尕海湿地不同密度下甘肃马先蒿根系分叉数与连接数、分支角度的关系
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摘要
根系构型决定根系分布及其对养分和水分的吸收效率,是植物根系与胁迫生境相互适应的结果。采用标准化主轴估计(Standardized major axis estimation, SMA)法,并采用全根挖掘和Win-RHIZO根系分析仪相结合的方法,按照甘肃马先蒿种群密度设置I(10—31株/m~2)、Ⅱ(32—53株/m~2)、Ⅲ(54—75株/m~2)3个样地,研究了尕海湿地不同密度下甘肃马先蒿(Pedicularis kansuensis)根系分叉数与连接数及分支角度的关系。结果表明:随着种群密度由高到低转变,甘肃马先蒿的高度、盖度、地上生物量、根系分叉数及外部连接数逐渐减小,地下生物量、根系内部连接数、分支角度逐渐增大;甘肃马先蒿根系分叉数与内部连接数、外部连接数及分支角度均呈异速生长关系,随着种群密度由高到低转变,甘肃马先蒿根系内部连接数与分支角度增加的速度逐渐大于分叉数与外部连接数减小的速度,根系分叉数与内部连接数的异速斜率逐渐减小,与外部连接数、分支角度的异速斜率逐渐增大。甘肃马先蒿在高密度倾向于密集型根系构型构建模式,在低密度选择扩散型根系生长模式,体现了高寒湿地植物种群应对资源多重竞争的生态适应机制。
The root architecture determines the root distribution and the search efficiency of water and nutrients, which is the result of the adaptability of plant roots and stress habitats. The object of this study was to examine the relationship between root forks and link number, branch angle of Pedicularis kansuensis in response to density conditions. The study site was located in Gahai Wetland, Gansu Province, China(102.08°—102.47° E, 33.97°—34.32° N). The altitude of the study site is 3430—3435 m, whereas the average annual temperature is 2.3℃. Sixty samples(1 m×1 m) were set up along the river bank to investigate the density of P. kansuensis in August 2016. Population density was categorized as low(I, 10—31 plant/m~2), medium(II, 32—53 plant/m~2), and high(III, 54—75 plant/m~2). The density, height, coverage, and above-ground biomass of the plant communities were recorded from 1 m × 1 m plots in the three densities with six replications. Thirty plants of P. kansensis were selected; the above-ground parts of those plants were cut while roots were collected by excavating the whole root system, and both were taken back to lab. Afterwards, the soil cores(30 cm × 30 cm × 50 cm) were dug from six grids(30 cm × 30 cm) in three densities. The sieve(mesh size = 0.25 mm) was used to clean the soil core in the nearby river, and the roots were taken to the lab. Afterwards, we adopted a method to stratify sampling(0—50 cm). In the laboratory, the roots were scanned with Win-RHIZO to measure the root forks and link number. The biomasses of different plots were put in an oven(at 105℃ for 30 min) for green removal, and drying(at 80℃ for 12 h), and then measured. Similarly, the soil moisture content was also measured by oven-drying(at 105℃ for 24 h). The results showed that as the population density changed from high-medium to low-medium, the coverage, height and above-ground biomass, root forks and external link number of the P. kansuensis decreased, whereas the below-ground biomass, root internal link number, and branch angle of P. kansuensis increased. The was an allometric relation between the root forks and link number, and branch angle of P. kansuensis. Additionally, the growth speed of the root internal link number and branch angle was greater than the decrease speed of root forks and external link number. The allometric slope of the root forks and external link number decreased, but that of the root forks and internal link number and branch angle increased. With a change in density, the root forks and external link number of P. kansuensis decreased, and the root internal link number and branch angle increased. These results revise the ecological adaptation mechanism of plant populations to multiple resource competitions in alpine wetlands under the restriction of density.
