Silicon Fertilizer Response Of Several Slag Mucks In Paddy Soil

Applying silicon fertilizer could improve soil silicon fertility, increase yield of rice, and improve quality of rice. Moreover, some problems about place for slag mucks and environmental pollution could be resolved by producing silicon fertilizer with slag mucks. So making the study of slag mucks as silicon fertilizer was significant. Silicon liberation characteristics in soil and their effect factors after applying slag mucks, effects of slag mucks application on silicon supplying capacity of paddy soil and silicon nutrition status of rice, and feasible indexes of slag mucks as silicon fertilizer were studied by incubation experiments and pot experiments, with a acid paddy soil in northern region of China and 5 kinds of slag mucks. The main results were as follows:1. Blast furnace slag A, blast furnace slag B, and blast furnace slag F all belonged to typical Si-Ca slag, as fly ash H belonged to Si-Al-Fe slag, and diamond slag J belonged to Si-Mg-Al slag. Alkalinity of blast furnace slag A, blast furnace slag B, and blast furnace slag F were over 1, so they were all alkaline slag. But alkalinity of fly ash H and diamond slag J were under 0.1, they were acidic slag. Contents of available SiO2 and citric SiO2 in blast furnace slag A, blast furnace slag B, and blast furnace slag F were all more than those in fly ash H and diamond slag J.2. Under flooded condition, silicon liberation kinetics behavior of soil could be expressed as equation y = kxm. For some treatments applied slag mucks, silicon liberation velocity and silicon liberation accumulation amount of soil was improved significantly, and pH of balanced solution increased. Contents of Ca2+ and Mg2+ increased significantly, and contents of Fe3+ and A13+ decreased significantly by applying slag muck A and slag muck B. Moreover, there were significant positive linear correlations between pH of balanced solution and silicon liberation accumulation amount, between total liberation accumulation amount of calcium and magnesium, total liberation accumulation amount of iron and aluminium and silicon liberation accumulation, amount, between ks, (means silicon liberation velocity) and kca (means calcium liberation velocity). There were very significantly positive exponential correlations between silicon liberation accumulation amount in 127 days and two parameter, mass coefficient(K) and alkalinity.3. For CK treatment, its soil pH was high, and contents of water-soluble silicon and active silicon were low compared with primitive soil. By applying slag mucks, content of water-soluble silicon decreased significantly and was lower than that of CK treatment. But contents of active silicon and available silicon all increased, and their increasing trends were more and more obvious with increasing dosage of slag mucks. More silicon nutrient was absorbed by rice after slag mucks application, and effects of slag muck A and slag muck F were better than that of slag muck B, effects of slag muck H and slag muck J were not obvious. There was a significant positive logarithm correlation between percentage increases of SiOi in rice and dosage of slag mucks, but content of silicon in rice and yield of rice was not interrelated.4.There was a significant positive power correlation between contents of available silicon of slag mucks extracted by HaO, 0.5mol.L-1 HCl and 2% citric acid and ap, but universality and optimum of those measuring means was not confirmed. There was a very significantly positive linear correlation between silicon liberation accumulation amount in 127 days and ap. There were very significantly positive logarithm correlations between two parameter, mass coefficient (K) and alkalinity, and ap. Silicon liberation accumulation amount in 127 days, K and alkalinity could be used to evaluate silicon availability of slag mucks well, and it was relatively simple and convenient to determine K and alkalinity.In conclusion, silicon fertilizer response of slag mucks were evaluated well by methods above-mentioned, silicon supplying capacity of paddy soil and...