20cm distance from tree trunk, respectively, whereas their main vertical distribution soil layers were0-20and0-50cm depth, respectively. Root spread of P.tomentosa was1.9times as high as its canopy spread. The maximum rooting depth of4-,5-,and7-year-old trees were2,2, and2.7in, respectively.79%,6%, and15%of the 1-order lateral roots were horizontal, oblique, and vertical lateral roots, respectively. Thus, a dimorphic root system had developed in the5-year-old P.tomentosa plantation. The form of P.tomentosa root system was horizontal type with vertical roots.
(4) Two sample trees with average size were seclected from the5-year-old P.tomentosa plantation, and an experimental plot was established around each of them. Tranpiration of the sample trees, and soil evaporation and soil water content within the experimental plots were measured concurrently for four months using TDP, ML, and Trime-IPH, respectively. Then, soil water balance method was used to deduce the root water uptake (RWP) rate and pattern. Results showed that RWP in the0-20cm layer contributed58%of that within the0-90cm soil layer, suggesting surface roots played the major water uptake role in shallow soil (<90cm). On average, P.tomentosa extracted57%of transpired water from deep soil (>90cm), implying deep roots can contribute significantly to the water relations of mature P.tomentosa plantations. When the soil water availability increased in surface soil, the RWP mainly happened in surface soil. The water uptake contribution of deep roots increased when the water availability in surface soil decreased. When water condtion of the soil profile was highly heterogeneous, RWP mainly occurred in zones with both high fine roots density and high water availability. However, RWP pattern was in good agreement with the fine roots distribution when the soil water distribution was even and there was no water stress. Consequently, the RWP pattern of P.tomentosa was primarily determined by the fine root distribution, but would vary with the soil water availability distribution.
(5) HYDRUS-1D and HYDRUS-2D/3D were used to simulate one dimentional soil water dynamics under natural rainfall condition (NC)(i.e. CK treatment) and two dimentional soil water dynamics under SDI (-25kPa), respectively. Performace of these models were validated using measured soil water content data of two years. Then, HYDRUS models were used to simulate soil water availability dynamics in P.tomentosa plantations under NC and SDI for two growing seasons. Results showed that the root mean square error (RMSE) and relatively mean absolute error (RMAE) of the HYDRUS-1D simulation results were0.004-0.060cm3·cm-3and0.7%-13.7%, respectively. As to the simulation results of HYDRUS-2D/3D, the average RMSE and RMAE in different soil layers were0.005-0.038cm3·cm-3and0.9%-9.7%, respectively, and the average RMSE and RMAE within the domain around the dripper were0.032cm3·cm3and8.6%, respectively. The influence of SDI on soil water content was mainly limited to0-90cm soil.Soil water availability (r0) in all soil layers were significantly correlated with the fractional ABH (area at breast height) growth rate (P<0.001). However, the difference in tree growth that could be explained by ro decreased with increasing soil depth.Tree growth would not be limited when the roof root zone (0-150cm soil layer) was kept above90%.The effect of soil water on tree growth was positively correlated with the availabile nitrogen and organic matter content of soil and the tissue nitrogen content of fine roots (P<0.01), was negatively correlated with the mean fine root diameter (P<0.05), and was not correlated with the soil availabile phosphorus content and the root length density and specific root length of fine roots (P>0.05). Consequently, HYDRUS model can be used to simulate one and two dimentional soil water dynamics in P.tomentosa plantations under NC (similar to flood irrigation) and SDI, respectively, and can also be used to predict the influence of different irrigation treatments on the growth of P.tomentosa plantations. Relative to the NC treatment, one of the reasons that SDI could increase tree growth was that it could greatly increase the r0of0-90cm soil. The difference in influence of min different soil layers on tree growth should be considered when establishing the quantitative relationship between r0and tree growth rate.
(6) In conclusion, when apply irrigation in P.tomentosa plantations in regions similar to our experimental site:①ψ of-25kPa at20cm depth and10cm distance from a drip emitter can be used as the irrigation threshold of SDI;②the constructed Kcb, and Kc curves and commonly meteorological data can be used to estimate the water use of P.tomentosa plantations, subsequently helping to determine the irrigation amount;③irrigation should be applied between April and July, and terminated between August and October;④irrigation schedules should be devised based on periodic measurement of the depth to water table;⑤irrigation water should be mainly provided to and maintained in the surface40cm soil, the zone within1m from the tree, and the soil zone with higher availabile nitrogen and organic matter content;⑥HYDRUS can be used to design irrigation management strategies;⑦tree growth will not be limited when the r0of root zone is kept above90%.
(7) As this research was conducted in maure P.tomentosa plantations, the conclusions will inevitably have limitations. Thus, similar researches should also be conducted in young P.tomentosa plantations to supplement and optimize our conclusions, so that they can be applied in the whole rotation of P.tomentosa.
(1)采用地下滴灌技术(SDI),以距滴头10cm、地下20cm处的不同土壤水势(-25、-50、-75kPa)作为灌溉起始阈值对6、7年生毛白杨人工林进行灌溉。期间对林木树干液流和黎明前叶水势(ψpd)、土壤水势和含水率、气象因子及地下水位(GWL)等进行连续或定期监测。结果表明,与不灌溉(CK)相比,SDI使6、7年生林分生产力分别平均提高24%和28%,其中,-25kPa处理使6年生林分的生产力达到39.9m3·hm-2.a-1,较CK极显著提高44%(P<0.01)。-25kPa处理的生产力在林分6年生时分别较-50和-75kPa处理提高20%和31%(P<0.01),在7年生时分别提高13%和14%(P>0.05)。每年5-7月为毛白杨生长高峰期,期间的累积胸径生长量平均占全年的84%；此外,该时期GWL较低。每年8-10月,毛白杨生长极慢,GWL大幅回升,即使无灌溉情况下土壤水分有效性也较高。能在毛白杨速生期内(4-7月)大幅提高土壤含水率(20和50cm处分别平均提高35%和27%)、树干日平均液流速率(46%)和ψpd(41%)是SDI促进林木生长的重要机制。
(2)以充分灌溉下(-25kPa处理)的6、7年生毛白杨人工林为研究对象,采用热扩散技术(TDP)、微型蒸渗仪和WinSCANOPY冠层分析仪分别对林分的林木蒸腾、棵间土壤蒸发和叶面积指数(LAI)进行连续监测。结果表明,6、7年生林分的日平均蒸腾量(Tr)、蒸发量(Es)、蒸散量(ETa)分别为2.37和2.49mm·d-1,0.77和0.87mm·d-1,3.12和3.33mm·d-1,其年总Tr、Es、ET.分别为422和493mm、134和167mm、556和660mm。林地ETa在生长初期和末期主要由Es组成,比例为30%-97%；在生长中期主要由Tr组成,比例为70%-93%。提前一周进行第一次灌溉使7年生林分在展叶初期的冠层发展速度和液流速率较6年生林分明显提高,且使4月份的累积Tr提高147%。林分在5-7月的累积Tr平均可占全年的68%。毛白杨林分的基础作物系数(Kcb)和作物系数(Kc)与LAI间的关系均可用负指数函数描述,其决定系数R2分别为0.834和0.627。林分Kcb和Kc在生长前期(25d)分别为0.02-0.96和0.40-1.27,在生长中期(135d)分别为0.96和1.27,在生长后期(45d)分别为0.96-0.4和1.27-1.26。因此,每年5-7月为毛白杨主要耗水时期,4-7月为其林地水分调控关键期；拟合的Kcb(LAI)和Kc(LAI)函数可用于根据毛白杨林分的实测LAI估算其Kcb和Kc；构建的Kcb和Kc曲线与常规气象数据结合,可用于估算与试验地气候相似地区水分供应充足的成熟毛白杨纯林的蒸腾量和蒸散量。
(3)在5年生毛白杨人工林中采用土柱法获取2106个根样,并在不同林龄(4、5、7年生)和栽植密度(1250、1404、2500株·ha-1)林分中采用挖掘法追踪林木根系伸展范围并原位获得1株平均标准木(5年生)的整个粗根系统。结果表明,5年生毛白杨林分中,细根水平分布均匀,但随距树距离增加细根分布变浅：细跟垂直剖面呈不常见的“S”型分布模式；近一半(44%)的细根隶属0.2-0.5mm径阶。毛白杨在0-20cm表土以中分布有密集(25%)的细根,且将近三分之一(28%)的细根分布在100cm以下的深土层。毛白杨的平均细根直径在120cm以下土层中明显变粗(P<0.05)。毛白杨粗根的根长和生物量在水平向上分别主要分布在树干周围40和20cm区域,在垂向上分别主要集中在0-20和0-50cm的浅土层。毛白杨根幅可达冠幅的1.9倍：4、5和7年生林木根系的最大分布深度分别为2、2和2.7m。毛白杨1级侧根中,水平、斜生和垂直侧根的比例分别为79%、6%和15%。因此,5年生毛白杨人工林中已形成二态性根系系统；毛白杨的根系构型为具有垂直根的水平根型。
(4)在5年生毛白杨林分中于两株标准木周围布设试验小区,分别利用TDP、微型蒸渗仪和Trime-IPH对样树树干液流、土壤蒸发和土壤含水率动态进行连续4个月的监测,然后采用水量平衡法推导根系吸水剖面和吸水量。结果表明,在0-90cm土层山,0-20cm土层的根系吸水贡献率达到58%,意味着表层根系在浅土层(<90cm)中起主要吸水作用。毛白杨平均蒸腾耗水的57%来自深土层(>90cm)意味着深层根系对成熟毛白杨人工林的水分关系有显著贡献。表土层水分有效性增加时,根系吸水主要集中在表土层；降低时,深层根系的吸水贡献率会逐渐增加。土壤剖面水分条件异质性较高时,根系吸水主要集中在细根密度与水分有效性均较高的区域；土壤剖面水分分布均匀且不存在水分胁迫时,根系吸水分布与细根分布最为一致。因此,毛白杨根系吸水模式受细根分布影响,但会随土壤水分有效性分布的变化而变化。
(5)利用HYDRUS-1D和HYDRUS-2D/3D分别对自然降雨(NC)(CK处理)和SDI(-25kPa处理)下林地一维和二维土壤水分动态进行模拟,并用土壤水分实测数据进行验证,之后利用HYDRUS对连续两个生长季内SDI和NC下林地土壤水分有效性进行模拟。结果表明,HYDURS-1D模拟结果的均方根误差(RMSE)和相对平均绝对误差(RMAE)分别为0.004-0.060cm3.cm-3和0.7%-13.7%。HYDRUS-2D/3D的模拟结果,在不同土层的平均RMSE和RMAE分别为0.005-0.038cm3·cm-3和0.9%-9.7%；在滴头周围二维空间内的平均RMSE和RMAE分别为0.032cm3·cm-3和8.6%。SDI对土壤水分的影响主要局限于0-90cm土层。不同土层的土壤水分有效性(rθ)与林木生长间均有极显著相关关系(P<0.001),但随深度的增加,rθ对林木生长差异的解释程度逐渐下降。当根区(0-150cm土层)的rθ高于90%时,林木生长不会受到抑制。土壤水分对毛白杨生长的作用程度与土壤中的碱解氮、有机质含量和细根组织氮浓度间存在正相关关系(P<0.01),与细根平均直径间存在负相关关系(P<0.05),与速效磷含量、细根根长密度和比根长间无相关关系(P>0.05)。因此,HYDURS模型可很好地模拟NC(同漫灌)和SDI下毛白杨人工林的一维和二维土壤水分动态,并可帮助预测不同灌溉措施对毛白杨生长的影响；与NC处理相比,SDI促进林木生长的主要原因之一是其能大幅提高0-90土层的rθ；建立rθ与林木生长间的定量关系时,应考虑不同土层中rθ对林木生长影响的差异性。
(6)综上,在对与试验地环境相似地区的毛白杨人工林进行灌溉时：①可将距滴头10cm、地下20cm处的土壤水势达到-25kPa作为SDI的灌溉起始阈值；②利用本文构建的(基础)作物系数曲线和常规气象数据可估算生长季内林分的耗水量,从而帮助确定灌水量；③应于4-7月灌溉,8-10月可不灌溉；④应在对GWL定期监测的基础上制定灌溉制度；⑤灌溉水应主要供给并维持到0-40cm的浅土层,也应主要供给到树干周围1m区域内,以及土壤中碱解氮和有机质含量较高的区域；⑥可利用HYDRUS帮助制定灌溉管理策略；⑦若使整个根区的rθ保持在90%以上则林木生长不会受到抑制。
(7)本研究得出的结论均是基于成熟毛白杨人工林的,因此有一定局限性。下步应对毛白杨幼林开展类似研究以补允和优化本研究的结论,从而使其在毛白杨人工林的整个轮伐期内均适用。
At present, in China, more than30%of the domestically consumed timber are imported from abroad, and the predicted total timber shortage will reach200million m3during the '12th five year' period. Thus, the problem of timber security is very serious in China. One important solution to this problem is to vigorously develop fast-growing and high-yield poplar plantations. However, at present, the average productivity of poplar plantations in China is still below the global average level, which can be mainly attributed to its inefficient intensive silvicultural practices such as water management. In this research, the theories of irrigation management and key techniques of high efficient subsurface drip irrigation (SDI) were investigated for plantations of triploid Populus tomentosa, which is an important tree species for timber production in the North China Plain. The objective of this study was to improve the water management efficiency in P.tomentosa plantations, subsequently increasing their productivities and helping to ease the pressure of timber importation in China. Meanwhile, this study will also provide specific guidelines for water management in plantations of other poplar species. The main results and conclusions of this research are listed below:
(1) Subsurface drip irrigation (SDI) was applied in the6-and7-year-old P.tomentosa plantations. The SDI was initiated when the soil water potential (ψs) at20cm depth and10cm distance from a drip emitter reached-25,-50, and-75kPa, respectively. Trunk sap flow rate, pre-dawn leaf water potential (ψpd),ψs, soil water content, meteorological factors, and groundwater level (GWL) were monitored continuously or measured in selected periods. Results showed that relative to non-irrigation treatment (CK), SDI on average increased annual volume growth of the6-and7-year-old plantations by24%and28%. Annual volume growth of the6-year-old plantation following the-25kPa treatment reached39.9m3·hm-2·a-1, which was44%higher than the CK treatment (P<0.01). Relative to the-50and-75kPa treatments, annual volume growth in the-25kPa treatment was20%and31%higher (P<0.01) in the6-year-old plantation, and13%and14%higher (P>0.05) in the7-year-old plantation, respectively. The fast growing period of P.tomentosa was from May to July, during which time the cumulative DBH (diameter at breast height) increment accounted for84%of the total year increment and the GWL was very deep. From August to October every year, the growth rate of P.tomentosa was very slow, the GWL was relatively high, and the soil water availability was high even though there was no water recharge from irrigation. Relative to CK during the fast growing period (April-July) of P.tomentosa, SDI increased the soil water content at20and50cm depth by35%and27%, respectively;increased average daily trunk sap flow rate and ψpd by46%and41%, respectively. These are the mechanisms by which SDI significantly improves P.tomentosa tree growth.
