Abstract
Grassland covers 54% of the Tibetan Plateau (TP) and suffered overgrazing and degradation problems during past decades. To alleviate these problems, a series of policy measures have been implemented during recent two decades and inevitably caused changes of the grassland. To this end, this study quantitatively analyzed the grassland changes and the effects of reduced grazing intensity, and identified the hot plots of grassland degradation in the TP during 2000–2019. The grassland status was indicated by the Fractional Vegetation Cover in the green grass period (GP), i.e., FVCGP, and its changes and spatial variations were detected by analyzing the FVCGP trends and their distribution, using the Mann–Kendal, Sen’s Slope, and ArcGIS buffering methods, and data of the MOD13Q1 Collection 6 products and other sources. The results showed that 62.12% of the grasslands were significantly increased in the FVCGP, and 28.34% had no apparent changes. The remaining 9.54% of the grassland significantly decreased in the FVCGP, mainly occurring in the areas nearby roads, rivers, and lakes, and distributed mostly in a point pattern. Of the total FVCGP decreased grassland area, 27.03% was clustered and identified as the hot plots of grassland degradation in six main regions. Decreased grazing intensity and increased precipitation contributed to the increase of grassland FVC in the TP, while local overgrazing could be the main cause of the FVC decrease. To strength the grassland restoration in the TP, the government supports and supervision should be enhanced to further mitigate the grassland pressure of animal grazing, particularly in the hot plot areas of degradation.
Highlights
Published: 7 January 2021Grassland covers about 40% of the global land surface [1], provides vital ecosystem services [1,2], and plays an essential role in food security, biodiversity maintenance, and sustainable development [3,4]
Temperature is normally below 0 ◦ C is normally below and annual precipitation below mm, the was mostly and annual precipitation below 200 mm, the grass period (GP) was mostly less than four months, andless than four months, and mean FVCGP was lower than 25%
The hot plots of grassland degradation in the Tibetan Plateau (TP) were identified by quantifying trends of the annual average Fractional Vegetation Cover (FVC) in the green grass period (FVCGP ), and the causal factors of grassland changes were detected to support regional grassland management
Summary
Grassland covers about 40% of the global land surface [1], provides vital ecosystem services [1,2], and plays an essential role in food security, biodiversity maintenance, and sustainable development [3,4]. During recent decades, half of the global grasslands were degraded due to anthropogenic and natural factors [2,3,5]. Grassland degradation has become the main threat to the ecological security of the TP [8,13,14]. The grassland degradation in the TP occurred mostly during 1980s to the early of 21st century, as mainly caused by anthropogenic factors, overgrazing, and shows high spatial heterogeneity [8,14,15,16,17]. Some studies reported that 50.9% of the grassland in
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: International journal of environmental research and public health
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
