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美国大多数侵蚀区发生在黄土地区.特别是:1、中部玉米带区.在美国具有最高的侵蚀率,16—26顿/公顷=1.1～1.8顿/亩)这个地区具有降雨强度大为其特征.2、大平原区.主要种小麦.在内部拉斯加和勘萨斯州有部分黄土分布.在这个地区,大的气侯变化与作物产量关系很大.除少数年份有较好收成外,大部分年份产量很低.风蚀是一个严重问题.3、密西西比河流域以陡坡为其特征.肥沃的土壤被侵蚀掉.由于缺乏适宜的保土措施.每年每公顷侵蚀量多达48顿以上(=3.3顿/亩/年)
Most erosion areas in the United States occur in the loess area, in particular: 1. Central Corn Belt area with the highest erosion rate in the United States of 16-26 tons / ha = 1.1 to 1.8 tons / acre) This area has a significant rainfall intensity Characteristics .2, Great Plains area. The main wheat species is partly loess distributed in the interior of Lasagas and Kinshasa. In this area, large changes in climate have a great relation with crop yield, except for a few years with better harvest , Most of the year is very low, and wind erosion is a serious problem.3 The Mississippi River Basin is characterized by steep slopes and fertile soils are eroded away due to the lack of suitable soil conservation measures, with annual erosion of up to 48 tons per hectare Above (= 3.3 tons / mu / year)