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871.
西安地裂缝与地面沉降灾害经济损失评估 总被引:1,自引:1,他引:0
为了深入分析西安地裂缝与地面沉降灾害致灾特点及定量评价其经济损失,在中国地质调查局于2004-2006年开展的西安地区地裂缝与地面沉降调查所取得的成果资料基础上,通过综合分析研究得出,西安地裂缝与地面沉降的致灾特点具有直接性、三维破坏性、三维空间有限性、渐进性和持久性。采用终值法、影子工程法、统计推断法、重置成本法、建造成本或工程费用法、灾情对比法、间接损失与直接损失比例法和权重分解法评价得出地裂缝与地面沉降灾害在1976-2006年造成经济损失为117亿元,其中直接损失71亿元,间接损失46亿元。 相似文献
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上海地下水环境容量评价及在地面沉降控制中的应用 总被引:1,自引:1,他引:0
在分析地下水水环境容量内涵及地下水资源开发利用产生的环境效应基础上,探讨了地下水环境容量的概念,认为地下水环境容量是用来表征一定目标约束下,地下水系统对自然或人类活动影响所能承受能力的最大阙值,并以上海市为例,采用地下水临界水位、地面沉降量、地下水质作为评价指标对地下水环境容量进行了评价,并将其应用于上海市地面沉降防治工作中,剖析了地下水资源管理和地面沉降控制的工作机制。升,第四承压含水层向弹性变形态势转变,土体表现为微量回弹。 相似文献
874.
Fan Wei Mei Han Guangxuan Han Min Wang Lixin Tian Jiqian Zhu Xianglun Kong 《海洋学报(英文版)》2022,41(9):192-204
Coastal wetlands are located in the ecotone of interaction between the land surface and sea, and anthropogenic activities extensively interfere with these wetlands through the reclamation of large tidal wetlands and destruction of the function of the ecosystems. In this study, we investigated the dynamic evolutionary characteristics of the Bohai Rim coastal area over the past 40 years using the Modified Normalized Difference Water Index, the fractal dimension, object-oriented classification, the land-use transfer trajectory, and regression analysis. Additionally, we quantified and monitored the evolution of reclamation and analyzed the correlation between reclamation and coastal wetlands based on 99 Landsat-2, -5, and -8 images (at 60 m and 30 m spatial resolution) over the period 1980–2019. The results are as follows. (1) The coastline of the Bohai Rim increased by 1 631.2 km from 1980 to 2019 with a zigzag variation. The artificial coastline increased by 2 946.1 km, whereas the natural coastline decreased by 90%. (2) The area of man-made wetlands increased by 3 736.9 km2, the area of construction land increased by 1 008.4 km2, and the natural wetland area decreased by 66%. The decrease of tidal flats is the main contributor to the decrease of natural wetland area (takes account for 91.1%). Coastal areas are affected by intense human disturbance, which was taken place across a large area of tidal flats and caused the landscape to fragment and be more heterogeneous. The coastal zone development activities were primarily concentrated in the southern Laizhou Bay, the Yellow River Delta, the Bohai Bay, the northern Liaodong Bay, and the Pulandian Bay. The solidified shorelines and increase in sea level have resulted in intertidal wetlands decreasing and impaired wetland ecology. (3) There is a good agreement between reclamation and the size of the coastal wetlands. Both land reclamation and the reduction in coastal wetland areas are significantly related to the population size, fishery output value, and urbanization rate. In summary, human activities, such as the construction of aquaculture ponds and salt pans, industrialization, and urbanization, are the primary forces that influence the environmental changes in the coastal region. This study is beneficial for establishing and improving the systems for the rational development and utilization of natural resources, and provides theoretical references for restoring wetland ecology and managing future reclamation activities in other coastal zone-related areas. 相似文献
875.
Journal of Geographical Sciences - The dramatic land use changes that occur in rapidly urbanized areas are important inducement to changes in the eco-environmental quality. Investigating urban land... 相似文献
876.
ZHOU Ping WEN An-bang YAN Dong-chun SHI Zhong-lin GUO Jin JU Zhan-sheng ZHANG Yi-lan 《山地科学学报》2014,11(2):526-534
Soil erosion becomes a serious environmental problem in the world, especially in western China. An effective management practice called the Grain for Green Program (GGP), which was launched in 1999, aims to reduce soil and water loss and alleviate the ecological environment problem in western China. Two typical counties in western China, the Zhongxian (in Chongqing Municipality) and Ansai (in Shaanxi Province) were chosen to evaluate the dynamic changes of land use and agricultural production structure before and after the implementation of the Program in this paper. The results showed that the cultivated land area was reduced by 7.08% from 1989 to 2003. The cultivated land per person was decreased by 8.42% during 1999-2003. Moreover, the stability index of the secondary sector of the economy was increased from 0.91 in the period 1990-1999 to 0.94 in the following ten years. In addition, the stability index of tertiary economic sector increased from 0.88 to 0.92 in Zhongxian county. Meanwhile, the cultivated land area was reduced by 15.48% from 1990 to 1999. The soil erosion modulus was decreased by 33.33% from 1999 to 2006. Also, the stability index of secondary and tertiary economic sectors was 0.86 in the period 1998-2002. However, it decreased by 77% during 2002 to 2007 in Ansai County. These results imply that the Grain for Green Program had different impact on the two regions. Several effective strategies of soil and water conservation have been carried out to ameliorate the sustainable development of ecological environment and economy in these two counties of western China. 相似文献
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