Abstract: In order to analyze the economic benefits of two grain-grass rotation modes (alfalfa+3-year wheat+alfalfa and wheat+4-year alfalfa) in the desert area of Northern Xinjiang Plain,a field survey was carried out for five consecutive years in the Hutubi core experimental area,and the grain-grass yield,input cost,profit and output-input ratio under the two modes were compared. The results showed that annual total profit under wheat-alfalfa-alfalfa-alfalfa planting pattern was 18.71% higher than that under alfalfa-wheat-wheat-wheat-alfalfa planting pattern. Grain yield increased by 25% in the first two years of continuous alfalfa rotation compared with continuous wheat rotation. After wheat rotated alfalfa,the hay yield of alfalfa decreased year by year,annual average grain-grass profit after 3-4 years alfalfa rotation was 9 050 CNY·hm^-2,which was 3.26 times higher than only wheat. Introducing low cost alfalfa into grain farming system could increase crop yield,increase crop rotation profit and solve the problem of protein feed shortage.

Key words: Grain-grass rotation, Desert area of northern Xinjiang plain, Economic benefit

摘要： 为分析北疆平原荒漠区苜蓿（Medicago sativa）（1年）+小麦（Triticum aestivum）（3年）+苜蓿（1年）和小麦（1年）+苜蓿（4年）2种粮草轮作模式的经济效益，本研究在呼图壁核心试验区开展连续5年的实地调查，比较了两种模式下粮草产量、投入成本、利润和产投比。结果表明：小麦（1年）+苜蓿（4年）种植模式下年均总利润较苜蓿（1年）+小麦（3年）+苜蓿（1年）模式提高18.71%；老苜蓿地倒茬种植小麦的前两年籽粒产量较小麦连作增产25%；小麦倒茬轮作苜蓿后，苜蓿的干草产量呈逐年下降趋势，种植3~4年苜蓿的年均粮草利润为9 050 元·hm^-2，是小麦的3.26倍。综上所述，在粮食耕作系统中引入低成本苜蓿，可提高作物产量，增加轮作的利润，解决蛋白质饲料短缺的问题。

关键词: 粮草轮作, 北疆平原荒漠区, 经济效益