Analysis Of Leaf Functional Traits Of 13 Species Trees In Northwest Fujian Province

Functional traits of plant leaves reflect the adaptation of plants to the environment.The study of functional traits of plant leaves is of great significance for us to understand the strategies adopted by plants in the face of environmental changes,the differences and connections between different functional traits,and the trend of changes in leaf functional traits of different life forms.In this study,the functional characteristics of the leaves of 13species tree in northern Fujian were used as the research object.The specific leaf area,water use efficiency,carbon,nitrogen and phosphorus content,utilization efficiency and reabsorption efficiency of the leaves of different life types were analyzed by measuring the carbon,nitrogen and phosphorus content,carbon isotope abundance(?¹³C)and leaf area,the correlation between Leaf functional traits.The research results show that:?1?specific leaf area of plant leaf is mainly affected by plant life-form,specific leaf area is significant difference between different life tree species,2 species of evergreen conifer SLA is 4.73cm²/g,7 species of evergreen broad leaved tree species of SLA is 7.62 cm²/g,4 kinds of deciduous broad leaved tree species of SLA is 11.47 cm²/g,three kinds of SLA between the life tree value size of deciduous broad-leaf tree>evergreen broad-leaf>evergreen coniferous tree species.From conifers to broad-leaved species,from evergreen species to deciduous species,the specific leaf area of the species increased significantly.?2?there were significant differences in WUE between different life types:the average value of?¹³C of evergreen conifer species was-28.78‰,the average value of?¹³C of evergreen broad-leaved species was-31.15‰,and the average value of?¹³C of deciduous broad-leaved species was-29.87‰.The WUE of plants was usually greatly affected by genetic factors,but under repeated stress of drought conditions,plants reduced the influence of drought by improving WUE.?3?the concentrations of C,N,and P in the leaves of 13 species were 451.08mg/g,13.98mg/g,and 0.37mg/g,respectively,all lower than the average contents of C,N,and P in terrestrial plants worldwide.The values of C:N,C:P,and N:P were 35.30,1267.31,and38.94,respectively.In this study,the N resorption efficiency of evergreen conifer species,evergreen broad-leaved species and deciduous broad-leaved species were 13.05%,25.53%and 32.04%,respectively.P resorption efficiency was 67.85%,45.29%and45.17%,respectively.?4?the correlation of leaf functional traits showed that the specific leaf area of 13 tree species was positively correlated with nitrogen concentration,nitrogen resorption efficiency and nitrogen utilization efficiency.Leaf nitrogen content was positively correlated with phosphorus content,nitrogen reabsorption,nitrogen utilization efficiency and phosphorus utilization efficiency.There was a significant negative correlation between p concentration and p utilization efficiency.Nitrogen resorption efficiency is negatively correlated with nitrogen utilization efficiency and positively correlated with nitrogen/phosphorus ratio.P utilization efficiency is positively correlated with n/p ratio.?5?when specific leaf area and water use efficiency?WUE?showed negative correlation,maintain normal plant growth and development,habitat in the water supply level within the scope of tolerance in plants,plant is limited by moisture degree is beyond the scope of the plant tolerance,normal physiological activities is restricted,negative relationship between disappear,so we can through the presence or absence of this relationship,to determine degree of plant water restrictions.?6?under severe drought stress,plants increase their resistance to water stress by increasing phosphorus consumption,so as to reduce damage.Evergreen tree species can reduce the influence of phosphorus on water use efficiency through higher nitrogen use efficiency.The functional characters of leaves of plants in the experimental area showed obvious characteristics of phosphorus deficiency and water stress.Among the three life types,evergreen conifer species and evergreen broad-leaved species showed good adaptability to the local oligotrophic environment,while deciduous broad-leaved species showed drought stress and phosphorus deficiency.