Control technique and system for run-off sand from agricultural land

目前，随着沙漠化的形成，土壤侵蚀已成为一个具有地球尺度的环境问题。特别是人口的爆炸性增长给发展中国家带来了压力，森林砍伐、农用地开发造成了土地侵蚀，地表径流成为一个大问题。水土流失是除农用地灾害外的环境问题，因此，掌握农用地水土流失的现状，建立约束控制体系具有十分重要的意义。在本研究中，考察了排除断层颗粒段推移质和浮沙的各种措施，并将其作为一种约束体系，在一定时期内进行了后续研究。(1)过去施工方法对浮沙的技术限制，使其成为浑水的因素。(2)在国内相关地区实地调研的基础上，对透水沉淀池的施工方法进行了规划设计。(3)考试楼的用水原因设计及现场楼、勘察的准备工作。(4)井下排水和砂层滤层的吹扫功能检测。(5)试验田表层土的物理特性和沉陷特性试验。(6)潜水对沉降池重力下沉的促进作用。(7)排水滤层的材料试验。(8)潜水能力下降及其措施检测。根据以上研究成果，编制了施工土砂外流控制方法手册。

The soil erosion becomes an environment problem with the earth scale with making a desert at present. Especially, the explosive increase of the population becomes pressure at the developing nation and the result of the forest felling, the agricultural land development causes ground erosion and the ground outflow becomes a big problem. Soil and sand outflow is taken up as the environment problem in addition to the agricultural land disaster.Therefore, it grasps the actual state of the soil and sand outflow from the agricultural land and to establish the restraint control system has very important meaning.In this study, it examined each measure to exclude bed load and floating sand in the fault grain part, it came out on the pollution watercourse and it made restraint a system.It implemented the following study in the given period. (1) Technical limit of the method of construction in the past to the floating sand which becomes the factor of muddy water. (2) The plan and the design of the permeable settling basin method of construction which is based on the spot investigation in the domestic related area. (3) The water reason design for the examination building and the preparation of the spot building and the investigation. (4) The examination of the purge function of under-drainage and the sandy filtration layer. (5) The physical characteristic and the sinking characteristic experiment of the topsoil in the examination field. (6) The promotion operation of the glavitational sinking of settling basin by under-drainage. (7) The material experiment of the under-drainage filtration layer. (8) The under-drainage ability decline and the measure examination of it. It made a manual about the soil and sand outflow control method of construction from above results.