| In order to solve the problem of soil resources shortage in Binhai saline area and achieve sustainable development, empolder a new, avail environment medium. Use fly ash, calcium carbide dust, dredged sand on the modification of dredged sediment to configurate a new green matrix. And though Tall Fescue pot experiment the calcium superphosphate, cow dung, sludge fertilization were obtained.1.Study the physical and chemical properties of three materials which are dredged sediment, fly ash and calcium carbide dust and leaching cycle desalination through indoor washing desalination experiment using{3,2}simplex lattice design. After desalting pH value of all treatment of minimum 10.56,maximum 12.48,are not suitable for plant growth, so the results were not optimized, and optimization modeling; Study the relationship between the proportionment of three materials which are dredged sediment, dredged sand and calcium carbide dust and leaching cycle desalination through indoor washing desalination experiment using{3,2}simplex lattice design. Scheffe mathematical model was established to study relationship between the three materials and leaching cycle desalination. By computer the Scheffe mathematical model simulating and optimizing, combining with actual needs and desalination rate, water, pH change trend, whether basified off etc, identify the best volume ratio that dredger sediment:dredged sand:calcium carbide=0.55:0.40:0.05.2.This test is designed to measure water & salt movement and physical & chemical properties after desalting and desalted alkalization of artificial soil, which was mixed dredged sediment, dredged sand and calcium carbide waste with the ratio of 0.55:0.40:0.05, were studied under steadily infiltrated condition. The results showed that three salt peak periods were found:the forming stage, the moving down stage and the disappearing stage. A linear correlation (y=0.0028x-3.2675 (R2=0.9124)) was found between the water used and desalination depth, from which the approximate amount of water required in leaching can be drawn. After desalination ionic components were Na+, Ca2+-Cl-, CO32- to Ca2+-HCO3-, SO42- at the depth of 0-60cm and Na+, Ca2+-Cl-, CO32--to SO42-at the depth of 60-140cm. After desalination the texture of the mixed matrix was of fine sand soil and no desalted alkalization was found. Based on our results, the mixed matrix can use as a plant growth medium and the lower fertility showed that soil fertilization was an important measure.3. Based on pot experiment, the experiment used regression design with three factors and five levels, studied coupling effect of calcium superphosphate, cow dung and sludge to the growth of Tall Fescue. The results are as follows:Tall Fescue in all treatments grew well and good uniformity. pH values of all treatments are suitable for plant growth; all treatments organic content of 1.5g/kg, and reached a high level; sludge is the most effective factor effecting biomass; interaction between factors is not obvious. Based on optimal mathmetical models,the target biomass was over 6.40kg/m2,fertilizer rate was calcium superphosphate 21.17-29.64g/kg, cow dung 43.97-76.29g/kg, sludge 159.11-188.13g/kg.So, matrix which mixed dredged sediment, dredged sand and calcium carbide waste with the ratio of 0.55:0.40:0.05 use in landscaping was entirely feasible. For future, we should search after more and more truth to make use of municipal solid refuse such as calcium carbide and sludge more effectively. |
