| Plant functional traits refer to the formation of morphological,structural,physiological,ecological,phenological and other traits during plant growth.These traits are related to their own development also respond to changes in the external environment and affect ecosystem function to a certain extent.Taking Picea wilsonii in the typical forest distribution area of Guandi Mountain as the research object,the important functional traits such as the fresh-dry ratio,leaf area,chlorophyll and leaves,branches and roots of leaves were analyzed at different ages.(5a,15 a,25a,35 a,45a)and the variation of different altitude gradients(1760m,1820 m,1880m,1940 m,2000m),and the distribution pattern of carbon,nitrogen,phosphorus and their ratios among organs with age and altitude Time and space changes,further analysis of the effects of soil spatial variability,tree age and altitude on various functional traits.The results show:1)With the increase of tree age,leaf area,leaf fresh-to-dry ratio,branch phosphorus content,root organic carbon content and leaf area showed an increasing trend,the maximum values were 20.81mm2,56.06%,1.91 g.kg-1,respectively.532.50 g.kg-1,and the leaf phosphorus content and leaf organic matter content decreased,and the minimum values were 1.48 g.kg-1,530.06 g.kg-1,respectively.With the increase of tree age,leaf area and leaf fresh-to-dry ratio increased,leaf phosphorus and root phosphorus content decreased,leaf organic carbon content decreased,but root organic carbon was up-regulated.There was a significant correlation between tree age and leaf phosphorus content,branch phosphorus content,leaf organic matter content,root organic matter content,leaf fresh-to-dry ratio,average leaf area and leaf area There was a significant positive correlation between tree age and fresh-to-dry ratio,leaf area,root organic carbon content and leaf organic carbon content,and a significant negative correlation with shoot organic carbon content..2)With the increase of altitude,with the increase of altitude,the fresh-to-dry ratio,chlorophyll content,average leaf area,branch organic carbon content and root organic carbon content of leaves increased,and reached the maximum at 2000 m above sea level.,respectively,51.78%,79.08 g.kg-1,18.97mm2,547.26 g.kg-1,521.68 g.kg-1;while the leaf organic carbon content showed a decreasing trend,reaching a minimum at an altitude of 2000 m,525.44 g.kg-1;the phosphorus content in branches,roots and leaves increased first and then decreased,reaching the maximum at 1820 m above sea level,which were 2.16 g.kg-1,1.43 g.kg-1,1.73 g.kg-1;the nitrogen content of leaves,roots and branches reached the maximum value of 14.46 g.kg-1,7.84 g.kg-1,11.48 g.kg-1 at an altitude of 1880 m,which increased first and then decreased.trend.There was a significant positive correlation between altitude,leaf area and total chlorophyll content,and a significant negative correlation with leaf phosphorus content and leaf phosphorus content.There was a significant positive correlation between altitude and leaf area and nitrogen content,and a significant negative correlation with root phosphorus content.3)Correlation analysis between functional traits showed that there was a significant negative correlation between phosphorus content and phosphorus content,root organic carbon content and root nitrogen content,and a significant positive correlation with root phosphorus content,specific leaf area and leaf organic carbon content..There was a significant negative correlation between phosphorus content and root phosphorus content,specific leaf area and leaf organic carbon content,and a significant positive correlation with root organic carbon content and root nitrogen content.There was a significant positive correlation between root phosphorus content,leaf organic carbon content and specific leaf area,and a significant negative correlation with root organic carbon content.There was a significant negative correlation between leaf organic carbon content and root organic carbon content,leaf fresh-to-dry ratio,and a significant positive correlation with leaf area.4)With the increase of tree age,the distribution pattern of carbon,nitrogen and phosphorus content and their ratios among organs showed that phosphorus was relatively distributed in leaves and roots at an early age,and concentrated in branches in adulthood.In the range of 5a-45 a of the study,the nitrogen distribution showed a stable pattern of leaf>branches>roots,which did not change significantly with age.The proportion of organic carbon in the roots increased slightly with age,and the proportion of roots decreased slightly.The distribution of C:N in the three organs of leaf branches is relatively uniform,and does not change significantly with the change of tree age.The distribution of C:P and N:P in the three organs fluctuated greatly with the change of tree age,and all of them reached the minimum distribution ratio in the 35-year-old Picea wilsonii tree species,and reached the largest distribution among the roots.ratio.The distribution ratios of carbon,nitrogen and phosphorus contents at different altitudes and their ratios in different organs of leaf branches showed that C:N was less distributed in leaves,followed by branches,the roots were the most,and the distribution was stable.There will be significant changes as the altitude changes.However,the distribution of C:P and N:P in the three organs fluctuated greatly with the change of tree age,and in the Picea wilsonii tree species at an altitude of 1940 m,the distribution in the leaves reached the maximum,and the distribution in the roots.The ratio reaches a minimum ratio.5)The soil exhibits heterogeneity in both horizontal and vertical spaces: soil nitrogen,phosphorus and organic carbon are plaque-like in space as a whole.The plaque distribution of nitrogen and organic carbon showed a similar pattern in space,that is,the soil nitrogen and organic carbon content in the southern part of the plot were higher,reaching 33 g.kg-1 and 166 g.kg-1,respectively;The plaque of phosphorus content is opposite to the content of nitrogen and organic carbon,reaching the highest value in the northwest and northern regions of the plot,which is higher than 30 g.kg-1.With the increase of altitude,soil carbon content increased,the maximum values were 3.31% and 65.52 g.kg-1,respectively.The soil phosphorus content and nitrogen content increased first and then decreased,and both of them The maximum value was reached at an altitude of 1820 m,and the maximum values were 0.47 g.kg-1 and 4.88 g.kg-1,respectively.According to the comprehensive research,the changes of different indicators of Picea wilsonii,age,and soil indicate that the Picea wilsonii can form survival strategies in different growth stages by changing its physiological and morphological traits and its coordinated distribution among organs.Adaptability to changes in the external environment. |
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