| The study of geographical distribution and its influencing factors of plant-litter-soil ecosystem chemometrics is one of the hot topics in recent ecological studies.In Ailao mountain national nature reserve in Yunnan thing slope at an altitude of 1500 ~ 3100 m of natural forest vegetation as the research object,in every 100 m elevation gradient set three 20 m × 20 m samples,collected samples within the dominant species in the arbor layer of leaves,fresh litter and 0 ~ 10 cm of topsoil,and indoor determination and analysis of research on forest ecosystem in the leaf litter-soil C,N,P content and the characteristics of the ecological stoichiometry and nutrient of the coupling between different components and ecological stoichiometric ratio on the elevation gradient changes,the following main conclusions:(1)the average values of the contents of C,N and P in leaves,litters,soil and their eco-stoichiometric ratios on the eastern slope of Ailao mountain were 534.79 g/kg,15.55 g/kg,1.15 g/kg,38.61,544.10 and 14.83,respectively.492.11 g/kg,10.53 g/kg,0.57 g/kg,55.30,1174.26,22.01;96.09 g/kg,5.58 g/kg,0.84 g/kg,20.26,137.76,6.90.The average values of the contents of C,N and P in leaves,litters,soil and their eco-stoichiometric ratios were 559.85 g/kg,12.46 g/kg,1.27 g/kg,48.60,532.83 and 11.74,respectively.499.19 g/kg,9.07 g/kg,0.65 g/kg,61.82,911.22,17.54;82.39 g/kg,5.06 g/kg,0.82 g/kg,17.10,119.65,7.24.On the east and west slopes of Ailao mountain,the contents of C and N in different components were all leaf > litter > soil,while the contents of P were leaf > soil > litter.The content difference between leaf and litters was not significant,but significant.The ecostoichiometric ratios of leaves,litters C,N and P in the east and west slopes of ailao mountain were not significantly different from those of soil in the same elevation gradient.The ratios were all litter > leaf > soil.(2)Comparing the above results with the ratios of leaf,litter,soil C,N,P content and their ecological stoichiometry in other regions,it is found that the carbon storage capacity of the forest in Ailao Mountain is strong,and the C content of leaves and litter in the west slope is higher.Dongpo is high.The lack of N elements in plant leaves at high altitudes in the east and west slopes is the main factor limiting plant growth.The loss of plant P in low altitude areas is the main factor limiting plant growth,while the soil N and P contents are higher than the average soil content in China,low altitude areas.The N:P ratio of litter is large,and the effectiveness of soil P element is low,which is the main ecological factor for the degradation of forest in low altitude areas of the mountain.(3)a significant relationship between dongpo blade,litter and soil is mainly manifested in three components between the respective content of C,N,P and its ecological stoichiometric ratio,leaf C content,soil clay content and other components of the ecological characteristics of stoichiometric does not appear significant correlation,only the leaf P content and soil N,P content,leaf C: N ratio and soil N,P content and C: N ratio,leaf N,P content and soil P content and C: P,N: P ratio and the natural water content significantly related or significant correlation.Compared with the eastern slope,the nutrient recycling and utilization in the leaf-litter-soil system in the western slope was close,and the natural water content of soil had a strong effect on the decomposition and leaching of litter-nutrient elements,and the soil clay particles had a strong effect on the absorption and utilization of available soil nutrients by plants.(4)the Ailao mountain things slope leaf and soil C,N,P content and its ecological characteristics of chemical metrology significantly related with altitude gradient change,then the whole different nutrient composition and ecological stoichiometry than dongpo significant correlation with elevation gradient,mainly due to go on the temperature and precipitation changes in elevation gradient correlation is stronger.The content of C,N and P of leaves and litters and their ecological stoichiometric characteristics have basically the same change trend in the elevation gradient,and the difference of C content in the elevation gradient is not obvious.The ratio of N content,C: P and N: P decreases with the elevation rise,while the content of other values changes in the opposite trend.The contents of N and P in the soil of the east and west slopes of Ailao mountain were low,but the contents of N and P in the leaves were high in the high altitude areas.The natural water content of soil on both east and west sides increases with the elevation.The natural water content of soil in the east slope area increases slowly,while that in the high altitude area increases rapidly.The natural water content of soil in the west slope increases steadily on the elevation gradient. |
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