(2)In the6-and7-year-old P.tomentosa plantations under full irrigation condition (i.e.-25kPa treatment), tree transpiration (Tr), soil evaporation (Es), and leal area index (LAI) were measured consecutively using thermal dissipation technique (TDP), micro-lysimeter (ML), and WinSCANOPY canopy analyser instrument, respectively. Results showed that, for the6-and7-year-old P.tomentosa plantations, the daily Tr, Es, and evapotranspiration (ETa) were2.37and2.49mnrd"1,0.77and0.87mm·d-1, and3.12and3.33mm·d-1, respectively; the whole year Tr, Es, and ETa were422and493mm,134and167mm, and556and660mm, respectively. In the initial and final growing period, Es was the dominant component and accounted for about30%-97%of ETa, Whereas, in the middle growing period, Tr became significant, accounting for about70%-93%of ETa. Relative to the6-year-old plantations, initiating the first irrigation one week earlier in the7-year-old plantations resulted in obviously faster canopy development and higher sap flow rate in initial leaf expansion period, and147%higher cumulative Tr in April. On average, cumulative T, between May and Junly accounted for68%of the whole year value. Relationship between Kcb and LAI could be simulated by a negative exponential function (R2=0.834), and the same for relationship between Kc and LAI (R2=0.627). The Kcb and Kc of P.tomentosa plantations in initial growing period (25d) were0.02-0.96and0.04-1.27, respectively; in middle growing period (135d) were0.96and1.27, respectively; and in final growing period (45d) were0.96-0.4and1.27-1.26, respectively. Therefore, every year, from May to July was the main water use period of P.tomentosa, and the key water management period for P.tomentosa plantations was from April to July. The fitted functions of Kcb(LAI) and Kc(LAI) could be used to predict Kcb and Kc of P.tomentosa plantations with the measured LAI. For mature pure P.tomentosa plantations in regions similar to our experimental site, their Tr, and ETa could be predicted by using our constructed Kcb>and Kc curves and commonly availabile meteorological data.
(3)2106root samples were collected in a5-year-old P.tomentosa plantation using soil coring method. Dry dig method was used to trace the root spread in plantaions with different ages (4-,5-, and7-year-old) and planting densities (1250,1404, and2500tree·ha-1), and to get the whole coarse root system of one5-year-old tree with average size. Resultes showed that, in the5-year-old P.tomentosa plantation, lateral root distribution was even, but root distribution tended to be shallower with increasing distance from tree trunk. In contrast, the vertical root profile showed an unusual pattern (nearly an 'S' shape). Nearly half (44%) of line roots corresponed to0.2-0.5mm diameter. Dense fine roots (25%) occurred in surface soil (0-20cm) and nearly one third (28%) of total line roots occurred below100cm depth. Mean line root diameter was significantly larger (P<0.05) below120cm. The main lateral distribution areas of coarse root length and biomass were within40and20cm distance from tree trunk, respectively, whereas their main vertical distribution soil layers were0-20and0-50cm depth, respectively. Root spread of P.tomentosa was1.9times as high as its canopy spread. The maximum rooting depth of4-,5-,and7-year-old trees were2,2, and2.7in, respectively.79%,6%, and15%of the 1-order lateral roots were horizontal, oblique, and vertical lateral roots, respectively. Thus, a dimorphic root system had developed in the5-year-old P.tomentosa plantation. The form of P.tomentosa root system was horizontal type with vertical roots.
(4) Two sample trees with average size were seclected from the5-year-old P.tomentosa plantation, and an experimental plot was established around each of them. Tranpiration of the sample trees, and soil evaporation and soil water content within the experimental plots were measured concurrently for four months using TDP, ML, and Trime-IPH, respectively. Then, soil water balance method was used to deduce the root water uptake (RWP) rate and pattern. Results showed that RWP in the0-20cm layer contributed58%of that within the0-90cm soil layer, suggesting surface roots played the major water uptake role in shallow soil (<90cm). On average, P.tomentosa extracted57%of transpired water from deep soil (>90cm), implying deep roots can contribute significantly to the water relations of mature P.tomentosa plantations. When the soil water availability increased in surface soil, the RWP mainly happened in surface soil. The water uptake contribution of deep roots increased when the water availability in surface soil decreased. When water condtion of the soil profile was highly heterogeneous, RWP mainly occurred in zones with both high fine roots density and high water availability. However, RWP pattern was in good agreement with the fine roots distribution when the soil water distribution was even and there was no water stress. Consequently, the RWP pattern of P.tomentosa was primarily determined by the fine root distribution, but would vary with the soil water availability distribution.
(5) HYDRUS-1D and HYDRUS-2D/3D were used to simulate one dimentional soil water dynamics under natural rainfall condition (NC)(i.e. CK treatment) and two dimentional soil water dynamics under SDI (-25kPa), respectively. Performace of these models were validated using measured soil water content data of two years. Then, HYDRUS models were used to simulate soil water availability dynamics in P.tomentosa plantations under NC and SDI for two growing seasons. Results showed that the root mean square error (RMSE) and relatively mean absolute error (RMAE) of the HYDRUS-1D simulation results were0.004-0.060cm3·cm-3and0.7%-13.7%, respectively. As to the simulation results of HYDRUS-2D/3D, the average RMSE and RMAE in different soil layers were0.005-0.038cm3·cm-3and0.9%-9.7%, respectively, and the average RMSE and RMAE within the domain around the dripper were0.032cm3·cm3and8.6%, respectively. The influence of SDI on soil water content was mainly limited to0-90cm soil.Soil water availability (r0) in all soil layers were significantly correlated with the fractional ABH (area at breast height) growth rate (P<0.001). However, the difference in tree growth that could be explained by ro decreased with increasing soil depth.Tree growth would not be limited when the roof root zone (0-150cm soil layer) was kept above90%.The effect of soil water on tree growth was positively correlated with the availabile nitrogen and organic matter content of soil and the tissue nitrogen content of fine roots (P<0.01), was negatively correlated with the mean fine root diameter (P<0.05), and was not correlated with the soil availabile phosphorus content and the root length density and specific root length of fine roots (P>0.05). Consequently, HYDRUS model can be used to simulate one and two dimentional soil water dynamics in P.tomentosa plantations under NC (similar to flood irrigation) and SDI, respectively, and can also be used to predict the influence of different irrigation treatments on the growth of P.tomentosa plantations. Relative to the NC treatment, one of the reasons that SDI could increase tree growth was that it could greatly increase the r0of0-90cm soil. The difference in influence of min different soil layers on tree growth should be considered when establishing the quantitative relationship between r0and tree growth rate.
(6) In conclusion, when apply irrigation in P.tomentosa plantations in regions similar to our experimental site:①ψ of-25kPa at20cm depth and10cm distance from a drip emitter can be used as the irrigation threshold of SDI;②the constructed Kcb, and Kc curves and commonly meteorological data can be used to estimate the water use of P.tomentosa plantations, subsequently helping to determine the irrigation amount;③irrigation should be applied between April and July, and terminated between August and October;④irrigation schedules should be devised based on periodic measurement of the depth to water table;⑤irrigation water should be mainly provided to and maintained in the surface40cm soil, the zone within1m from the tree, and the soil zone with higher availabile nitrogen and organic matter content;⑥HYDRUS can be used to design irrigation management strategies;⑦tree growth will not be limited when the r0of root zone is kept above90%.
(7) As this research was conducted in maure P.tomentosa plantations, the conclusions will inevitably have limitations. Thus, similar researches should also be conducted in young P.tomentosa plantations to supplement and optimize our conclusions, so that they can be applied in the whole rotation of P.tomentosa.
引文
[1]陈兰岭,辛忠智,李宝琪,等.干旱地区杨树速生产林灌水与林木生长的关系.林业科学研究,1991,4(5)：447-452.
[2]陈亚新,康绍忠.非充分灌溉原理.北京：水利电力出版社,1995.
[3]程先军,许迪.地下滴灌土壤水运动和溶质运移的数学模型及验证.农业工程学报,2001,17(6)：1-4.
[4]成向荣,黄明斌,邵明安.沙地小叶杨和柠条细根分布与土壤水分消耗的关系.中国水土保持科学,2008,6(5)：77-83.
[5]党宏忠,周泽福,张劲松,等.柠条主根液流测定中ΔTmax与气象因子间的关系及时间步长的确定.生态学报,2010,30(3)：0587-0593.
[6]董文怡.毛白杨苗期水肥耦合效应研究.北京：北京林业大学,2011.
[7]方晓娟,李吉跃,聂立水,等.毛白杨杂种无性系生长及耗水特性研究.西北林学院学报,2010,25(5)：12-17.
[8]冯起,司建华,李建林,等.胡杨根系分布特征与根系吸水模型建立.地球科学进展,2008,23(7)：765-772.
[9]国家林业局森林资源管理司.全国森林资源统计—第七次全国森林资源清查.北京：国家林业局,2010.
[10]贺康宁.林地土壤水分运动的数学模型.北京林业大学学报,1992,14(1)：77-86.
[11]贾黎明,韦艳葵,李延安等.地下滴灌条件下杨树速生丰产林生长与光合特性.林业科学,2004,40(2)：61-67.
[12]贾黎明,刘诗琦,祝令辉,等.我国杨树林的碳储量和碳密度.南京林业大学学报(自然科学版),2013,37(2)：1—7.
[13]康向阳,朱之悌.三倍体毛白杨在我国纸浆林生产中的地位与作用.北京林业大学学报,2002,24(增刊)：51-56.
[14]米剑斌,工全九.土壤水分特征曲线模型比较分析.水土保持学报,2003,17(1)：137-140.
[15]雷志栋,杨诗秀.非饱和土壤水一维流动的数值模拟.土壤学报,1982,19(2)：141-152.
[16]李道西,罗金耀,彭世彰.地下滴灌土壤水分运动室内试验研究.灌溉排水学报,2004,4：26-28.
[17]李恩羊.渗灌条件下土壤水分运动的数学模拟.水利学报,1982,4：1-10.
[18]李久生,杨凤艳,栗岩峰.层状土壤质地对地下滴灌水氮气分布的影响.农业工程学报,2009,25(7)：25-31.
[19]刘晨峰,张志强,孙阁,等.基于涡度相关法和树干液流法评价杨树人工林生态系统蒸发散及其环境响应.植物生态学报,2009,33(4)：706-718.
[20]刘奉觉,郑世凯,臧道群.田间供水与杨树生长关系的研究.Ⅰ.供水处理对杨树生长、树体结构和叶量的影响.林业科学研究,1988a,1(2)：153-161.
[21]刘奉觉,郑世凯,臧道群.田间供水与杨树生长关系的研究.Ⅱ.田间供水、蒸腾耗水与材积产量的关系分析及林木蓄水量的估算.林业科学研究,1988b,1(3)：252-258.
[22]刘庆新,孟平.张劲松,等.基于侧柏液流的测定对Graniet原始公式系数进行校止.生态学报,2013,33(6)：1944-1951.
[23]刘新平,张铜会,何玉惠,等.科尔沁沙地三种常见乔木根—土届面水分再分布探讨.生态环境学报,2009,18(6)：2360-2365.
[24]刘玉春,李久生.毛管埋深和层状质地对番茄滴灌水氮利用效率的影响.农业工程学报,2009a,25(6)：7-12.
[25]刘玉春,李久生.毛管埋深和土壤层状质地对地下滴灌番茄根区水氮动态和根系分布的影响.水利学报,2009b,40(7)：782-790.
[26]刘玉春,李久生.滴灌灌溉计划制定中毛管埋深对负压计布置方式的影响.农业工程学报,2010,26(4)：18-24.
[27]李广德.三倍体毛白杨速生纸浆林蒸腾耗水特性及灌溉制度研究.北京：北京林业大学,2010.
[28]李光永.地埋点源非饱和土壤水运动的数值模拟.水利学报,1996,(11)：47—56.
[29]李光永.微灌原理与研究紧张.//康绍忠.农业水土工程概论,2007：452-482.
[30]李久生,张建君,饶敏杰.滴灌施肥灌溉的水氮运移数学模拟及试验验证.水利学报,2005,36(8)：1-10.
