施肥与土壤健康质量论施肥对环境的影响（3）

就施肥与土壤健康质量而言,有机肥的问题比无机肥的更严重。无机的N肥、K肥是化学晶体,比较洁净,导致污染的可能性不大。国产P矿为原料的P肥和钙镁磷肥的Cd含量也较低,但进口的磷矿粉以进口P矿为原料的P肥的Cd含量较高,是无机肥料对人畜健康的主要危险。有机肥有病原微生物,有机毒物及重金属污染的问题。从生态安全和充分利用自然资源看,有机堆肥、污泥堆肥是必须开发利用的。因其使用量特别大,所含污染物的危险性也就较大。制定相应的法规和有机肥产品的质量标准进行监督和控制是紧要的任务。建议其产品主要应用在林木、草坪、花草及木本经济作物上,蔬菜和一年生的粮食作物上应慎用。

EFFECT OF FERTILIZATION ON SOIL HEALTH QUALITY--Effect of Fertilization On Environment Quality (3)

As far as effect of fertilization on soil health quality is concerned, organic compost poses more problems than mineral fertilizers. Inorganic N and K fertilizers are crystal compounds with quite high purity and less contamination of heavy metals and other materials. Commercial phosphate fertilizers, and Ca-Mgphosphate made from domestic phosphate rocks are relatively low in Cd content, while those imported phosphate rock and super-phosphate, and ammonium phosphate fertilizers (whether domestically produced or imported) are generally high in Cd and other heavy metal content. Long term use of P fertilizers will result in contamination of Cd and other trace elements of the soil and crop products. Organic compost fertilizers are complicated in composition, containing pathogen microbes, organic toxic pollutants and heavy metals etc.. From the viewpoint of recycling of organic resources and ecosystem safety, organic compost must be exploited and used. Owing to its huge quantity in use, the impact to soil health quality should be monitored and well managed. It is, therefore, essential to establish corresponding regulations and quality criteria for compost production and application. Organic compost should mainly be used for production of forests, lawns, flowers, and woody economic crops. Cautions should be taken for use in vegetable and annual food crops.