吉首市耕地地力现状与利用对策分析

耕地地力的高低直接影响到农业的可持续发展和粮食安全。基于测土配方施肥调查结果,分析吉首市耕地地力现状,探讨其可持续发展策略。结果表明,全市高产耕地面积仅26%,74%的耕地为中、低产土壤,尤其是在旱地土中,中低产土壤占的比例较大。吉首市耕地以三级地分布面积最大,为2189.7 hm2,占耕地总面积的19.8%。园地只在三至七级地中分布,其中以六、七级地分布面积较大,分别为2221.5 hm2和3062.1 hm2,占园地总面积的26.5%和36.6%。耕地和园地中低产田以瘠薄培肥型和障碍层次型中低产田面积较大,分别为6165.1 hm2与6418.2 hm2,分别占障碍型土壤面积的36.3%和37.8%。旱地土耕作层浅化问题较严重,耕地土壤养分失调、缺素较普遍,也是当前吉首市土壤存在的主要问题。提出了针对性地消除土壤障碍因子,加速吉首市种植业结构战略性调整,实现粮食和经济作物同耕地地力的合理配置,有利于促进农业产业结构与资源、环境容量相互协调和农村经济可持续稳定发展。

The status and exploitation strategies of cropland quality in Jishou County, Hunan Province

The productivity of cropland has direct influences on agricultural sustainable development and food security. This study evaluated the quality of cropland in Jishou County, Hunan Province according to national protocols of cropland quality measurement. The results showed that 26% and 74% the cropland soil has medium and low productivity, respectively. Specifically, cropland with medium and low productivity is mainly in dryland. Among the cropland, the area of grade three productivity was the largest (2189.7 hm2, 19.8% of total cropland area). In contrast, garden fields had a productivity grades from three to seven. The area of Grades 6 and 7 garden field were 2221.5 (26.5%) and 3062.1 (36.6%) hm2 respectively. Results also indicates that the types with larger area were the types of unfertile and obstruction layer. Areas of these two types were 6165.1 hm2 and 6418.2 hm2, respectively. They were 36.3% and 37.8% respectively, of the total area of the soils with obstruction factors. Thin tillage layers in dryland and unbalanced nutrients and nutrients deficiency in top soils were the main problems for croplands in Jishou. To improve productivity of the cultivated land, measures include eliminating the obstruction factors and speeding up the adjustment of cropping pattern in accordance with cropland productivity.