退耕还林还草前后植被净初级生产力动态及其对环境变化的响应评估:以陕北黄土高原为例  

Assessment of the dynamics of vegetation net primary productivity and its response to environmental changes before and after the Grain for Green Project:A case study form the Loess Plateau of Northern Shaanxi

作　　者：李岩 商冉 曲衍波[3] LI Yan;SHANG Ran;QU Yanbo(Land Reserve Centre of Ji′nan,Ji'nan 250100,Shandong,China;School of Resource and Environment Engineering,Shandong Agriculture and Engineering University,Ji'nan 250100,Shandong,China;School of Public Management,Shandong University of Finance and Economic,Ji'nan 250014,Shandong,China)

机构地区：[1]济南市土地储备中心,山东济南250100 [2]山东农业工程学院资源与环境工程学院,山东济南250100 [3]山东财经大学公共管理学院,山东济南250014

出　　处：《水利水电技术（中英文）》2023年第6期156-166,共11页Water Resources and Hydropower Engineering

基　　金：国家自然科学基金面上项目(42077434);山东省高等学校“青年创新团队发展计划”项目(2019RWG016)。

摘　　要：【目的】为揭示陕北黄土高原退耕还林还草前后的植被净初级生产力(NPP)时空演变规律及其对环境变化的响应状态,【方法】基于土地利用模型分析陕北黄土高原1980—2020年的土地利用变化特征,采用改进的CASA模型揭示NPP时空动态,并结合情景分析法探讨了环境变化对NPP的影响。【结果】(1)1980—2020年陕北黄土高原耕地、水体和未利用地减少,林地、草地和建设用地增加;退耕还林还草前的综合土地利用动态度为2.24%,9086.25 km^(2)的土地参与转移,以未利用地转出为草地为主;退耕还林还草后的综合土地利用动态度为22.15%,12340.88 km^(2)的土地参与转移,以耕地转出为林地、草地和建设用地为主。(2)以2000年(退耕还林还草)为界,研究区40 a间NPP先减后增,整体增加了271.66 gC·m^(-2)·a^(-1);空间上呈现南高北低的分布特征,整个研究期内98.54%的区域出现了NPP增加的现象;不同土地利用类型多年NPP均值大小排列为:林地>草地>耕地>建设用地>水体>未利用地。(3)退耕还林还草实施前,土地利用、NDVI、降雨和气温变化对陕北黄土高原NPP变化的贡献率分别为0.14%、47.22%、42.07%和10.57%;退耕还林还草实施后,NDVI变化对该地区NPP的变化贡献率高达85.42%,土地利用、降雨和气温变化的贡献率较低,分别为0.33%、9.67%和4.58%。【结论】随着退耕还林还草的实施,陕北黄土高原土地利用整体变化速率加快;NPP年均值增加、高值区范围扩大,生态状况得到明显改善;NDVI变化成为该地区NPP变化的主导因素。[Objective]In order to reveal the spatial and temporal evolution of vegetation net primary productivity(NPP)before and after the Grain for Green Project in the Loess Plateau of Northern Shaanxi and its response characteristic to environmental changes,[Methods]this study analyzed the land use change characteristics in the Loess Plateau of Northern Shaanxi from 1980 to 2020 by using the land use model,revealed the spatial and temporal dynamics of vegetation NPP by using the improved CASA model,and explored the influence of environmental changes on vegetation NPP by combining the scenario analysis method.[Results](1)From 1980 to 2020,the cultivated land,water body and bared land in the Loess Plateau of Northern Shaanxi decreased,and the forestland,grassland and construction land increased.The dynamic degree of comprehensive land use before returning cultivated land to forest land and grassland is 2.24%,and 9086.25 km^(2) of land is involved in the transfer,mainly in the transfer of bared land to grassland.The comprehensive land use dynamic degree after returning cultivated land to forest land and grassland was 22.15%,and 12340.88 km^(2) of land participated in the transfer,and mainly in the transfer of the cultivated land to forest land,grassland and construction land.(2)Taking the year 2000(the Gain for Green)as the boundary,the NPP in the study area decreased first and then increased during the 40 years,with an overall increase of 271.66 gC·m^(-2)·a^(-1).The spatial distribution of NPP was high in the south and low in the north.During the whole study period,98.54%of the area showed an increase in NPP.The annual average NPP of different land use types was as follows:forest land grassland cultivated land construction land water body bared land.(3)Before the implementation of the Gain for Green Project,the contribution rates of land use,NDVI,precipitation and air temperature to NPP change in the Loess Plateau of Northern Shaanxi were 0.14%,47.22%,42.07%and 10.57%,respectively.After the implementation of the Gain fo

关 键 词：退耕还林还草 植被净初级生产力 CASA模型 环境变化 陕北黄土高原 

分 类 号：Q948[生物学—植物学]