Coupling Response On Functional Traits Of Machilus Pauhoil To Environmental Factors

China's subtropical region is facing global warming problems such as climate warning,nitrogen deposition and seasonal drought,and so on.Although the region has abundant forest resources,it has high sensitivity and uncertainty to environmental change.The future environmental change will affect forest plant functional traits,geographical distribution,community composition and even the ecosystem function,it have an important significant impact.The relationship between plant leaf functional traits and environmental factors in China is mainly concentrated in small-scale elevation gradients or large-scale plants of the same genus.In view of this,this paper studied the relationship between leaf functional traits and environmental factors by using the rare tree species Machilus pauhoi as the research object,and we are discussed that the strategies are adjusting to the different environmental conditions.In order to reveal the relationship between plant functional traits and environmental factors,which is helped us to understand the environmental changes effect on plant functional traits and plant traits adopted to strategy for ervironment changes.The results show:(1)Among the leaf traits in Machilus pauhoi:Parent leaves LNC,LPC,LDMC,LA.RWC,and LT were significantly higher than those of the undergrowth seedlings;seedling leaves and parent leaves SLA has obvious differences;There was a significant positive correlation between LPC and SLA,LNC and LPC in parent leaves.Forest seedling leaves found:SLA and LDMC,LPC and LNC very significant correlation,SLA and LPC,LA and LT,LT and LNC significant correlation.Forest seedling and common garden seedling leaf traits:Finding the significant differences between common garden seedlings and seedling leaf characters of the same provenance with a family.(2)The chemical stoichiometric ratio of nutrient components in parent and seedlings leaves:parent trees leaf content rang was higher than seedlings,C:P and N:P were lower than seedlings.Parent and seedling tress C,N,P contents was significant related to C:N,C:P,N:P.There was significant correlation among roots,stems and leaves.The natural forest leaves C contents was higher than the global level,but the content of N and P was lower than all regions and the global level,but C:N,C:P and N:P were significantly higher than the global level.(3)The leaf characters of Machilus pauhoi is showed some regularity with the change of environmental factors(average annual temperature,annual average precipitation,latitude and longitude).Significant correlation to forest seedlings LDMC,LT and the longitude and latitude,the leaf area was significantly correlated with>10 degree years accumulated temperature.The parent and seedling leaf traits with growth season(4-11 months)climate factors:Found that parent LNC and climatic factors have a closely related,and seedlings LNC,LDMC and LT correlated significantly with temperature related indexes.(4)Relationship between leaf nutrients,forest soil and environmental factors:Different forest seedling components have a significant effect on growth season climatic factors,Machilus pauhoi nutrition contents have a significant positive correlation between LNC,LPC and Latitude or longitude,but stems N,C:N and annual mean temperature,>10 degrees temperature significantly negative correlation.The root N:P was negatively correlated with annual mean temperature.Woodland 4 found in the soil layer of soil bulk density and>10 degrees temperature significantly or very significantly negative correlation.Soil bulk density and latitude and longitude were significant or extremely significant positive correlation.The contents of N:P,C:P and annual mean temperature or average temperature of January have a significant or extremely significant negative correlation.Gram positive bacteria and gram negative bacteria were closely related to environmental factors.(5)Soil physical or chemical and microbes properties was related to leaf traits:soil bulk density and water content decreased with increasing soil depth;soil pH increased with soil depth,soil C,N,P and C:P,N:P and C:N decreased with the deepening of soil depth,and the correlation between soil C,N,P and nutrient elements was significant,and the inter-element correlation was strong.The C and N contents in soil were significantly higher than those in soil The soil temperature,the average temperature and the national mean,and the soil P content was significantly lower than the national average temperature and soil temperature;soil physical and chemical properties and soil microbial and leaf functional traits have a certain relevance.(6)The stability characteristics of C,N and P in different components of seedlings:There was little changed in root stability index of seedlings,but leaf and stem stability index was greater than root;The stability index of root,stem and leaf were C elements higher than N,P the elements,and C:P,N:P were greater than P elements;Seedling stability index is greater than 1,Which was long-term adapted in site environment.