Impacts of Overgrazing and Reclamation on Soil Resources in Rangeland Ecosystems in Huailai Basin, Hebei, China

摘要

The soil constituents and relations between the variation of soil resources and plant communities in three adjacent sites representing the overgrazing, reclamation and comparatively undisturbed communities respectively were quantified and examined instudy area in Huailai Basin, Hebei Province, China. There have been significantly greater constituent of C, N, P in the soils of shrubland site. C_(org), N_(total), N_(avail) and P_(avail) were between 1. 18 and 3. 90 times more concentrated in the soilsof shrubland site in comparison with the other two sites. Although the P_(total) concentration was lower in shrubland soils than in overgrazed rangeland soils, the P_(avail) concentration, however, was significantly greater in the soils of shrubland site, and increased by 59.1% and even 289. 6% in the soils of shrubland site comparing to those in the soils of range-land and millet field sites. Among the three sites, CV exceeding 40% were found for SO_4 , Cl, and F ion. The CV of organic carbon also exceeded 40 % but only in the soils of millet field site. The highest CV were found for F, SO_4 ion in the soils of shrubland and overgrazed rangeland sites, while for Cl and SO_4 ion in those of millet field site. The results also showed that the introductions of shrubs are of vital importance for the accumulation of soil nutrients and maintenance of soil fertilities, and also for the restoration and reconstruction of desertified ecosystems.