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1、开沟耕作与垄作区田在少雨地带于栽培田地内创造多数小蓄水区,是有效的保持水分和防止风及水侵蚀的有效方法.这个方法早在30年代在美国就已经发展起来了.创造小蓄水区是先开沟起垄,然后在沟内隔一定距离设一个小土坡,有的用人工操作或者机械作业.试验证明,人工操作是不耐侵蚀的,主要因为不能准确地按等高线起垄,水易于冲刷渠道而集中一个地点,水漫顶而垄遭到破坏.在热带地区试验证明,单独开沟作垄而不进行区田(tying)虽然垄是很精确地与等高线成一线,也不能完全保护住土壤免受水的侵蚀.例如Dudley Stamp早在1938年在尼日利亚就谈到这些问题.
1. Tillage and Ridge Trenches Creating a small number of small reservoirs in cultivated fields in rainy areas is an effective way to maintain moisture and prevent wind and water erosion as early as the 1930s in the United States The creation of small reservoirs is the first ditching Ridge Ridge, and then in the trench within a certain distance to set up a small slope, and some use manual or mechanical work has proved that manual operation is not resistant to erosion, mainly because they can not Accurately according to contour ridge Ridge, the water is easy to scour the channel and focus on a site, water top and ridge was destroyed.Experiments in the tropics proved that the trench alone for the ridge without the area (tying) Although ridge is very Precisely line with contours does not completely protect the soil from water, as Dudley Stamp discussed in Nigeria as early as 1938.