摘要
通过现场土壤样品采集和室内分析测试,研究了小叶章湿地开垦后汞和有机质的动态变化。结果表明,湿地开垦后耕作层土壤汞和有机质的含量在开垦初期降低迅速,随后缓慢降低,开垦12a到22a间略有上升;犁底层对环境变化的响应较慢,其含量在初期略有上升,随后缓慢降低,在开垦12a后基本上达到平衡。土壤汞和有机质含量具有明显的垂直分异性,随着开垦时间的延长垂直差异减小。土壤汞和有机质含量极显著相关,随着有机质的降低,有机质结合态汞含量也不断降低,并向其他形态转移。pH在开垦初期的降低将利于汞的迁移,而后期的升高则利于土壤汞的保持。
s: Contents of Hg and organic matter at plough horizon decreased quickly in the initial stages of reclamation, reduced slowly between the 8～ 12th year and increased very slowly between the 13～ 22nd year after reclamation. The contents of Hg and organic matter at plough pan layer increased a little in the initial stages of reclamation, then decreased slowly and became stable during the 12th year after reclamation. Hg in soil could moved to deeper layer after reclamation. There was clear vertical variability for Hg and organic matter, and the vertical variability decreased following the increase of reclamation years. There were close relations between Hg and organic matter. Hg bound to organic matter decreased with the decomposition of organic matter, it may transform into other speciation. The decrease of pH facilitated to the transportation of the metal in the soil, but the increase of pH was just reversed.
出处
《农业环境科学学报》
CAS
CSCD
北大核心
2003年第6期647-650,共4页
Journal of Agro-Environment Science
基金
国家自然科学基金(40071072)
中国科学院重要方向资助项目(KZCX2-302)
