| There have lots of microbes in the natural soil, and they can forecast sensitively the changes of soil environment, for example, the change course of soil organic matter. So, soil biological activity is regarded as a sensitive index to measure soil quality. Research of soil microbes and biological activity can reveal the law of soil matter metabolism and fertility development, furthermore offer important theoretical reference value for soil ecological environment.Long-term locating experimentation has the potentiality of explaining problem but short-term experimentation has not. Long-term locating experimentation can overcome the influence on response to fertilizer of climate and annual variation, and research systematically the effect of fertilizer on the yield and quality of crop and the different of fertilizer system. At the same time, it can offer location for researching the effect on soil biology property of different fertilizer system.The property and substance component of long-term different fertilization soil have obvious changes, so soil biological activity accordingly change.This study researches systematically the effect on soil biological activity of 25 years' continuous different fertilization, from soil microbial biomass, soil microflora, soil biochemical impact intensity and soil enzyme activity. It studies the ration of fertilization and soil fertility, thereby it can offer scientific basis for getting at the impact of microbes in soil fertility adjustment, drawing up reasonable soil fertilizer system, accelerating reasonable soil ecologic circulation and lasting development agriculture.The results of this experimentation show:1. Compare with the soil before the experiment, at the ecologic condition of crop rotation (wheat-corn), soil fertility and the yield (wheat + corn) of long-term no-fertilizer treatment keeps stability. This shows that at the experimentation condition the central factor of soil fertility is not changed obviously, soil can maintain the turning over of inherent productivity function, and behave lasting productivity.2. Every index of biological activity of 25 years' continuous fertilization (inorganic fertilizer and inorganic fertilizer combined with organic fertilizer) soil is greater than no-fertilizer soil. For instance, the quantity of soil microbial biomass carbon, germ, actinomyces, fungus, ammonifiers, nitrogen-fixing bacteria and nitrifier, and the activities of soil unease, alkaline phosphatase, invertase and hydrogen peroxidase, and the intensity of soil nitrification, cellulose-decomposition, and ammonification rise respectively 5.45%～49.75%, 95%～298.33, 14.52%～203.63%, 74%～907.49%, 99.15%～542.88%, 91.75%～2725%, 59.49%～684.81%, and 4.89%～40.78%, 10.62%～28.2%, 50.48%～149.03%, 0.08%～1.29%, and 56.78%～388.39%, 25.52%～98.64%, 41.67%～404.17%.Inorganic fertilizer can accelerate the growth of crop rhizotaxis, and raise the quantity of soil organic matter, thereby promote the activity of soil microbes. Organic fertilizer brings lots living microbes, carbon source and energy source, so it can accelerate well the growth of soil microbes.3. The effect of inorganic fertilizer combined with organic fertilizer (corn stalk and animal manure) is better than inorganic fertilizer. For instance, the quantity of soil microbial biomass carbon, fungus, and nitrogen-fixing bacteria, the activities of soil unease, and the intensity of soil cellulose-decomposition rise respectively 21.86%～42.01%,490.44%～818.09%, 787.5%～1373.27%, 6.66%～21.78% and 2.09%～39.86%.It because that long-term reasonable application of inorganic fertilizer combined with organic fertilizer can supplement organic carbon source and improve soil physical and chemical property. It can offer good environment condition for soil microbes and soil animal, furthermore stimulate and raise the activity of soil microbes. So application of inorganic fertilizer combined with organic fertilizer can get preferable effect.4. The effect of animal manure is better than corn stalk. The reason...
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