开发利用对泥石流滩地土壤肥力特性的影响

龙洞沟泥石流滩地剖面结构和土壤物理结构较差 ,砂石化现象严重 ;土壤微团聚体数量较少 ,粒级间比例不合理 ;土壤养分除全钾极丰富外 ,其它大部分养分都处于缺乏或极缺状态。通过开发利用 ,其表土层结构特性和养分状况得到显著改善 :砾石含量由 63 .0 3～ 70 .78%减少到 3 9.66～ 57.62 % ,粉粒和粘粒含量由 2 6.75～ 3 1.89%增加到 3 0 .54～41.93 % ;有机质由 7.1～ 10 .8gkg- 1提高到 15.8～ 2 6.9gkg- 1;全氮由 1.2 0～ 1.40gkg- 1提高到 1.50～ 1.93gkg- 1;全磷由0 .46～ 0 .57gkg- 1提高到 0 .48～ 0 .79gkg- 1;有效氮由 47.2 2～ 56.67mgkg- 1提高到 79.3 9～ 119.46mgkg- 1;有效磷由 2 .2 1～ 4.69mgkg- 1提高到 5.58mgkg- 1;有效钾由 2 9.84～ 40 .3 6mgkg- 1提高到 51.89～ 89.3 6mgkg- 1。不同利用模式的改良作用不同 ,依次为 :菜园地 >苹果 +蔬菜地 >苹果园地 >苹果 +花椒地 >花椒园地 >荒滩地

Effects of Exploitation on the Soil Fertility Properties of Debris Flow Waste-shoal Land in the Longdong Ravine,Sichuan Province

The soil fertility properties of debris flow waste-shoal land were studied. The results indicated that the topsoil structure and nutrient were greatly improved by land exploitation. 1. The volume of gravel in the topsoil were decreased from 63.03-70.78% to 39.66-57.62% and the clay and silt increased from 26.75-31.89% to 30.54-41.93%. 2. The contents of organic matter in the topsoil were increased from 0.71-1.08% to 1.58-2.69% and total N from 1.20-1.40g kg -1 to 1.50-1.93g kg -1 ,total P from 0.46-0.57g kg -1 to 0.48-0.79g kg -1 ,available N from 47.22-56.67mg kg -1 to 79.39-119.46mg kg -1 ,and available P from 2.21-4.69mg kg -1 to 5.58 mg kg -1 ,and available K from 29.84-40.36mg kg -1 to 51.89-89.36mg kg -1 . 3. The characteristics of soil fertility are in the order:vegetable garden > land of apple tree and vegetable > apple orchard > land of apple tree and Chinese prickly ash tree > land of Chinese prickly ash tree > fallow land.