Evaluation of N_2-Fixing Capacities of Herbaceous andShrub Legumes Under Field Condition

查看全文 作　　者：XING GUANGXI;SHI SHULIAN;CAO YACHENG;DU LIJUAN;SUN GUOQING and ZHOU KEYU(Institute of Soil Science, the Chinese Academy of Sciences, Nanjing 210008 (China)) 出　　处：《Pedosphere》索引1998年第8卷第1期,共4页 摘　　要：Natural 15N abundance method was used in this study to investigate the N2-fixing capacities of several herbaceous and shrub legumes by a field experiment. For herbaceous legumes, the results were in consistent with those obtained by a pot experiment. Crotalaria mucronata Desv. had a higher N2-fixing capacity than Vigna sinensis (L.) Savi. For shrub legumes, N2-fixing capacity under field condition was slightly different from that in pot experiment. These results demonstrated that the natural 15N abundance method was applicable to evaluating N2-fixing capacities of herbaceous and shrub legumes, and that pot experiment was suitable for evaluating the N2-fixing capacities of not only herbaceous legumes but also shrub legumes.Leguminous N2-fixing plants differed in response to phosphorus fertilization. Phosphorus fertilizer application greatly increased the percentage of nitrogen derived from air (% N dfa) and total amount of N2 fixed by Lespedeza formosa (Vog.) Koehne (Jiangxi). Phosphorus fertilizer showed no significant effect on the N2-fixing percentage of Cajanus cajan (L.) Millsp. but increased its total biomass, thus increasing the total amount of N2 fixed. 关 键 词：草本 自然氮 富集机理 灌木 固氮作用 磷肥 豆科植物 豇豆 胡枝子