干旱区生态环境知识资源中心

Soil and vegetation are good indicators of environmental changes. The examined area is semi-arid, extreme dry where open grassland is the typical vegetation. Soils are dry and sandy with vegetation types showing xerotherm characteristics and dominated by endemic species. Urbanization caused growth of nitrate content in the degraded, shallow, sandy soils, while the physiognomy or the vegetation remained the same with sonic changes in the species composition: the amount of weeds and species resistant to disturbance has increased and the Cynodon dactylon has become dominant on grasslands. Among values measured in the upper soil, humus and lime content are higher in quadrates dominated by Festuca pseudovaginata and, on the contrary, K(2)O, P(2)O(5) and total-N show higher values on the area of Festuca vaginata. A new species, Festuca pseudovaginata has appeared in an environment influenced by humans at a higher extent.