期刊名称：ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences
印刷版ISSN：2194-9042
电子版ISSN：2194-9050
出版年度：2009
卷号：XXXVIII-8/W3
页码：239
出版社：Copernicus Publications
摘要：The monitoring of terrestrial carbon dynamics is important in studies related with global climate change. This paper reports the inter-annual variability of Net Primary Productivity (NPP) from 1981-2000 derived using observations from NOAA-AVHRR data using GloPEM model. The GloPEM model is based on physiological principles and uses the production efficiency concept, in which the canopy absorption of photosynthetically active radiation (APAR) is used with a conversion "efficiency" to estimate gross primary production (GPP). NPP derived from GloPEM model over India showed maximum NPP about 3000 gCm-2year-1 in west Bengal and lowest up to 500 gCm-2year-1in Rajasthan. The India averaged NPP varied from 1084.7 gCm-2year-1 to 1390.8 gCm-2year-1in the corresponding years of 1983 and 1998 respectively. The regression analysis of the 20 year NPP variability showed significant increase in NPP over India (r=0.7, F=17.53, p < 0.001). The mean rate of increase was observed as 10.43 gCm-2year –1. Carbon fixation ability of terrestrial ecosystem of India is increasing with rate of 34.3 TgC annualy (t= 4.18, p < 0.001). The estimated net carbon fixation over Indian landmass ranged from from 3.56 PgC (in 1983) to 4.57 PgC (in 1998). Grid level temporal correlation analysis showed that agricultural regions are the source of increase in terrestrial NPP of India. Parts of forest regions (Himalyan in Nepal, north east India) are relatively less influenced over the study period and showed lower or negative correlation (trend). Finding of the study would provide important input in understanding the global change associated with vegetation activities as a sink for atmospheric carbon dioxide
