Soil stoichiometric characteristics of alpine meadow in northwest Yunnan under different disturbance types

The effects of different disturbances (enclosure + fire, enclosure + fertilization, enclosure, and grazing) on soil nutrients and on the stoichiometric characteristics of soil C, N, P, and K in alpine meadows in Diqing Prefecture, Yunnan Province, were analyzed. The results were as follows: 1) Under the same type of disturbance, the concentrations of soil C, N, P, and K decreased with increasing soil depth. There was a negative correlation between soil C, N, P, and K concentrations and soil depth, which could be well fitted by a linear function. 2) The concentrations of C, N, P, and K were higher in the enclosure + fertilization, and grassland enclosure soil, at a depth of between 0 cm and 30 cm. The concentrations of C and N in the enclosure + fertilization soil were significantly higher than those in the other three types (P < 0.05). The P concentration in the enclosure + fertilization soil was significantly higher than that in the other soils at a depth of between 0 cm and 10 cm. 3) In the 0 − 40 cm soil layer, the concentrations of C, N, P, and K in grazing and enclosure + fire soil were lower than that in the other two disturbances. This result indicated that there was a severe loss of soil nutrients after grazing and fire. 4) The N in the soil of the study area determined the change in chemometrics in the grassland ecosystem. The average value of soil N in our study was 29.34, which was higher than the national average level of N found in alpine plateaus (13.6). The results indicated that the decomposition rate of soil organic matter was high, and soil organic matter was scarce in the study area. Therefore, enclosure + fertilization is an ideal choice for alpine meadow grassland restoration and grazing management.