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Updated: Feb 10, 2026

Estimating Virus Production Rates in Aquatic Systems
Published on: September 22, 2010
[Estimation of net primary productivity in arid region based on coupling model.]
Hui Jin Yang1, Xiao Yu Li1, Li Juan Liu1
1Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China.
Abstract:
Net primary productivity (NPP), as the base for the research of matter recycling and energy flow in terrestrial ecosystem, is sensitive to the changes of environment and climate in arid region, and also is an important indicator of eco-environmental characteristics. Based on remote sensing (RS) and geographic information system (GIS), using meteorological data, eddy cova-riance data, Landsat 8 and MODIS data, this study coupled SEBAL model and light utility efficiency model to estimate the NPP of vegetation in Manas River Watershed, and the spatial pattern of NPP and the relationships between NPP and terrain factors (elevation and slope) were analyzed. Results showed that the estimated result of NPP in Manas River Watershed by coupling model was reasonable and could actually reflect the NPP of vegetation. The total annual NPP of vegetation and the mean annual NPP in Manas River Watershed in 2013 were 7066.72 Tg C·a-1 and 278.06 g C·m-2·a-1 respectively. With the variation of geomorphic type and land cover, the NPP changed remarkably from south to north in a trend of increase-decrease-increase-decrease pattern. The temporal variations of NPP were also obvious, with the NPP in July and August accounting for 52.2% of total annual NPP. With the increase of the elevation and slope, the mean annual NPP decreased as a whole with fluctuations induced by different land covers and environmental factors.
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