稻田土壤肥力评价方法及指标研究进展

水稻土作为典型的水耕人为土,其土壤肥力是水稻优质高产的重要基础,肥力评价是稻田培肥和管理的重要内容之一。然而,稻田肥力评价指标和方法的选择存在较大不确定性。通过分析不同土壤肥力评价方法特点,土壤肥力指标的影响因素和变化特征,对我国水稻土肥力评价的现状进行了总结。在选择评价方法时应最大程度地减少人为的主观性,同时,如何将作物产量纳入土壤肥力综合评价值得进一步探讨。在对稻田土壤肥力进行综合评价时,土壤容重、总孔隙度、土壤团聚体和黏粒含量可作为土壤物理肥力指标的主要因子;土壤化学肥力指标随着施肥、耕作模式和稻作区域的差异应各有侧重;众多的土壤生物学指标中,微生物量碳氮、酶活性和微生物群落结构等需重点关注。下一步应制定一套针对不同稻作区典型施肥和耕作模式下比较完整和有代表性的评价指标体系,以及客观又简单实用的评价方法,为以水稻高产优质为目标的土壤培肥技术提供参考。

A review on the evaluation methods and indexes of soil fertility in paddy fields

Paddy soil as a typical stagnic anthrosols,its soil fertility plays an important role on the high quality and productivity of rice.The fertility evaluation is very important to the fertility improvement and management of paddy soil.However,the selections of the assessment index and method for paddy soils still remain unclear.Thus,in this study,the characteristics of fertility evaluation methods and the effects of different factors on evaluation index were analyzed.Meanwhile,the research progress on the fertility evaluation of paddy soil across China was discussed.The evaluation method should minimize the human subjectivity.Meanwhile,how to integrate crop yield into soil fertility comprehensive evaluation system is worthy to be further discussed.In order to comprehensively evaluate soil fertility of paddy soil,the soil bulk density,total porosity,soil aggregate and clay content could be classified as the main factors of soil physical fertility index.The evaluation indexes of chemical fertility of paddy soils were different with the various fertilization strategies,tillages,and rice planting regions.Among the most important soil biological indicators,the microbial biomass carbon and nitrogen,enzyme activity and microbial community structure were identified as the main indicators.The relatively complete,representative evaluation index system and objective,simple,practical evaluation method should be established for typical fertilization and tillage models in different rice cropping areas in next step to provide reference for soil fertilization technology that aim at high yield and good quality of rice.