杉林土壤溶解有机碳吸附及影响因素分析

用模拟实验的方法借助原始物质吸附等温线对杉林土壤溶解有机碳(DOC)的吸附及其影响因素进行了研究。结果表明,下层土壤比上层土壤有更强的DOC吸附能力,土壤DOC吸附的量与平衡前DOC的浓度显著相关,溶液中的 pH,磷、铁和铝的含量影响土壤对 DOC的吸附。pH为 5.0 时土壤对 DOC的吸附最强,pH为7.0时最弱;磷能阻止DOC的吸附,铁、铝则增加土壤对DOC的吸附,铁的含量对DOC吸附的影响明显大于铝。DOC对土壤铁、铝的溶出量有明显影响,铝的溶出量和溶出率要大于铁。DOC对下层土壤铁铝溶出量的影响要大于上层土壤。

The Dissolved Organic Carbon(DOC) Adsorption and Its Influence Factor on the Soil of Chinese Fir Plantation

Dissolved organic carbon(DOC) adsorption and its influence factor on the soil of Chinese fir plantation were studied with IM isotherm in laboratory experiments. The quantities of DOC adsorption in the lower soil are greater than that of the upper soil.There were remarkable linear relations between the quantity of DOC adsorption on soils and the initial DOC concentration in the solution before balanced.pH,concentrations of phosphorus,iron,and aluminum in solution affect the absorption of DOC obviously.There was highest DOC absorption at pH 5.0,and lowest at pH 7.0.Phosphorus in solution prevent the absorption of DOC,whereas Fe~(3 ) and Al~(3 ) increase the DOC adsorption.The concentration of Fe~(3 ) in solution has greater influence on DOC absorption than that of aluminum.DOC affects the Fe~(3 ),Al~(3 ) dissolution greatly.The quantity and proportion of dissolved Al~(3 ) are greater than that of Fe~(3 ).The effects of DOC on Fe~(3 ),Al~(3 ) dissolution in lower soil are greater than that of upper soil.