Correlation And Response Of Leaf Functional Traits Of Woody Plants At Different Altitudes In The Southeastern Of Motianling Northern Slope

Plant functional traits reflects the response of plants to the changes of living environment,but also have a certain impact on ecosystem functions.The method based on functional traits has been widely used and developed in the study of community diversity maintenance mechanism in recent years.Leaf functional traits of plants were found to be closely related to plant biomass,plant uptake and utilization of light,water and nutrients.And it can reflect the ecological adaptation of plants in order to minimize the adverse effects of the environment.This paper selects five leaf functional traits such as specific leaf area,leaf dry matter content,leaf carbon content,leaf nitrogen content and leaf phosphorus content to research plant functional traits of woody plants in the southeastern of Motianling northern slope.The purpose of this study was to explore the relationship between leaf functional traits and the effects of altitude on leaf functional traits;Meanwhile,the similarities and differences between leaf functional traits of different functional groups in different functional groups were compared.The main conclusions of this study are as follows:(1)The change range of the property values of the leaf functional traits of woody plants in the southeastern of Motianling northern slope was larger,which reflected the adaptation difference for different plant to the environment.The change range of specific leaf area and leaf carbon content was the largest.The second were leaf dry matter content,leaf nitrogen content and leaf phosphorus content.However,the variability of leaf carbon content was weak,Other leaf functional traits such as leaf dry matter content and leaf nitrogen content were moderately variable.And the specific leaf area and leaf phosphorus content were strong variation.(2)There was a negative correlation between the specific leaf area and leaf dry matter content and leaf carbon content of the woody plants in the study area,and the correlation between the specific leaf area and leaf carbon content was significant(P<0.05);There was a significant positive correlation between the specific leaf area and leaf nitrogen content(P<0.01).But there was no significant positive correlation between the specific leaf area and leaf nitrogen content.There was a significantpositive correlation between leaf dry matter content and leaf carbon content(P<0.05),but the significant negative correlation between leaf dry matter content and leaf nitrogen content(P<0.01).There was a negative correlation between leaf carbon content and leaf nitrogen and phosphorus content and its correlation with leaf phosphorus content was significant(P<0.05).There was a significant positive correlation between leaf nitrogen content and leaf phosphorus content(P<0.05).(3)Through analyzed the changes of leaf functional traits in the study area with the change of elevation gradient: the specific leaf area and leaf dry matter content showed the trend of decreasing first and then increasing with the elevation gradient increasing.With the increase of altitude,the leaf carbon content showed an increasing trend.The leaf nitrogen content decreased with the elevation,but the trend was not obvious.The leaf phosphorus content showed a trend of increasing first and then decreasing with the increase of altitude;(4)There were differences in leaf functional traits of different living plants.The specific leaf area and leaf nitrogen content of the shrub was higher than those of the arbor.However,the leaf dry matter content,leaf carbon content and leaf phosphorus content of the arbor was higher than shrub.At the same time,the correlations among in leaf functional traits of different plant types showed different change trend.There was a significant negative correlation between the specific leaf area and leaf carbon content of the shrub in the 0.05 level.And there was a positive correlation between the specific leaf area and the leaf nitrogen content.However,leaf carbon content was significantly correlated with leaf phosphorus content at 0.05 level.There was a significant positive correlation between leaf nitrogen content and leaf phosphorus content at 0.01 level;For arbors,there was no significant correlation among in leaf functional traits.And there was a significant positive correlation between leaf dry matter content and leaf carbon content at 0.05 level.(5)The specific leaf area of arbors and shrubs increased with the increase of altitude,and the trend of the changes of the specific leaf area showed decreasing trend firstly and then increasing gradually.The leaf dry matter content of arbors was less than the shrubs.The leaf dry matter content of arbors and shrubs showed a trend offirst decrease and then increase with elevation increasing.With the increase of altitude,the leaf carbon content of arbors and shrubs showed a slow increasing trend.The leaf nitrogen content of arbors showed decreasing trend firstly and then increasing with the increase of altitude,while the leaf nitrogen content of shrubs showed decreasing trend.The leaf phosphorus content of arbors increased with the increase of altitude,while the leaf phosphorus content in the shrubs showed a trend of increasing firstly and then decreasing with the increase of altitude.(6)The results of cluster analysis showed that it can be divided into five different functional groups in the southeastern of Motianling northern slope,and termed,A,B,C,D,E functional groups.The A functional group was dominated by deciduous plants,and the plants in the functional group were mostly found in hillside or valley scrub.B functional group plant leaves were leathery or thinly leathery,all plants were fond of light,slightly resistant to drought.C functional groups leaves were lanceolate,obovate or oval.D functional group leaves papery,lanceolate,mostly grown in the valley side,valley bottom,hillside,the functional groups of all plants can be used as medicine.E functional groups dominated by shrubs.Most plants growed in the valley in the forest or thickets on slopes,and some plants growing in shady slope.The single factor analysis of variance showed that there were the most significant differences among in the specific leaf area,leaf dry matter content,leaf nitrogen content and leaf phosphorus content in each functional group,and there was significant difference in leaf carbon content among in different functional groups.The order of the N/P value of five functional groups was A functional group >B functional group >D functional group >E functional group >C functional group.The N/P values of C,D and E functional group were all less than 14,which indicated the plant growth in these three functional groups was limited by the available nitrogen and the response to nitrogen was stronger.The N/P value of the A functional group was greater than 16,which indicated that the plant growth in the A functional group was mainly limited by the available phosphorus,and the response to phosphorus was stronger.However,the N/P value of the B functional group was higher than 14 and less than 16,which indicated that the plant growth in the B functional group waslimited by the available nitrogen and phosphorus contents.(7)In short,the contents of nitrogen and phosphorus in woody plants in the southeastern of Motianling northern slope were higher and the N/P value was 14.969.This situation showed that the growth of woody plants in study area was mainly limited by the available nitrogen and phosphorus contents.