松嫩地区禾-豆混播草地生产力研究

The productivity of grass-legume mixture in Songnen area of China

本实验比较研究了羊草分别与5种豆科牧草,沙打旺、兴安胡枝子、花苜蓿、紫花苜蓿、山野豌豆的混播草地干物质产量和氮产量。实验采用置换系列设计,建立总密度为900株/m2、禾/豆比为1:0、1:2、2:1和0:1的混播小区。研究结果表明,羊草-沙打旺、羊草-紫花苜蓿混播地干物质产量在建植当年高于羊草单播地;5种物种组合的所有混播地干物质产量在建植第二年略高于羊草单播地,但增产程度未达到显著水平。羊草-沙打旺、羊草-花苜蓿和羊草-紫花苜蓿混播地氮产量显著高于羊草单播地。羊草与胡枝子、山野豌豆的混播地氮产量与羊草单播地相似。沙打旺和紫花苜蓿的干物质产量和氮产量在混播草地总产量中占绝对优势,与之混生的羊草产量受到强烈抑制。花苜蓿干物质产量和氮产量在高比例羊草混播地中受到一定程度的抑制,在低比例羊草混播地中未受到干扰。兴安胡枝子和山野豌豆干物质产量和氮产量在混播草地总产量中所占比例小,其种群生长受到羊草强烈的抑制作用。

The dry matter yield and nitrogen yield of five different two species grass-legume mixtures,which combined by Leymus chinensis with Astragalus adsurgens、Lespedeza daurica、Medicago ruthenica、Medicago sativa cv.Aohan、Vicia amoena respectively,were investigated and compared.The experimental plots were established by replacement series with 1：0,1：2,2：1 and 0：1 number ratio of grass/legume at total density of 900 plant/m2.Results indicated that the DM yield of mixtures with A.adsurgens and M.sativa were higher than L chinensis monoculture in the first year,however the over-yields of all the mixtures were not significant when compared with grass monocuhore at the second year.The nitrogen yield of mixtures with A.adsurgens,M.ruthenica and M.sativa were significantly higher than that of L chinensis monoculture while the other two mixtures had the similar yield with L chinensis monoculture.In the mixtures,both the DM and nitrogen yield of A.adsurgens and M.sativa were absolutely higher than L.chinensis,which was suppressed intensively by legumes. Decreased DM and nitrogen yield of M.ruthen/ca were occurred when growing with higher proportion of L.chinensis,while no change when with lower proportion of L.chinensis,the DM and nitrogen yield of L.daurica and V.amoena,which were suppressed intensively by grass,were absolutely lower than L.chinensis in mixtures.