Response Of Soil Ciliate Community Characteristics To Environmental Factors In North Mountain,Lanzhou City

Soil animals are an important part of the ecosystem and have a stable and inseparable relationship with environmental factors.The composition of the community structure of the soil animal community,species number,and individuals number can respond to changes of environmental factors.In order to understand the soil restoration status of the Greening Project at north mountain in Lanzhou City,soil samples were taken in four seasons of spring,summer,autumn and winter in April,July,October and December 2016.Samples include Fraxinus chinensis forest,Populus alba Var.Pyramdalis forest,Platycladus orientalis-Caragana korshinskii forest,and Amygdalus davidiana forest total of 4 Individual forests,and Artemisia brachyloba-shrubs slopes,barren slopes,have a total of six samples in Luojiu Highway Greening Project area.Then study the composition and structural characteristics of the soil ciliate community.This study can provide basic data for the study of soil animals and soil environmental quality,and at the same time provide scientific basis for the protection and restoration of two mountain ecosystems in Lanzhou City.The study found:(1)A total of 157 species of 62 genera and 39 families of soil ciliates were identified in this study.There are 10 classes,21 orders,34 families,44 genera,80 species in spring.In summer,there are 10 classes,21 orders,38 families,54 genera,104 species.There are 10 classes,20 orders,36 families,47 genera and 87 species in autumn,and 10 classes,20 orders,33 families,39 genera,70 species in winter.The first dominant species of soil ciliates in the four seasons was Sparidae,and the dominant species were Colpoda inflata and Colpoda patella.(2)The abundance,species number and diversity index of soil ciliates were the highest in summer,and the winter was the lowest.In the four seasons,the soil ciliates communities were less affected by the differences between plantations,and the differences between plantation and control sites were more significant.The similarity between plantation and control sites was low,and there was no significant similarity between plantations.The abundance,species number and diversity index of soilciliates in plantations were higher than those in the control points in the all seasons;The difference in the species number and diversity index between Fraxinus chinensis Roxb forests and Populus alba forests and other seasons was most significant in summer.The soil ciliate abundance was most significant differences with other seasons in winter,with little difference between the four seasons of the control sample.In the four seasons,the C/P coefficient of the rtemisia brachyloba-Shrubbery slope is the highest,and the C/P coefficient of the wilderness slope is the highest in the autumn,and the C/P coefficient of the poplar forest in the spring,summer,and autumn are all lower.Affected by the long-term maintenance of humans,there is rich in soil ciliates species of City North mountain Luojiu highway afforestation project area in Lanzhou.The environmental quality of plantation forests was significantly higher than that of the control sites,and the environment in summer and autumn was significantly better than that in spring and winter.(3)Compared with the control sites,the species distribution and individual number distribution of soil ciliates and the environmental factors were more likely to be plantation sites.The correlation between plantation and environmental factors in the four seasons was high.The semi-barren slope of Artemisia angustifolia in spring has a high correlation with soil environmental factors,and there is no significant correlation between desert slope and environmental factors.In addition to the strong positive correlation between summer slope and soil electrical conductivity,the summer,autumn and winter control points are similar.There was no significant correlation between environmental factors and soil ciliates.Environmental factors have a clear response to the environmental quality of the sites.(4)Soil total nitrogen,total phosphorus,organic carbon,water content,temperature and electrical conductivity are the main factors that affect the stability of soil ciliate community structure.With seasonal changes the soil ciliate distribution is also affected by environmental factors: soil temperature and soil electrical conductivity are the main environmental factors affecting the distribution of soil ciliate species in spring.Total phosphorus,bulk density and pH are the main factors affecting the distribution of individual number of ciliates in spring.Soil totalphosphorus,moisture content,electrical conductivity and soil temperature are the main factors affecting the species number distribution and individual number distribution of soil ciliates in summer;In autumn,soil temperature,electrical conductivity,total phosphorus,total nitrogen and organic carbon are the main factors affecting the distribution of soil ciliate species,and the main environmental factors affecting individual number distribution are soil temperature,pH,organic carbon,total nitrogen,and electrical conductivity.In winter,the main factors affecting the species number distribution and individual number distribution of soil ciliates are soil temperature,electrical conductivity,total phosphorus and pH.(5)The soil ciliates of different taxa have differently respond to environmental factors.Such as Cohnileme bidae and Urostylidae with soil nutrient elements and water contentin in spring,Cyclidiidae with pH and soil bulk density in summer,Halteriidae,Chilodonellidae,Keronidae with soil conductivity in autumn,Blepharismidae,Euplotidae,Halteriidae,Holophryidae with pH,Trachelophyllidae,Pseudomicrothoracidae,Tetrahymenidae with soil moisture,Prorodontidae with soil total phosphorus,Urostylidae with soil temperature in winter,there is a strong response between these soil ciliates and environmental factors.The distributions of Plagiocampidae in spring,and Enchelyidae,Spodoptera in summer,and Loxodidae in autumn are all not affected by soil environmental factors.The amount of a limiting factor in the soil environment affects the response of soil ciliates to other environmental factors.