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1.
IMPACTS OF VISITORS ON SOIL AND VEGETATION OF THE RECREATIONAL AREA “NACIMIENTO DEL RÍO MUNDO” (CASTILLA-LA MANCHA, SPAIN) 总被引:1,自引:0,他引:1
Andrés-Abellán M Del Alamo JB Landete-Castillejos T López-Serrano FR García-Morote FA Del Cerro-Barja A 《Environmental monitoring and assessment》2005,101(1-3):55-67
This study examines the effects of recreational use on the soil and vegetation at a site of ecological importance (Nacimiento del Río Mundo, Albacete, Spain). The most visited sites showed increased soil compaction of approximately 50%, bare ground increase to 61 ± 10% and a decrease in richness (from 25 ± 2 to 15 ± 2 species), diversity (from 4.0 ± 0.1 to 2.7 ± 0.4) and stratification of plant species (from 80 ± 11 to 21 ± 4%). The most visited sites had 90% less plant species as compared to the least visited. Intense use was associated with the presence of nitrophilous plant and vegetal species with a morphology adapted to heavy trampling. The recreational areas showed a distribution pattern of impact radiating outwards from the most used and degraded point. At the most visited point, Los Chorros (the spring of the river), the impact radiated outwards for about 20 m. A pilot experiment examining the effects of one-year restriction to visitors for access to a formerly impacted area showed a plant cover increase by anthropic and not by native species of 57 percent units. 相似文献
2.
Lee TM 《Environmental monitoring and assessment》2005,111(1-3):307-323
This study analyzes the results of the first 5 years of long-term environmental monitoring of the dynamics of coastal vegetation
communities in southwestern Taiwan. Seven permanent plots were established in major vegetation communities, including grassland,
windbreak forest, and secondary succession forest. Results showed that species richness decreased yearly in grasslands but
fluctuated moderately in the forest plots. A Jaccard similarity coefficient was used to evaluate the similarities of species
composition between different monitoring years. Species composition changed rapidly in grassland sites, with the similarity
coefficient dropping from 82 to 29% in 5 years. The similarity coefficient of vegetation in the compositehardwood forest dropped
from 80 to 50%, indicating that at least half the species were the same as those in the beginning and that the composition
of forest communities was more stable than that of grassland communities. Dominant species in the forest community changed
gradually during the monitoring period. The original planting of Casuarina equisetifolia in windbreak forests decreased year by year in most of the plots, while Cerbera manghas and Ficus microcarpa became the dominant species. The trend of replacement of dominant species indicates that most of the vegetation communities
are still in successional stages. 相似文献