设施土壤有机碳组成特征及光学性质研究

Organic matter characteristics and optical properties in Greenhouse soil

对沈阳市东陵设施栽培土壤有机碳组成特征及其光学性质进行研究,以棚外的露地土壤为对照,结果表明:随着有机碳的增加,设施土壤非腐殖物质碳、腐殖质碳数量均明显增加,分别是露地土壤的1.61～2.45倍、1.08～2.27倍。设施土壤非腐殖质物质碳占总有机碳的比例较露地土壤大,其水浮物质碳所占百分比是露地土壤的1.19～1.65倍,而水溶性有机碳,设施土壤和露地土壤所占百分比均在2%左右。设施土壤胡敏酸和胡敏素所占总有机碳比例表现出随着有机碳含量的增加而升高的趋势,但胡敏酸碳增加的比例小于胡敏素碳。设施土壤可提取腐殖物质、胡敏酸的光密度曲线斜率、E4/E6值、ΔlogK值都小于露地土壤,表明设施土壤可提取腐殖物质、胡敏酸的分子复杂程度、芳香缩合度低于露地土壤。

Organic carbon compositions were studied in Greenhouse soils in Dongling of Shenyang.The results showed that the amount of non-humus carbon,humus carbon and its compositions were improved with the organic matter increasing,and was respectively 1.61~2.45 and 1.08~2.27 times of that in field soils.Compared with the field soils,the percentage content of non-humus to total organic matter in Greenhouse soils was lager.The water floating substances carbon to total organic carbon in Greenhouse soils was 1.19~1.65 times of that in field soils,but water-soluble carbon account for total organic carbon in Greenhouse soils and field soils were all about 2%.The humic acid carbon and humin carbon account for total organic carbon increased with increasing organic carbon,however,the increase in humic acid carbon was less than humin carbon.The optical density curve slopes of extractable humus and humic acid,E4/E6 values and △logK values were all lower than that in field soil,indicating that molecular complex degree of extractable humus and humic acid were lower than that in field soils.