Leaf Stoichiometry And It's Response Of Elevation For Picea Asperata Mast. Regeneration Seedling

In the forest ecosystem,the natural regeneration and growth process of forest seedlings is very important.It is a natural biological process for the reproduction of forest resources in the ecosystem dynamics,which has far-reaching influence on the structure and biodiversity of forest communities in the future.The changes in chemical composition of uatural update seedlings,especially C,N,P,are not only the key indicators of community structure and function,but also an ecological adaptation to the environment.Therefore,it is very important to study the ecological and chemical characteristics of seedling leaves and their response to altitude gradient in the process of natural forest regeneration.This information is important for exploring the ecological adaptation mechanism of C,N,P chemical metering of forest regeneration seedlings and the redistribution pattern of elements in ecosystems,which is important for understanding the mechanism of species renewal and the reconstruction and management of forest ecosystems.In this study,the spruce of typical dominant tree species of secondary temperate coniferous forest in North China was studied.In this study,plots were set up at different altitudes.First,The chemical metrological characteristics of the seedlings were studied at different developmental stages(different seedling ages)at the same altitude.Second,the seasonal dynamics of the petrological characteristics of the seedlings at different developmental stages(different seedling ages)at the same altitude were studied in the natural regeneration process of Picea asperata.Third,this paper studied the difference of chemical metrological characteristics and the relationship between leaf stoichiometry and soil stoichiometry in different altitude.The relationship between eco-stoichiometry and soil eco-chemical metering and its response to altitude gradient were elucidated.The results were based on the chemical metrological characteristics of the species's own nutrient elements and their response to the environment,revealing the species in the process of natural regeneration Ecological adaptation strategies and updating mechanisms.The conclusions have been proposed as foiiows:(1)The contents of organic carbon,total nitrogen and total phosphorus in the leaves of spruce increased with the increase of seedling age,and the ratio of carbon to nitrogen,ratio of carbon to phosphorus and nitrogen to phosphorus decreased with the increase of seedling age.Leaf nitrogen and phosphorus were significantly positive correlation,indicating that the two elements have a certain coupling.While the leaves of organic carbon and phosphorus was not significant.(2)The content of organic carbon,total nitrogen and total phosphorus in leaves of spruce was the highest in August,followed by May and the smallest in October.Leaf ratio of carbon and nitrogen,carbon and phosphorus ratio,nitrogen and phosphorus ratio in August the lowest.(3)There was a significant positive correlation between phosphorus and soil phosphorus in the leaves of spruce,and there was a significant positive correlation and negative correlation between nitrogen and phosphorus in soil and nitrogen and phosphorus ratio.The total organic carbon,total nitrogen,total phosphorus and stoichiometric ratio of leaf spruce had a certain coupling with the stoichiometric ratio of soil.(4)The content of organic carbon,total nitrogen and total phosphorus in leaves of spruce increased with the increase of altitude.The increase of organic carbon,total nitrogen and total phosphorus increased with the increase of altitude,and the increase rate of the seedlings was small.Leaf phosphorus and phosphorus ratio,nitrogen and phosphorus ratio decreased with the increase in altitude,carbon and nitrogen ratio with the altitude of irregular changes...