The Study On Soli Microbial Diversity Of Rare And Endangered Pinus Bungeana Zucc.et Endl

Pinus bunging Zucc.et Endl,chinese spciality and one of rare tree species,is exclusive trifoliate pine in East Asia.For its sun,loving,cold-resistant,drought Resistance barren-resistant,it can be able to grow in the different habitats,which is not only suitable for aforestation in barren hills,but also in garden afforestation.It has a number of uses.With the ability of anti-jamming to pollution of SO₂,HF and dust,it is aslo a special specics used in afforestation of Mine District.The study of soil microbial diversity is the component of the research of terrestrial ecosystem diversity. keeping up basic ecological process and life sustain system is the substance base of exist and development of human.microbial diversity,part of Biological Diversity of the Earth and complex forest ecosystem,plays an important role in the structure and function of whole ecosystem.So,the study of community structure and ecological distribution and species diversity will help us make deep discussion on the structure and function of soil microorganism,There are important theory and practice meaning in understanding the protection of Pinus bunging Zucc.et Endl,Construction of Ecological Environmemnt and Conservation of Biodiversity.Soil microbial diversity of different habitats was analyzed and discussed by ecoclogical view in the paper,incluing of community species,analysis of ecological characterstic of soil microbial community and diversity,relationship between the diversity of soil microorganism and environmental factors.The results indicated as follows:(1)Changes of Microbial Community StructureThe results showed that the microbial community is composed of 20 genera of 80 families,11 families,12 genera,in bacteria;2 families,2 genera,in actinomycetes;3 families,6 genera,in fungi.By investigation of the distribution status of soil Microbiota,we find the bacteria having higher hydrolytic ability takes up a large proportion.,of which Micrococcus,Bacillus was the kind of ascendant bacteria,the common is Nitrobacter,Pseudomonas,Agrobacterium.Pseudomonas only presented in tianshui samples.Because of the difference in environmental condition,amount and species of actinomyces varied.there are only two species in the whole,Streptomyces and Micromonospora,of which the dominant is Streptomyces,the rare specie is Micromonospora.The number of fungi was highest in sample 11,lowest in sampIe 14. In the all of fungi,Penicillium and Aspergillum is widely distributed,and Rhizopus is the second;Trichoderma and rnucor was respectively distributed in 10 samples and 11 samples,but Alternaria is present in sample 2.(2)The duster analysis of soil microbial community of Pinus bunging Zucc.et EndlThe samples of this text is from two climatic subregion which is in Tianshui and Longnan.The similarities among 20 smples are studied by using cluster analysis with Jaccard' s similarrity coefficients,the results are in agreement with Jaccard's similarrity analysis.According to results obtained from the cluster analysis based on similarity coefficients at generic levels,Houchuan and Jingtusi 2 are more isolated. The results coincide with Jaccard' s similardty analysis:The two samples in the same area show a notable similarity,but varied from some facters.The final result shows that there is good correlation between the species composition of microbes and the environmental conditions.(3)The study on the diversity of soil microbial community of Pinus bunging Zucc.et Endl20 diferent microbial community in the soil were analyzed and compared by species richness index,diversity index and evenness index.The result showed that Species Composition,Quantity Variation and Bio-diversities ect.of soil microbial community differed.There was positive correlation among the community index,while negative correlation between the dominate index and diversity index.The diversity index of different area displayed that Jingtusi＞Luoba＞Baohuqu.(4)Relation between siol microbial diversity and enviromental factersThere is a moderate relationship between Soil microbial diversity and organic matter;and a week relationship between soil microbial diversity and soil moisture.With the study of temporal-spatial distribution of siol microbial diversity,we found species richness index,diversity index and evenness index had a falling trend,and the downtrend was slighly different.From the perspective of succession,soil microbial diversity increased with time going.Soil microbial diversity not only was affected by soil organic matter,vegetation, seasonal change,but also by external factors,of which the human interference was the main factor.Under different human-caused disturbance,the result differed,Changes in microbial diversity confirm the hypothesis of intermediate disturbance,which is the basis of ecological variations of Pinus bunging Zucc.et Endl.