[31]李贤伟,张健,陈文德,等.三倍体毛白杨—黑麦草复合模式细根和草根分布与生长特征.草业学报,2005,14(6)：73-78.
[32]罗毅,徐建新,李宝萍.地表下滴灌土壤水分运动数值模拟.华北水利水电学院学报,1995,16(2)：1-9.
[33]罗毅,于强,欧阳竹,唐登银,等.利用精确的田间实验资料对几个常用根系吸水模型的评价与改进.水利学报,2000,4：73-80.
[34]绿色新闻网.三倍体毛白杨推广课题通过验收2009.http://news.bjfu.edu.cn/jxky/25607.htm
[35]马晖,于卫平,黄利江,等.杨树速生丰产林的节水灌溉试验.林业科学研究,2004,17(增刊)：119-121.
[36]马履一.国内外土壤水分研究现状和进展.世界林业研究,1997,5：26-32.
[37]马履一.山坡林地开放渗透系中土壤水分物理—生态的立地研究.北京：北京林业大学,1995.
[38]马孝义,谢建波,康银红.重力式地下滴灌土壤水分运动规律的模拟研究.灌溉排水学报,2006,25(6)：5-10.
[39]马孝义.作物水分信息采集与精量控制用水技术.//康绍忠.农业水土工程概论,2007：358-389.
[40]马秀玲,陆光明,徐祝龄,等.农林复合系统中林带和作物的根系分布特征.中国农业大学学报,1997,2(1)：109-116.
[41]马玉敏,王迎,玄成龙,等.三倍体毛白杨无性系生长形状研究.山东林业科技,2005,5：11-14.
[42]孟平,张劲松,王鹤松,等.苹果树蒸腾规律及其与冠层微气象要素的关系.生态学报,2005,25(5)：1075-1081.
[43]潘成忠,上官周平.黄土区次降雨条件下林地径流和侵蚀产沙形成机制：以人工油松林和次生山杨林为例.应用生态学报,2005,16(9)：1579-1602.
[44]任忠秀,聂立水,张强,等.水氮耦合下毛白杨无性系材积生长规律及品种选择.中南林业科技大学学报,2011,31(8)：187-193.
[45]桑玉强,刘玉军,吴文良,等.毛乌素沙地新疆杨生长季节蒸腾耗水规律.东北林业大学学报,2008,36(9)：28-31,
[46]沈国舫.对发展我国速生丰产林有关问题的思考.世界林业研究1992,4：67-74.
[47]史册,范文波,朱红凯,等.不同灌水梯度下新疆杨耗水过程与灌溉制度初步研究.中国农村水利水电,2011,9：1—7.
[48]师伟,王政权,刘金梁,等.帽儿山天然次生林20个阔叶树种细根形态.植物生态学报,2008,32(6)：1217-1226.
[49]时新宁,张振文,黄支全.沙地防护林滴灌技术研究.林业科学研究,2004,17(增刊)：15-22.
[50]苏文锷,张冠宗.新疆十旱地区杨树的灌溉造林.八一农学院学报,1989,39：42-45.
[51]宋曰钦.三倍体毛白杨纸浆林地力维持技术理论及关键技术研究,北京：北京林业大学,2009.
[52]宋曰钦,翟明普,贾黎明,等.不同年龄三倍体毛白杨纸浆林生长期间细根变化规律.生态学杂志,2010,29(9)：1696--1702.
[53]宋子刚,周文权,王彦辉.毛白杨农田防护林带细根分布特征.林业资源管理,2009,6：96-101.
[54]孙鹏森.京北水源保护林格局及不同尺度树种耗水特性的研究.北京：北京林业大学,2000.
[55]孙守家,孟平,张劲松,等.华北石质山区核桃-绿豆复合系统氘同位素变化及其水分利用.生态学报,2010,30(14)：3717-3726
[56]孙兆地,聂立水,辛颖,等.水氮耦合效应对三倍体毛白杨林木生长状况的影响.土壤通报,2012,43(4)：896-902.
[57]田富强,胡和平.基于常微分方法求解器的Richards方程数值模型.清华大学学报(自然科学版),2007,47(6)：785-788.
[58]王葆芳,朱灵益.灌溉对群众杨生长条件的调控作用的研究.林业科学,1992,28(6)：555-560.
[59]王葆芳,杨晓晖,江泽平,等.干旱区杨树用材林土壤特性和林木生长对供水的响应.干旱区资源与环境,2006,20(6)：156-162.
[60]王力,邵明安,王全九.林地土壤水分运动研究综述.林业科学,2005,41(2)：147-153.
[61]王文全,贾渝彬,胥丽敏,等.毛白杨根系分布的研究.河北农业大学学报,1997,20(1)：24-29.
[62]王文全,贾玉彬,李惠卓等.毛白杨幼林灌溉效应及其特点分析.南京林业大学学报,2000,24(1)：17-22.
[63]王文全,李秀江,贾玉彬,等.沙地毛白杨速生丰产林节水灌溉的研究.河北农业大学学报,2001,24(1)：33-37.
[64]王展,周云成,虞娜,等.以分形理论估计棕壤水分特征曲线的可行性研究.沈阳农业大学学报,2005,36(5)：570-574.
[65]王振华,吕德生,温新明,等.地下滴灌对棉花生理性状及产量影响的研究.节水灌溉,2006,4：11—13.
[66]王政权,郭大力.根系生态学.植物生态学报,2008,32(6)：1213—1216.
[67]王治军,雒天峰.滴灌条件下侧柏林地根区土壤水分运动规律研究.干旱地区农业,2008,26(4)：13-16.
[68]卫星,刘颖,陈海波.黄波罗不同根序的解剖结构及其功能异质性.植物生态学报,2008,32(6)：1238-1247.
[69]韦艳葵,贾黎明,刑长山.滴灌在林业上应用的研究.世界林业研究,2003,16(4)：38-43.
[70]温远光,刘世荣.我国主要森林生态系统类型降雨截留规律的数量分布.林业科学,1995,31(4)：289-298.
[71]席本野,贾黎明,刘寅,等.宽窄行栽植模式下三倍体毛白杨休吸水根系的空间分布与模拟.浙 江林学院学报,2010,27(2)：259-265.
[72]席本野,贾黎明,王烨,等.地下滴灌条件下三倍体毛白杨根区土壤水分动态模拟.应用生态学报,2011,22(1)：21-28.
[73]席本野,王烨,贾黎明,司静,向地奎.宽窄行栽植模式下三倍体毛白杨根系分布特征及其与根系吸水的关系.生态学报,2011,31(1)：47-57.
[74]席本野,王烨,邸楠,等.地下滴灌下土壤水势对毛白杨纸浆林生长及生理特性的影响.生态学报,2012,32(17)：5318-5329.
[75]徐贵青,李彦.共生条件下三种荒木灌木的根系分布特征及其对降水的响应.生态学报,2009,29(1)：130--137.
[76]仵峰,彭贵方,吕谋超,等.地下滴灌条件下土壤水分运动模型.灌溉排水,1996,15(3)：24-29.
[77]向师庆,赵相华.北京主要造林树种的根系研究.北京林学院学报,1981,2：19-32.
[78]燕辉,刘广全,李红生.青杨人工林根系生物量、表面积和根长密度变化.应用生态学报,2010,21(11)：2763-2768.
[79]杨建伟,梁宗锁,韩蕊莲,等.不同干旱土壤条件下杨树的耗水规律及水分利用效率研究.植物生态学报,2004,28(5)：630--636.
[80]余伟莅,庞德胜,田永祯,等.不同灌溉处理杨树新品种生长量比较.内蒙古林业科技,2007,33(4)：1-3.
[81]张爱莉.最经济的灌水法—地下滴灌.灌溉排水,1995,14(1)：50-52.
[82]张广才,张振文,时新宁,等.滴灌在沙地防护林上应用的综合效益初步研究.林业科学研究,2004,17(增刊)：78-82.
[83]张明福.节水灌溉小管出流技术在杨树丰产林建设中的应用.林业技术,2007,6：12-13.
[84]张平冬,康向阳,赵光荣,等.三倍体毛白杨超短轮伐纸浆林生长量与密度关系研究.西北林学院学报,2009,24(4)：121-124.
[85]张思聪,惠士博,雷志栋,等.水平非饱和土壤水二维运动的准解析解.水利学报,1986,17(3)：54-60.
[86]张小由,康尔泗,司建华,等.黑河下游胡杨林耗水规律研究.干旱区资源与环境,2006,20(1)：195-197.
[87]张宇清,齐实,邹青,等.梯田埂坎杨树的根系分布研究.西北林学院学报,2002,17(2)：6-9.
[88]张振华,蔡焕杰,杨润亚等.滴灌入渗土壤水分分布的数值研究.水土保持研究,2004,11(3)：91-94.
[89]郑世锴.杨树丰产栽培.北京：金盾出版社,2006.
[90]周云城.地下滴灌土壤水分运动过程的数值解析与模拟.沈阳：沈阳农业大学,2005.
[91]朱强根,张焕朝,方升佐,等.苏北杨树人工林细根分布及其季节动态.林业科技开发,2008,22(3)：45-48.
[92]朱望先,王爱珍.杨树沟灌试验报告.新疆林业,1983,3：18-19.
[93]朱之悌,林惠斌,康向阳.毛白杨异源三倍体B301等无性系选育的研究.林业科学,1995,31(6)：499-505.
[94]Adiku S G K, Rose C W, Braddck R D, et al. On the simulation of root water extraction: examination of a minimum energy hypothesis. Soil Science,2000,165:226-236.
[95]Al Afas N, Marron N, Zavalloni C, et al. Growth and production of a short-rotation coppice culture of poplar-Ⅳ:fine root characteristics of five poplar clones.Biomass and Bioenergy, 2008, 32: 494-502.
[96]Allen S J, Hall R L, Rosier P T W. Transpiration by two poplar varieties grown as coppice for biomass production. Tree Physiology, 1999, 19:493-501.
[97]Anderson T M, Starmer W T, Thome M. Bimodal root diameter distributions in Serengeti grasses exhibit plasticity in response to defoliation and soil texture: implications for nitrogen uptake. Functional Ecology, 2007, 21: 50-60.
[98]Atkinson D. The distribution and effectiveness of the roots of tree crops. Horticultural Reviews, 1980,2:424-490.
[99]Bauerle T L, Smart D R, Bauerle W L, et al. Root foraging in response to heterogeneous soil moisture in two grapevines that differ in potential growth rate. New Phytologist, 2008, 179: 857-866.
[100]Block R M A, Van Rees K C J, Knight J D. A review of fine root dynamics in Populus plantations. Agroforestry Systems, 2006, 67: 73-84.
[101]Boast C W, Robertson TM. A 'micro-lysimeter' method for determining evaporation from bare soil: description and laboratory evaluation. Soil Science Society of America Journal, 1982, 46: 689-696.
[102]Brandt A, Bresler E, Diner N, et al. Infiltration from a trickle source: I. mathematical models. Soil Science Society of America Journal, 1971, 35(5): 675-682.
[103]Brooks R H, Corey A T. Properties of porous media affecting fluid flow. Journal of Irrigation and Drainage Division, Proceedings of the American Society of Civil Engineers, 1966, 92(IR2): 61-68.
[104]Bucks D A, Erie L J, French O F, Nakayama F S, Pew W D. Subsurface trickle irrigation management with multiple cropping. Transaction of ASAE, 1981,24: 1482-1489.
[105]Caldwell D S, Spurgeon W E, Manges H L. Frequency of irrigation for subsurface drip-irrigated corn. Transaction of the ASAE, 1994, 37(6): 1099-1103
[106]Caldwell M M, Dawson T E, Richards J H. Hydraulic lift: consequences of water efflux from the roots of plants. Oecologia, 1998, 113:151-161.
[107]Camp C R. Subsurface drip irrigation: a review. Transactions of the American Society of Agricultural Engineers, 1998, 41(5): 1353-1367.
[108]Caruso G, Rapoport H F, Gucci R. Long-term evaluation of yield components of young olive trees during the onset of fruit production under different irrigation regimes. Irrigation Science, 2013, 31(1): 37-47.
[109]Ceulemans R. Deraedt W. Production physiology and growth potential of poplars under short-rotation forestry culture. Forest Ecology and Management, 1999, 121: 9-23.
[110]Chisersson L. Biomass production of intensively grown poplar in the southernmost part of Sweden: Observations of characters, traits and growth potential. Biomass and Bioenergy, 2006, 30: 497-508.
[111]Clothier B E, Green S R. Rootzone processes and the efficient use of irrigation water. Agricultural Water Management, 1994,25: 1-12.
[112]Clothier B E, Green S R. Roots: the big movers of water and chemical in soil. Soil Science, 1997, 162:534-543.
[113]Coleman M. Spatial and temporal patterns of root distribution in developing stands of four woody crop species grown with drip irrigation and fertilization. Plant and Soil, 2007, 299: 195-213.
[114]Cook F J, Thorburn P J, Fitch P, et al. WetUp: a software tool to display approximate wetting patterns from drippers. Irrigation Science,2003,22(3):129-134.
[115]Cox G, Fischer D, Hart S C, et al. Nonresponse of native cottonwood trees to water additions during summer drought. Western North American Naturalist,2005,65(2):175-185.
[116]Coyle D R, Coleman M D. Forest production responses to irrigation and fertilization are not explained by shifts in allocation. Forest Ecology and Management,2005,208:137-152.
[117]Crockford R H, Richardson D P. Partioning of rainfall into throughfall, stemflow and interception:effect of forest type, ground cover and climate. Hydrological Processes,2000,14: 2903-2920.
