旱地基于豆类绿肥不同轮作方式的经济效益分析

【目的】黄土高原旱地土壤贫瘠,传统的夏休闲期雨热资源丰富但利用率不高,评价不同轮作方式的经济效益,为选择一种合理的种植模式、 保证农民获得可靠的收入提供依据。【方法】本研究通过4年定位试验,以夏休闲-冬小麦一年一熟制为对照,测定并分析了豆类绿肥-冬小麦和豆类绿肥-春玉米-冬小麦两种轮作方式及其不同豆类绿肥处理方式条件下的经济效益。【结果】豆类绿肥-冬小麦轮作经济效益最低,而且纯收入的变异系数高达67.69%,与夏休闲-冬小麦轮作方式相比没有优势; 该轮作绿肥不同翻压时间对作物产量、 总收入等指标存在年际差异。豆类绿肥-春玉米-冬小麦轮作,整体收入最高,而且纯收入变异系数最低,为15.42%,其中茎秆覆盖和茎秆翻压处理的作物产量、 总收入、 纯收入等均高于移出处理。【结论】从农民收入的角度来看,豆类绿肥-春玉米-冬小麦轮作很好的平衡了成本与收益的关系,是该地区较为合理的种植制度; 将绿肥籽粒收获后,茎秆覆盖式翻压,可有效提高小麦、玉米的产量,是应推广的技术措施。

Profit analysis of different rotations based on leguminous green manure in dryland area

Objectives] In dryland area of Loess Plateau, soil is barren, and the heat and precipitation resources can hardly be fully utilized during summer fallow period. Therefore, a better cropping system is needed to secure the farmer’s income depending on the results of a profit analysis of different rotations. [Methods] A 4-year field trial was conducted to assess economic benefits of two rotations and corresponding green manure treatments. Leguminous green manure-winter wheat (LG -WW) and leguminous green manure-spring maize-winter wheat (LG-SM-WW) were compared with summer fallow -winter wheat (SF -WW) as control, a widely applied rotation in local area. [Results] LG - WW has the lowest economic benefits, and the coefficient of variation ( CV) of net benefits for LG -WW is 67. 69 % , which indicates the rotation thus couldn’t replace the traditional SF -WW. The differences of wheat yields and gross revenue among the green manure treatments for this rotation vary from year to year. LG -SM -WW has the highest gross revenue and the lowest CV (15. 42 % ) of net benefits among the three rotation systems, which implies that farmers could achieve a high and stable income by applying this rotation. Crops yields and economic benefits under the straw mulch and incorporation treatments for this rotation are higher than those of move-away treatment in LG-SM -WW rotation. [Conclusions]Legume -summer maize -whinter wheat rotation is the most profitable cropping system in the dryland of Loess Plateau. After harvesting the pods of legumes, the straw is recommended to mulching or incorporated for higher yield of maize and wheat.