Effects Of Manure Combined With Inorganic Fertilizer On The Characteristic Of Soil Microbiology And Fertility

Over the years,the unreasonable using of chemical fertilizer in China has not only caused the low utilization rates of nutrition,the waste of resources and declining in qualities of agricultural products,but also leaded to the deterioration of soil characters and pollution of ecological environment,which seriously has hindered the development of sustainable agricultural.In order to utilize the manure of livestock and poultry effectively and improve outcomes of applying fertilizer under new situations and circumstances,the scheme of organic manure combined with inorganic fertilizer has been the focus of researching.Based on this,in Hailin farm,Heilongjiang province for two years of continuous cropping of corn test,under the condition of the same amount of nitrogen?combined application of organic fertilizer in autumn with chemical fertilizer in spring?,we designed 100%organic fertilizer?T1?,30%organic fertilizer+70%inorganic fertilizer?T2?,20%organic fertilizer+80%inorganic fertilizer?T3?,100%inorganic fertilizer?T4?and no fertilizer?CK?5 treatments in total to study the effects of applying organic fertilizer in autumn on three kinds of soil microorganisms number,SMBC,SMBN,nutrient,enzyme activities,and maize yields,and analyze the internal links among them.The results showed that:?1?Applying fertilizer could improve the amounts of soil microbial significantly,among which,the number of bacteria and actinomycetes increased by 16.38%²4.32% and 2.61%²4.32% respectively in organic fertilizer treatments 2 years later,while the increasing range of organic manure combined with inorganic fertilizer was bigger,and restrained the growth of fungi effectively in 13.41%¹3.41% meanwhile,that was convenient to be formed bacterial soil mostly,however,single chemical fertilizer and no fertilizer could promote the production of fungi,which increased the risk of soil borne disease.?2?Applying organic fertilizer in autumn has increased the contents of SMBC and SMBN significantly.SMBC increased by 11.32%¹8.01% in organic fertilizer treatments,but the increasing range of SMBN was small,but its effect was better than that of single chemical fertilizer,and shown a tendency of being accumulated with the fixed number of year,yet long-term single chemical fertilizer and no fertilizer showed reductive signs significantly.?3?Applying chemical fertilizer could improved the activity of urease significantly in early time,but organic fertilizer was dominant lately,and increased by 2.84%⁹.23% after 2 years,and 20% organic fertilizer treatment was the best;Single organic fertilizer and chemical fertilizer had no obvious significance on the effect of soil invertase activity,whereas combined application treatments improved 4.22%¹9.61% 2 years later.The activity of catalase increased by 7.65%¹5.49% in organic fertilizer treatments 2 years later,and the difference of between T1 and T2,T3 was not obvious,yet single chemical fertilizer had significant inhibitory effect on it;With fixed number of year of fertilization,organic fertilizer could improve the activity of cellulose significantly,and the range was 1.79%⁷.97%,while organic manure combined with inorganic fertilizer had more obvious effect than T1,apart from this,single chemical fertilizer and no fertilizer had little effect on it.?4?No fertilizer could cause soil nutrient to be reduced significantly,while applying fertilizer enriched the soil fertility in different degree,but organic manure combined with inorganic fertilizer raised the contents of total nitrogen and organic matter most obviously,and the effect of improving total phosphorus and total potassium was equal to single organic fertilizer,besides,organic fertilizer reduced the soil acidity significantly;SMBC/N and microbial could affect the activity of enzymes,and SMBC/N and the activity of enzymes showed positively correlation relationships with maize yields.?5?Applying fertilizer could improve the contents of NO₃-of 3 layers,and the nitrate of topsoil showed a downward trend with the growth period,especially mature period,at which 31-90 cm soil layer of T4 was 96.9%,39.1%,36.1% and 17.8% higher than CK,T3,T1 and T2 respectively;The correlation coefficients of seedling and filling stage between corn yields and the NO₃-accumulation of 0-90 cm layer were 0.925* and 0.904* individually,while elongation stage was 0.997**,and T2 and T3 had stronger abilities in providing nitrogen for maize than others meanwhile,besides,they had lowered the risk of environmental pollution to a great extent;Total corn yields showed T2>T3>T4>T1>CK in 2 years,and T2 was higher 57.34% and 4.59% than that of T1 and T4 respectively,which stabled yields effectively.