| The meadow ecosystem in Wugong Mountain was seriously damaged in recent years,and what is not surprisingly is that the grassland degradation phenomenon has been being more serious.However,the stability of shrubland and forest ecosystems under the meadow area is unknown.This study focus on the three vegetation types whole ecosystem(include forest,shrubland and meadow vegetation type)in Jiangxi Wugong Mountain,which based the current research theory of biological chemistry metrology,to reveal the interaction regularities and mechanisms of carbon(C),nitrogen(N),and phosphorus(P)in the three vegetation types of Wugong Mountain.In order to obtain the C,N,P contents and their stoichiometric ratio of vertical distribution in the three different vegetation types of Wugong Mountain,the change pattern of C,N and P in soil and litter at altitude gradient were analyzed.Furthermore,the final evaluation and analysis of the whole ecosystem of Wugong Mountain done in the view of homeostasis of biological chemistry metrology,which provide the basis for the management and sustainable development of Wugong Mountain ecosystem.The research results as bellows:(1)The average contents of C,N and P in litter of Wugong Mountain are 503.47 g/kg,14.86 g/kg,and 1.77 g/kg,respectively.Moreover,the corresponding contents in soil are 68.51 g/kg,5.10 g/kg and 1.97 g/kg,respectively.The results show that it has different regularities of nutrient content in soil and litter of three different vegetation types;significant differences for the contents of C,N and P in the soil and litter of forest,shrubland and meadow vegetation types and more factors are need to be considered to get further study of its spatial distribution pattern.Furthermore,the nutrient of litter and soil mainly affected by its degree of decomposition and the regional environment,respectively.Moreover,Phosphorus is relatively stable relative to Carbon and Nitrogen.It is also easily to see that the phosphorus deficiency phenomenon in soil and litter of this research area is better than that in other areas of China.(2)The average C/N,C/P,N/P in the litter of three different vegetation types in Wugong Mountain are 35.08,303.37,8.65,respectively.It has the same variation regularity of ratio of C/N,C/P,N/P in soil and litter of three different vegetation types(i.e.the ratio of C/N,C/P,N/P in soil and litter of three different vegetation types has the same regularity: meadow<forest<shrubland).The stoichiometric characteristics of the litter and soil indicate that the nutrient cycling mainly dominated by N element within this research area.Moreover,the related relationship between soil and litter in this research area may affected by the climate environment.(3)From the point view of homeostasis,the homeostasis indexes of different elements are different.It has the homeostasis for the C,P elements in meadow vegetation(H>1).It's more stable for that the homeostasis of C element compared with P element.However,N element does not has the homeostasis.The C,N,P element do not has the homeostasis in shrubland vegetation and it has been experiencing a very unstable period.The P element does not have the homeostasis in forest ecosystem.However,it has the homeostasis for C and N element and that of N element is more stable that of C element.It is not so different to conclude that it has been experiencing the stable period in the research area,the P element has the worst homeostasis compared with C and P element(N element has the best homeostasis),the degradation problem in Wugong Mountain meadow area mainly dominated by N element and human disturbance. |
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