宁夏南部山区环境特征与生态修复——以彭阳县古城乡半阴湿土石质黄土梁峁区为例

Environmental Features and the Ecology Regeneration in a Mountainous Region in South Ningxia——A Case Study in a Semi-dank and Terrene-lithoid Loess-hilly Region in Gucheng Township,Pengyang County

在不同的地质地貌条件下,土壤侵蚀强度表现不同。因此,根据不同的立地条件,采取不同的治理措施是生态修复成败与否的关键。由于生态修复的各种生物和工程措施是建立在不同的地质地貌条件下,因此本文以彭阳县古城乡半阴湿土石质黄土梁峁区为研究区,通过野外现场调查,对研究区的立地条件进行了划分。在此基础上,选择不同的树种组合和造林模式,采用成熟的工程措施和栽培技术,确定该研究区的生态修复组合模式,进而对研究区的生态修复提出合理化建议。

Pengyang County （35°41＇～36°17＇N, 106°32＇～106°58＇E） is located in the southern part of Ningxia Hui Autonomous Region, China, in the county it belongs to the continental monsoon climate, the county is a temperate semiarid region, the annual temperature and the frost-flee period vary in ranges of 7.4～8.5℃ and 140～170 days respectively. Located in the southwestern part of Pengyang County, Gucheng Township is the main region in the study, where the annual precipitation varies in a range of 450～550 mm, there are 13 natural villages and 4 993 households, the population is 24 562, and the agricultural population density is 102.7 person/km^2 ; the annual per capita income of farmers is 1 022 yuan; the total land area is 2.29×10^4 hm^2, the area under cultivation is 6 778 hm^2, in which the area of irrigated lands is 666 hm^2, the per capita land area is 0.28 hm^2, and the per mu yield of cereals is 107.5 kg. Although the per capita farmland area is relatively large, most of the farmlands are sloped. Therefore, it is important to implement the project of withdrawing from farming to afforesting and grass planting. Soil erosion intensity is different under the different geological and morphological conditions, so the different measures should be taken in regenerating the ecology based on the different local conditions. In this paper, a case study on regenerating the ecology in a semi-dank and terrene-lithoid loess-hilly region in Pengyang County, South Ningxia Hui Autonomous Region, is carried out based on the field investigation and the local conditions. Finally, some measures are put forward： （1） The hillsides should be closed to facilitate afforestation in the southwestern terrene-lithoid mountainous regions by combining the migration, selecting the water-conserving tree species, and implementing the project of withdrawing from farming to afforesting and grass planting in the sloped farmlands so as to achieve the ecological regeneration through afforestation; （2） The different tree species and afforestation ways should be selected based on the local conditions; （3） the different ecological regeneration modes should be taken in the different regions.