官厅水库坝前疏浚底泥的理化特征和土地利用研究

Physicochemical Properties of Guanting Reservoir Sediment and Its Land Application

用环保疏浚船抽取官厅水库坝前表层底泥,在田间脱水池进行自然脱水,研究脱水后底泥的理化性质和污染物特征,底泥无害化处理方式和处理后底泥的土地利用效果.结果表明,官厅水库坝前疏浚底泥中黏粒含量高,容重高达1.89 g.cm-3,孔隙度只有23.8%,干后龟裂且非常坚硬,植物不能在上面生长.底泥中含有大量的还原性物质和速效性氮、磷,但重金属和有机氯农药含量均低于二级土壤环境质量标准.通过加入砂性土壤和作物秸杆等材料可以降低底泥容重和还原性物质含量,提高底泥的孔隙度并固持底泥中的速效性氮、磷.经过处理后的底泥可以成为良好的植物生长介质,玉米、苜蓿和杏树苗在上面生长良好.

Surface sediment of Guanting Reservoir was dredged up and dewatered in field, and pollutant and physicochemical characterizations were mensurated. The stabilization and agricultural land use of the sediment was also studied in the field. Results showed that the sediments have a higher clay content, bulk density （ 1.89 g·cm^-3 ） and lower porosity （23.8 % ）, higher deoxidize material and available nitrogen, phosphorus concentration. Heavy metal and organochlorinated pesticides concentration was lower than the class Ⅱ of national standard for soil. Stabilized the sediment with sand soil and straw could improve the physical property and decrease the concentration of deoxidize material and available nitrogen, phosphorus. Stabilized sediment could be a suitable medium for alfalfa, tree and corn growth and used for agricultural land.