定量评价人类活动对吕梁山植被NPP的影响

Quantitative Evaluation of the Impact of Human Activities on Net Primary Productivity of Vegetation in Lüliang Mountains

为研究2000-2019年吕梁山植被NPP的时空分布格局,定量评价人类活动对其影响,采用改进的CASA模型估算2000-2019年吕梁山实际NPP(NPP_(A)),结合周广胜模型估算得到的潜在NPP(NPP_(P))计算人类活动导致的NPP损失(NPP_(H)),并利用人类活动相对影响贡献率指数(RICI)来定量评价人类活动对植被NPP的贡献率,同时分析土地利用类型变化对植被NPP_(A)的影响。结果表明:吕梁山NPP_(A)和NPP_(H)分别呈增加和减少趋势,NPP_(A)整体呈东南向西北减少,NPP_(H)呈东南向西北增加;土地利用变化主要集中在林地、农田、草地、水体之间,林地和农田面积增加会使NPP_(A)总量增加,林地转为其他类型和草地转为农田则会造成NPP_(A)减少;人类活动对吕梁山NPP的贡献率为51.80%,表明人类活动在吕梁山NPP变化中占主导因素。研究结果可为吕梁山生态环境的修复、保护和可持续发展提供科学依据。

To investigate the spatial and temporal distribution patterns of vegetation net primary productivity(NPP)in the Lüliang Mountains from 2000 to 2019,and to quantitatively assess the impact of human activities on these patterns,this study employs an enhanced CASA model to estimate the actual NPP(NPP_(A))for the region.By integrating the potential NPP(NPP_(P))estimated using Zhou Guang-sheng’s model,we calculate the NPP loss(NPP_(H))attributed to human activities.In association with the Relative Impact Contribution Index(RICI),we quantify the influence of human activities on vegetation NPP and analyze how changes in land use types affect NPP_(A).Results reveal that NPP_(A)in the Lüliang Mountains generally exhibited a decreasing trend from southeast to northwest,while NPP_(H)displayed an increasing trend in the same direction.Changes in land use primarily affected forest land,farmland,grassland,and water bodies.Increasing areas of forest land and farmland led to a rise in total NPP_(A),whereas converting forest land to other uses and transforming grassland into farmland resulted in a decrease in NPP_(A).Human activities account for 51.80%of the observed changes in NPP,highlighting their significant role in altering NPP in the Lüliang Mountains.These findings provide a scientific foundation for the restoration,protection,and sustainable management of ecological environment in the Lüliang Mountains.