The root architecture determines the root distribution and the search efficiency of water and nutrients, which is the result of the adaptability of plant roots and stress habitats. The object of this study was to examine the relationship between root forks and link number, branch angle of Pedicularis kansuensis in response to density conditions. The study site was located in Gahai Wetland, Gansu Province, China(102.08°—102.47° E, 33.97°—34.32° N). The altitude of the study site is 3430—3435 m, whereas the average annual temperature is 2.3℃. Sixty samples(1 m×1 m) were set up along the river bank to investigate the density of P. kansuensis in August 2016. Population density was categorized as low(I, 10—31 plant/m~2), medium(II, 32—53 plant/m~2), and high(III, 54—75 plant/m~2). The density, height, coverage, and above-ground biomass of the plant communities were recorded from 1 m × 1 m plots in the three densities with six replications. Thirty plants of P. kansensis were selected; the above-ground parts of those plants were cut while roots were collected by excavating the whole root system, and both were taken back to lab. Afterwards, the soil cores(30 cm × 30 cm × 50 cm) were dug from six grids(30 cm × 30 cm) in three densities. The sieve(mesh size = 0.25 mm) was used to clean the soil core in the nearby river, and the roots were taken to the lab. Afterwards, we adopted a method to stratify sampling(0—50 cm). In the laboratory, the roots were scanned with Win-RHIZO to measure the root forks and link number. The biomasses of different plots were put in an oven(at 105℃ for 30 min) for green removal, and drying(at 80℃ for 12 h), and then measured. Similarly, the soil moisture content was also measured by oven-drying(at 105℃ for 24 h). The results showed that as the population density changed from high-medium to low-medium, the coverage, height and above-ground biomass, root forks and external link number of the P. kansuensis decreased, whereas the below-ground biomass, root internal link number, and branch angle of P. kansuensis increased. The was an allometric relation between the root forks and link number, and branch angle of P. kansuensis. Additionally, the growth speed of the root internal link number and branch angle was greater than the decrease speed of root forks and external link number. The allometric slope of the root forks and external link number decreased, but that of the root forks and internal link number and branch angle increased. With a change in density, the root forks and external link number of P. kansuensis decreased, and the root internal link number and branch angle increased. These results revise the ecological adaptation mechanism of plant populations to multiple resource competitions in alpine wetlands under the restriction of density.
引文
[1] 黄晶晶,井家林,曹德昌,张楠,李景文,夏延国,吕爽.不同林龄胡杨克隆繁殖根系分布特征及其构型.生态学报,2013,33(14):4331- 4342.
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[7] 夏菲.黄土高原子午岭辽东栎幼苗根系形态结构特征的研究[D].西安:陕西师范大学,2012.
[8] 郑慧玲,赵成章,徐婷,段贝贝,韩玲,冯威.红砂根系分叉数和分支角度权衡关系的坡向差异.植物生态学报,2015,39(11):1062- 1070.
[9] Villordon A Q,Ginzberg I,Firon N .Root architecture and root and tuber crop productivity.Trends in Plant Science,2014,19(7):419- 425.
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[11] 韩玲,赵成章,徐婷,冯威,段贝贝,郑慧玲.张掖湿地芨芨草叶大小和叶脉密度的权衡关系.植物生态学报,2016,40(8):788- 797.
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[14] Glimsk?r A.Estimates of root system topology of five plant species grown at steady-state nutrition.Plant and Soil,2000,227(1/2):249- 256.
[15] Druille M,Cabello M N,Parisi P A G,Golluscio R A,Omacini M.Glyphosate vulnerability explains changes in root-symbionts propagules viability in pampean grasslands.Agriculture,Ecosystems & Environment,2015,202:48- 55.
[16] 刘丽娜.水曲柳根系径级和序级结构特性分析.山西林业科技,2015,44(1):18- 23.
[17] 罗久富,周金星,赵文霞,董林水,郑景明.围栏措施对青藏高原高寒草甸群落结构和稳定性的影响.草业科学,2017,34(3):565- 574.
[18] 高景,王金牛,徐波,谢雨,贺俊东,吴彦.不同雪被厚度下典型高山草地早春植物叶片性状、株高及生物量分配的研究.植物生态学报,2016,40(8):775- 787.
[19] 陈燕.大王马先蒿和三色马先蒿根形态可塑性及其生态学意义[D].北京:中国科学院大学,2013.
[20] 侯兆疆,赵成章,李钰,张茜,马小丽.不同坡向高寒退化草地狼毒株高和枝条数的权衡关系.植物生态学报,2014,38(3):281- 288.
[21] Westoby M,Wright I J.Land-Plant ecology on the basis of functional traits.Trends in Ecology & Evolution,2006,21(5):261- 268.