[118]Daniel H. Introduction to Environmental Soil Physics. Elsevier Academic Press,2004.
[119]Dawson T E, Pate J S. Seasonal water uptake and movement in root systems of Australian phraeatophytic plants of dimorphic root morphology:a stable isotope investigation. Oecologia, 1996,107:13-20.
[120]de Medeiros G A, Arruda F B, Sakai E. Crop coefficient for irrigated beans derived using three reference evaporation methods. Agricultural and Forest Meteorology,2005,135:135-143.
[121]Dickmann D I, Nguyen P V, Pregitzer K S. Effects of irrigation and coppicing on above-ground growth, physiology, and fine-root dynamics of two field-grown hybrid poplar clones. Forest Ecology and Management,1996,80:163-174.
[122]Dlotra J, Munoz P. Simulation of nitrogen leaching from a fertigated crop rotation in a Mediterranean climate using the EU-Rotate_N and Hydrus-2D models. Agricultural Water Management,2010,97:277-285.
[123]Domenicano S, Coll L, Messier C, et al. Nitrogen forms affect root structure and water uptake in the hybrid poplar. New Forest,2011,42:347-362.
[124]Douglas G B, Mclvor I R, Potter J F, et al. Root distribution of poplar at varying densities on pastoral hill country. Plant and Soil,2010,333:147-161.
[125]Duchemin B, Hadria R, Erraki S, et al. Monitoring wheat phenology and irrigation in Cenral Morocco:on the use of realationships between evapotranspiration, crops coefficients, leaf area index and remotely-sensed vegetation indices. Agricultural Water Management,2006,79:1-27.
[126]Eissenstat D M. Costs and benefits of constructing roots of small diameter. Journal of Plant Nutrition,1992,15:763-782.
[127]Elmaloglou S T, Malamou N. Estimation of width and depth of the wetted soil volume under a surface emitter, considering root water-uptake and evaporation. Water Resource Management, 2007,21:1325-1340
[128]Faulkner H, Fayle D C F. Root development of three 5-year-old euramerican poplar clones at two plantation sites. In Proc North Am Poplar Counc Annu Meet, Brockville, Ont,1977, P8-1 to 8-10.
[129]FAO. Global Forest Products Facts and Figures.2011. Availabile at http://www.fao.org/forestry/statistics/80938/en/
[130]Feddes R A, Kowalik P J, Zaradny H. Simulation of field water use and crop yield. John Wiley & Sons, New York, NK,1978.
[131]Friend A L, Scarascia-Mugnozza G, Isebrands J G, et al. Quantification of two-year-old hybrid poplar root systems:morphology, biomass, and 14C distribution. Tree Physiology,1991,8:109-119.
[132]Fu A H, Chen Y N, Li W H. Analysis on the change of water potential of Populus euphratica Oliv. and P. russkii Jabl under different irrigation volumes in temperate desert zone. Chinese Science Bulletin,2010,55:965-972.
[133]Gardenas A I, Hopmans J W, Hanson B R, et al. Two-dimensional modelling of nitrate leaching for various fertigation scenarios under micro-irrigation. Agricultural Water Management, 2005, 74:219-242.
[134]Gerard C J, Sexton P, Shaw G. Physical factors influencing soil strength and root growth. Agronomy Journal, 1982, 74: 875-879.
[135]Gochis D J, Cuenca R H. Plant water use and crop curves for hybrid poplars. Journal of Irrigation and Drainage Engineering, 2000, 126(4): 206-214.
[136]Gong D Z, Kang S Z, Zhang L, Du T S, Yao LM. A two-dimensional model of root water uptake for single apple trees and its verification with sap flow and soil water content measurements. Agricultural Water Management, 2006, 83: 119-129.
[137]Gong D Z, Kang S Z, Yao L M, Zhang L. Estimation of evapotranspiration and its components from an apple orchard in northwest China using sap flow and water balance methods. Hydrological Processes, 2007, 21: 931-938.
[138]Granier A. Evaluation of transpiration in a Douglas-fir stand by means of sap flow measurements. Tree Physiology, 1987, 3, 309—320.
[139]Green S R, Clothier B E. Root water uptake by kiwifruit vines following partial wetting of the root zone. Plant and Soil, 1995, 173: 317-328.
[140]Green S R, Clothier B E. The root zone dynamics of water uptake by a mature apple tree. Plant and Soil, 1999, 206: 61-77.
[141]Gregory P J, McGowan M, Biscoe P V, Hunter B. Water relations of winter wheat, 1 growth of the root system. Journal of Agricultural Science, 1978, 91: 91-103.
[142]Guo D L, Xia M X, Wei X, et al.Anatomical traits associated with absorption and mycorrhizal colonization are linked to root branch order in twenty-three Chinese temperate tree species. New Phytohgist, 2008, 1 80: 673-683.
[143]Mamlyn G J. Irrigation scheduling: advantages and pitfalls of plant-based methods. Journal of Experimental Botany, 2004, 55: 2427-2436.
[144]Hansen E A. Root length in young hybrid populus plantations: its implication for border width of research plots. Forest Science, 1981, 27(4): 808-814.
[145]Hanscn E A. Irrigation short rotation intensive culture hybrid poplars. Biomass, 1988, 16(4): 237-250.
[146]Hanson B R, May D M, Schwankl L J. Effect of irrigation frequency on subsurface drip irrigated vegetables. HortTechnology, 2003,13, 115-120.
[147]Hao X M, Chen Y N, Li W H, Guo B, Zhao R F. Hydraulic lift in Populus euphratica Oliv, from the desert riparian vegetation of the Tarim River Basin. Journal of Arid Environment, 2010, 74: 905-911.
[148]Heilman P V:, Ekuan G, Fogle D. Above- and below-ground biomass and line roots of 4-year-old hybrids of Populus trichocarpa × Populus deltoicles and parental species in short-rotation culture. Canadian Journal of Forest Research, 1994, 24:11 86-1192.
[149| Herbst M, Robert J M, Rosier P T M, et al. Edge effects and forest water use: a Held study in a mixed deciduous woodland. Forest Ecology and Management, 2007, 250(3): 1 76-186.
[ 150]Hibbs D, Withrow-Robinson B, Brown D, et al. Hybrid poplar in the Willamette valley. Western Journal of Applied Forestry, 2003, 18(4): 281-285.
[151]Hillel D. Introduction to Environmental Soil Physics. Elsevier Academic Press, San Diego. 2004.
[152]Hodnett M G, Roll J P, Ah Koon P D, et al. The control of drip irrigation of sugarcane using 'index' tensiometers: some comparisons with control by the water budget method. Agricultural Water Management,1990, 17: 189-207.
[153]Hou L G, Xiao H L, Si J H, et al. Evapotranspiration and crop coefficient of Populus euphralica Oliv forest during the growing season in the extreme arid region northwest China. Agricultural Water Management,2010,97:351-356.
[154]Hughes K A, Gandar P W. Length densities, occupancies and weights of apple root systems. Plant and Soil,1993,148:211-221.
[155]Hultine K R, Nagler P L, Morino K., et al. Sap flux-scaled transpiration by tamarisk (Tamarix spp.) before, during and afer episodic defoliation by the saltcedar leaf beetle (Diorhabda carinulatd). Agricultural and Forest Meteorology,2010,150(11):1476-1475.
[156]Jackson M B, Ricard B. Physiology, biochemistry and molecular biology of plant root systems subjected to flooding of the soil, in:de Kroon, H., Visser, E.J.W. (Eds.), Root ecology. Springer, Berlin,2003:193-213.
[157]Jackson R B, Canadell J, Ehleringer J R, et al. A global analysis of root distributions for terrestrial biomes. Oecologia,1996,108:389-411.
[158]Jiang S, Pang L P, Buchan G D, et al. Modeling water flow and bacterial transport in undisturbed lysimeters under irrigations of dairy shed effluent and water using HYDRUS-1D. Water Resource,2010,44:1050-1061.
[159]Kellman M. Soil enrichment of neotropical savannah trees. The Journal of Ecology,1979,67: 565-577.
[160]Khamzina A, Lamers J P A, Vlek P L G. Tree establishment under deficit irrigation on degraded agricultural land in the lower Amu Darya River region, Aral Sea Basin. Forest Ecology and Management,2008,255:168-178.
[161]Kim H S, Oren R, Hinckley T M. Actual and potential transpiration and carbon assimilation in an irrigated poplar planatation. Tree Physiology,2008,28:559-577.
[162]Landsberg J J, Waring R H. A generalised model of forest productivity using simplified concepts of radiation-use efficiency, carbon balance and partitioning. Forest Ecology and management, 1997,95:209-228.
[163]Leskovar D I, Agehara S, Yoo K, et al. Crop coefficient-based deficit irrigation and planting density for onion:growth, yield, and bulb quality. HortScience,2012,47(1):31-37.
[164]Li J S, Zhang J J, Rao M Wetting patterns and nitrogen distributions as affected by fertigation strategies from a surface point source. Agricultural Water Management,2004,67:89-104.
[165]Li J S, Zhang J J, Rao M. Modeling of waterflow and nitrate transport under surface drip fertigation. Transactions of the American Society of Agricultural Engineers,2005,48:627-637.
[166]Liu Z, Dickmann D I. Responses of two hybrid Populus clones to flooding, drought and nitrogen availability. Ⅱ. Gas exchange and water relations. Canadian Journal of Botany,1992,71:927-938.
[167]Lu P, Muller W J, Chacko E K. Spatial variations in xylem sap flux density in the trunk of orchard-grown, mature mango trees under changing soil water conditions. Tree Physiology,2000, 20:683-692.
[168]Lu P, Woo K C, Liu Z T. Estimation of whole-plant transpiration of bananas using sap flow measurements. Journal of Experimental Botany,2002,53(375):1771-1779.
[169]Lu P, Urban L, Zhao P. Granier's thermal dissipation probe (TDP) method for measuring sap flow in trees:theory and practice. Acta Botanica Sinica,2004,46(6):631-646.
[170]Ma L H, Wu P T, Wang Y K. Spatial distribution of roots in a dense jujube plantation in the semiarid hilly region of the Chinese Loess Plateau. Plant and Soil,2012,354:57-68.
[171]Mapfumo E, Aspinall D, Hancock T W. Growth and development of roots of grapevine(Vitis vinifera L.) in relation to water uptake from soil. Annals of Botany, 1994, 74: 75-85.
[172]Matthews C J, Braddock R D, Sander G C. Modeling How through a one-dimensional multi layered soil profile using the method of lines. Environmental Model Assess, 2004, 9: 103-113.
[173]Mclvor I R, Douglas G B, Hurst S E, et al.Structural root growth of young Veronese poplars on erodible slopes in the southern North Island, New Zealand. Agroforest System, 2008, 72: 75-86.
[174]Mclvor I R, Douglas G B, Benavides R. Coarse root growth of Veronese poplar trees varies with position on an erodible slope in New Zealand. Agroforest System, 2009, 76: 251-264.
[175]McKenzie N J, Jacquier D W. Improving the field estimation of saturated hydraulic conductivity in soil survey. Australian Journal of Soil Research, 1997, 35: 803-825.
[176]Mercier V, Bussi C, Lescourret F, Genard M. Effects of different irrigation regimes applied during the final state of rapid growth on an early maturing peach cultivar. Irrigation Science, 2009, 27(4): 297-306.
[177]Molz F J. Models of water transport in the soil-plant system: A review.Water Resource Research, 1981,17:1245-1260.
[178]Moreno G, Obrador J J, Cubera E, et al. Fine root distribution in Dehesas of Central-Western Spain. Plant and Soil, 2005, 277: 153-162.
[179]Moriana A, Giron I F, Martin-Palomo M J, et al. New approach for olive trees irrigation scheduling using trunk diameter sensors. 2010,97: 1822-1828.
[180]Motschenbacher J M, Brye K R, Anders M M. Long-term rice-based cropping system effects on near-surface soil compaction. Agricultural Sciences, 2011, 2: 117-124.
[181]Mulia R, Dupraz C. Unusual fine root distributions of two deciduous tree species in southern France: what consequences for modelling of tree root dynamics? Plant and Soil, 2006, 281: 71-85.
[182]Musselman R C. Response of Transplanted Aspen to Drip Irrigation on Reclaimed Mine Lands. Fort Collins: USDA Forest Service Rocky Mountain Research Station, 2007.
[183]Nadezhdina N, Cermak J, Ceulemans R. Radial patterns of sap flow in woody stems; of dominant and understory species: scaling errors associated with positioning of sensors. Tree Physiology, 2002,22:907-918.
[184]Nagler P, Jetton A, Fleming J, et al. Evapotranspiraton in a cottonwood (Populus fremontii) restoration plantation estimated by sap flow and remote sensing methods. Agricultural and Forest Meteorology, 2007, 144: 95-110.
[185]O'Neill M K, Shock C C, Lombard K A, et al. Hybrid poplar (Populus ssp.) selections for arid and semi-arid intermountain regions of the western United states. Agroforestry System, 2010, 79: 409-418.
[186]Patel N, Rajput T B S. Dynamics and modeling of soil water under subsurface drip irrigated onion. Agriculture Water Management, 2008, 95: 1-15.
[187]Pearson C H, Halvorson A D, Moench R D, et al. Production of hybrid poplar under short-term, intensive culture in Western Colorado. Industrial Crops and Products, 2010, 31: 492-498.
[188]Pinno B D, Wilson S D, Steinaker D F, et al. Fine root dynamics of trembling aspen in boreal forest and aspen parkland in central Canada. Annals of Forest Science,2010, 67: 710.
