Agricultural Resource Recovery For The Sediment Of Guanting Reservoir

The feasibility of agricultural utilization for the sediment was appraised, and the scheme of texture adjusting and harmful substance removing was advanced through the analysis for the properties of physics and chemistry of the sediment of Guanting reservoir in this research. The adjusting result for the properties of physics and chemistry of the sediment was tested in the course of potted plant test. The feasibility that the sediment was utilized as planting soil was further researched in field tests finally.The analysis results for the properties of physics and chemistry of the sediment were as followings: the structure of the sediment was denser, and the permeability was worse because its volumetric weight was higher and its porosity was lower. At the same time the content of reductive matter in the sediment was higher too. Only the content of Cd of the heavy metal in the sediment exceeded the secondary standard of environmental quality of the soil (GB15618-1995 ) in 0.86 times. Meanwhile, the content of the six kinds of metal paid close attention to were all below the corresponding limit of controlling standard of agricultural sludge(GB4284-84), and the potential ecological risk degree of the sediment was "low". The content of O.M., TN, TP, and Olsen-P in the sediment could meet the demand of the nutrient for the plants.The results of texture adjusting for the sediment showed: the total amount of the reductive matter of the sediment reduced by 82% while it was piled up naturally for 50 days. The volumetric weight of the sediment could be reduced, and its porosity could be improved while the sediment was mixed with the natural soil by the ratio of 1∶1 or 1∶ 2 in bulk, or the straw, 5% the bulk of the correspondinging sediment, CaO, 0.5% the bulk of that, the peat, 6.7% the bulk of that was added sequentially again.The results of the field tests showed: the growth of the plants was good in different treatments, and the content of O.M. of original soil all could be improved in different treatments. But the change for the content of N,P was not remarkable. The second treatment, i.e. mixed the sediment with soil and straw, could meet better environmental and economic benefit.