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保留带（ 保留现有灌丛的带状区域）与造林带（ 砍掉现有灌丛用于栽植林木的带状区域） 沿等高线交替配置的生态技术在四川西部逐渐被推广应用，本文定量分析了该技术中保留带与造林带的水土和养分再分配效应．结果表明：①坡度和雨量级是影响保留带与造林带水土流失的重要因子，其越大则水土流失量越大．②保留带净存储水６１ ４６４ ～１２５ １７９ｔｋｍ －２ａ－１ ，拦截土壤２ １３６ ～２ ８１７ｔｋｍ －２ａ－１ ．③保留带表土层的养分比造林带的提高了１４．６８％ ～７４．８９％ ，造林带表土层的养分比对照提高了３ ．３１％ ～１１４．１６％ ．④保留带和造林带内从上至下的表土层养分有逐渐富积的趋势，且保留带与造林带相邻处的养分变化速率最大．⑤保留带通过地表径流的养分流动净积累了５７５ ．５９ ～１ ６９０ ．６６ ｋｇ ｋｍ －２ａ－１有效Ｎ；而对Ｐ、Ｋ 而言，保留带是否能通过地表径流来净积累养分则主要取决于坡度，坡度越大，越有利于保留带通过地表径流来净积累有效Ｐ、Ｋ．
The ecological technologies that alternate the belt along the contours of the belt (retaining the belt-like area of the existing shrub) and the afforestation belt (the strip-like area cutting the existing shrubs for the planting of the forest) are gradually being popularized and applied in the western part of Sichuan The water, soil and nutrient redistribution effects of the reservation zone and the afforestation zone were quantitatively analyzed. The results show that: (1) The slope and rainfall level are important factors that affect the soil erosion in the reserve belt and the afforestation zone. The larger the soil erosion amount, the larger the soil erosion amount. ② Reserves with net storage of 61 464 ~ 125 179tkm -2a-1, interception of soil 2 136 ~ 2817tkm -2a-1. (3) The nutrient content of topsoil retained in the topsoil increased by 14.68% -74.89% compared with that in the afforestation zone. 31% ~ 114.16%. (4) Nutrients in the topsoil from top to bottom in the reservation zone and afforestation zone tend to be gradually enriched, and the rate of nutrient changes adjacent to the reservation zone and afforestation zone is the highest. (5) The net nutrient accumulation of the reservation zone through the surface runoff accumulated 575. 59 ~ 1 690. 66 kg km -2a-1 effective N; for P and K, the net accumulation of nutrients through surface runoff depends on the slope, the greater the slope, the more conducive to the net accumulation of the reserve zone by surface runoff Effective P, K.