[22] Kleiman D,Aarssen L W.The leaf size/number trade-off in trees.Journal of Ecology,2007,95(2):376- 382.
[23] 蔡昆争,骆世明,段舜山.水稻根系在根袋处理条件下对氮养分的反应.生态学报,2003,23(6):1109- 1116.
[24] 梅莉,王政权,张秀娟,于立忠,杜英.施氮肥对水曲柳人工林细根生产和周转的影响.生态学杂志,2008,27(10):1663- 1668.
[25] McCarthy M C,Enquist B J.Consistency between an allometric approach and optimal partitioning theory in global patterns of plant biomass allocationFunctional Ecology,2007,21(4):713- 720.
[26] 薛丽华,段俊杰,王志敏,郭志伟,鲁来清.不同水分条件对冬小麦根系时空分布、土壤水利用和产量的影响.生态学报,2010,30(19):5296- 5305.
[27] 郑慧玲,赵成章,冯威,韩玲,徐婷,段贝贝.琵琶柴不同分支序级根系生物量分配格局的坡向差异.生态学杂志,2015,34(11):3065- 3071.
[28] 梅莉,王政权,韩有志,谷加存,王向荣,程云环,张秀娟.水曲柳根系生物量、比根长和根长密度的分布格局.应用生态学报,2006,17(1):1- 4.
[29] 严小龙,廖红,戈振扬,罗锡文.植物根构型特性与磷吸收效率.植物学通报,2002,17(6):511- 519.
[30] 单立山,李毅,董秋莲,耿东梅.红砂根系构型对干旱的生态适应.中国沙漠,2012,32(5):1283- 1290.
[31] 杜建会,刘安隆,董玉祥,胡绵友,梁杰,李薇.华南海岸典型沙生植物根系构型特征.植物生态学报,2014,38(8):888- 895.
[32] 罗维成,曾凡江,刘波,张利刚,宋聪,彭守兰,Arndt S K.疏叶骆驼刺根系对土壤异质性和种间竞争的响应.植物生态学报,2012,36(10):1015- 1023.
[33] 蒋礼学,李彦.三种荒漠灌木根系的构形特征与叶性因子对干旱生境的适应性比较.中国沙漠,2008,28(6):1118- 1124.
[34] Casper B B,Jackson R B.Plant competition underground.Annual Review of Ecology and Systematics,1997,28:545- 570.
[35] Bazzaz F A.Allocation of resources in plants:state of the science and critical questions//Bazzaz F A,Grace J,eds.Plant Resource Allocation.San Diego,CA:Academic Press,1997:1- 37.
[2] Kong X P,Zhang M L,de Smet I,Ding Z J.Designer crops:optimal root system architecture for nutrient acquisition.Trends in Biotechnology,2014,32(12):597- 598.
[3] Dannowski M,Block A.Fractal geometry and root system structures of heterogeneous plant communities.Plant and Soil,2005,272(1/2):61- 76.
[4] Malamy J E.Intrinsic and environmental response pathways that regulate root system architecture.Plant,Cell & Environment,2005,28(1):67- 77.
[5] Forde B,Lorenzo H.The nutritional control of root development.Plant and Soil,2001,232(1/2):51- 68.
[6] 宋清华,赵成章,史元春,杜晶,王继伟,陈静.不同坡向甘肃臭草根系分叉数和连接长度的权衡关系.植物生态学报,2015,39(6):577- 585.
[7] 夏菲.黄土高原子午岭辽东栎幼苗根系形态结构特征的研究[D].西安:陕西师范大学,2012.
[8] 郑慧玲,赵成章,徐婷,段贝贝,韩玲,冯威.红砂根系分叉数和分支角度权衡关系的坡向差异.植物生态学报,2015,39(11):1062- 1070.
[9] Villordon A Q,Ginzberg I,Firon N .Root architecture and root and tuber crop productivity.Trends in Plant Science,2014,19(7):419- 425.
[10] 朴顺姬,杨持,黄绍峰,宋明华.羊草种群密度与生长动态研究.植物生态学报,1997,21(1):60- 66.
[11] 韩玲,赵成章,徐婷,冯威,段贝贝,郑慧玲.张掖湿地芨芨草叶大小和叶脉密度的权衡关系.植物生态学报,2016,40(8):788- 797.
