Carbon (C), nitrogen (N) and phosphorus (P) are the most important three elements in an ecosystem. The stoichiometry of nutrients reflects their circulation and distribution.

Researchers form the Xinjiang Institute of Ecology and Geography (XIEG) of the Chinese Academy of Sciences (CAS) investigated the ecological stoichiometry of plants at different elevations in the Altun Mountain Nature Reserve, from alpine desert ecosystem to alpine grassland ecosystem.

The study was published in Catena.

They found that plant C, N, P and soil C, N were linearly correlated with elevation gradient, and so did the C: N, C: P of plants and C: P, N: P of soil. Plant C and N were mainly affected by soil C and N concentration, but there was no significant correlation between plant P and soil nutrient concentration.

Soil moisture content and soil pH can affect soil nutrients. Soil moisture content increased with elevation, facilitating nutrient mineralization and availability to the ecosystem. This would increase species diversity and promote plant community assembly and succession from alpine desert ecosystem to alpine grassland ecosystem.

The results of stoichiometric analysis of plant and soil with different vegetation types at 3,000m to 4,000m in the Altun Mountains showed that the nutrient distribution of alpine grassland and alpine desert ecosystems differed greatly at different altitudes.

The C concentration of plant community was higher in low altitude alpine desert ecosystem while the N and P concentration of plant community was higher in high altitude alpine grassland ecosystem. The consistency of soil C and N changes and the stability of soil P led to the same change of soil C: P and N: P in different soil layers and altitudes.

The stoichiometric characteristics of plant communities vary with species composition and ecological strategies.