重庆市长寿区旱改水潜力评价与优化研究

EVALUATION AND OPTIMIZATION OF DRYLAND-TO-PADDY POTENTIAL IN CHANGSHOU DISTRICT, CHONGQING

关键词:  耕地利用  土地整治  旱地改水田  空间分布  潜力评价

Key words:  cultivated land utilization  land consolidation  dryland-to-paddy  spatial distribution  potential evaluation

摘要:

目的 文章以重庆市长寿区为例，对其旱地改水田潜力进行测算，以期提高耕地质量，促进耕地内部结构调整和占补平衡，保障地区粮食安全和生态系统安全。方法 基于2010—2018年旱改水空间分布特征研究，构建旱改水适宜性评价模型，该模型涵盖地形条件、土壤条件、耕作条件3个评价维度，包括海拔高程、地形坡度、表层土壤质地等10个评价指标。然后利用模型评价旱改水整治潜 力，并识别整治的障碍因素，最后基于评价结果，提出旱改水的整治措施建议。结果 （1）2010—2018年长寿区旱地改水田整体集中度较高，主要分布在北部和中部地区，其中，密度最高的乡镇是海棠镇、云台镇和葛兰镇。（2）总的来说，重庆市长寿区旱地改水田整体适宜性不高，高度适宜和中度适宜改为水田的旱地面积分别为159.81hm²、8 115.64hm²，两者占全域总面积的25.22%，这些地块主要分布在区域中部、北部的石堰镇、葛兰镇、云台镇等乡镇；勉强适宜和不适宜改为水田的旱地占比为74.78%，这些地块限制性因素较多，难以改造为水田。结论 综上，未来长寿区可通过改造有效土层厚度低、地形坡度较陡、田块面积小、灌溉保证率低等障碍因素推动耕地旱改水工作。

Abstract:

This article takes the Changshou district of Chongqing as an example to estimate its potential for dryland converting to paddy field, with a view to improving the quality of arable land, promoting the adjustment of the internal structure and the balance of occupancy and compensation of arable land, and ensuring regional food security and ecosystem security. Based on the research on the spatial distribution characteristics of dryland-to-paddy from 2010 to 2018, this study constructed a dryland-to-paddy suitability evaluation model, covering 3 evaluation dimensions, terrain conditions, soil conditions, and farming conditions, and including 10 evaluation indicators such as altitude, terrain slope, and surface soil texture. After that, it used the model to evaluate the potential of dryland-to-paddy conversion and identify obstacles to conversion. Finally, based on the results, it put forward suggestions on the improvement measures for dryland-to-paddy conversion. The results were showed as follows. (1) From 2010 to 2018, the concentration of drylands converted to paddy fields in Changshou district was relatively high, and the map spots were mainly distributed in the northern and central regions. Among them, the towns with the highest map spot density were Haitang Town, Yuntai Town and Gelan Town. (2) On the whole, the suitability of changing drylands to paddy fields in Changshou district of Chongqing was not high. The areas of drylands that were highly suitable and moderately suitable for changing to paddy fields were 159.81 hm² and 8 115.64 hm² respectively, which accounting for 25.22% of the total area. These plots were mainly distributed in Shiyan town, Gelan town and other towns in the central and northern parts of the region. The proportion of drylands that was barely suitable and unsuitable to be converted into paddy fields accounted for 74.78%. These plots had many restrictive factors and were difficult to be converted into paddy fields. To sum up, in the future, Changshou district of Chongqing city can promote the work of arable land conversion from dryland-to-paddy by reforming obstacles such as low effective soil thickness, steep terrain slope, small field area, and low irrigation guarantee rate.