红豆草与紫花苜蓿的培肥效果研究

通过田间小区试验,对比研究了种植豆科牧草红豆草Onobrychis viciaefolia和紫花苜蓿Medicagosativa的产草量和对土壤肥力影响的差异,结果表明:种植当年红豆草产草量大于紫花苜蓿,分别为3 273.0和860.5 kg/hm2,种植次年产草量均有增加,但紫花苜蓿增加明显,分别为3 548.0和1 454.5 kg/hm2,种植第3年红豆草的产草量开始减少,为2 908.0 kg/hm2,紫花苜蓿继续增加至3 535.0 kg/hm2.种植2种豆科牧草均有培肥地力的作用,种植年限越长,有机质和氮素的积累越多,且红豆草培肥作用强于紫花苜蓿.种植2年后.红豆草和紫花苜蓿的耕层有机质含量分别比试验初增加0.74和0.54 g/kg.全氮增加0.466和0.317g/kg,水解氮增加7.9和5.6 mg/kg.2种豆科牧草种植年限越长,土壤中的磷素越低,种植2年后,红豆草和紫花苜蓿的耕层速效磷分别减小4.1和4.6 mg/kg,因此建议每次刈割后结合中耕适当增施磷肥.

Study of Onobrychis viciaefolia and Medicago sativa on Yield and soil fertility

A field experiment was conducted to determine the effects of planting Onobrychis viciaefolia and Medicago sativa on yield and soil fertility.The results of this study showed that the yield of O.viciaefolia was higher than that of M.sativa in the first year,and the yield of O.viciaefolia was almost the same as that of M.sativa in the following year,but the yield of O.viciaefolia was lower than that of M.sativa.The contents of organic matter and nitrogen increased with the years of growing leguminous plant and this indicated that the soil fertility was improved by planting legume.The O.viciaefolia plants had better ability to improvement soil fertility than M.sativa did.The contents of organic matter,the total nitrogen and the hydrolysable nitrogen were higher 0.17 g/kg,0.149 g/kg and 2.3 mg/kg respectively in the three years O.viciaefoli soil.However,the avaliable phosphorus content in soils decreased at the same rate between two leguminous forage pastures.The longer the legume grew,the lower the phosphorus content in soil was,which suggested that application of phosphorus should be used to manage leguminous pasture when cuttings had been undertaken.