[1]XUE Xiaoyu,WANG Xiaoyun,DUAN Hanming,et al.Temporal and Spatial Changes of NPP and Its Causes in the Agricultural Pastoral Ecotone of Northern China[J].Research of Soil and Water Conservation,2021,28(02):190-197.
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Research of Soil and Water Conservation[ISSN 1005-3409/CN 61-1272/P] Volume:
28
Number of periods:
2021 02
Page number:
190-197
Column:
Public date:
2021-02-06
- Title:
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Temporal and Spatial Changes of NPP and Its Causes in the Agricultural Pastoral Ecotone of Northern China
- Author(s):
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XUE Xiaoyu1, WANG Xiaoyun1, DUAN Hanming1,2, XIE Yaowen
1
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(1.College of Earth and Environmental Sciences, Lanzhou University, Lanzhou 730000, China; 2.School of Land and Resources, China West Normal University, Nanchong, Sichuan 637002, China)
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- Keywords:
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agricultural pastoral ecotone of northern China; NPP; spatial change; climate change; human activities
- CLC:
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Q948
- DOI:
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- Abstract:
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In order to grasp the characteristics of multi-year spatiotemporal changes of vegetation NPP in the agricultural pastoral ecotone of northern China(APENC), the effects of climate change and human activities on vegetation NPP were studied. Based on VEGETATION-NDVI data, meteorological data and vegetation type data, the CASA model was used to estimate the vegetation NPP in the agricultural pastoral ecotone of Northern China. The Theil-Sen Median trend analysis, partial correlation analysis, residual analysis and other methods were used to analyze the relationship between NPP and climate factors and human activities in this area. The following conclusions are drawn. The annual average value of NPP in the study area from 1998 to 2016 was spatially high in the southwest and northeast, and low in the middle. The increase in NPP in the study area was significantly larger than the decrease in NPP. The annual precipitation was high in the southeast and low in the northwest, while the annual average temperature was high in the south and low in the north, high in the east and low in the west. During the study period, the annual precipitation had an overall increasing trend, and the annual average temperature in most areas had also increasing trend. There was a positive correlation between NPP and precipitation, and an obvious negative correlation with annual average temperature. The positive contribution of climate change and human activities to vegetation was significantly greater than its negative effect. Climate change is dominant in vegetation restoration. Human activities are the main factor of vegetation degradation. The main influencing factor of vegetation NPP in the APENC is climate change. The increase in precipitation promotes the restoration of vegetation; the increase in temperature and the enhancement of human activities lead to the degradation of vegetation. Therefore, reducing human activities and slowing down climate warming are of great significance to the restoration of vegetation in this area.