| 其他摘要 | Shenfu-Dongsheng mine area is located in the Mu Us Desert and the Loess Plateau
transition zone of the northwest area of desertification, its ecological environment is fragile,
accompanied by serious erosion. The mining based mainly on open-pit, which brint about
serious damage to its original topography, vegetation landscape, restricted the sustainable
socio-economic development of the mine.
In this study, two years (1990 and 2010) TM images of Zhungeer region were taken as
the data source, based on the landscape ecology theory and landscape pattern analysis
method. The dynamic characteristics of landscape structure, landscape patterns and
landscape vulnerability in the Zhungger mine were analyzed. Combined with the
experimental data of heavy metals in soils, we studied ecological pollution of heavy metals
in mine risk, providing a theoretical basis for the future management and protection of
ecological environment of mining area, the rational allocation of the landscape pattern and
sustained and effective utilization of mine resources.The results showed that:
(1) During the 20 years, the landscape pattern of every townships in Zhungeer
plaque has undergone significant changes in both landscape and patch level, among the
landscape heterogeneity deteriorated, landscape dominance reduced, and landscape
diversity decreased;
(2) During the 20 years, building land area of the three regions was increased; it
significant affected the changes of landscape structure. The area of vegetation cover in the
study area had an increasing trend. However, the landscape was more dispersed and
irregular. The mining area exploitation was the dominate factor to effect the changes of
landscape pattern, such as enlarging the building area, destroying the farmland, and
reducing the cultivated land area. Furthermore, although the woodland and grass-shrub land area were increased, its landscape pattern was more broken, and its ecosystem was
more unstable.
(3)Fragmentation (including patch density and edge density) and separation index
combines well reflect the landscape of information and close ties between the fragile
landscape elements, in Zhungeer County area, landscape fragmentation caused by human
activities and the degree of separation of the vulnerability landscape elements become the
decisive factor. In 20 years as the population, social and economic development of human
activities on natural resources, resource development and regional high-intensity, resulting
in the area of human activity on the landscape elements violent interference. During the 20
years, the ecological vulnerability of Zhungeer’s southern region changed biggest, while
the ecological vulnerability of the total area was increased, indicating that its landscape
elements were lesser stable and more sensitive to outside interference.
(4)Heavy metal content of four mines was quite different, while the content of Sun
Jiahao and He Jiata colliery was significantly higher than that of Zhao Jialiang and Liu
Daogou mine. Multi-affected wind and other factors, the presence of elements in each
sample point had some regularity azimuth (ES> W> N), showed significant enrichment
accumulation trend. On the vertical profiles in the soil and lateral distance, each of heavy
metals had shown a decreasing trend, with some volatility, changed in the magnitude of
differences.
(5) Single factor pollution index and Nemerow pollution index results were basically
consistent, the surrounding farmland soils mines were subject to Cd, Cu, Zn, Pb polluted to
varying degrees. Where Cd pollution was the most serious, moreover 71.4% and 6.9% of
the sampling points and integrated pollution reached alarming levels. The farmland heavy
metals pollution of Sun Jiahao and Zhao Jialiang mine were significantly greater than that
of He Jiata and Liu Daogou mine.
(6) The range of comprehensive potential ecological risk factor of soil heavy metal
pollution surrounding the four mines were between 14.65 ~ 241.96 with an average of
24.70, been at the low level of risk, but the moderate risk had reached the maximum extent.
Sun Jiahao mine ecological risk was greater than the He Jiata colliery, RI values were
45.03 and 20.04, Zhao Jialiang colliery’s ecological risk was greater than Liudaogou
colliery’s, RI values were 18.74 and 14.97; the largest degree of ecological risk influence of individual elements was Cd element, and the minimum was Zn element, and Cd made
the biggest contribution to the RI values, was the most important mining soil environment
pollution elements and potential risks elements.Cd element is the most important mining
pollution and potential risks element in the four soil environment. The soil heavy metals
surrounding the four mines were some homology with obvious characteristics of soil heavy
metals contamination.
Key words: Shenfu Dongsheng mine; landscape pattern; eco-environment vulnerability;
ecological risk assessment |
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