Spatio-temporal variation of carbon and water use efficiency of different land cover in the Poyang Lake Basin and their correlations with climate factors

The Poyang Lake Basin is a prominent carbon sink functional area in China. Understanding the spatio-temporal differentiation of different land covers ecosystem carbon use efficiency（CUE） and water use efficiency（WUE） in the Poyang Lake Basin and their responses to meteorological factors is of great significance to clarify regional ecological functions and carbon-water cycle under the context of climate change. Based on the latest MODIS products, land cover data and meteorological observations during 2000-2014, the spatio-temporal variations of CUE and WUE of different land covers in the Poyang Lake Basin and their correlations with precipitation, temperature and sunshine duration were investigated by using the methods of trend analysis and correlation analysis. Results of this research show that: 1) the average annual CUE and WUE in the Poyang Lake Basin were 0.458 and 0.682 gC/kgH2O, respectively. For different land cover types, the values of CUE descended in the order of grassland > paddy field > other wood