[189]Pregitzer K S, Dickmann D I, Flendrick R, et al. Whole-tree carbon and nitrogen partitioning in young hybrid poplars. Tree Physiology, 1990, 7: 79-93.
[190]Pregitzer K S, Friend A L. The structure and function of Populus root system. In: Stettler R F, Bradshaw H D J, Hinckley T M (Eds.), Biology of Populus and Its Implications for Management and Conservation. NRC Research Press, Ottawa,1996, pp.33 1-354.
[191]Pregitzer K S, Deforest J L, Burton A J, et al. Fine root architecture of nine north American trees. Ecological Monographs,2002,72(2):293-309.
[192]Puri S, Singh V, Bhushan B, et al. Biomass production and distribution of roots in three stands of Populus deltoides. Forest Ecology and Management,1994,65:135-147.
[193]Qin R J, Stamp P, Richner W. Impact of tillage and banded starter fertilizer on maize root growth in the top 25 centimetres of the soil. Agronomy Journal,2005,97:674-683.
[194]Or D. Drip irrigation in heterogeneous soils:steady state field experiments for stochastic model for evaluation. Soil Science Society of America Journal,1996,60:1339-1349.
[195]Oron G. Simulation of water flow in the soil under sub-surface trickle irrigation with water uptake by roots. Agricultural Water Management,1981,3:179-193.
[196]O'Shaughnessy S A, Evett S R. Canopy temperature based system effectively schedules and controls center pivot irrigation of cotton. Agricultural Water Management,2010,97(9):1310-1316.
[197]Pistocchi C, Guidi W, Piccioni E, et al. Water requirements of poplar and willow vegetation filters grown in lysimeter under Mediterranean conditions:results of the second rotation. Desalination,2009,246:137-146.
[198]Raine S R, Meyer W S, Rassam D W, et al. Soil-water and solute movement under precision irrigation:knowledge gaps for managing sustainable root zones. Irrigation Science,2007,26:91-100.
[199]Rieu M, Sposito G. Fractal fragmentation soil porosity and soil water properties:Ⅰ. Theory. Soil Science Society ofAmelica Journal,1991,55:1231-1238.
[200]Robert T, Lazarovitch N, Warrick A W, et al. Modeling salt accumulation with subsurface drip irrigation using HYDRUS-2D. Soil Science Society of America Journal,2009,73:233-240.
[201]Rood S B, Braatne J H, Hughes F M R. Ecophysiology of riparian cottonwoods:stream flow dependency, water relations and restoration. Tree Physiology,2003,23:1113-1124.
[202]Roumet C, Urcelay C, Diaz S. Suites of root traits differ between annual and perennial species growing in the field. New Phytologist,2006,170:357-368.
[203]Samuelson L J, Stokes T A, Coleman M D. Influence of irrigation and fertilization on transpiration and hydraulic properties of Populus deltoides. Tree Physiology,2007,27:765-774.
[204]Schwartzman M, Zur B. Emitter spacing and geometry of wetted soil volume. Irrigation and Drainage Engineering,1986,112(3):242-253.
[205]Sekiya N, Araki H, Yano K. Applying hydraulic lift in an agroecosystem:forage plants with shoots removed supply water to neighboring vegetable crops. Plant and Soil,2011,341:39-50.
[206]Shi C X, Zhang D D, You L Y. Sediment budget of the Yellow River delta, China:the importance of dry bulk density and implications to understanding of sedment dispersal. Marine Geology,2003,199:13-25.
[207]Shock C C, Feibert E B G, Seddigh M, et al. Water requirements and growth of irrigated hybrid poplar in a semi-arid environment in eastern Oregon. Western Journal of Applied Forestry,2002, 17(1):46-53.
[208]Shock C C, Wang F X. Soil water tension, a powerful measurement for productivity and stewardship. HortScience,2011,46:178-185.
[209]Shrive S C, McBride R A, Gordon A M. Photosynthetic and growth responses of two broad-leaf tree species to irrigation with municipal landfill leachate. Journal of Environmental Quality, 1994,23:534-542.
[210]Silva J S, Rego F C. Root distribution of a Mediterranean shrubland in Portugal. Plant and Soil, 2003,255:529-540.
[211]Simunek J, Sejna M, van Genuchten MT. The HYDRUS Software Package for Simulating Two-and Three-dimensional Movement of Water, Meat, and Multiple Solutes in Variabley-saturated Media. California: International Ground Water Modelling Center, 2006.
[212]Simunek J, van Genuchten M T, Sejna M. Development and applications of the HYDRUS and STANMOD software packages and related codes. Vado.se Zone Journal, 2008, 7: 587-600.
[213]Singh D K, Rajput T B S, Singh D K, et al. Simulation of soil wetting pattern with subsurface drip irrigation from line source. Agriculture Water Management, 2006, 83: 130-134.
[214]Singh D V, Rathore T R. Soil strength and its relation with exchangeable cations, organic carbon and finer soil fractions. Indian Journal of Agricultural Research, 2003, 37: 17-22.
[215]Siyal A A, Skaggs T H. Measured and simulated soil wetting patterns under porous clay pipe sub-surface irrigation. Agricultural Water Management, 2009, 96: 893-904.
[216]Skaggs T H, Trout T J, Simunek J, et al. Comparison of HYDRUS-2D simulations of drip irrigation with experimental observations. Journal of Irrigation and Drainage Engineering, 2004, 130:304-310.
[217]Snyder K A, Williams D G. Root allocation and water uptake patterns in riparian tree saplings: response to irrigation and defoliation. Forest Ecology and Management, 2007, 246: 222-231.
[218]Sokalska D I, Haman D Z, Szewczuk A, Sobota J, Deren D. Spatial root distribution of mature apple trees under drip irrigation system. Agricultural Water Management, 2009, 96: 917-924.
[219]Steppe K, de Pauw D J W, Doody T M, et al. A comparison of sap flux density thermal dissipation, heat pulse velocity and heat Held deformation methods. Agricultural and Forest Meteorology, 2010, 150(7/8): 1046-1056.
[220]Tufekcioglu A, Raich J W, Isenhart T M, et al. Fine root dynamics, coarse root biomass, root distribution and soil repiration in a multispecies riparian buffer in Central Iowa, USA. Agroforestry System, 1999,44: 163-174.
[221]Ugawa S, Miura S, Iwamoto K, et al. Vertical patterns of fine root biomass, morphology and nitrogen concentration in a subalpine fir-wave forest. Plant and Soil, 2010, 335: 469-478.
[222]Van Genuchten M T. A closed-form equation for predicting the hydraulic conductivity of unsaturated soils. Soil Science Society of America Journal, 1980, 44: 892-898.
[223]Vijayakumar K R, Dey S K, Chandrasekhar T R, et al. Irrigation requirement of rubber trees (Hevea brasiliensis) in the subhumid tropics. Agricultural Water Management, 1998, 35 (3): 245-259.
[224]Voltas J, Serrano L, Hernandez M, et al. Carbon isotope discrimination, gas exchange and stem growth of four Euramerican hybrid poplars under different watering regimes. New Forest, 2006, 31:435-451.
[225]Vorosmarty C J, Green P, Salisbury J, et al. Global water resources: vulnerability from climate change and population growth. Science, 2000, 289: 284-288.
[226]Vrugt J A, Hopmans J W, Simunek J. Calibration of a two-dimensional root water uptake model. Soil Science Society of America Journal, 2001, 65, 1027-1037.
[227]Wahl S, Ryser P. Root tissue structure is linked to ecological strategies of grasses. New Phytologist, 2000, 148, 459-471.
[228]Warrick A W, Amoozegard-Fard A, Lomen D O. Linearized moisture flow from line sources with water extraction. Transactions of the ASAE, 1979, 22(3): 549-553.
[229]Watt M S, Whitehead D, Richardson B, et al. Modelling the influence of weed competition on the growth of young f'inus radiate at a dryland site. Forest Ecology and management, 2003, 178: 271-286.
[230]Watt M S, Kimberley M O, Coker G, et al. Modelling the influence of weed competition on growth of young Pinus radiate. Development and parameterization of a hybrid model across an environmental gradient. Canidian Journal of Forestry Research,2007,37:607-616.
[231]Wei Y K, Jia L M, Wang L, et al. Characteristics of root growth in a fast-growing and high-yield poplar plantation under subsurface drip-irrigation. Frontiers of Forestry in China,3(1):98-105.
[232]West J, Espeleta J, Donovan L. Fine root production and turnover across a complex edaphic gradient of a Pinus palustris-Aristida stricta savanna ecosystem. Forest Ecology and Management,2004,189:397-406.
[233]Williams D G, Ehleringer J R. Intra- and interspecific variation for summer precipitation use in pinyon-juniper woodlands. Ecological Monographs,2000,70:517-537.
[234]Williams L E, Ayars J E. Grapevine water use and the crop coefficient are linear functions of the shaded area measured beneath the canopy. Agricultural and Forest Meteorology,2006,132: 201-211.
[235]Wilske B, Lu N, Wei L, et al. Poplar plantation has the potential to alter the water balance in semiarid Inner Mongolia. Journal of Environmental Management,2009,90:2762-2770.
[236]Wu P F, Ma X Q, Tigabu M, et al. Root morphological plasticity and biomass production of two Chinese fir clones with high phosphorus efficiency under low phosphorus stress. Canadian Journal of Forest Research,2011,41,228-234.
[237]Xie T, Liu X H, Sun T. The effects of groundwater table and flood irrigation strategies on soil water and salt dynamics and reed water use in the Yellow River Delta, China. Ecological Modelling,2011,222(2):241-252.
[238]Yanai R D, Park B B, Hamburg S P. The vertical and horizontal distribution of roots in northern hardwood stands of varying age. Canadian Journal of Forest Research,2006,36:450-459.
[239]Zalesny J A, Zalesny Jr. R S, Coyle D R, et al. Clonal variation in morphology of Populus root systems following irrigation with landfill leachate or water during 2 years of establishment. BioEnergy Research,2009,2(3):134-143.
[240]Zalesny Jr R S, Wiese A H, Bauer E O, et al. Sapflow of hybrid poplar(Populus nigra L.xP.maximowiczii A. Henry'NM6') during phytoremediation of landfill leachate. Biomass and Bioenergy,2006,30:784-793.
[241]Zang U, Lamersdorf N, Borken W. Response of the fine root system in a Norway spruce stand to 13 years of reduced atmospheric nitrogen and acidity input. Plant and Soil,2010,339:435-445.
[242]Zhang H P, Morison J I L, Simmonds L P. Transpiration and water relations of poplar trees growing close to the water table. Tree Physiology,1999,19:563-573.
[243]Zhou Q Y, Kang S Z, Li F S, et al. Comparison of dynamic and static APRI-models to simulate soil water dynamics in a vineyard over the growing season under alternate partial root-zone drip irrigation. Agricultural Water Management,2008,95(7):767-775.
[244]Zhou Z C, Shangguang Z P. Vertical distribution of fine roots in relation to soil factors in Pinus tabulaeformis Carr. Forest of the Loess Plateau of China. Plant and Soil,2007,291:119-129.
[245]Zhu Y H, Ren L L, Skaggs T H, et al. Simulation of Populus euphratica root uptake of groundwater in an arid woodland of the Ejina Basin, China. Hydrological Processes,2009,23: 2460-2469.
[246]Zomer R J, Bossio D A, Trabucco A, et al. Trees and Water:Smallholder Agroforestry on Irrigated Lands in Northern India. IWMI Research Report 122, International Water Management Institute, Colombo,Sri Lanka,2007.
[2]陈亚新,康绍忠.非充分灌溉原理.北京：水利电力出版社,1995.
[3]程先军,许迪.地下滴灌土壤水运动和溶质运移的数学模型及验证.农业工程学报,2001,17(6)：1-4.
[4]成向荣,黄明斌,邵明安.沙地小叶杨和柠条细根分布与土壤水分消耗的关系.中国水土保持科学,2008,6(5)：77-83.
[5]党宏忠,周泽福,张劲松,等.柠条主根液流测定中ΔTmax与气象因子间的关系及时间步长的确定.生态学报,2010,30(3)：0587-0593.
[6]董文怡.毛白杨苗期水肥耦合效应研究.北京：北京林业大学,2011.
[7]方晓娟,李吉跃,聂立水,等.毛白杨杂种无性系生长及耗水特性研究.西北林学院学报,2010,25(5)：12-17.
[8]冯起,司建华,李建林,等.胡杨根系分布特征与根系吸水模型建立.地球科学进展,2008,23(7)：765-772.
[9]国家林业局森林资源管理司.全国森林资源统计—第七次全国森林资源清查.北京：国家林业局,2010.
[10]贺康宁.林地土壤水分运动的数学模型.北京林业大学学报,1992,14(1)：77-86.
[11]贾黎明,韦艳葵,李延安等.地下滴灌条件下杨树速生丰产林生长与光合特性.林业科学,2004,40(2)：61-67.
[12]贾黎明,刘诗琦,祝令辉,等.我国杨树林的碳储量和碳密度.南京林业大学学报(自然科学版),2013,37(2)：1—7.
[13]康向阳,朱之悌.三倍体毛白杨在我国纸浆林生产中的地位与作用.北京林业大学学报,2002,24(增刊)：51-56.
[14]米剑斌,工全九.土壤水分特征曲线模型比较分析.水土保持学报,2003,17(1)：137-140.
[15]雷志栋,杨诗秀.非饱和土壤水一维流动的数值模拟.土壤学报,1982,19(2)：141-152.
[16]李道西,罗金耀,彭世彰.地下滴灌土壤水分运动室内试验研究.灌溉排水学报,2004,4：26-28.
[17]李恩羊.渗灌条件下土壤水分运动的数学模拟.水利学报,1982,4：1-10.
