【摘要】 研究了麦秆不同方式还田、施用无机氮肥及不同移栽时间对水稻田土壤溶液中溶解性有机碳(DOC)、溶解性有机氮(DON)浓度的影响。结果表明,淹水后土壤溶液中DOC浓度在淹水初期明显增加,而后逐渐下降。添加麦秆这一有机物料,在水稻生长期前2个月内显著提高了DOC,对DON在一段时间内也表现出促进作用,其后差异不显著。施用无机氮肥降低了土壤溶液中DOC、DON浓度。DON的浓度与施肥量呈负相关。水稻推迟移栽,土壤溶液中溶解性有机质(DOM)均显著降低。更多还原

【Abstract】 Dissolved organic carbon(DOC) and dissolved organic nitrogen(DON) are the main components of soil solution and involve in many soil processes.An experiment was carried out to study effect of wheat straw incorporation,nitrogen fertilization and transplant date management on dissolved organic carbon(DOC) and dissolved organic nitrogen(DON) in soil solution in paddy field.Soil solution samples were obtained by centrifuging fresh soil samples.Results show that the concentration of DOC in soil solution was significantly increased at the initial stage of flooding and then decreased gradually regardless of straw incorporation.Wheat straw incorporation significantly increased DOC in the first two months of flooding,and DON,too,in the initial period.Application of inorganic nitrogen led to a decrease in concentrations of DOC and DON.The concentration of DON decreased with fertilizer nitrogen application rate increasing.When the soil was flooded in the same time,delayed transplantation of rice seedlings for three weeks significantly decreased DOM.更多还原