The Soil Microbial Characteristics In Different Vegetation Grasslands And The Relation Between Plant Growth And Soil Microbes In Songnen Plain

Songnen grassland locates in the eastern of Eurasian steppe zone, belong to salinization grassland, it is one of the most important natural pasture and the concentrated distribution area of saline-sodic soils in China. There are many differences from plant species to biomass in different plant communities, and it is a subject worthy for further study which the relations among plant communities, soil microbes and soil nutrients, soil salinity in different saline-sodic soils. In this paper, these were showed that the relationships between soil microbes and nutrients and classify the salinization grassland by clustering analysis, and the relations between soil biological and plant growth by means of collected the soil sample under different vegetation in Songnen Grassland, aim at providing theoretical basis for the development and utilization of saline-sodic soils in Songnen plain. The results were showed that: 1. The microbial characteristics in different vegetation soilsThere were some differences between soil microbial quantity under different vegetation,number of soil bacteria of Leymus chinensiscommunity was higer than Phragmites australiscommunity, Chloris virgatecommunity, Puccinellia chinampoensiscommunity, Saueda glaucacommunity and Baresaline-sodic respectively, 64.5%, 64.9%, 81.4%, 90.3% and 93.1%;the number of soil fungi of Leymus chinensis was higer than Phragmites australiscommunity 、 Chloris virgatecommunity、Puccinellia chinampoensiscommunity、Saueda glaucacommunity and Baresaline-sodic respectively, 16.4%, 66.0%, 80.2%, 85.0% and 90.5%;the number of soil actinomyees of Leymus chinensis was higer than Phragmites australiscommunity 、 Chloris virgatecommunity 、 Puccinellia chinampoensiscommunity 、 Saueda glaucacommunity and Baresaline-sodic respectively: 69.7%, 82.6%, 84.8%, 88.5% and 99.2%.There was some difference between soil enzyme activity under different vegetation,soil Catalase, Alkaline Phosphatase, Sucrase and Urease of Leymus chinensis community were has significant differences with other community,the order was:Leymus chinensis>Phragmites australis>Chloris virgate>Puccinellia chinampoensis>Saueda glauca> Baresaline-sodic spot. 2. The relations between soil microbes and soil nutrients, salinitiesThe correlation analysis between soil microbial number、enzyme activities and nutrient has indicated that: the soil bacteria、fungi and actinomyees has positive correlation with organic matter and total nitrogen, but has negative correlation with EC and ESP; Soil enzyme has positive correlation with organic matter and total nitrogen,but has negative correlation with p H、EC and ESP. 3. The vegetation was classified by using of soil indexesClustering analysis of comprehensive soil indicators such as soil salinity, nutrient and number of microbial showed that the Leymus chinensis was slight saline and alkaline land, the Phragmites australis and Chloris virgate was middle saline and alkaline land,the Saueda glauca、Puccinellia chinampoensisand baresaline-sodic soil was heavy saline and alkaline land. 4. The difference of biomass aboveground and nutrients under different vegetationThe plant biomass and nutrients has big difference under different vegetation.Phragmites australis community has the largest biomass above ground,Leymus chinensiscommunity and Puccinellia chinampoensiscommunity has the second place,Chloris virgatecommunity and Saueda glauca community has least biomass; plant nutrients above ground has indicated that: Phragmites australis community has highest concentration of plant total nitrogen,Saueda glauca community take second place,Leymus chinensiscommunity has minimal concentration; the total phosphorus of Chloris virgatecommunity has highest concentration,Saueda glauca community take second place,Leymus chinensiscommunity and Phragmites australis community has minimal concentration; the total potassium of Puccinellia chinampoensiscommunity has highest concentration,Leymus chinensiscommunity take second place,Phragmites australis community、Chloris virgatecommunity and Saueda glauca community has minimal concentration. 5. The relation of biomass above ground and plant nutrients with soil microbialnumber and soil enzyme activity under differert vegetationPlant biomass with soil fungi and Urease has positive correlation under differert vegetation,plant total nitrogen with soil actinomyees and Catalase has negative correlation; plant total phosphorus with soil fungi has negative correlation, with Urease and Alkaline phosphatase has negative correlation; plant total potassiun with Catalase has positive correlation, another has no correlation. 6. The relation of biomass above ground and plant nutrients with soil nutrients andsalts under differert vegetationPlant biomass with soil total phosphorus、available nitrogen、available potassium, CEC and organic matter has positive correlation under different vegetation, with EC has negative correlation, plant total nitrogen with soil total nitrogen and available nitrogen has negative correlation; plant total phosphorus with soil available phosphorus, p H, EC and ESP has positive correlation, with soil total phosphorus and CEC has negative correlation; Plant total potassium has positive correlation with soil available potassium.