Evaluation of Vegetation Characteristics over Qinghai- Xizang Plateau Simulated by A Vegetation Dynamic Model

Abstract

In this study， performances of NCAR Community Land Surface Model CLM （version 4.5） coupled with dynamic vegetation and carbon-nitrogen model （CN-DV） in representing the observed vegetation characteristics of satellite over the Qinghai-Xizang Plateau （QXP） during historical period 1981—2000 were evaluated by comparing with remote sensing datasets of leaf area index （LAI） and coverage fraction.It was shown CLM4.5-CNDV can generally reproduce the spatial distribution of LAI， coverage fractions and their linear trends shown in the satellite data， but LAI was seriously overestimated due to the significantly overestimated tree coverage， and underestimated grass coverage as well.The 1~2 month lag shown both in LAI and precipitation may suggest that the simulated LAI bias could also be caused by the bias of atmospheric forcing which come from 18 model of CMIP5.The spatial distribution of LAI linear trend had a great agreement with precipitation and 10-cm soil moisture， implying that the surface hydrological variations are the key factors to QXP vegetation change.

Keywords

• qinghai-xizang plateau
• vegetation coverage fraction
• global vegetation dynamic model （gvdm）
• clm4.5-cndv