摘要
深入了解青藏高原草地生产力与草畜平衡状态的变化,是青藏高原生态屏障建设和生态环境保护的基础。利用遥感植被指数和叶面积指数产品,基于VIP生态水文过程模型,模拟分析了青藏高原2000—2018年间草地生产力的时空格局,并结合同期农牧业统计资料,分析了青藏高原县域尺度草畜平衡状态的变化。结果表明:青藏高原草地多年平均净初级生产力(NPP)为158.4 g C·m^(-2)·a^(-1);近20年来草地生产力上升趋势明显,显著上升面积的比例为44.7%。气候变暖、降水量增加、草本植物生长期延长和大气CO2浓度升高是青藏高原草地生产力提高的主要驱动因素。基于草场产量估算的青藏高原平均理论载畜量为1.17 SU·hm^(-2),年增长率为0.011 SU·hm^(-2)。2000年以来青藏高原草地超载情况总体趋于好转,严重超载县的面积比例已降至20%以下,其中超载程度较严重的地区,畜牧业的维持和发展主要依靠作物秸秆补饲。研究结果可为区域农牧业结构调整和生态环境保护提供科学依据。
An in-depth understanding of variations in grassland productivity and forage-livestock balance is the basis of ecological barrier construction and ecosystem conservation in the Qinghai-Tibetan Plateau.Using an ecohydrological process-based model VIP with remotely sensed vegetation index and leaf area index,we simulated the spatial and temporal variations of grassland productivity in the Tibetan Plateau in 2000-2018.The variations in the status of forage-livestock balance at the county level were analyzed,combining with agriculture and animal husbandry statistics in the same period.The results showed that the mean annual net primary productivity(NPP)of grassland in the Tibetan Plateau was 158.4 g C·m^(-2)·a^(-1),which had increased significantly in the past 20 years,with a significant increase in 44.7%of the total area.Climate warming,increased precipitation,prolonged growing season,and elevated carbon dioxide concentration were main driving forces for grassland productivity.The mean theoretical livestock carrying capacity estimated based on pasture yield was 1.17 SU·hm^(-2),with a growth rate of 0.011 SU·hm^(-2).The situation of overgrazing in the Tibetan Plateau had generally improved since 2000.The proportion of counties with severe overgrazing had dropped to less than 20%.In areas with more severe overgrazing,animal husbandry’s maintenance and development mainly relied on supplementation of crop straw.The results could provide a scientific basis for regional agricultural and animal husbandry structural adjustment and environmental protection.
作者
莫兴国
刘文
孟铖铖
胡实
刘苏峡
林忠辉
MO Xing-guo;LIU Wen;MENG Cheng-cheng;HU Shi;LIU Su-xia;LIN Zhong-hui(Key Laboratory of Water Cycle and Related Land Surface Processes,Institute of Geographic Sciences and Natural Resources Research,Chinese Academy of Sciences,Beijing 100101,China;College of Resources and Environment/Sino-Danish Center,University of Chinese Academy of Sciences,Beijing 100049,China)
出处
《应用生态学报》
CAS
CSCD
北大核心
2021年第7期2415-2425,共11页
Chinese Journal of Applied Ecology
基金
中国科学院战略性先导科技专项(XDA20040301)资助。
关键词
草地生产力
理论载畜量
超载程度
VIP模型
grassland productivity
theoretical livestock carrying capacity
overgrazing degree
VIP ecohydrological dynamic model