[12] Silvertown J,Charlesworth D.Introduction to plant population biology 4th ed.Oxford:Blackwell Science,2001.
[13] Minden V,Michael M.Ecosystem multifunctionality of coastal marshes is determined by key Plant traits.Journal of Vegetation Science Advances in Plant Community Ecology,2015,26(4):651- 662.
[14] Glimsk?r A.Estimates of root system topology of five plant species grown at steady-state nutrition.Plant and Soil,2000,227(1/2):249- 256.
[15] Druille M,Cabello M N,Parisi P A G,Golluscio R A,Omacini M.Glyphosate vulnerability explains changes in root-symbionts propagules viability in pampean grasslands.Agriculture,Ecosystems & Environment,2015,202:48- 55.
[16] 刘丽娜.水曲柳根系径级和序级结构特性分析.山西林业科技,2015,44(1):18- 23.
[17] 罗久富,周金星,赵文霞,董林水,郑景明.围栏措施对青藏高原高寒草甸群落结构和稳定性的影响.草业科学,2017,34(3):565- 574.
[18] 高景,王金牛,徐波,谢雨,贺俊东,吴彦.不同雪被厚度下典型高山草地早春植物叶片性状、株高及生物量分配的研究.植物生态学报,2016,40(8):775- 787.
[19] 陈燕.大王马先蒿和三色马先蒿根形态可塑性及其生态学意义[D].北京:中国科学院大学,2013.
[20] 侯兆疆,赵成章,李钰,张茜,马小丽.不同坡向高寒退化草地狼毒株高和枝条数的权衡关系.植物生态学报,2014,38(3):281- 288.
[21] Westoby M,Wright I J.Land-Plant ecology on the basis of functional traits.Trends in Ecology & Evolution,2006,21(5):261- 268.
[22] Kleiman D,Aarssen L W.The leaf size/number trade-off in trees.Journal of Ecology,2007,95(2):376- 382.
[23] 蔡昆争,骆世明,段舜山.水稻根系在根袋处理条件下对氮养分的反应.生态学报,2003,23(6):1109- 1116.
[24] 梅莉,王政权,张秀娟,于立忠,杜英.施氮肥对水曲柳人工林细根生产和周转的影响.生态学杂志,2008,27(10):1663- 1668.
[25] McCarthy M C,Enquist B J.Consistency between an allometric approach and optimal partitioning theory in global patterns of plant biomass allocationFunctional Ecology,2007,21(4):713- 720.
[26] 薛丽华,段俊杰,王志敏,郭志伟,鲁来清.不同水分条件对冬小麦根系时空分布、土壤水利用和产量的影响.生态学报,2010,30(19):5296- 5305.
[27] 郑慧玲,赵成章,冯威,韩玲,徐婷,段贝贝.琵琶柴不同分支序级根系生物量分配格局的坡向差异.生态学杂志,2015,34(11):3065- 3071.
[28] 梅莉,王政权,韩有志,谷加存,王向荣,程云环,张秀娟.水曲柳根系生物量、比根长和根长密度的分布格局.应用生态学报,2006,17(1):1- 4.
[29] 严小龙,廖红,戈振扬,罗锡文.植物根构型特性与磷吸收效率.植物学通报,2002,17(6):511- 519.
[30] 单立山,李毅,董秋莲,耿东梅.红砂根系构型对干旱的生态适应.中国沙漠,2012,32(5):1283- 1290.
[31] 杜建会,刘安隆,董玉祥,胡绵友,梁杰,李薇.华南海岸典型沙生植物根系构型特征.植物生态学报,2014,38(8):888- 895.
[32] 罗维成,曾凡江,刘波,张利刚,宋聪,彭守兰,Arndt S K.疏叶骆驼刺根系对土壤异质性和种间竞争的响应.植物生态学报,2012,36(10):1015- 1023.
[33] 蒋礼学,李彦.三种荒漠灌木根系的构形特征与叶性因子对干旱生境的适应性比较.中国沙漠,2008,28(6):1118- 1124.
[34] Casper B B,Jackson R B.Plant competition underground.Annual Review of Ecology and Systematics,1997,28:545- 570.
[35] Bazzaz F A.Allocation of resources in plants:state of the science and critical questions//Bazzaz F A,Grace J,eds.Plant Resource Allocation.San Diego,CA:Academic Press,1997:1- 37.