几种复合肥施用对蔬菜保护地土壤环境质量的影响

Effects of Compound Fertilizers Utilized on Soil Environmental Quality in Protected Vegetable Field

采用大棚小区试验方法,研究了保护地条件下,不同复合肥品种及施肥量对蔬菜地土壤不同剖面硝酸盐含量、pH值及电导率在不同生长季节内的动态变化情况的影响。结果表明,几种肥料的施用,不同程度地降低了表层土壤pH值,同时增加了各剖面土壤电导率和硝酸盐含量。施肥量越大,土壤pH值、电导率和硝酸盐含量的变化越明显。随时间的推移,土壤环境质量呈恶化趋势。大量频繁施用化肥,是导致土壤酸化、土壤盐分累积和硝酸盐淋洗的主要原因。确定合理的施肥量,平衡氮、磷、钾养分比例,以及采取正确的施肥和灌溉方式,将有效缓解土壤酸化和盐分累积,减少硝酸盐的淋洗,从而改善土壤环境质量。

Effects of several kinds of compound fertilizers on soil environmental qualities were studied in protected vegetable fields. The results showed that all fertilization treatments decreased pH value in 0—30 cm soil layer, while increased EC and nitrate-nitrogen concentration in 0—90 cm soil profiles. The problems were more serious when more fertilizers were used. The superfluous and frequent fertilization resulted in soil acidification, salinification, accumulation and nitrate loss by leaching. It is suggested that balanced rates of N, P and K application, fertilization with reasonable amount and manners be taken to abate the potential of nitrate leaching loss, and to improve soil environmental quality.