1. Soil nutrient availability regulated global carbon use efficiency.
- Author
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Zhang, Yangjian, Huang, Ke, Zhang, Tao, Zhu, Juntao, and Di, Yangping
- Subjects
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CARBON cycle , *FARMS , *PRIMARY productivity (Biology) , *GRASSLANDS , *REMOTE sensing - Abstract
Abstract The carbon use efficiency (CUE) is a core ecosystem parameter that determines the proportion of gross primary productivity (GPP) kept by an ecosystem after self-consumption. Its patterns along climates have been investigated to some extents. However, large uncertainty still exists, especially regarding its relationships with soil nutrients. The objective of this study was to evaluate the CUE variations along soil nutrient gradients by utilizing multi-sources of data for the global terrestrial ecosystem. The global terrestrial ecosystem CUE was calculated based on remote sensing modeled ecosystem productivity data, as well as in-situ observation data. The pattern analysis showed that global croplands and grasslands are distributed in nutrient-richer regions than forests. Along waning nutrients, GPP and net primary productivity (NPP) exhibit an overall increasing trend, while CUE declines. Within each biome, GPP and NPP decrease along enhanced nutrients for forests and grasslands, while CUE exhibits an opposite pattern. Based on worldwide collected field plot data, CUE also decreases along a weakened nutrient gradient. The strengthened ecosystem CUE pattern along enhanced nutrients as resulted from both model and field measurements data underscores the foremost significances of nutrients for ecosystem efficiency, also entails more comprehensive incorporations of nutrients in the future modeling studies. Highlights • The global remote sensing modeled results show that along decreasing nutrient, GPP and NPP exhibit an overall increasing trend while CUE decreases. Within the biome, GPP and NPP decrease along enhanced nutrient for forests and grassland. • The worldwide collected field plot data shows that the CUE of global terrestrial ecosystems also decreases along a weakened nutrient gradient. • This study integrated remote sensing and field measurements data and simultaneously concludes that the global terrestrial ecosystem CUE has a strengthened pattern along enhanced nutrients. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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