Plant Diversity And Soil Nutrient Characteristics Of Typical Forest Communities In Taipinggou National Nature Reserve,Heilongjiang Province

Forest is very important component of the global ecosystem,with multiple functions such as water conservation,air purification,wind prevention and sand fixation,and are crucial for maintaining the ecological balance of the planet and the survival and development of humans.Currently,the research on forest plant diversity has become a hot topic in the field of biodiversity research.The Taipinggou National Nature Reserve in Heilongjiang Province has excellent natural ecological conditions,diverse forest types,and well preserved resources.Currently,a natural protection system integrating resource protection,scientific research monitoring,public education,and sustainable development has been formed.However,what is the diversity of forest plants in the reserve? What are the soil nutrient characteristics of different forest communities? What environmental factors affect the level of forest plant diversity in the region? This study focused on four typical forest communities in the Taipinggou National Nature Reserve,Heilongjiang Province,namely,spruce fir korean pine forest,Betula platyphylla forest,Populus davidiana forest,and Quercus mongolica forest.The research and analysis results indicate that:1)There are 167 species of plants belonging to 61 families and 123 genera in the four community types.The total number of plant species in the four forest communities is as follows: Populus davidiana forest>Quercus mongolica forest>spruce fir korean pine forest>Betula platyphylla forest.The vertical structure of the forest community is significantly stratified,with obvious dominant species in the tree layer,and the important value of dominant species is much greater than that of other associated species.The species important value in the shrub layer and herb layer are relatively scattered.The species richness of the tree layer and shrub layer of the four community types is lower than that of the herb layer.The total richness of the spruce fir korean pine communities is mainly affected by the joint effects of the tree layer and herb layer,while the total richness of the remaining three communities is mainly affected by the richness of the herb layer.The species diversity index of spruce fir korean pine communities is higher than that of the other three communities except the weeding layer.The species richness index,diversity index,evenness index and dominance index of different forest community types have obvious differences.The more complex the community structure,the more species composition,the less obvious the dominant species,and the more abundant the co dominant species,the higher the species diversity index;On the contrary,the simpler the forest type structure,the more obvious the dominant species of the community,the lower the various indicators.2)The community characteristics are quantified from multiple indicators such as DBH,tree height,stand density,canopy density,shrub height,and herb height.The forest community characteristics have an important impact on plant diversity.From the comparison of tree,shrub,and grass,the tree layer has a greater impact.Redundancy analysis shows that canopy density,DBH,and stand density are significant factors causing diversity changes.3)Soil nutrients have an important impact on plant diversity.From the comparison of four different forest communities,the soil water content and soil total nitrogen content in this study are higher in the Betula platyphylla forest and spruce fir korean pine forest,while the Populus davidiana forest and Quercus mongolica forest are lower,which is opposite to the level of plant diversity in their herb layer.Redundancy analysis showed that soil total carbon,soluble carbon,nitrate nitrogen,and soluble nitrogen were the main soil driving factors for plant diversity in the Populus davidiana forest community in the study area;Soil water content,soluble carbon,ammonia nitrogen,total nitrogen,microbial nitrogen,total carbon,and soluble nitrogen are the main soil driving factors for plant diversity in the Betula platyphylla forest community in the study area;Soil nitrate nitrogen,ammonia nitrogen,soluble nitrogen,and total carbon are the main soil driving factors for plant diversity in spruce fir korean pine forest communities in the study area.Soil soluble nitrogen and total carbon are the main soil driving factors for the diversity of tree and herb layers in the Quercus mongolica forest community,while other soil physical and chemical properties have no significant impact on the plant diversity of various forest types.