Research shows temporospatial patterns of human appropriation of net primary production in Central Asia grasslands

Grasslands are widespread in Central Asia and serve important economic and ecological functions, due to lack of water resources, grassland ecosystems are considered highly sensitive and vulnerable to human disturbance and climatic change in this region.
Quantifying and mapping grassland human appropriation of net primary production (HANPP) is vital for the sustainable use of grasslands. However, grazing process was not effectively considered in previous studies, leading to biased results.
A group of researchers from China’s State Key Laboratory of Desert and Oasis Ecology effectively considered the grazing process of Central Asia, presented a better understanding of the temporospatial patterns of HANPP in Central Asia grasslands and provided data to support the rational use of grassland resources.
The study used the Biome-Biogeochemical Cycles grazing model to estimate HANPP and explore its temporospatial patterns in Central Asia grasslands from 1979 to 2012. The result showed that HANPP was 47gC/m2 /yr, which represented 34% of Central Asia grassland potential net primary production and HANPP efficiency was 70% in this region. Interannual variations in HANPP and HANPP as a percentage of NPP were significantly positively related to grazing intensity. Interannual variation in HANPP efficiency was negatively related to grazing intensity.
HANPP showed strong regional variation. High HANPP values were mainly observed in temperate grassland and some forest meadow. Low HANPP values were mainly observed in desert grassland and some forest meadow. The spatial pattern of HANPP percentage NPP was similar to that of HANPP in this region. Interannual variations in HANPP were mainly determined by population change and economic development. Spatial patterns of HANPP were primarily determined by grazing intensity and grazing system.
The results of this study was published on Ecological Indicators, entitled Temporospatial patterns of human appropriation of net primary production in Central Asia grasslands.