摘要
本研究以羊草－沙打旺、羊草－兴安胡枝子、羊草－ 花苜蓿和羊草－ 紫花苜蓿混播草地为对象，比较４种豆科牧草在松嫩平原半干旱地区的生物固氮能力、氮素转移能力以及生物固氮量对草地氮产量的贡献。结果表明，羊草－沙打旺、羊草－紫花苜蓿混播草地氮产量显著高于单播羊草草地，草地粗蛋白含量的增加显著改善了草地质量。沙打旺、兴安胡枝子、花苜蓿和紫花苜蓿生物固氮率为３５％～４０％，大气氮是豆科牧草生长不可缺少的氮素来源。豆科牧草向羊草转移氮素２～１２ｋｇＮ／（ｈｍ２·ａ），占羊草氮产量的５％ ～２４％。豆科植物的固氮能力增加了草地氮素资源，沙打旺、兴安胡枝子、花苜蓿和紫花苜蓿生物固氮量分别占其混播草地总氮产量的２０．３０％，１７．７８％，１１．２９％和３１．７７％。
Biological nitrogen fixation （BNF）, nitrogen transfer and the contribution of nitrogen derived from air to chinen nitrogen yield were investigated sis-Astragalus adsurgens , L. in a semi-arid area of China using four grass-legume mixtures： Leymus chinensis-Lespedeza daurica, L. chinensis-Medicago ruthenica, and L. chinensis-M, sativa cv. Aohan. The nitrogen yield of the L. chinensis-Astragalus adsurgens and of the L, chinensis-M, sativa cv. Aohan were significantly greater than that of L. chinensis mono-culture and they had an improved grassland quality. The BNF of the four legumes was 35%-40%, suggesting that it was an important nitrogen resource for the growth of legumes. The amount of nitrogen transferred from legume to L chinensis was 2-12 kg N/（ha · year）, about 5%-24% of the nitrogen yield of L. chinensis. Legume BNF promoted the nitrogen resources of grassland ecosystems, contributing 20. 30%, 17. 78%, 11. 29% and 31.77% to total nitrogen yield for A. adsurgens, L. daurica, M. ruthenica, and M. sativa cv. Aohan, respectively.
出处
《草业学报》
CSCD
北大核心
2010年第6期276-280,共5页
Acta Prataculturae Sinica
基金
国家重点基础研究发展规划项目(G2000018602)
东北师范大学自然科学青年基金(20050401)资助
关键词
禾-豆混播草地
生物固氮
氮素转移
氮产量
豆科牧草
grass-legume mixture
biological nitrogen fixation
nitrogen transfer
nitrogen yield
legume
