摘要 : An acid Alfisol (Typic Paleustalfs) was amended in triplicates at the rate of 5 g kg(-1) soil (12 t/ha) with organic amendment (cow dung (CD), corn cob (CC) and 1:1 CD:CC (CDCC), and 20 kg N ha(-1) as urea, respectively, and plant... 展开 An acid Alfisol (Typic Paleustalfs) was amended in triplicates at the rate of 5 g kg(-1) soil (12 t/ha) with organic amendment (cow dung (CD), corn cob (CC) and 1:1 CD:CC (CDCC), and 20 kg N ha(-1) as urea, respectively, and planted to cowpea in the screenhouse. At flowering stage, plant shoots, roots and nodules were harvested. N-2 fixed was estimated by N-difference method using maize planted and treated the same way as the cowpea as non-fixer. Considering average data for two planting periods, the increases (p < 0.05) obtained with the application of both organic manure with and without N over the control ranged from 125-775% for number of nodules, 96-296% for N-2 fixed, 36-99% for dry matter yield and 160-460% for seed yield. The parameters were higher (p < 0.05) in the organic -inorganic N than in sole manure treatments. The organic amendments increased the pH, organic carbon (OC) and available P contents of the soil at both plantings, with CDCCN and CDCC recording the highest values. Average tissue N and P at the end of the two plantings were similar among all treatments, but average N and P uptakes were higher (p < 0.05) with than without amendments by 26-100% and 238-340%, respectively. Therefore, 5 g kg(-1) cow dung:corn cob (1:1) or 5 g kg(-1) cow dung in sole application or combined with 20 kg N ha(-1) can promote cowpea growth, N-2 fixation and yields with resultant positive effects on soil chemical properties. 收起