基于MODIS的广西植被NPP时空分异及驱动力分析

Spatial and Temporal Variability in the Net Primary Production and Its Driving Factors Base on MODIS Data in Guangxi, China

为探索广西植被净初级生产力(net primary productivity,NPP)变化规律及驱动因子,利用遥感数据、土壤数据和海拔高程数据,运用统计学分析方法,对比分析不同城市、土壤、海拔高度的植被NPP变化。结果表明:(1)2000—2015年广西植被NPP值(以碳累积量计)在578.51~870.48 g·m^-2·a^-1波动变化,总体呈下降趋势。梧州、防城港的植被NPP值较高。(2)广西6.45%区域的植被NPP处于重度变异状态,65.25%区域的植被NPP处于中度变异,28.30%区域的植被NPP处于轻度变异状态。(3)植被NPP对气温降水的变化响应不够显著。(4)红壤、石灰土、粗骨土地区的植被NPP呈下降趋势,而砖红壤地区的植被NPP呈增加趋势。(5)不同海拔高度的植被NPP差异较大,总体变化呈“增加-下降-增加-下降”的趋势。

To explore general regularity of vegetation net primary productivity change and driving factor in Guangxi,based on the remote sensing data and Soil data and digital elevation model data,statistical methods are used to compare the vegetation net primary productivity change trend in different cities,soil and altitude.The results showed that:(1)The vegetation net primary productivity fluctuated between 578.51-870.48 g·m^-2·a^-1 from 2000 to 2015 in Guangxi,showing a downward trend.The vegetation net primary productivity in Wuzhou and Fangchenggang was high.(2)The vegetation net primary productivity in 6.45%of the area of Guangxi was in severe variation state,and 65.25%of the area of vegetation net primary productivity was in moderate variation,28.30%of the area of vegetation net primary productivity was in mild variation.(3)Vegetation net primary productivity response to temperature and precipitation was not significantly enough.(4)Vegetation net primary productivity of Red earth,Limestone soil,Skeletal soil showed a declined trend,but that of Latosol increased.(5)The net primary productivity at different altitudes varied greatly,and the overall change trend is increase-decline-increase-decline.