基于遥感数据的若尔盖地区2001—2015年植被生育期特征及其对气候变化的响应分析
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摘要
遥感NDVI(归一化植被指数)数据能较好地反映植被生长变化情况,已广泛应用于多尺度植被物候监测。基于MODIS卫星每16 d的NDVI遥感数据,通过时间序列滤波软件TIMESAT重建了若尔盖地区2001—2015年NDVI时间序列,提取出植被3个关键生育期信息—植被生育期起始时间、植被生育期长度和生育期内NDVI峰值;分析了影响植被生育期的关键气候因子。结果表明:1)2001—2015若尔盖地区植被平均生育期起始时间提前,生育期长度延长,NDVI峰值无明显变化。2)植被平均生育期在空间分布上无明显递变规律;随海拔梯度升高,植被生育期起始时间推迟,生育期长度缩短,NDVI峰值减小。3)温度是影响若尔盖地区植被生育期的主要气候因素,4、5月积温升高促进植被生育期起始时间提前(相关系数|R|=0.79);9、10月积温升高有利于植被生育期结束时间推后,使得生植被育期长度延长(相关系数|R|=0.73);从植被生育期起始至NDVI峰值出现时间段内积温的升高也使得植被NDVI峰值升高(相关系数|R|=0.68)。4)植被NDVI与SPI(标准化降水指数)相关性不高,若尔盖地区植被生长对降水变化不敏感。研究结果较为真实地反映了2001—2015年若尔盖区域植被的生育期特征及其对气候变化的响应,其方法可应用于遥感监测区域范围内植被变化特征。
NDVI(normalized difference vegetation index) can reflect the changes of vegetation growth. It has been widely used to monitor multiscale vegetation growth conditions. Based on MODIS remote sensing data, the time series of NDVI from 2001 to 2015 in Zoigê area were reconstructed by filtering software TIMESAT, and three key vegetation growth properties were extracted: The start of vegetation growth period, the length of vegetation growth period and the maximum NDVI value. The key climatic factors affecting the vegetation growth period were analyzed.The results showed that: 1) The average start time of vegetation growth period increased, and the average length of vegetation growth period prolonged, while and the maximum NDVI values had no significant changes from 2001 to 2015. 2) The average vegetation growth properties had no obvious regular pattern of change in spatial distribution.As the elevation increased, the start of vegetation growth period postponed, the length of vegetation growth period shortened visibly, and the maximum of NDVI did not change obviously. 3) Temperature is the main factor that impacted vegetation growth period in Zoigê area. Increasing accumulated temperature in April and May could advance the start time of vegetation growth period. The average length of vegetation growth period would be longer with the higher accumulated temperature in September and October. The increase of accumulated temperature from the start time of growth period to the time of the maximum NDVI also increased the maximum value of NDVI. 4) The correlation between NDVI and SPI was not significant. Therefore, the vegetation in Zoigê area had low dependence on precipitation.The findings showed the changes of vegetation growth period in Zoigê area and their response to climate over the past 15 years. The methods used in this paper can provided a useful tool for remote sensing monitoring of vegetation characteristics at large scales.
NDVI(normalized difference vegetation index) can reflect the changes of vegetation growth. It has been widely used to monitor multiscale vegetation growth conditions. Based on MODIS remote sensing data, the time series of NDVI from 2001 to 2015 in Zoigê area were reconstructed by filtering software TIMESAT, and three key vegetation growth properties were extracted: The start of vegetation growth period, the length of vegetation growth period and the maximum NDVI value. The key climatic factors affecting the vegetation growth period were analyzed.The results showed that: 1) The average start time of vegetation growth period increased, and the average length of vegetation growth period prolonged, while and the maximum NDVI values had no significant changes from 2001 to 2015. 2) The average vegetation growth properties had no obvious regular pattern of change in spatial distribution.As the elevation increased, the start of vegetation growth period postponed, the length of vegetation growth period shortened visibly, and the maximum of NDVI did not change obviously. 3) Temperature is the main factor that impacted vegetation growth period in Zoigê area. Increasing accumulated temperature in April and May could advance the start time of vegetation growth period. The average length of vegetation growth period would be longer with the higher accumulated temperature in September and October. The increase of accumulated temperature from the start time of growth period to the time of the maximum NDVI also increased the maximum value of NDVI. 4) The correlation between NDVI and SPI was not significant. Therefore, the vegetation in Zoigê area had low dependence on precipitation.The findings showed the changes of vegetation growth period in Zoigê area and their response to climate over the past 15 years. The methods used in this paper can provided a useful tool for remote sensing monitoring of vegetation characteristics at large scales.
引文
[1]Korner C,Basler D.Phenology under global warming[J].Science,2010,327(5972):1461.
[2]Walker J,de Beurs K M,Wynne R H.Phenological response of an arizona dryland forest to short-term climatic extremes[J].Remote Sensing,2015,7(8):10832-10855.
