Response of soil ecological stoichiometric characteristics to grazing intensity in Stipa kirschnii grassland

Ecochemometrics aims to study the balance of various elements in an ecosystem, which is of great significance to the exploration of soil organic carbon(C), total nitrogen(N), total phosphorus(P) element cycle, and soil nutrient limitation. In order to understand the soil ecological stoichiometric characteristics of Stipa kirschnii grassland, this paper took Stipa kirschnii grassland in Inner Mongolia as the research object, and conducted sampling analysis in pastures with different grazing intensities. The results showed that with the increase of grazing intensity, the content of C and P first decreased and then increased, and the content of N first increased and then decreased. Soil C/N first decreased and then increased, C/P gradually increased, and N/P first increased and then decreased. With the increase of grazing intensity, the correlation between C/N and organic carbon increased gradually, while the correlation between C/N and total nitrogen decreased gradually. The C/P of light pastoral area was enhanced by organic carbon. N/P in the middle pastoral area was enhanced by total nitrogen. The main limiting factor of C/N is organic carbon content, while the main limiting factor of C/P and N/P is total phosphorus content. Different grazing intensities will affect the relationship between soil stoichiometric ratio and other substances, and also change the strength of each limiting factor of soil stoichiometric ratio.