[18]李久生,杨凤艳,栗岩峰.层状土壤质地对地下滴灌水氮气分布的影响.农业工程学报,2009,25(7)：25-31.
[19]刘晨峰,张志强,孙阁,等.基于涡度相关法和树干液流法评价杨树人工林生态系统蒸发散及其环境响应.植物生态学报,2009,33(4)：706-718.
[20]刘奉觉,郑世凯,臧道群.田间供水与杨树生长关系的研究.Ⅰ.供水处理对杨树生长、树体结构和叶量的影响.林业科学研究,1988a,1(2)：153-161.
[21]刘奉觉,郑世凯,臧道群.田间供水与杨树生长关系的研究.Ⅱ.田间供水、蒸腾耗水与材积产量的关系分析及林木蓄水量的估算.林业科学研究,1988b,1(3)：252-258.
[22]刘庆新,孟平.张劲松,等.基于侧柏液流的测定对Graniet原始公式系数进行校止.生态学报,2013,33(6)：1944-1951.
[23]刘新平,张铜会,何玉惠,等.科尔沁沙地三种常见乔木根—土届面水分再分布探讨.生态环境学报,2009,18(6)：2360-2365.
[24]刘玉春,李久生.毛管埋深和层状质地对番茄滴灌水氮利用效率的影响.农业工程学报,2009a,25(6)：7-12.
[25]刘玉春,李久生.毛管埋深和土壤层状质地对地下滴灌番茄根区水氮动态和根系分布的影响.水利学报,2009b,40(7)：782-790.
[26]刘玉春,李久生.滴灌灌溉计划制定中毛管埋深对负压计布置方式的影响.农业工程学报,2010,26(4)：18-24.
[27]李广德.三倍体毛白杨速生纸浆林蒸腾耗水特性及灌溉制度研究.北京：北京林业大学,2010.
[28]李光永.地埋点源非饱和土壤水运动的数值模拟.水利学报,1996,(11)：47—56.
[29]李光永.微灌原理与研究紧张.//康绍忠.农业水土工程概论,2007：452-482.
[30]李久生,张建君,饶敏杰.滴灌施肥灌溉的水氮运移数学模拟及试验验证.水利学报,2005,36(8)：1-10.
[31]李贤伟,张健,陈文德,等.三倍体毛白杨—黑麦草复合模式细根和草根分布与生长特征.草业学报,2005,14(6)：73-78.
[32]罗毅,徐建新,李宝萍.地表下滴灌土壤水分运动数值模拟.华北水利水电学院学报,1995,16(2)：1-9.
[33]罗毅,于强,欧阳竹,唐登银,等.利用精确的田间实验资料对几个常用根系吸水模型的评价与改进.水利学报,2000,4：73-80.
[34]绿色新闻网.三倍体毛白杨推广课题通过验收2009.http://news.bjfu.edu.cn/jxky/25607.htm
[35]马晖,于卫平,黄利江,等.杨树速生丰产林的节水灌溉试验.林业科学研究,2004,17(增刊)：119-121.
[36]马履一.国内外土壤水分研究现状和进展.世界林业研究,1997,5：26-32.
[37]马履一.山坡林地开放渗透系中土壤水分物理—生态的立地研究.北京：北京林业大学,1995.
[38]马孝义,谢建波,康银红.重力式地下滴灌土壤水分运动规律的模拟研究.灌溉排水学报,2006,25(6)：5-10.
[39]马孝义.作物水分信息采集与精量控制用水技术.//康绍忠.农业水土工程概论,2007：358-389.
[40]马秀玲,陆光明,徐祝龄,等.农林复合系统中林带和作物的根系分布特征.中国农业大学学报,1997,2(1)：109-116.
[41]马玉敏,王迎,玄成龙,等.三倍体毛白杨无性系生长形状研究.山东林业科技,2005,5：11-14.
[42]孟平,张劲松,王鹤松,等.苹果树蒸腾规律及其与冠层微气象要素的关系.生态学报,2005,25(5)：1075-1081.
[43]潘成忠,上官周平.黄土区次降雨条件下林地径流和侵蚀产沙形成机制：以人工油松林和次生山杨林为例.应用生态学报,2005,16(9)：1579-1602.
[44]任忠秀,聂立水,张强,等.水氮耦合下毛白杨无性系材积生长规律及品种选择.中南林业科技大学学报,2011,31(8)：187-193.
[45]桑玉强,刘玉军,吴文良,等.毛乌素沙地新疆杨生长季节蒸腾耗水规律.东北林业大学学报,2008,36(9)：28-31,
[46]沈国舫.对发展我国速生丰产林有关问题的思考.世界林业研究1992,4：67-74.
[47]史册,范文波,朱红凯,等.不同灌水梯度下新疆杨耗水过程与灌溉制度初步研究.中国农村水利水电,2011,9：1—7.
[48]师伟,王政权,刘金梁,等.帽儿山天然次生林20个阔叶树种细根形态.植物生态学报,2008,32(6)：1217-1226.
[49]时新宁,张振文,黄支全.沙地防护林滴灌技术研究.林业科学研究,2004,17(增刊)：15-22.
[50]苏文锷,张冠宗.新疆十旱地区杨树的灌溉造林.八一农学院学报,1989,39：42-45.
[51]宋曰钦.三倍体毛白杨纸浆林地力维持技术理论及关键技术研究,北京：北京林业大学,2009.
[52]宋曰钦,翟明普,贾黎明,等.不同年龄三倍体毛白杨纸浆林生长期间细根变化规律.生态学杂志,2010,29(9)：1696--1702.
[53]宋子刚,周文权,王彦辉.毛白杨农田防护林带细根分布特征.林业资源管理,2009,6：96-101.
[54]孙鹏森.京北水源保护林格局及不同尺度树种耗水特性的研究.北京：北京林业大学,2000.
[55]孙守家,孟平,张劲松,等.华北石质山区核桃-绿豆复合系统氘同位素变化及其水分利用.生态学报,2010,30(14)：3717-3726
[56]孙兆地,聂立水,辛颖,等.水氮耦合效应对三倍体毛白杨林木生长状况的影响.土壤通报,2012,43(4)：896-902.
[57]田富强,胡和平.基于常微分方法求解器的Richards方程数值模型.清华大学学报(自然科学版),2007,47(6)：785-788.
[58]王葆芳,朱灵益.灌溉对群众杨生长条件的调控作用的研究.林业科学,1992,28(6)：555-560.
[59]王葆芳,杨晓晖,江泽平,等.干旱区杨树用材林土壤特性和林木生长对供水的响应.干旱区资源与环境,2006,20(6)：156-162.
[60]王力,邵明安,王全九.林地土壤水分运动研究综述.林业科学,2005,41(2)：147-153.
[61]王文全,贾渝彬,胥丽敏,等.毛白杨根系分布的研究.河北农业大学学报,1997,20(1)：24-29.
[62]王文全,贾玉彬,李惠卓等.毛白杨幼林灌溉效应及其特点分析.南京林业大学学报,2000,24(1)：17-22.
[63]王文全,李秀江,贾玉彬,等.沙地毛白杨速生丰产林节水灌溉的研究.河北农业大学学报,2001,24(1)：33-37.
[64]王展,周云成,虞娜,等.以分形理论估计棕壤水分特征曲线的可行性研究.沈阳农业大学学报,2005,36(5)：570-574.
[65]王振华,吕德生,温新明,等.地下滴灌对棉花生理性状及产量影响的研究.节水灌溉,2006,4：11—13.
[66]王政权,郭大力.根系生态学.植物生态学报,2008,32(6)：1213—1216.
[67]王治军,雒天峰.滴灌条件下侧柏林地根区土壤水分运动规律研究.干旱地区农业,2008,26(4)：13-16.
[68]卫星,刘颖,陈海波.黄波罗不同根序的解剖结构及其功能异质性.植物生态学报,2008,32(6)：1238-1247.
[69]韦艳葵,贾黎明,刑长山.滴灌在林业上应用的研究.世界林业研究,2003,16(4)：38-43.
[70]温远光,刘世荣.我国主要森林生态系统类型降雨截留规律的数量分布.林业科学,1995,31(4)：289-298.
[71]席本野,贾黎明,刘寅,等.宽窄行栽植模式下三倍体毛白杨休吸水根系的空间分布与模拟.浙 江林学院学报,2010,27(2)：259-265.
[72]席本野,贾黎明,王烨,等.地下滴灌条件下三倍体毛白杨根区土壤水分动态模拟.应用生态学报,2011,22(1)：21-28.
[73]席本野,王烨,贾黎明,司静,向地奎.宽窄行栽植模式下三倍体毛白杨根系分布特征及其与根系吸水的关系.生态学报,2011,31(1)：47-57.
[74]席本野,王烨,邸楠,等.地下滴灌下土壤水势对毛白杨纸浆林生长及生理特性的影响.生态学报,2012,32(17)：5318-5329.
[75]徐贵青,李彦.共生条件下三种荒木灌木的根系分布特征及其对降水的响应.生态学报,2009,29(1)：130--137.
[76]仵峰,彭贵方,吕谋超,等.地下滴灌条件下土壤水分运动模型.灌溉排水,1996,15(3)：24-29.
[77]向师庆,赵相华.北京主要造林树种的根系研究.北京林学院学报,1981,2：19-32.
[78]燕辉,刘广全,李红生.青杨人工林根系生物量、表面积和根长密度变化.应用生态学报,2010,21(11)：2763-2768.
[79]杨建伟,梁宗锁,韩蕊莲,等.不同干旱土壤条件下杨树的耗水规律及水分利用效率研究.植物生态学报,2004,28(5)：630--636.
[80]余伟莅,庞德胜,田永祯,等.不同灌溉处理杨树新品种生长量比较.内蒙古林业科技,2007,33(4)：1-3.
[81]张爱莉.最经济的灌水法—地下滴灌.灌溉排水,1995,14(1)：50-52.
[82]张广才,张振文,时新宁,等.滴灌在沙地防护林上应用的综合效益初步研究.林业科学研究,2004,17(增刊)：78-82.
[83]张明福.节水灌溉小管出流技术在杨树丰产林建设中的应用.林业技术,2007,6：12-13.
[84]张平冬,康向阳,赵光荣,等.三倍体毛白杨超短轮伐纸浆林生长量与密度关系研究.西北林学院学报,2009,24(4)：121-124.
[85]张思聪,惠士博,雷志栋,等.水平非饱和土壤水二维运动的准解析解.水利学报,1986,17(3)：54-60.
[86]张小由,康尔泗,司建华,等.黑河下游胡杨林耗水规律研究.干旱区资源与环境,2006,20(1)：195-197.
[87]张宇清,齐实,邹青,等.梯田埂坎杨树的根系分布研究.西北林学院学报,2002,17(2)：6-9.
[88]张振华,蔡焕杰,杨润亚等.滴灌入渗土壤水分分布的数值研究.水土保持研究,2004,11(3)：91-94.
[89]郑世锴.杨树丰产栽培.北京：金盾出版社,2006.
[90]周云城.地下滴灌土壤水分运动过程的数值解析与模拟.沈阳：沈阳农业大学,2005.
[91]朱强根,张焕朝,方升佐,等.苏北杨树人工林细根分布及其季节动态.林业科技开发,2008,22(3)：45-48.
[92]朱望先,王爱珍.杨树沟灌试验报告.新疆林业,1983,3：18-19.
[93]朱之悌,林惠斌,康向阳.毛白杨异源三倍体B301等无性系选育的研究.林业科学,1995,31(6)：499-505.
[94]Adiku S G K, Rose C W, Braddck R D, et al. On the simulation of root water extraction: examination of a minimum energy hypothesis. Soil Science,2000,165:226-236.
[95]Al Afas N, Marron N, Zavalloni C, et al. Growth and production of a short-rotation coppice culture of poplar-Ⅳ:fine root characteristics of five poplar clones.Biomass and Bioenergy, 2008, 32: 494-502.
[96]Allen S J, Hall R L, Rosier P T W. Transpiration by two poplar varieties grown as coppice for biomass production. Tree Physiology, 1999, 19:493-501.
[97]Anderson T M, Starmer W T, Thome M. Bimodal root diameter distributions in Serengeti grasses exhibit plasticity in response to defoliation and soil texture: implications for nitrogen uptake. Functional Ecology, 2007, 21: 50-60.
[98]Atkinson D. The distribution and effectiveness of the roots of tree crops. Horticultural Reviews, 1980,2:424-490.
[99]Bauerle T L, Smart D R, Bauerle W L, et al. Root foraging in response to heterogeneous soil moisture in two grapevines that differ in potential growth rate. New Phytologist, 2008, 179: 857-866.
[100]Block R M A, Van Rees K C J, Knight J D. A review of fine root dynamics in Populus plantations. Agroforestry Systems, 2006, 67: 73-84.
[101]Boast C W, Robertson TM. A 'micro-lysimeter' method for determining evaporation from bare soil: description and laboratory evaluation. Soil Science Society of America Journal, 1982, 46: 689-696.
[102]Brandt A, Bresler E, Diner N, et al. Infiltration from a trickle source: I. mathematical models. Soil Science Society of America Journal, 1971, 35(5): 675-682.
[103]Brooks R H, Corey A T. Properties of porous media affecting fluid flow. Journal of Irrigation and Drainage Division, Proceedings of the American Society of Civil Engineers, 1966, 92(IR2): 61-68.
[104]Bucks D A, Erie L J, French O F, Nakayama F S, Pew W D. Subsurface trickle irrigation management with multiple cropping. Transaction of ASAE, 1981,24: 1482-1489.
