Spatial pattern of net primary productivity and its relationship with climatic factors in Hilly Red Soil Region of southern China: A case study in Taihe county, Jiangxi province

Abstract

Net primary productivity(NPP) and its responses to climate change stand one of the focuses of global change research. At the regional scale, it is significant to investigate the annual spatial variation and the impact of climatic factors on vegetation. Based on SPOT VEGETATION NDVI data, vegetation classification data and meteorological data, the spatiotemporal pattern on the NPP of Taihe county during 1988-2012 was simulated by CASA model.Then, the relationship between NPP and climatic factors was investigated deeply. The results showed that average annual NPP from 1988 to 2012 was 762 g C/m2· a in the study region.Spatial dimension is characterized by "high in the middle, but low in the east and west". There was a rising trend in the vegetation NPP during 1988-2012. The annual value fluctuated greatly.Mean NPP in the study area is 2.21×106g C/a. It can be found that vegetation NPP showed a weak positive correlation to annual precipitation, while it showed a significant negative correlation to annual average temperature. So, it can be concluded that temperature is the dominant climatic factor affecting vegetation NPP in the study region.