基于MOD16数据,计算作物缺水指数(Crop Water Stress Index,CWSI),结合汾河流域气象站点数据、植被指数数据和土地利用数据,采用差值法、线性趋势法和相关分析法,分析汾河流域2000—2021年干旱时空变化特征。结果表明:(1)CWSI能有效监...基于MOD16数据,计算作物缺水指数(Crop Water Stress Index,CWSI),结合汾河流域气象站点数据、植被指数数据和土地利用数据,采用差值法、线性趋势法和相关分析法,分析汾河流域2000—2021年干旱时空变化特征。结果表明:(1)CWSI能有效监测汾河流域旱情,其与10 cm土壤相对湿度呈显著负相关。(2)汾河流域CWSI空间分布差异明显,呈现出南湿北旱的特点。(3)汾河流域CWSI年际变化较为平稳,而月变化波动较大,5月CWSI达到年内峰值。(4)汾河流域不同生长期内干旱情况差异显著,生长季前期(4—5月)特旱区占汾河流域总面积的48.55%;生长季中期(6—8月)基本全域无旱;生长季后期(9—10月),仅11.17%的地区发生干旱。(5)不同土地利用类型干旱程度不同,CWSI从小到大依次为:林地(0.686)<草地(0.749)<耕地(0.751)<未利用地(0.758)<城镇(0.765)。本研究结果可为汾河流域旱情监测和抗旱决策的制定提供科学数据支撑。展开更多
A robust tree-ring-width chronology was developed from two Pinus tabulaeformis sampling sites in the source of the Fenhe River,Shanxi Province,China.Based on the tree-ring-width indices,a 157-year long Palmer Drought ...A robust tree-ring-width chronology was developed from two Pinus tabulaeformis sampling sites in the source of the Fenhe River,Shanxi Province,China.Based on the tree-ring-width indices,a 157-year long Palmer Drought Severity Index(PDSI) was reconstructed,which explains 53.7% of the variance of the modeled PDSI over the common period 1957-2008.The drought periods in the study area include 1914-1931 and 1970 to the present,whereas the wet periods were 1866-1892 and 1932-1969.The drought of 1914-1931 was a severe long-lasting drought with a low inter-annual variability,and the drought of 1970-2009 was an overall long-term drought with a high inter-annual variability.The period of 1866-1892 is a continuously wet period with a low inter-annual variability and the period of 1932-1969 is an overall long-term wet period with a high inter-annual variability.The reconstructed PDSI series in the source of the Fenhe River shows synchronous variations with the regional drought/wetness indices.Spatial correlation analyses indicate that the higher correlations lie exclusively in the Fenhe River Basin.This indicates that the reconstructed PDSI has regional representativeness and can represent the drought history of the entire Fenhe River Basin to some extent.Furthermore,the reconstructed PDSI matches with the variability of the per unit yield of summer grain crops in Shanxi Province very well and they have significant correlation.From a long-term perspective the reconstructed PDSI series could supply scientific and valuable information to the water resources management and then help the sustainable development in agricultural production,economic development,and ecosystem balance.展开更多
文摘基于MOD16数据,计算作物缺水指数(Crop Water Stress Index,CWSI),结合汾河流域气象站点数据、植被指数数据和土地利用数据,采用差值法、线性趋势法和相关分析法,分析汾河流域2000—2021年干旱时空变化特征。结果表明:(1)CWSI能有效监测汾河流域旱情,其与10 cm土壤相对湿度呈显著负相关。(2)汾河流域CWSI空间分布差异明显,呈现出南湿北旱的特点。(3)汾河流域CWSI年际变化较为平稳,而月变化波动较大,5月CWSI达到年内峰值。(4)汾河流域不同生长期内干旱情况差异显著,生长季前期(4—5月)特旱区占汾河流域总面积的48.55%;生长季中期(6—8月)基本全域无旱;生长季后期(9—10月),仅11.17%的地区发生干旱。(5)不同土地利用类型干旱程度不同,CWSI从小到大依次为:林地(0.686)<草地(0.749)<耕地(0.751)<未利用地(0.758)<城镇(0.765)。本研究结果可为汾河流域旱情监测和抗旱决策的制定提供科学数据支撑。
基金supported by National Natural Science Foundation of China (Grant Nos. 40901060,41023006,and 40890051)National Basic Research Program of China (Grant No. 2010CB833405)the State Key Laboratory of Loess and Quaternary Geology and the Sino-Swedish Tree-Ring Research Center (SISTRR) Contribution
文摘A robust tree-ring-width chronology was developed from two Pinus tabulaeformis sampling sites in the source of the Fenhe River,Shanxi Province,China.Based on the tree-ring-width indices,a 157-year long Palmer Drought Severity Index(PDSI) was reconstructed,which explains 53.7% of the variance of the modeled PDSI over the common period 1957-2008.The drought periods in the study area include 1914-1931 and 1970 to the present,whereas the wet periods were 1866-1892 and 1932-1969.The drought of 1914-1931 was a severe long-lasting drought with a low inter-annual variability,and the drought of 1970-2009 was an overall long-term drought with a high inter-annual variability.The period of 1866-1892 is a continuously wet period with a low inter-annual variability and the period of 1932-1969 is an overall long-term wet period with a high inter-annual variability.The reconstructed PDSI series in the source of the Fenhe River shows synchronous variations with the regional drought/wetness indices.Spatial correlation analyses indicate that the higher correlations lie exclusively in the Fenhe River Basin.This indicates that the reconstructed PDSI has regional representativeness and can represent the drought history of the entire Fenhe River Basin to some extent.Furthermore,the reconstructed PDSI matches with the variability of the per unit yield of summer grain crops in Shanxi Province very well and they have significant correlation.From a long-term perspective the reconstructed PDSI series could supply scientific and valuable information to the water resources management and then help the sustainable development in agricultural production,economic development,and ecosystem balance.