[3]Li Z W,Wang Z Y,Brierley G,et al.Shrinkage of the ZoigêSwamp and changes to landscape connectivity,QinghaiTibet Plateau[J].Catena,2015,126:155-163.
[4]Xia C F,Li J,Liu Q H.Review of advances in vegetation phenology monitoring by remote sensing[J].Journal of Remote Sensing,2013,17(1):1-16.
[5]Hou Meiting,Zhao Haiyan,Wang Zheng,et al.Vegetation responses to climate change by using the satellite-derived normalized difference vegetation index:A review[J].Climatic&Environmental Research,2013,18(3):353-364.[侯美婷,赵海燕,王筝,等.基于卫星遥感的植被NDVI对气候变化响应的研究进展[J].气候与环境研究,2013,18(3):353-364.]
[6]Dunn A H,de Beurs K M.Land surface phenology of North American mountain environments using moderate resolution imaging spectroradiometer data[J].Remote Sensing of Environment,2011,115(5):1220-1233.
[7]Walker J J,de Beurs K M,Wynne R H.Dryland vegetation phenology across an elevation gradient in Arizona,USA,investigated with fused MODIS and Landsat data[J].Remote Sensing of Environment,2014,144(1):85-97.
[8]Hou Xuehui,Niu Zheng,Gao Shuai.Phenology of forest vegetation in Northeast of China in ten years using remote sensing[J].Spectroscopy and Spectral Analysis,2014,34(2):515-519.[侯学会,牛铮,高帅.近十年中国东北森林植被物候遥感监测[J].光谱学与光谱分析,2014,34(2):515-519.]
[9]Piao S L,Cui M D,Chen A P,et al.Altitude and temperature dependence of change in the spring vegetation green-up date from 1982 to 2006 in the Qinghai-Xizang Plateau[J].Agricultural and Forest Meteorology,2011,151(12):1599-1608.
[10]Zhang G L,Zhang Y J,Dong J W,et al.Green-up dates in the Tibetan Plateau have continuously advanced from 1982 to2011[J].Processing of the National Academy of Science of the United States of America,2013,110(11):4309-4314.
[11]Song Chunqiao,Ke Linghong,You Songcai,et al.Comparison of three NDVI time-series fitting methods based on TIMESAT-Taking the grassland in Northern Tibet as case[J].Remote Sensing Technology&Application,2011,26(2):147-155.[宋春桥,柯灵红,游松财,等.基于TIMSAT的3种时序NDVI拟合方法比较研究--以藏北草原为例[J].遥感技术与应用,2011,26(2):147-155.]
[12]Li Ming,Wu Zhengfang,Du Haibo,et al.Growing-season trends determined from SPOT NDVI in Changbai mountains,China,1999-2008[J].Scientia Geographica Sinica,2011,31(10):1242-1248.[李明,吴正方,杜海波,等.基于遥感方法的长白山地区植被物候期变化趋势研究[J].地理科学,2011,31(10):1242-1248.]
[13]Martiny N,Camberlin P,Richard Y,et al.Compared regimes of NDVI and rainfall in semi-arid regions of Africa[J].International Journal of Remote Sensing,2006,27(23):5201-5223.
[14]Wang X H,Piao S L,Philippe C,et al.Spring temperature change and its implication in the change of vegetation growth in North America from 1982 to 2006[J].Processing of the National Academy of Science of the United States of America,2011,108(4):1240-1245.
[15]Qing Qingtao,Hou Meiting,Wang Mingtian,et al.Influences of meteorological conditions on growing period of kentucky bluegrass in Zoigêgrassland[J].Chinese Journal of Agrometeorology,2010,31(1):69-73.[卿清涛,侯美婷,王明田,等.气象条件对若尔盖草地早熟禾生育期的影响[J].中国农业气象,2010,31(1):69-73.]
[16]Xu K,Yang D W,Yang H B,et al.Spatio-temproal variation of drought in China during 1961-2012:A climate perspective[J].Journal of Hydrology,2015,526(3):253-264.
[17]Richard Y,Martiny N,Fauchereau N,et al.Interannual memory effects for spring NDVI in semi-arid South Africa[J].Geophysical Research Letters,2008,35(350):195-209.
[18]Song Chunqiao,You Songcai,Ke Linghong,et al.Spatiotemporal variation of vegetation phenology in the Northern Tibetan Plateau as detected by MODIS remote sensing[J].Chinese Journal of Plant Ecology,2011,35(8):853-863.[宋春桥,游松财,柯灵红,等.藏北高原植被物候时空动态变化的遥感监测研究[J].植物生态学报,2011,35(8):853-863.]
[19]Shen M G,Zhang G X,Nan C,et al.Increasing altitudinal gradient of spring vegetation phenology during the last decade on the Qinghai-Tibetan Plateau[J].Agricultural and Forest Meteorology,2014,189/190:71-80.
[2]Walker J,de Beurs K M,Wynne R H.Phenological response of an arizona dryland forest to short-term climatic extremes[J].Remote Sensing,2015,7(8):10832-10855.