[105]Caldwell D S, Spurgeon W E, Manges H L. Frequency of irrigation for subsurface drip-irrigated corn. Transaction of the ASAE, 1994, 37(6): 1099-1103
[106]Caldwell M M, Dawson T E, Richards J H. Hydraulic lift: consequences of water efflux from the roots of plants. Oecologia, 1998, 113:151-161.
[107]Camp C R. Subsurface drip irrigation: a review. Transactions of the American Society of Agricultural Engineers, 1998, 41(5): 1353-1367.
[108]Caruso G, Rapoport H F, Gucci R. Long-term evaluation of yield components of young olive trees during the onset of fruit production under different irrigation regimes. Irrigation Science, 2013, 31(1): 37-47.
[109]Ceulemans R. Deraedt W. Production physiology and growth potential of poplars under short-rotation forestry culture. Forest Ecology and Management, 1999, 121: 9-23.
[110]Chisersson L. Biomass production of intensively grown poplar in the southernmost part of Sweden: Observations of characters, traits and growth potential. Biomass and Bioenergy, 2006, 30: 497-508.
[111]Clothier B E, Green S R. Rootzone processes and the efficient use of irrigation water. Agricultural Water Management, 1994,25: 1-12.
[112]Clothier B E, Green S R. Roots: the big movers of water and chemical in soil. Soil Science, 1997, 162:534-543.
[113]Coleman M. Spatial and temporal patterns of root distribution in developing stands of four woody crop species grown with drip irrigation and fertilization. Plant and Soil, 2007, 299: 195-213.
[114]Cook F J, Thorburn P J, Fitch P, et al. WetUp: a software tool to display approximate wetting patterns from drippers. Irrigation Science,2003,22(3):129-134.
[115]Cox G, Fischer D, Hart S C, et al. Nonresponse of native cottonwood trees to water additions during summer drought. Western North American Naturalist,2005,65(2):175-185.
[116]Coyle D R, Coleman M D. Forest production responses to irrigation and fertilization are not explained by shifts in allocation. Forest Ecology and Management,2005,208:137-152.
[117]Crockford R H, Richardson D P. Partioning of rainfall into throughfall, stemflow and interception:effect of forest type, ground cover and climate. Hydrological Processes,2000,14: 2903-2920.
[118]Daniel H. Introduction to Environmental Soil Physics. Elsevier Academic Press,2004.
[119]Dawson T E, Pate J S. Seasonal water uptake and movement in root systems of Australian phraeatophytic plants of dimorphic root morphology:a stable isotope investigation. Oecologia, 1996,107:13-20.
[120]de Medeiros G A, Arruda F B, Sakai E. Crop coefficient for irrigated beans derived using three reference evaporation methods. Agricultural and Forest Meteorology,2005,135:135-143.
[121]Dickmann D I, Nguyen P V, Pregitzer K S. Effects of irrigation and coppicing on above-ground growth, physiology, and fine-root dynamics of two field-grown hybrid poplar clones. Forest Ecology and Management,1996,80:163-174.
[122]Dlotra J, Munoz P. Simulation of nitrogen leaching from a fertigated crop rotation in a Mediterranean climate using the EU-Rotate_N and Hydrus-2D models. Agricultural Water Management,2010,97:277-285.
[123]Domenicano S, Coll L, Messier C, et al. Nitrogen forms affect root structure and water uptake in the hybrid poplar. New Forest,2011,42:347-362.
[124]Douglas G B, Mclvor I R, Potter J F, et al. Root distribution of poplar at varying densities on pastoral hill country. Plant and Soil,2010,333:147-161.
[125]Duchemin B, Hadria R, Erraki S, et al. Monitoring wheat phenology and irrigation in Cenral Morocco:on the use of realationships between evapotranspiration, crops coefficients, leaf area index and remotely-sensed vegetation indices. Agricultural Water Management,2006,79:1-27.
[126]Eissenstat D M. Costs and benefits of constructing roots of small diameter. Journal of Plant Nutrition,1992,15:763-782.
[127]Elmaloglou S T, Malamou N. Estimation of width and depth of the wetted soil volume under a surface emitter, considering root water-uptake and evaporation. Water Resource Management, 2007,21:1325-1340
[128]Faulkner H, Fayle D C F. Root development of three 5-year-old euramerican poplar clones at two plantation sites. In Proc North Am Poplar Counc Annu Meet, Brockville, Ont,1977, P8-1 to 8-10.
[129]FAO. Global Forest Products Facts and Figures.2011. Availabile at http://www.fao.org/forestry/statistics/80938/en/
[130]Feddes R A, Kowalik P J, Zaradny H. Simulation of field water use and crop yield. John Wiley & Sons, New York, NK,1978.
[131]Friend A L, Scarascia-Mugnozza G, Isebrands J G, et al. Quantification of two-year-old hybrid poplar root systems:morphology, biomass, and 14C distribution. Tree Physiology,1991,8:109-119.
[132]Fu A H, Chen Y N, Li W H. Analysis on the change of water potential of Populus euphratica Oliv. and P. russkii Jabl under different irrigation volumes in temperate desert zone. Chinese Science Bulletin,2010,55:965-972.
[133]Gardenas A I, Hopmans J W, Hanson B R, et al. Two-dimensional modelling of nitrate leaching for various fertigation scenarios under micro-irrigation. Agricultural Water Management, 2005, 74:219-242.
[134]Gerard C J, Sexton P, Shaw G. Physical factors influencing soil strength and root growth. Agronomy Journal, 1982, 74: 875-879.
[135]Gochis D J, Cuenca R H. Plant water use and crop curves for hybrid poplars. Journal of Irrigation and Drainage Engineering, 2000, 126(4): 206-214.
[136]Gong D Z, Kang S Z, Zhang L, Du T S, Yao LM. A two-dimensional model of root water uptake for single apple trees and its verification with sap flow and soil water content measurements. Agricultural Water Management, 2006, 83: 119-129.
[137]Gong D Z, Kang S Z, Yao L M, Zhang L. Estimation of evapotranspiration and its components from an apple orchard in northwest China using sap flow and water balance methods. Hydrological Processes, 2007, 21: 931-938.
[138]Granier A. Evaluation of transpiration in a Douglas-fir stand by means of sap flow measurements. Tree Physiology, 1987, 3, 309—320.
[139]Green S R, Clothier B E. Root water uptake by kiwifruit vines following partial wetting of the root zone. Plant and Soil, 1995, 173: 317-328.
[140]Green S R, Clothier B E. The root zone dynamics of water uptake by a mature apple tree. Plant and Soil, 1999, 206: 61-77.
[141]Gregory P J, McGowan M, Biscoe P V, Hunter B. Water relations of winter wheat, 1 growth of the root system. Journal of Agricultural Science, 1978, 91: 91-103.
[142]Guo D L, Xia M X, Wei X, et al.Anatomical traits associated with absorption and mycorrhizal colonization are linked to root branch order in twenty-three Chinese temperate tree species. New Phytohgist, 2008, 1 80: 673-683.
[143]Mamlyn G J. Irrigation scheduling: advantages and pitfalls of plant-based methods. Journal of Experimental Botany, 2004, 55: 2427-2436.
[144]Hansen E A. Root length in young hybrid populus plantations: its implication for border width of research plots. Forest Science, 1981, 27(4): 808-814.
[145]Hanscn E A. Irrigation short rotation intensive culture hybrid poplars. Biomass, 1988, 16(4): 237-250.
[146]Hanson B R, May D M, Schwankl L J. Effect of irrigation frequency on subsurface drip irrigated vegetables. HortTechnology, 2003,13, 115-120.
[147]Hao X M, Chen Y N, Li W H, Guo B, Zhao R F. Hydraulic lift in Populus euphratica Oliv, from the desert riparian vegetation of the Tarim River Basin. Journal of Arid Environment, 2010, 74: 905-911.
[148]Heilman P V:, Ekuan G, Fogle D. Above- and below-ground biomass and line roots of 4-year-old hybrids of Populus trichocarpa × Populus deltoicles and parental species in short-rotation culture. Canadian Journal of Forest Research, 1994, 24:11 86-1192.
[149| Herbst M, Robert J M, Rosier P T M, et al. Edge effects and forest water use: a Held study in a mixed deciduous woodland. Forest Ecology and Management, 2007, 250(3): 1 76-186.
[ 150]Hibbs D, Withrow-Robinson B, Brown D, et al. Hybrid poplar in the Willamette valley. Western Journal of Applied Forestry, 2003, 18(4): 281-285.
[151]Hillel D. Introduction to Environmental Soil Physics. Elsevier Academic Press, San Diego. 2004.
[152]Hodnett M G, Roll J P, Ah Koon P D, et al. The control of drip irrigation of sugarcane using 'index' tensiometers: some comparisons with control by the water budget method. Agricultural Water Management,1990, 17: 189-207.
[153]Hou L G, Xiao H L, Si J H, et al. Evapotranspiration and crop coefficient of Populus euphralica Oliv forest during the growing season in the extreme arid region northwest China. Agricultural Water Management,2010,97:351-356.
[154]Hughes K A, Gandar P W. Length densities, occupancies and weights of apple root systems. Plant and Soil,1993,148:211-221.
[155]Hultine K R, Nagler P L, Morino K., et al. Sap flux-scaled transpiration by tamarisk (Tamarix spp.) before, during and afer episodic defoliation by the saltcedar leaf beetle (Diorhabda carinulatd). Agricultural and Forest Meteorology,2010,150(11):1476-1475.
[156]Jackson M B, Ricard B. Physiology, biochemistry and molecular biology of plant root systems subjected to flooding of the soil, in:de Kroon, H., Visser, E.J.W. (Eds.), Root ecology. Springer, Berlin,2003:193-213.
[157]Jackson R B, Canadell J, Ehleringer J R, et al. A global analysis of root distributions for terrestrial biomes. Oecologia,1996,108:389-411.
[158]Jiang S, Pang L P, Buchan G D, et al. Modeling water flow and bacterial transport in undisturbed lysimeters under irrigations of dairy shed effluent and water using HYDRUS-1D. Water Resource,2010,44:1050-1061.
[159]Kellman M. Soil enrichment of neotropical savannah trees. The Journal of Ecology,1979,67: 565-577.
[160]Khamzina A, Lamers J P A, Vlek P L G. Tree establishment under deficit irrigation on degraded agricultural land in the lower Amu Darya River region, Aral Sea Basin. Forest Ecology and Management,2008,255:168-178.
[161]Kim H S, Oren R, Hinckley T M. Actual and potential transpiration and carbon assimilation in an irrigated poplar planatation. Tree Physiology,2008,28:559-577.
[162]Landsberg J J, Waring R H. A generalised model of forest productivity using simplified concepts of radiation-use efficiency, carbon balance and partitioning. Forest Ecology and management, 1997,95:209-228.
[163]Leskovar D I, Agehara S, Yoo K, et al. Crop coefficient-based deficit irrigation and planting density for onion:growth, yield, and bulb quality. HortScience,2012,47(1):31-37.
[164]Li J S, Zhang J J, Rao M Wetting patterns and nitrogen distributions as affected by fertigation strategies from a surface point source. Agricultural Water Management,2004,67:89-104.
[165]Li J S, Zhang J J, Rao M. Modeling of waterflow and nitrate transport under surface drip fertigation. Transactions of the American Society of Agricultural Engineers,2005,48:627-637.
[166]Liu Z, Dickmann D I. Responses of two hybrid Populus clones to flooding, drought and nitrogen availability. Ⅱ. Gas exchange and water relations. Canadian Journal of Botany,1992,71:927-938.
[167]Lu P, Muller W J, Chacko E K. Spatial variations in xylem sap flux density in the trunk of orchard-grown, mature mango trees under changing soil water conditions. Tree Physiology,2000, 20:683-692.
[168]Lu P, Woo K C, Liu Z T. Estimation of whole-plant transpiration of bananas using sap flow measurements. Journal of Experimental Botany,2002,53(375):1771-1779.
[169]Lu P, Urban L, Zhao P. Granier's thermal dissipation probe (TDP) method for measuring sap flow in trees:theory and practice. Acta Botanica Sinica,2004,46(6):631-646.
[170]Ma L H, Wu P T, Wang Y K. Spatial distribution of roots in a dense jujube plantation in the semiarid hilly region of the Chinese Loess Plateau. Plant and Soil,2012,354:57-68.
[171]Mapfumo E, Aspinall D, Hancock T W. Growth and development of roots of grapevine(Vitis vinifera L.) in relation to water uptake from soil. Annals of Botany, 1994, 74: 75-85.
[172]Matthews C J, Braddock R D, Sander G C. Modeling How through a one-dimensional multi layered soil profile using the method of lines. Environmental Model Assess, 2004, 9: 103-113.
[173]Mclvor I R, Douglas G B, Hurst S E, et al.Structural root growth of young Veronese poplars on erodible slopes in the southern North Island, New Zealand. Agroforest System, 2008, 72: 75-86.
[174]Mclvor I R, Douglas G B, Benavides R. Coarse root growth of Veronese poplar trees varies with position on an erodible slope in New Zealand. Agroforest System, 2009, 76: 251-264.
[175]McKenzie N J, Jacquier D W. Improving the field estimation of saturated hydraulic conductivity in soil survey. Australian Journal of Soil Research, 1997, 35: 803-825.
[176]Mercier V, Bussi C, Lescourret F, Genard M. Effects of different irrigation regimes applied during the final state of rapid growth on an early maturing peach cultivar. Irrigation Science, 2009, 27(4): 297-306.
[177]Molz F J. Models of water transport in the soil-plant system: A review.Water Resource Research, 1981,17:1245-1260.
