近20年陇东黄土高原耕地撂荒及其驱动力研究——以甘肃省平凉市崆峒区为例

Farmland Abandonment on the Loess Plateau of Longdong Region During the Past 20 Years and Its Driving Force: A Case Study of Kongtong District, Pingliang City, Gansu Province

为深入了解耕地撂荒的原因,保护耕地质量和数量,进而保证国家粮食安全和社会稳定,本文基于Landsat TM/OLI遥感数据与问卷调查数据,通过遥感影像解译和二元logistic回归模型研究了崆峒区耕地撂荒的时空分布和驱动力。结果表明:(1)1995—2015年崆峒区耕地撂荒面积增加5012.06 hm^2,其中前10年撂荒地面积增加了3221.13 hm^2,后10年撂荒地面积增加了1790.93 hm^2。(2)近20年以来,撂荒地主要集中在坡度为5°～20°的山区坡耕地。(3)影响崆峒区耕地撂荒的10个因子中,除家庭规模、耕地数量和耕地产量的回归系数较小外,其余因子都具有较大的回归系数。因此,在崆峒区社会经济因素是耕地撂荒的主要驱动力,务农机会成本上升等原因引起的耕地边际化是撂荒发生的根本原因,而劳动力析出是造成耕地撂荒的直接原因。

To understand the reason of cropland abandonment and protect quantity and quality of farmlands and then ensure national food security and social stabilization,based on the Landsat TM/OLI remote sensing data and data of questionnaire survey,the spatial and temporal distribution and driving force of cropland abandonment in Kongtong District was studied by satellite image interpretation and binary logistic regression model.The results showed that:(1)from 1995 to 2015,the area of abandoned farmland in Kongtong District increased by 5012.06 hm^2,which included 3221.13 hm^2 during the first ten years and 1790.93 hm^2 during the next decade;(2)in the past two decades,the abandoned farmland mainly distributed on the hillside field of mountainous region of slope between 5°and 20°;(3)among the 10 factors affecting farmland abandonment in Kongtong District,except the regression coefficients of the family size,the farmland quantity and the yield were relatively small;other factors had greater regression coefficients.Therefore,in Kongtong District,socioeconomic factors were the primary driving forces for the farmland abandonment,and the land marginalization,which was due to the drastic increase of farming opportunity cost,was the fundamental cause,while the direct factor for abandonment was the shrink of agricultural labor forces.