Artemisia ordosica BTOPMC model CASA LAI Loess Plateau MODIS Pinus engelmannii Carr Poyang Lake Basin Robinia pseudoacacia L. and Pinus tabulaeformis Carr. mixed plantations afforestation afforestation ecosystem base flow chlorophyll fluorescence climate fluctuation composted pine bark different climatic conditions dye tests ecosystem model empirical statistics energy partitioning evapotranspiration evapotranspiration (ET) forest cover fresh pine sawdust heat dissipation probes human activity in situ calibration living brush mattress net primary productivity peat moss