摘要
采用模拟培养的方法,通过测定土壤表层培养液的电导率、pH、不同形态氮、全磷、全钾等指标,研究了油菜秸秆用量对淹水培养土壤表层溶液理化性质的影响。结果表明,各处理土壤表层溶液电导率在培养初期呈上升趋势,第8d达到最大,随后呈下降的趋势。pH值在培养的前3d呈缓慢下降的趋势;从第4d开始迅速升高;16d后达到相对稳定的状态,随后变化不大。在培养初期全氮浓度迅速增加,第8d达到最大,随后迅速下降;到第44d,下降趋势开始减缓,不同处理之间相差不大。铵态氮的变化趋势与全氮的变化趋势一致。各处理间硝态氮含量较低,差别不显著。施加秸秆能够增加水溶液中有机氮浓度。全磷在培养初期变化较小,第12d开始迅速升高,第20d达到最高,随后呈下降趋势。施加秸秆后对田面水溶液全钾浓度的影响主要发生在培养后第1d,整个培养期内变幅不大。施加秸秆能够增加培养液中养分含量,与秸秆用量成正比。从养分流失角度考虑,控制氮素、磷素和钾素田面流失主要时期为秸秆还田后30d内。
The objective of this research was to determine the effect of rape straw and its returned rates on soil surface solution properties through a simulation experiment. Four rape straw rates was designed as 0,100,200 and 300 g/pot and electrical conductivity （EC）,pH,total nitrogen （TN）,ammonium nitrogen,nitrate nitrogen,organic nitrogen,total phosphorus （TP）,total potassium （TK） were measured during the 116 d experiment. The result showed EC was increased obviously at beginning and the peak value appeared at the 8th day. Subsequently,EC was declined obviously. There was positive correlation between EC and amount of straw. The pH had slow decrease trend at the 3 beginning days,and then increased rapidly until 16 days and then kept a relatively stable state. The result showed each treatment had a high TN concentration at the beginning of the experiment,and TN was declined rapidly from 20th day to 76th day,but there was no difference for TN among different treatments. NH4^＋-N had the similar trend as TN. NO3^--N was almost existed. Organic nitrogen was higher than CK. TP was increased obviously at beginning and the peak value appeared at the 20th day,and then was declined obviously. TK was varied obviously after 1st day,and kept a steady level in the whole days. It was discovered that the nutrients in surface solution was proportional to the rape straw amount. In terms of the nutrient loss,the period within 30 days after the straw application was a critical time to control N,P,K loss and leaching from flooded paddy field.
出处
《水土保持学报》
CSCD
北大核心
2010年第1期197-201,共5页
Journal of Soil and Water Conservation
基金
国家"十一五"科技支撑计划重点项目(2008BADA4B08)
国家土壤有机质提升项目
关键词
油菜秸秆
模拟培养
土壤表层溶液
理化性质
养分流失
rape straw
simulation experiment
soil surface solution
physicochemical properties
nutrients loss
