江西亚热带风沙化土地的生态特征及防护对策

江西亚热带风沙化土地的机械组成以粗沙为主,粒径在1-0.25 mm的沙占65.37-78.38%。养分极其贫乏,有机质含量仅为0.05-0.20%,速效氮、磷、钾分别为14.2-19.9ppm,9.4-160.1ppm,80.0-87.0ppm。风沙活动强烈。保水能力差,雨后连晴数日,沙层含水率即降到凋萎湿度以下。植被稀疏,物种缺乏。建群种蔓荆群落的层次不分明,最小面积6.25 m²,常见种仅1-2种,隐芽植物占100%.因其恶劣的生态条件,防护体系建设中应补充灌溉、施肥。同时,扩大引种范围,解决种源缺乏问题。防扩体系由封育带,阻沙带和林带组成。阻沙带使用蔓荆灌丛结合草方格的方法,形成滞沙环境。林带的组成树种可选白花泡桐、湿地松等。

The Ecological chaiacteristics of Blownsand Land and Protective Measures in Subtropic Area of Jiangxi Province

The blownsand lands in Jiangxi Province are char-acterized by coarse sand grain size,low organic matter content,strong blowing sand actuvity,low water holding capacit,less plant species and sparse vegetation.The sand grain large than 0.25mm is 65.37-78.38%,organic matter content is 0.05-0.20%,available N,P,and K are 14.2-19.9ppm,9.4-160.lppm,and 80.0-87.Oppm rsdpec-lively.The minimum area of Vitex trifolia community is 6.25m²,the species number in the community is 1-2,whereas the cryptophyte in the life form spectrum is 100%.Because of the unfavorable eco-logical condition,the following protective measures should be taken into account:1) application of fertilizer and watering in dry seaspm.2) introducting plant species from all over the world and selecting the excellent species for protecting system;3) erecting straw checkerboard,planting Vitex trifolia within the straw checkerboard,and forming a sand-depositing environment.The protecting system are composed of protecting belt,sand-depositing belt,and protective forest belt.