内蒙古荒漠草原植被NPP时空变化及气候因子分析:以四子王旗为例

Spatio-temporal dynamics of vegetation net primary productivity and its response to climate change in desert steppe,Inner Mongolia:A case study in Siziwang Banner

基于遥感数据和气象数据,利用光能利用率模型(CASA),对典型荒漠草原四子王旗1987—2016年植被NPP进行测算,分析NPP时空变化及其与年均气温和年降水量等气候因子的相关性。结果表明:1)1987—2016年四子王旗植被NPP值为144.52g/(m^2·年)(C),植被类型地带性分布差异明显,空间上表现出南高北低的分布特征;2)1987—2016年四子王旗植被NPP总体呈现出增长趋势,年际波动为3.09~3.69Tg(C);3)研究区植被NPP与年均气温和年降水量呈显著正相关关系,且与年降水量相关系数更高,表明年降水量是影响荒漠草原区植被NPP的主要气候因子。通过研究荒漠草地植被NPP时空分布及其与气候因子的关系,有助于认识荒漠草原陆地生态系统对气候变化的响应。

Based on remote sensing data and climate data,the vegetation net primary productivity of typical desert grassland from 1987 to 2016 in Siziwang Banner was measured by CASA model.The spatio-temporal variation of NPP and its correlation with climate factors such as annual temperature and yearly rainfall were analyzed.The results showed that:1)The annual mean value of NPP was 144.52 g/(m^2·a)(C)during the period.The zonal distribution of vegetation type was obviously different,showing high southeast and low northwest in space;2)The annual change of vegetation NPP was obvious and the range of fluctuation was in 3.09-3.69 Tg(C),which showed an increasing trend from 1987 to 2016 in Siziwang banner;3)There was a significant positive correlation between vegetation NPP and annual temperature and yearly rainfall,and a higher correlation coefficient between vegetation NPP and yearly rainfall,indicating that precipitation was the main climatic factor affecting vegetation NPP in desert steppe.The investigation of the spatial and temporal distribution of NPP and its relation with climate factors in desert grassland helped to understand the response of terrestrial ecosystem to climate change in desert grassland.