不同土壤改良措施对低产黄泥田土壤性质及水稻产量的影响

在荆门市双季稻区研究了不同的土壤改良措施对土壤腐殖质组成及结合形态、土壤理化性质、双季稻产量的影响。结果表明：不同土壤改良措施均提高了土壤水溶性物质、胡敏酸、胡敏素含量、可提取腐殖物质总量，其中泥炭土、菇渣及生物有机肥处理增幅较大；不同土壤改良措施增加了土壤松结合态腐殖质、稳结合态腐殖质、紧结合态腐殖质含量及结合态腐殖质总含量，其中生物有机肥处理达到显著水平。各土壤改良措施均不同程度地增加了早、晚稻产量，平均比单施化肥处理的早稻增产6.6％、晚稻增产9.5％；同时提高了土壤有机质、全氮、碱解氮、有效磷、速效钾含量与阳离子交换量，降低了土壤容重。各改良措施中，生物有机肥处理的增产幅度较大，早、晚稻分别增产10.13％和17.50％，且对土壤理化性质的改良效果优于其它处理。

Effects of different soil melioration practices on soil properties and rice yields in low-yielding yellow clayey land

The effects of soil melioration practices on composition and combining form of soil humus, soil basic physical-chemical properties, rice yields and yields component were studied in low-yielding yellow clayey land in double cropping rice system of Jingmen, Hubei Province. The results showed as follow: The contents of soil water soluble substance, humic acid, humin and extracted humic substances were higher in soil melioration treatments than that in the single application of chemical fertilizer treat-ment, especially, in peat soil, mushroom residue and biological-organic manure treatments. The contents of loosely, firmly, tightly combined humus and total combined humus were higher in soil melioration treatments than that in the single application of chemical fertilizer treatment. In contrast to single application of chemical fertilizer treatment, biological-organic manure treatment significantly (p<0. 05) increased the content of loosely combined humus and total combined humus. The early and late rice grain yields were increased owing to soil melioration by 6. 6%, 9. 5%, respectively. Moreover, soil melioration practice in-creased the content of soil organic matter, total N, alkali-hydrolysable N, available P, available K, and cation exchange capac-ity, nevertheless, soil bulk density were decreased. Effect of biological-organic manure on soil improvement was evident than other soil melioration treatments, and early and late rice grain yields were increased by 10. 13%, 17. 50%, respectively.