施肥是农业生产中补充养分的重要措施，但过量施用化肥的现象越来越严重，导致肥料利用率低，引起土壤肥力下降，破坏农田生态环境。目前，化肥减量和增施有机肥逐渐成为被人们普遍接受和提倡的施肥方式，但仍然存在对有机肥的认识不全面，利用不合理的现象。文章综述了国内外有机肥施用对农田土壤肥力和土壤环境质量的影响效应及作用机理，并对有机肥的合理利用提出了对策。研究表明，有机肥含有丰富的有机质，有机质对土壤肥力水平、土壤重金属有效性和温室气体排放均有至关重要的作用。有机肥能显著改善土壤物理性状，缓解土壤酸化，增加土壤有效养分，维持土壤养分平衡，提高土壤生物和生物化学特性，优化土壤微生物群落的结构组成；然而有机肥（主要来源于畜禽粪便）的长期过量施用会增加土壤重金属含量，加大作物吸收积累重金属的风险，另外，有机肥还可能促进土壤温室气体（CO2，CH4等）的排放，加重温室效应。因此，在农业生产中应加强有机肥的管理，选择安全优质的有机肥（重金属和持久性污染物含量低），建立有机肥施用的配套技术，改革施肥方式，适时适地施肥，有机与无机相结合，尽量降低有机肥施用所带来的环境风险。%Fertilization is an important practice of nutrient supplement in agricultural production. However,excess application of chemical fertilizer is getting more and more serious in recent years,leading to nutrient imbalances and low utilization rate of fertilizer, declining soil fertility and ecological environment degradation of farmland.Nowadays, chemical fertilizer reduction and incorporation of organic fertilizer is widely recommended, especially in organic food production.But people still cannot fully understand and reasonably use organic fertilizer. This paper reviewed the effects and mechanism of organic fertilizer application on soil fertility and soil environmental quality, and proposed development strategies for rational use of organic fertilizers. Large evidence showed that organic fertilizer contains rich organic matter, which has big influence on soil fertility, soil available heavy metal and greenhouse gas emissions. Organic fertilizers can significantly improve soil physical properties, relieve soil acidification, increase soil available nutrients, maintain soil nutrients balance, improve soil biological and biochemical properties, and optimize soil microbial community structure. However, long-term excessive application of organic fertilizers (mainly from livestock and poultry manure) will increase the content of heavy metals in soil and intensify the risk of crop uptake and accumulate heavy metals. Moreover, organic fertilizer may also promote the emission of greenhouse gas (CO2, CH4 etc.) in soil, that aggravating the greenhouse effect. Therefore, in agricultural production, it is necessary to strengthen organic fertilizer management,and choose safety and high quality organic fertilizer (low content of heavy metals and persistent organic pollutants). And the technologies and methods of organic fertilizer application is also important, combined organic and inorganic fertilizer application according to the climate and soil characteristics were recommended so as to minimize the environmental risks.
展开▼
