摘要
温室蔬菜生产中普遍存在着土壤硝态氮积累及地下水硝酸盐污染问题,合理调控氮素是减少氮素淋洗的重要措施之一。文章在京郊温室栽培条件下,以农户的习惯施肥措施为对照,在菜田夏季休闲期间施用秸秆-氰胺化钙并结合作物后期的氮素追施调控技术对秋冬茬黄瓜的生长及土壤硝态氮残留进行研究。结果表明:与当地农户的习惯施肥措施相比,采用秸秆-氰胺化钙综合调控技术显著提高黄瓜的产量,增产率达到20%;显著减少氮素追施数量,并具有最低的根层土壤无机氮(Nmin)含量;收获时该处理的土壤剖面(30～180cm)中硝态氮的积累量比农户习惯施肥降低388kg·hm-2,其中最明显的差异出现在30～90cm土层。表明采用秸秆-氰胺化钙综合调控措施通过土壤氮素形态的调控,明显减轻黄瓜生长季节期间的硝态氮淋洗的风险。
Excessive nitrate accumulation in protected vegetable fidd is a popular problem, which may lead to the high risk of groundwater pollution. Reasonable nitrogen management is an important practice to decrease the leaching loss of nitrate. A field experiment was conducted in Shunyi, Beijing suburb, in order to investigate the effects of applying for Calcium Cyanamide mixed with wheat straw based on balanced N topdressing （CC＋WS＋optimized N） on cucumber growth and soil nitrate accumulation in autumn-winter season. The results showed that compared to farmer conventional fertilization practice, no topdressed N was needed in CC＋WS and optimized N treatment, however at harvest cucumber yield significantly increased by 20% in the treatment, Meanwhile soil Nmin content in the root zone of CC＋WS and optimized N treatment was lowest among the three treatments during cucumber growth period. Soil Nmin accumulation below the root zone （30-180 cm） decreased by 388 kg·hm^-2 compared with farmer conventional fertilization practice. Significant difference of Nmin accumulation was investigated in 30-90cm soil profile between CC＋WS and optimized N treatment and farmer conventional fertilization. It means that using CC＋WS and optimized N management can significantly decrease the risk of nitrate accumulation and leaching to groundwater in the intensive vegetable field.
出处
《生态环境》
CSCD
北大核心
2006年第3期633-636,共4页
Ecology and Environmnet
基金
国家十五攻关项目(2004BA521B04)
农业部948项目(2003-Z53)
