Study On Correlations Between Am Fungi And Soil Factors

Mycorrhizas are sumbiosis that formed from plant roots and soil fungi. More than90%of terrestrial flowering plants are able to form mycorrhizal symbiosis with soil fungi. Arbuscular mycorrhiza (Arbuscular mycorrhizas, AM) is a symbiont which fungal infection of plant root formed. As an important class of soil microbe, the microbial diversity of arbuscular mycorrhizal fungi (AMF) and symbiosis with plants are important indicators to assess soil quality and ecological environment.Daliuta coal mine is located at Daliuta town of Yulin City, which is in Inner Mongolia region bordering, Shaanxi. It located in the transition zone and the Mu Us Sandland Loess Plateau, the climate is dry, water is short, ecological environment is extremely fragile. Coal mining is more severe in the region. In this paper, we choose Daliuta hard-soil and sand-soil subsidence as research plots, non-subsidence as a control to study coal mining subsidence’s effect on soil AM fungi diversity, soil enzyme activities, microbial quantity and soil properties, in order to explore the impact on the ecosystem for mine construction and land vegetation, to provide a theoretical basis for rehabilitation. The main findings are as following:1. We collected nine families,22genera and27species of plants in Daliuta coal mine. Among them there are8genera and9species of Gramineae, Leguminosae has4genera and7species, Asteraceae has2genera and3species, Verbenaceae has1genus and1species, Labiatae has1genus and1species. Liliaceae has1genus and1species were all mycorrhizal plants. Chenopodiaceae has3genera and2species Euphorbiaceae has1genus and1species, Geraniaceae has1genera and1species were not infected by AM fungi. The proportion of mycorrhizal plants in Daliuta coal mine is81.48%.2. We isolated7genera and19kinds of AM fungi from the sample sites in Daliuta coal mine, The species number of Glomus is the most. There are7genera and9species in subsidence’s contrast region. There are5genera and9species in subsidence’s region. In sandy soil, there are6genera16species. In hard soil, there are6genera12species. The spore density is39.00/100g in subsidence region,54.24/100g in subsidence’s contrast region. In sandy soil, it is45.13/100g.In hard soil, it is48.10/100g.With time of exploiting, the trend of AM fungal diversity is increased in subsidence region, which is contrary in subsidence’s contrast region. The spore density in both of subsidence region and subsidence’s contrast region is increased, relative abundance is increased too.3. The soil in sample sites is alkaline. The differences between soil water, pH, organic matter, total nitrogen, available nitrogen, total phosphorus, available phosphorus, total potassium, available potassium were significantly different. However, the soil water in2004sample sites, total nitrogen in2011sample sites have no significant differences between subsidence region and subsidence’s contrast region. With the time of exploiting, soil water is decreased, pH is decreased, organic matter is decreased, the total nitrogen is increased, the available nitrogen increase in the first and decrease after, total phosphorus is increased, available phosphorus is decreased, total potassium is increased, available potassium is decreased. The soil properties has no obvious trend between different soil type. In the same year, the indicators of soil properties in the subsidence’s contrast region are higher than which in the subsidence region.4. The activity of soil catalase and urease in subsidence region is higher than which in the subsidence’s contrast region. With the time of exploiting, catalase activity increased, while invertase and urease is not obvious. Sandy catalase, invertase activity is higher than the hard soil, and urease is not obvious.5. The number of soil microbe varies in different sample sites. The number of bacteria, fungi decreased with the time of exploiting increasing, which is not obvious in actinomycetes. In the same year, the number of microbe in subsidence’s contrast region is higher than which in the subsidence region. The number of bacteria and fungi in sandy soil is higher than which in hard soil, while this trend of actinomycetes is not obvious.6. AM fungi’s species richness abundance has significantly negatively correlation with the value of soil organic matter and available phosphorus (P<0.05), has significant positive correlation with the number of actinomycetes(P<0.01).The total nitrogen, total phosphorus, nitrogen content, the number of bacteria and fungi, catalase, urease, invertase activity is not significantly related with AM fungi’s species richness abundance. Spore density and soil factors are not significantly related.