[1]DENG Xingyao,YAO Junqiang,LIU Zhihui,et al.Spatiotemporal Dynamic Change Characteristics of Evapotranspiration in Tianshan Mountains from 2000 to 2014[J].Research of Soil and Water Conservation,2017,24(04):266-273.
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Research of Soil and Water Conservation[ISSN 1005-3409/CN 61-1272/P] Volume:
24
Number of periods:
2017 04
Page number:
266-273
Column:
Public date:
2017-08-28
- Title:
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Spatiotemporal Dynamic Change Characteristics of Evapotranspiration in Tianshan Mountains from 2000 to 2014
- Author(s):
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DENG Xingyao1,2,3, YAO Junqiang4, LIU Zhihui2,3, LIU Yang1,2,3
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1. College of Resources and Environment Science, Xinjiang University, Urumqi 830046, China;
2. Institute of Arid Ecology and Environment, Xinjiang University, Urumqi 830046, China;
3. Key Laboratory of Oasis Ecology of Education Ministry, Xinjiang University, Urumqi 830046, China;
4. Institute of Desert Meteorology, China Meteorlogical Administration, Urumqi 830002, China
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- Keywords:
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evapotranspiration; MODIS; the Tianshan Mountains; precipitation; trend analysis
- CLC:
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P426.2
- DOI:
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- Abstract:
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Using MODIS ET data of actual surface evapotranspiration products that were concentrated from 2000 to 2014, we used variable coefficients, the Theil-Sen median trend analysis, Mann-Kendall test, and Hurst index, to investigate the spatial pattern of evapotranspiration, spatial heterogeneity, characteristics of time variation, and future trends considering the Tianshan Mountains. The results showed as the following. (1) Evapotranspiration over the entire region was very high from 2000 to 2014, and the area with evapotranspiration greater than 400 mm accounts for 49.172% of the total area. Affected by precipitation, evapotranspiration is high in the west and north, but low in the east and south. Affected by land cover types, areas with higher value of evapotranspiration (more than 400 mm) mainly included the mountain forestland and grassland, but the area with low value of evapotranspiration (less than 200 mm) concentrated in sparse vegetation region. Evapotranspiration data decreased in the order: cropland > forestland > grassland > sparse vegetation. (2) The degree of variation in evapotranspiration over the past 15 years for the entire region is not obvious, but shows a slight fluctuation. The proportion of areas with slight fluctuations accounts for 45.140% of the total area. Among them, the region of high fluctuation was caused by the change of land cover types. (3) The value of evapotranspiration over the past 15 years for the entire region varied from 305 mm to 387 mm and shows changes in the fluctuations with a weakly decreasing trend with the change rate of -2.911 6 mm/year. An analysis based on the pixel scale also shows a mainly decreasing trend, the area with decrease trend accounts for 83.022% of the total area. This decrease trend of regional evapotranspiration was caused by the decrease of precipitation. (4) The Hurst index average of evapotranspiration for the entire region is 0.747. The area with Hurst index greater than 0.5 accounts for 86.382% of the total area. The change trend of evapotranspiration in the future for the entire region is mainly towards a persistent decrease and this area accounts for 69.888% of the total area. However, the trend of changes for 15.589% of the area cannot be determined.