种植苜蓿对台安县沙化区土壤改良效应的研究

在台安县西北部沙化土地上种植紫苜蓿，产生明显改良土壤的效果。通过对苜蓿地和对照区地表层土壤层取样分析，从定量的角度研究了种植紫苜蓿对表层土壤理化性质的影响。结果表明：与对照区相比，苜蓿地在未施用肥料的情况下，土壤有机质、全氮、全磷、全钾、速效氮、速效磷、速效钾的含量均比每年都施肥的对照区高，且差异显著。种植苜蓿可以降低土壤容重，增加土壤孔隙度。

Study of the Effect of the Soil Improvement of the Aeolian Sandy Soil by Planting Alfalfa in Tai'an County

An obvious Effect of the Soil Improvement was achieved after the planting of alfalfa i＇n the northwest aeolian sandy soil area in Tai＇ an County. Through the quantitative analysis of the sample topsoil taken from the alfalfa - planted area and from the contrast area, the author has studied the influence brought about by planting alfalfa upon the physiochemical property of the topsoil. This study shows that, compared with the contrast area, the content of the soil organic matter, total nitrogen, total phos- phorus, total potassium, quick - acting nitfide, quick - phosphorus and quick - acting potassium in the non - fertilized alfalfa - planted area is higher than that in the annually fertilized area and their difference is very remarkable. The study also indicates that the planting of alfalfa may reduce the volume weight of soil, and increase the soil porosity.