Effects of enclosure on storage and allocation of carbon and nutrient elements in Seriphidium transiliense population

The effects of the enclosure on the resource allocation pattern and ecological strategy of Seriphidium transiliense population was investigated. The content, storage and allocation pattern of biomass, carbon and nutrient elements in the sagebrush desert grassland were analyzed on September and October, 2009 and 2010. The results showed that the P content of root, the N content of reproductive shoot, the Ca content of root crown and vegetative shoot in enclosure of moderate degraded plot were significantly higher than those of outside plots (P0.05). The storage of N, P, K significantly increased after enclosure (P0.05). The storage of C, the biomass of reproductive shoot and vegetative shoot increased with the decreasing of degraded intensity, and the values increased more in enclosure of moderate degraded plot. The proportion of N, K of reproductive shoot, the proportion of Ca, Mg and C of vegetative shoot, the ratios of N and C of root crown all showed an increasing trend after enclosure. The ratios of N and C of reproductive shoot in enclosure of moderate degraded plot were significantly higher than those of outside plots (P0.05). The present results suggested that the supply capacity of nutrition of the soil, the resource allocation to vegetative shoot and reproductive shoot all increased in the sagebrush desert grassland after enclosure. The improvement of soil and these performances of S.transiliense population were beneficial to its ecological restoration.