生态退耕背景下黄河流域耕地变化与农业生产和生态环境关系研究

THE RELATIONSHIP BETWEEN CULTIVATED LAND CHANGE AND AGRICULTURAL PRODUCTION, ECOLOGICAL ENVIRONMENT IN THE YELLOW RIVER BASIN UNDER THE BACKGROUND OF GRAIN FOR GREEN PROGRAM

关键词:  生态退耕  耕地变化  格兰杰因果检验  空间自相关  黄河流域

Key words:  grain for green program  cultivated land change  Granger causality test  spatial autocorrelation  Yellow River Basin

摘要:

目的 分析生态退耕背景下黄河流域耕地的时空变化特征，探讨黄河流域不同区域耕地变化与农业生产和生态环境的相互关系，旨在为黄河流域农业绿色发展和耕地利用政策提供借鉴。方法 文章基于2000—2020年黄河流域连续土地利用数据，利用面板格兰杰因果检验和双变量空间自相关量化耕地变化与农业生产、生态环境之间的动态因果及空间交互关系。结果 （1）2000—2020年黄河流域年均减少耕地69.53万 hm²，还林还草是耕地主要减少去向，2020年和2004年是退耕还林还草高峰年，中上游是退耕还林还草重点区；（2）从格兰杰因果检验来看，下游地区退耕还林还草对农业生产和生态环境没有显著影响，上游地区长期退耕还林还草对农业产值增加有利，中游粮食产量和生态系统服务供给低的地区退耕还林还草更多，中上游生态退耕对生态环境有显著促进作用；（3）从空间自相关结果来看，下游地区退耕与农业生产和生态环境的空间分布不具有一致性，黄土高原南部和太行山附近退耕还林还草与生态环境指标呈高—高集聚，鄂尔多斯高原地区退耕与农业产值呈小范围高—高集聚。结论 退耕还林还草是黄河流域耕地变化的重要原因，退耕还林还草规模与农业生产和生态环境之间的空间关系异质性明显，且在部分区域存在因果关系，不同区域应当针对具体问题提出不同用地策略。

Abstract:

This study is intends to analyze the temporal and spatial change characteristics of cultivated land in the Yellow River Basin under the background of the Grain for Green program, and explore the relationship between cultivated land change and agricultural production, ecological environment in different regions of the Yellow River Basin, so as to provide reference for the green development of agriculture and the utilization policy of cultivated land in the Yellow River Basin. Based on the continuous land use data of the Yellow River Basin from 2000 to 2020, the dynamic causality and spatial interaction between cultivated land change and agricultural production, ecological environment were quantified by using panel Granger causality test and bivariate spatial autocorrelation analysis. The results were showed as follows. Firstly, the annual reduction of cultivated land in the Yellow River Basin was 0. 695 3 million hm² from 2000 to 2020, and returning farmland to forest and grassland was the main destination of cultivated land reduction. 2020 and 2004 were the peak years of returning farmland to forest and grassland, and the middle and upper reaches were the key areas of returning farmland to forest and grassland. Secondly, according to the Granger causality test, the conversion of farmland to forest and grassland in the lower reaches had no significant impact on agricultural production and ecological environment. The long-term conversion of farmland to forest and grassland in the upper reaches was beneficial to the increase of agricultural output value. There were more areas with low grain yield and ecosystem service supply in the middle reaches, and the Grain for Green program in the middle and upper reaches had a significant role in promoting the ecological environment. Thirdly, according to the results of spatial autocorrelation, the spatial distribution of returning farmland to forest and grassland in the lower reaches was inconsistent with that of agricultural production and ecological environment. The returning farmland to forest and grassland and ecological environment indicators in the south of the Loess Plateau and near the Taihang Mountain showed High-High agglomeration, and the returning farmland and agricultural output value in the Ordos Plateau showed small-scale High-High agglomeration. In conclude, returning farmland to forest and grassland is a significant reason for the change of cultivated land in the Yellow River Basin. The spatial relationship between the scale of returning farmland to forest and grassland, and agricultural production and ecological environment is heterogeneous, and there is a causal relationship in some regions. Therefore, different land use strategies should be put forward according to specific problems in different regions.