稻虾共作快速发展背景下潜江耕地时空变化特征分析

Spatiotemporal Characteristics of Cropland in Qianjiang City under the Development of Rice-Crayfish Integrated

虾稻共作综合种养模式近年来在长江中下游地区快速发展,探索虾稻共作对农业土地利用的影响,对于科学调控虾稻田发展、确保粮食和生态双安全具有重要意义。该研究以虾稻共作模式发源地——湖北潜江市为研究区域,利用空间分析和破碎度指数方法,分析虾稻共作模式快速推广下潜江市农业土地利用时空格局变化。结果表明:(1)近20年来,耕地时空格局变化过程是以园林办事处(主城区)为中心的建设用地向西至广华镇、南至杨市镇不断扩张,耕地转为新增建设用地达28.64 km2,约18.59 km2耕地转换为水域;(2)耕地格局呈现破碎化,主要由城市发展过程中建设用地扩张占用耕地,以及虾稻田快速发展后造成;(3)虾稻田主要由水田转换而来,部分旱地及水域也转换为虾稻田。虾稻田的不断扩张,特别是旱地和水域转换为虾稻田,一定程度上带来耕地破碎化。因此,在我国农业劳动力不足、农民收入不高和种地积极性不强等因素下,未来虾稻田种植模式对耕地利用具有较好的潜力和空间,但也需要重点关注虾稻共作模式的可持续发展,重点基于水田发展虾稻田种养模式。

The purposes of this study are to explore the impact of the rapid development of rice-crayfish integrated on the utilization of cropland, and how to balance the development of rice-crayfish fields with the food and ecological security. The results show that:(1) The change process of the spatio-temporal pattern of cropland has been expanding westward to Guanghua town and southwest to Yangshi town with the center of the Yuanlin town in the past 20 years. Cropland was converted into newly added construction land for 28.64 km^2 and about 18.59 km^2 water body;(2) The fragmentation of cropland is mainly caused by the expansion of construction land occupation of cropland in urban development, and the special planting characteristics of rice-crayfish fields rapid development;(3) Rice-crayfish fields are mainly converted from paddy fields. A part of dry land and water are also converted into rice-crayfish fields. The continuous expansion of rice-crayfish fields, especially the conversion of dry land and water to rice-crayfish fields, has brought about a certain degree of fragmentation of cropland. In conclusion, reducing farmland fragmentation is not the only development direction of agricultural production, especially under the factors of serious fragmentation of cropland, serious lack of rural agricultural power, low income of farmers and weak enthusiasm for farming in South China, rice-crayfish fields planting mode has a good potential and space in the agricultural development of South China.