[178]Moreno G, Obrador J J, Cubera E, et al. Fine root distribution in Dehesas of Central-Western Spain. Plant and Soil, 2005, 277: 153-162.
[179]Moriana A, Giron I F, Martin-Palomo M J, et al. New approach for olive trees irrigation scheduling using trunk diameter sensors. 2010,97: 1822-1828.
[180]Motschenbacher J M, Brye K R, Anders M M. Long-term rice-based cropping system effects on near-surface soil compaction. Agricultural Sciences, 2011, 2: 117-124.
[181]Mulia R, Dupraz C. Unusual fine root distributions of two deciduous tree species in southern France: what consequences for modelling of tree root dynamics? Plant and Soil, 2006, 281: 71-85.
[182]Musselman R C. Response of Transplanted Aspen to Drip Irrigation on Reclaimed Mine Lands. Fort Collins: USDA Forest Service Rocky Mountain Research Station, 2007.
[183]Nadezhdina N, Cermak J, Ceulemans R. Radial patterns of sap flow in woody stems; of dominant and understory species: scaling errors associated with positioning of sensors. Tree Physiology, 2002,22:907-918.
[184]Nagler P, Jetton A, Fleming J, et al. Evapotranspiraton in a cottonwood (Populus fremontii) restoration plantation estimated by sap flow and remote sensing methods. Agricultural and Forest Meteorology, 2007, 144: 95-110.
[185]O'Neill M K, Shock C C, Lombard K A, et al. Hybrid poplar (Populus ssp.) selections for arid and semi-arid intermountain regions of the western United states. Agroforestry System, 2010, 79: 409-418.
[186]Patel N, Rajput T B S. Dynamics and modeling of soil water under subsurface drip irrigated onion. Agriculture Water Management, 2008, 95: 1-15.
[187]Pearson C H, Halvorson A D, Moench R D, et al. Production of hybrid poplar under short-term, intensive culture in Western Colorado. Industrial Crops and Products, 2010, 31: 492-498.
[188]Pinno B D, Wilson S D, Steinaker D F, et al. Fine root dynamics of trembling aspen in boreal forest and aspen parkland in central Canada. Annals of Forest Science,2010, 67: 710.
[189]Pregitzer K S, Dickmann D I, Flendrick R, et al. Whole-tree carbon and nitrogen partitioning in young hybrid poplars. Tree Physiology, 1990, 7: 79-93.
[190]Pregitzer K S, Friend A L. The structure and function of Populus root system. In: Stettler R F, Bradshaw H D J, Hinckley T M (Eds.), Biology of Populus and Its Implications for Management and Conservation. NRC Research Press, Ottawa,1996, pp.33 1-354.
[191]Pregitzer K S, Deforest J L, Burton A J, et al. Fine root architecture of nine north American trees. Ecological Monographs,2002,72(2):293-309.
[192]Puri S, Singh V, Bhushan B, et al. Biomass production and distribution of roots in three stands of Populus deltoides. Forest Ecology and Management,1994,65:135-147.
[193]Qin R J, Stamp P, Richner W. Impact of tillage and banded starter fertilizer on maize root growth in the top 25 centimetres of the soil. Agronomy Journal,2005,97:674-683.
[194]Or D. Drip irrigation in heterogeneous soils:steady state field experiments for stochastic model for evaluation. Soil Science Society of America Journal,1996,60:1339-1349.
[195]Oron G. Simulation of water flow in the soil under sub-surface trickle irrigation with water uptake by roots. Agricultural Water Management,1981,3:179-193.
[196]O'Shaughnessy S A, Evett S R. Canopy temperature based system effectively schedules and controls center pivot irrigation of cotton. Agricultural Water Management,2010,97(9):1310-1316.
[197]Pistocchi C, Guidi W, Piccioni E, et al. Water requirements of poplar and willow vegetation filters grown in lysimeter under Mediterranean conditions:results of the second rotation. Desalination,2009,246:137-146.
[198]Raine S R, Meyer W S, Rassam D W, et al. Soil-water and solute movement under precision irrigation:knowledge gaps for managing sustainable root zones. Irrigation Science,2007,26:91-100.
[199]Rieu M, Sposito G. Fractal fragmentation soil porosity and soil water properties:Ⅰ. Theory. Soil Science Society ofAmelica Journal,1991,55:1231-1238.
[200]Robert T, Lazarovitch N, Warrick A W, et al. Modeling salt accumulation with subsurface drip irrigation using HYDRUS-2D. Soil Science Society of America Journal,2009,73:233-240.
[201]Rood S B, Braatne J H, Hughes F M R. Ecophysiology of riparian cottonwoods:stream flow dependency, water relations and restoration. Tree Physiology,2003,23:1113-1124.
[202]Roumet C, Urcelay C, Diaz S. Suites of root traits differ between annual and perennial species growing in the field. New Phytologist,2006,170:357-368.
[203]Samuelson L J, Stokes T A, Coleman M D. Influence of irrigation and fertilization on transpiration and hydraulic properties of Populus deltoides. Tree Physiology,2007,27:765-774.
[204]Schwartzman M, Zur B. Emitter spacing and geometry of wetted soil volume. Irrigation and Drainage Engineering,1986,112(3):242-253.
[205]Sekiya N, Araki H, Yano K. Applying hydraulic lift in an agroecosystem:forage plants with shoots removed supply water to neighboring vegetable crops. Plant and Soil,2011,341:39-50.
[206]Shi C X, Zhang D D, You L Y. Sediment budget of the Yellow River delta, China:the importance of dry bulk density and implications to understanding of sedment dispersal. Marine Geology,2003,199:13-25.
[207]Shock C C, Feibert E B G, Seddigh M, et al. Water requirements and growth of irrigated hybrid poplar in a semi-arid environment in eastern Oregon. Western Journal of Applied Forestry,2002, 17(1):46-53.
[208]Shock C C, Wang F X. Soil water tension, a powerful measurement for productivity and stewardship. HortScience,2011,46:178-185.
[209]Shrive S C, McBride R A, Gordon A M. Photosynthetic and growth responses of two broad-leaf tree species to irrigation with municipal landfill leachate. Journal of Environmental Quality, 1994,23:534-542.
[210]Silva J S, Rego F C. Root distribution of a Mediterranean shrubland in Portugal. Plant and Soil, 2003,255:529-540.
[211]Simunek J, Sejna M, van Genuchten MT. The HYDRUS Software Package for Simulating Two-and Three-dimensional Movement of Water, Meat, and Multiple Solutes in Variabley-saturated Media. California: International Ground Water Modelling Center, 2006.
[212]Simunek J, van Genuchten M T, Sejna M. Development and applications of the HYDRUS and STANMOD software packages and related codes. Vado.se Zone Journal, 2008, 7: 587-600.
[213]Singh D K, Rajput T B S, Singh D K, et al. Simulation of soil wetting pattern with subsurface drip irrigation from line source. Agriculture Water Management, 2006, 83: 130-134.
[214]Singh D V, Rathore T R. Soil strength and its relation with exchangeable cations, organic carbon and finer soil fractions. Indian Journal of Agricultural Research, 2003, 37: 17-22.
[215]Siyal A A, Skaggs T H. Measured and simulated soil wetting patterns under porous clay pipe sub-surface irrigation. Agricultural Water Management, 2009, 96: 893-904.
[216]Skaggs T H, Trout T J, Simunek J, et al. Comparison of HYDRUS-2D simulations of drip irrigation with experimental observations. Journal of Irrigation and Drainage Engineering, 2004, 130:304-310.
[217]Snyder K A, Williams D G. Root allocation and water uptake patterns in riparian tree saplings: response to irrigation and defoliation. Forest Ecology and Management, 2007, 246: 222-231.
[218]Sokalska D I, Haman D Z, Szewczuk A, Sobota J, Deren D. Spatial root distribution of mature apple trees under drip irrigation system. Agricultural Water Management, 2009, 96: 917-924.
[219]Steppe K, de Pauw D J W, Doody T M, et al. A comparison of sap flux density thermal dissipation, heat pulse velocity and heat Held deformation methods. Agricultural and Forest Meteorology, 2010, 150(7/8): 1046-1056.
[220]Tufekcioglu A, Raich J W, Isenhart T M, et al. Fine root dynamics, coarse root biomass, root distribution and soil repiration in a multispecies riparian buffer in Central Iowa, USA. Agroforestry System, 1999,44: 163-174.
[221]Ugawa S, Miura S, Iwamoto K, et al. Vertical patterns of fine root biomass, morphology and nitrogen concentration in a subalpine fir-wave forest. Plant and Soil, 2010, 335: 469-478.
[222]Van Genuchten M T. A closed-form equation for predicting the hydraulic conductivity of unsaturated soils. Soil Science Society of America Journal, 1980, 44: 892-898.
[223]Vijayakumar K R, Dey S K, Chandrasekhar T R, et al. Irrigation requirement of rubber trees (Hevea brasiliensis) in the subhumid tropics. Agricultural Water Management, 1998, 35 (3): 245-259.
[224]Voltas J, Serrano L, Hernandez M, et al. Carbon isotope discrimination, gas exchange and stem growth of four Euramerican hybrid poplars under different watering regimes. New Forest, 2006, 31:435-451.
[225]Vorosmarty C J, Green P, Salisbury J, et al. Global water resources: vulnerability from climate change and population growth. Science, 2000, 289: 284-288.
[226]Vrugt J A, Hopmans J W, Simunek J. Calibration of a two-dimensional root water uptake model. Soil Science Society of America Journal, 2001, 65, 1027-1037.
[227]Wahl S, Ryser P. Root tissue structure is linked to ecological strategies of grasses. New Phytologist, 2000, 148, 459-471.
[228]Warrick A W, Amoozegard-Fard A, Lomen D O. Linearized moisture flow from line sources with water extraction. Transactions of the ASAE, 1979, 22(3): 549-553.
[229]Watt M S, Whitehead D, Richardson B, et al. Modelling the influence of weed competition on the growth of young f'inus radiate at a dryland site. Forest Ecology and management, 2003, 178: 271-286.
[230]Watt M S, Kimberley M O, Coker G, et al. Modelling the influence of weed competition on growth of young Pinus radiate. Development and parameterization of a hybrid model across an environmental gradient. Canidian Journal of Forestry Research,2007,37:607-616.
[231]Wei Y K, Jia L M, Wang L, et al. Characteristics of root growth in a fast-growing and high-yield poplar plantation under subsurface drip-irrigation. Frontiers of Forestry in China,3(1):98-105.
[232]West J, Espeleta J, Donovan L. Fine root production and turnover across a complex edaphic gradient of a Pinus palustris-Aristida stricta savanna ecosystem. Forest Ecology and Management,2004,189:397-406.
[233]Williams D G, Ehleringer J R. Intra- and interspecific variation for summer precipitation use in pinyon-juniper woodlands. Ecological Monographs,2000,70:517-537.
[234]Williams L E, Ayars J E. Grapevine water use and the crop coefficient are linear functions of the shaded area measured beneath the canopy. Agricultural and Forest Meteorology,2006,132: 201-211.
[235]Wilske B, Lu N, Wei L, et al. Poplar plantation has the potential to alter the water balance in semiarid Inner Mongolia. Journal of Environmental Management,2009,90:2762-2770.
[236]Wu P F, Ma X Q, Tigabu M, et al. Root morphological plasticity and biomass production of two Chinese fir clones with high phosphorus efficiency under low phosphorus stress. Canadian Journal of Forest Research,2011,41,228-234.
[237]Xie T, Liu X H, Sun T. The effects of groundwater table and flood irrigation strategies on soil water and salt dynamics and reed water use in the Yellow River Delta, China. Ecological Modelling,2011,222(2):241-252.
[238]Yanai R D, Park B B, Hamburg S P. The vertical and horizontal distribution of roots in northern hardwood stands of varying age. Canadian Journal of Forest Research,2006,36:450-459.
[239]Zalesny J A, Zalesny Jr. R S, Coyle D R, et al. Clonal variation in morphology of Populus root systems following irrigation with landfill leachate or water during 2 years of establishment. BioEnergy Research,2009,2(3):134-143.
[240]Zalesny Jr R S, Wiese A H, Bauer E O, et al. Sapflow of hybrid poplar(Populus nigra L.xP.maximowiczii A. Henry'NM6') during phytoremediation of landfill leachate. Biomass and Bioenergy,2006,30:784-793.
[241]Zang U, Lamersdorf N, Borken W. Response of the fine root system in a Norway spruce stand to 13 years of reduced atmospheric nitrogen and acidity input. Plant and Soil,2010,339:435-445.
[242]Zhang H P, Morison J I L, Simmonds L P. Transpiration and water relations of poplar trees growing close to the water table. Tree Physiology,1999,19:563-573.
[243]Zhou Q Y, Kang S Z, Li F S, et al. Comparison of dynamic and static APRI-models to simulate soil water dynamics in a vineyard over the growing season under alternate partial root-zone drip irrigation. Agricultural Water Management,2008,95(7):767-775.
[244]Zhou Z C, Shangguang Z P. Vertical distribution of fine roots in relation to soil factors in Pinus tabulaeformis Carr. Forest of the Loess Plateau of China. Plant and Soil,2007,291:119-129.
[245]Zhu Y H, Ren L L, Skaggs T H, et al. Simulation of Populus euphratica root uptake of groundwater in an arid woodland of the Ejina Basin, China. Hydrological Processes,2009,23: 2460-2469.
[246]Zomer R J, Bossio D A, Trabucco A, et al. Trees and Water:Smallholder Agroforestry on Irrigated Lands in Northern India. IWMI Research Report 122, International Water Management Institute, Colombo,Sri Lanka,2007.
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