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本文研究了实现保土柔量(conservation compliance)在爱达荷州Tom Beall(简称TB)流域的侵蚀、泥沙和经济影响,确立了可使土地、劳力和经营的年净收益最大,且流域中所有地块的侵蚀率均限定在保土柔量所决定的标准——11.2和16.8(t/ha.a)(即T和1.5T)以内的资源管理系统.其中包括三种耕作制度,三种土地管理措施及九种作物的轮作.用通用土壤流失方程(USLE)估计年侵蚀率,采用农业非点源污染模型(AGNPS)计算了四次暴雨事件中流域出口的泥沙输移变化.利用临近气象站的日降雨资料,将各单场暴雨的泥沙输移累加为全年的泥沙输移量.优化资源管理系统由分坡级种植、小麦和豌豆或小麦——豌豆——小麦——豌豆——草田轮作的少耕耕作制组成.它与传统的等高耕作制(记为CTCF)相比,流域总侵蚀量减少了67%～71%;与少耕等高耕作制(RTCF)相比,减少了25%～39%.每年泥沙输移和侵蚀造成的损失,与CTCF比减少了70%,与RTCF比,减少了23%.CTCF的泥沙损失是RTCF的2.5倍.总净收益相对于CTCF增加了11%～16%,相对于RTCF减少了1%～4%.1.5T标准比T标准有更高的社会效益,前者较后者也更易于实现.
This paper examines the erosion, sediment and economic impacts of implementing conservation compliance in Tom Beall (Idaho) watersheds and establishes that annual net benefits of land, labor and operations can be maximized and that river basins Erosion rates for all plots in the area are limited to the resource management system that is defined by the tactility criteria - 11.2 and 16.8 (t / ha.a) (ie T and 1.5T), including three tillage systems, Three kinds of land management measures and rotation of nine crops.Using the generalized soil loss equation (USLE) to estimate the annual erosion rate, the agricultural non-point source pollution model (AGNPS) was used to calculate the sediment transport change in the basin export during the four heavy rainfall events Using the daily rainfall data of the adjacent weather stations, the sediment transport of each single heavy rainstorm is accumulated as annual sediment transport.The optimized resource management system consists of sub-grade planting, wheat and pea or wheat-pea- - wheat - pea - grass field rotation tillage system composed of less than its traditional high-altitude farming system (referred to as CTCF), the total basin erosion decreased by 67% to 71%; with less tillage and other tillage (RTCF) compared to a reduction of 25% to 39% annual sediment transport and erosion made , A decrease of 70% from the CTCF and a 23% decrease from the RTCF. The CTCF sediment loss is 2.5 times that of the RTCF and its total net income is 11% to 16% relative to the CTCF, relative to the reduction in RTCF 1% ~ 4% .1.5T standard T standard has higher social benefits, the former is more easily than the latter to achieve.