[3]Li Z W,Wang Z Y,Brierley G,et al.Shrinkage of the ZoigêSwamp and changes to landscape connectivity,QinghaiTibet Plateau[J].Catena,2015,126:155-163.
[4]Xia C F,Li J,Liu Q H.Review of advances in vegetation phenology monitoring by remote sensing[J].Journal of Remote Sensing,2013,17(1):1-16.
[5]Hou Meiting,Zhao Haiyan,Wang Zheng,et al.Vegetation responses to climate change by using the satellite-derived normalized difference vegetation index:A review[J].Climatic&Environmental Research,2013,18(3):353-364.[侯美婷,赵海燕,王筝,等.基于卫星遥感的植被NDVI对气候变化响应的研究进展[J].气候与环境研究,2013,18(3):353-364.]
[6]Dunn A H,de Beurs K M.Land surface phenology of North American mountain environments using moderate resolution imaging spectroradiometer data[J].Remote Sensing of Environment,2011,115(5):1220-1233.
[7]Walker J J,de Beurs K M,Wynne R H.Dryland vegetation phenology across an elevation gradient in Arizona,USA,investigated with fused MODIS and Landsat data[J].Remote Sensing of Environment,2014,144(1):85-97.
[8]Hou Xuehui,Niu Zheng,Gao Shuai.Phenology of forest vegetation in Northeast of China in ten years using remote sensing[J].Spectroscopy and Spectral Analysis,2014,34(2):515-519.[侯学会,牛铮,高帅.近十年中国东北森林植被物候遥感监测[J].光谱学与光谱分析,2014,34(2):515-519.]
[9]Piao S L,Cui M D,Chen A P,et al.Altitude and temperature dependence of change in the spring vegetation green-up date from 1982 to 2006 in the Qinghai-Xizang Plateau[J].Agricultural and Forest Meteorology,2011,151(12):1599-1608.
[10]Zhang G L,Zhang Y J,Dong J W,et al.Green-up dates in the Tibetan Plateau have continuously advanced from 1982 to2011[J].Processing of the National Academy of Science of the United States of America,2013,110(11):4309-4314.
[11]Song Chunqiao,Ke Linghong,You Songcai,et al.Comparison of three NDVI time-series fitting methods based on TIMESAT-Taking the grassland in Northern Tibet as case[J].Remote Sensing Technology&Application,2011,26(2):147-155.[宋春桥,柯灵红,游松财,等.基于TIMSAT的3种时序NDVI拟合方法比较研究--以藏北草原为例[J].遥感技术与应用,2011,26(2):147-155.]
[12]Li Ming,Wu Zhengfang,Du Haibo,et al.Growing-season trends determined from SPOT NDVI in Changbai mountains,China,1999-2008[J].Scientia Geographica Sinica,2011,31(10):1242-1248.[李明,吴正方,杜海波,等.基于遥感方法的长白山地区植被物候期变化趋势研究[J].地理科学,2011,31(10):1242-1248.]
[13]Martiny N,Camberlin P,Richard Y,et al.Compared regimes of NDVI and rainfall in semi-arid regions of Africa[J].International Journal of Remote Sensing,2006,27(23):5201-5223.
[14]Wang X H,Piao S L,Philippe C,et al.Spring temperature change and its implication in the change of vegetation growth in North America from 1982 to 2006[J].Processing of the National Academy of Science of the United States of America,2011,108(4):1240-1245.
[15]Qing Qingtao,Hou Meiting,Wang Mingtian,et al.Influences of meteorological conditions on growing period of kentucky bluegrass in Zoigêgrassland[J].Chinese Journal of Agrometeorology,2010,31(1):69-73.[卿清涛,侯美婷,王明田,等.气象条件对若尔盖草地早熟禾生育期的影响[J].中国农业气象,2010,31(1):69-73.]
[16]Xu K,Yang D W,Yang H B,et al.Spatio-temproal variation of drought in China during 1961-2012:A climate perspective[J].Journal of Hydrology,2015,526(3):253-264.
[17]Richard Y,Martiny N,Fauchereau N,et al.Interannual memory effects for spring NDVI in semi-arid South Africa[J].Geophysical Research Letters,2008,35(350):195-209.
[18]Song Chunqiao,You Songcai,Ke Linghong,et al.Spatiotemporal variation of vegetation phenology in the Northern Tibetan Plateau as detected by MODIS remote sensing[J].Chinese Journal of Plant Ecology,2011,35(8):853-863.[宋春桥,游松财,柯灵红,等.藏北高原植被物候时空动态变化的遥感监测研究[J].植物生态学报,2011,35(8):853-863.]
[19]Shen M G,Zhang G X,Nan C,et al.Increasing altitudinal gradient of spring vegetation phenology during the last decade on the Qinghai-Tibetan Plateau[J].Agricultural and Forest Meteorology,2014,189/190:71-80.
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