Study On Microorganism And Enzyme Activity Of Different Sandy In Erdos

This dissertation studied on the three sandy in Erdos, Inner Mongolia. They are sand-flowing dune, semi-fixed sand and fixed sand. In the three sandy, seasonal variation and vertical distribution of soil nutrient, soil microorganisms and soil enzyme activity and so on were studied systemically and embedly. The main research results were as follows:1. In sand-flowing dune,semi-fixed sand and fixed sand, the content of organic matter, total nitrogen and total phosphorus under ground 1cm was higher than that in the 1～20cm soil layer, but the content total kalium was on opposite. The soil character was alkalescence. Organic matter and total nitrogen contents in fixed sand showed the highest in spring.2. In three plots, the quantity of bacteria was predominant, actinomyces was the next, and fungi was the least among composition of soil microbes. The soil microorganism showed an significantly increasely with plant age. And the quantity of bacteria, actinomyces, fungi and total microbes were fixed sand＞semi-fixed sand＞sand-flowing dune.3. Season variation of quantity of total microbes and the three types of soil microorganisms was similar in semi-fixed sand and sand-flowing dune, but it was very different in fixed sand. In fixed sand, the quantity of bacteria and actinomyces was the highest in spring, but the quantity of fungi was the highest in winter, and the least in autumn. In semi-fixed sand, the quantity of bacteria was higher in spring, autumn and winter than in summer, but actinomyces was highest in spring, the fungi was no remarkable seasonal dynamics.4. Vertical distribution of the three types of soil microbes in sandy was different. The number of bacteria in sand-flowing dune was increased with increasing of soil depths. But it was decreased in semi-fixed sand and fixed sand. The quantity of actinomyces was similar to bacteria which in fixed sand and sand-flowing dune. But it was highest in the 1～10cm soil layer, and least in 10～20cm soil layer in semi-fixed sand. The quantity of fungi was also no remarkable vertical distribution.5. In fixed sand and sand-flowing dune, the percentage of bacillus sp. was highest in winter, and the second was in summer, and in that time the quantity of bacteria was low. But in semi-fixed sand it was highest in winter, and the second was in spring, this was the same trend of quantity of bacteria.6. The number of 2-1-1,2-1-4,2-1-10,2-1-14,2-1-15 were identified by physiological & biochemical reactions results and morphological characteristics, biolog and16s rDNA sequence. The result were Bacillus cereus, B. maroccanus, B. megaterium, B.subtilis, B.licheniformis.7. The activity of Alkali-phosphatase was weakened with increasing of soil depths, and shows the highest under ground 1cm, the lowest level in summer. The season variation and vertical distribution of the activity of Urease and Polyphenol-oidase were inapparent. In sand-flowing dune, the activity of Urease was signification positive correlation to Alkali-phosphatase. In fixed sand, the activity of Polyphenol-oidase was signification positive correlation to Alkali-phosphatase.8. The three types of soil microorganisms were signification positive correlation to the content of organic matter and total nitrogen and the acticity of Alkali-phosphatase. And those were remarkable to the activity of Polyphenol-oidase and Urease. The number of bacteria and total microbes were signification positive correlation to the content of total kalium. But the number of actinomyces and fungi were indistinctive correlation to the content of total kalium.