永州新田石漠化坡地生态修复技术探究

Study on ecological restoration technology for rocky sloping fields in Xintian County of Yongzhou City

在永州新田县梘头镇石漠化程度比较严重的两个村子,选定总计20 km 2石灰岩裸露坡地作为试验区域,运用基质覆盖和客土等方式进行土壤改良。试验区种植以棱角山矾为主体,混栽金钱柳,山核桃,黄花槐,白三叶,紫花苜蓿等乔灌木和植被的植物群落,种植周期为3年。期间,对不同覆盖和客土方式的试验区的主要种植树种的生长状态及对应的土壤理化特性进行检测及分析。结果表明,在永州石漠化地区的生态修复中,通过基质覆盖和客土可以改变土壤的pH值,增加土壤孔隙度,减少土壤容重,提高土壤肥力,促进植物生长,提高生态修复的效率。采用白三叶、紫花苜蓿植被覆盖具有采用基质覆盖的相近效能。利用当地的茅草与环保基质的混合覆盖,能有效地改善土壤容重,增强植物的抗旱水平。

The limestone bareness sloping fields with total area of 20 km 2 in two villages in Liantou Town of Xintian County with seriously stony desertification were selected as the test fields.The soil on this district was improved by coverage and soil replacement with matrix.Symplocos Tetragona was the main tree species planted in the improved fields and companionately being planted with Cyclocarya paliurus,Carya cathayensis,Sophora xanthantha,Trifolium repens and Medicago sativa.The planting period was 3 years.During this period,the growing status of planted tree species and various physiochemical indexes of planting soil were tested and analyzed.It was indicated that coverage and soil replacement with matrix could alter the pH value of soil,increase the soil porosity,improve the soil fertility,promote plant growth and accelerate the ecological restoration.Coverring with Trifolium repens and Medicago sativa performed similarly.It was also be found that the mixed coverage with local thatch and matrix could reduce the soil bulk density and improve the drought resisting ability of the plant.