摘要
在小麦生长季节对太湖地区典型土壤乌栅土中NO3--N、NH4+-N和速效磷的动态变化进行研究。结果表明:土壤中NO3--N含量在不同生长阶段差异较大,小麦播种后NO3--N含量最低,然后开始逐渐积累,在小麦灌浆成熟阶段含量最高;NH4+-N含量与NO3--N表现出类似的趋势;速效磷含量在不同阶段差异很小。在土壤剖面中NO3--N从土壤表层到底层迅速下降,表层NO3--N的含量是底层NO3--N含量的数倍,NH4+-N含量从上层到下层逐渐递减;速效磷从表层到底层呈逐渐下降的趋势,各个层次土壤中的速效磷含量变化很小;由于降雨比历史同期偏少,土质黏重,NO3--N的淋失减少,NH4+-N和土壤溶液中速效磷容易被吸附固定,所以土壤养分运移对研究区地下水影响较小。小麦生长季节,由于土体裂隙较多,导致土壤中养分含量与饱和导水率关系不明确;养分含量与黏粒呈显著的线性负相关;与有机质呈显著的线性正相关在一定程度上用有机质含量表征土壤中有效养分对生态环境的影响是可行的。
Nitrite, ammonium, and available phosphorus contents in the typical Wushan soil from Tai Lake region during wheat growth were studied. The results were as follows. The nitrite contents varied greatly at different wheat growth stages, being lowest right after wheat planting and then gradually accumulating and highest at wheat filling and ripening stages, separately. Ammonium content had the same trend with nitrite. Available phosphorous contents varied little at different wheat growth stages. Nitrite contents decreased rapidly from top soil to subsoil along soil profiles, and nitrite contents at surface layer were several times higher than bottom soil layer. Ammonium content was decreased slowly with soil depth, and available phosphorous contents had the same trend but changed less at different layers. As the rainfall was less than those of the same period in the history, the heavy clay soil reduced the nitrate leaching. The ammonium was absorbed by soil particles with negative charge. The available phosphorous in soil solution was likely to be absorbed and fixed by soil particle, therefore the leaching soil nutrients had less impact on underground water. During the wheat growth, the relationship between Ks and nutrients was fuzzy because of fractures in the soil. Nutrients had significant positive correlation with clay content, and the nutrients had significant negative correlation with organic matter. To some extent, soil organic matter content could represent the influence of soil nutrients on ecological environment.
出处
《土壤通报》
CAS
CSCD
北大核心
2013年第2期380-384,共5页
Chinese Journal of Soil Science
基金
公益性行业(农业)科研专项经费项目(200903003)资助
关键词
太湖地区
乌栅土
氮
磷
Tai Lake region
Wushan soil
Nitrogen
Phosphorus
