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541.
阐述了在土地处理制革废水过程中污染物的去除机理。其主要方式是物理、化学和生物的去除,并给出在一定土壤状况下去除机理的综合模型。 相似文献
542.
土地资源可持续利用研究 总被引:2,自引:0,他引:2
坚持土地资源的可持续利用对经济发展与社会安定至关重要文章从可持结发展的概念出发介绍了土地资源可持续的含义与评价标准,分析了其实现存在的障碍,进而从认识,管理和科技角度提出了相应的对策。 相似文献
543.
ABSTRACT Reflecting on the 2019 Open Science Meeting of the Global Land Program and on commentaries since, we argue that the time is ripe for the land system science community to fully embrace the thorny issue of land ownership and control. Beyond land governance and institutions, the issue of who actually owns and controls land, and how land holding and rents are distributed across society, is central to the future of sustainability initiatives, biodiversity protection, social justice, climate change mitigation, and long-term food security and sovereignty. By explicitly tracking and visualizing just Who Owns the Earth, the land system science community could provide much-needed data and insights to inform public debate and advance political action in these arenas. 相似文献
544.
Anne Cristina de la Vega-Leinert 《Journal of Land Use Science》2020,15(2-3):172-202
ABSTRACT The Santa Cruz lowlands, east Bolivia, are one of South America’s most dynamic agricultural frontiers. In the Chiquitania, bordering Brazil, San Ignacio de Velasco was in 2017 ranked first nationally in terms of deforestation. There, two deforestation fronts meet with mechanized agriculture expanding from the West and South and cattle ranching from the East. Chiquitano communities are demographically dominant locally but often face land scarcity. Because of their comparatively low impact on forest vegetation, they are not well represented in broad-scale quantitative Land Use/Land Cover (LULC) studies. Based on an empirical, human geographical approach, this paper investigates the transformation of the local indigenous productive matrix, the associated land-use patterns and potential socio-ecological implications. The overall aim is to bear witness to the rapid and profound reconfiguration of traditional livelihoods with their integration in the market economy and to highlight the significance of micro-scale LULC-processes at global scale. 相似文献
545.
A field experiment was carried out to determine the effect of different land use systems such as continuous grass and agricultural crops rotation on the bioavailability of heavy metals in soils contaminated by former excessive sewage sludge application. The results show that Cd and Zn concentrations increased to 2 and 3.5 folds within 3 cuts of grass, respectively. Even 10 years after the end of excessive sewage sludge application the concentration of Cd in winter and summer wheat is 3.4 and 2.5 folds higher than the control, respectively. Zn concentration increased by two folds for both crops. In conclusion, the uptake depends on plant species and the degree of soil contamination. The availability of heavy metals was not changed with time. 相似文献
546.
以实际观测为依据,以七台河地区地质条件为背景,给出该区塌陷变形,诸如不均匀沉降、地面倾斜、曲率变化、移动等力学量的估算。 相似文献
547.
Soil erosion is accelerating in developing countries of Asia, Africa, and Latin America. It has threatened the livelihood
of millions of peasants, for agriculture is their economic mainstay. A probe into the forces causing erosion reveals that
the elite’s resolve to accumulate ever more wealth and to maintain, consolidate, or expand their sociopolitical power and
the necessity of the poor to fulfill their requirements of food, fuelwood, and fodder are the two major factors accelerating
soil erosion. Unless the vast masses of poor people are integrated into the national mainstream through the implementation
of equitable and redistributive development policies, it is impossible to control the accelerating rate of soil erosion and
thus to achieve the objective of sustainable development.
In this article, the phenomenon “soil erosion” is studied with the sol e focus on causation through anthropogenic factors. 相似文献
548.
The ability of Section 404 of the Clean Water Act to act as an effective, efficient, and equitable land-use planning tool
was assessed through a survey of Section 404 permits in Wisconsin. In a six-month period of permitting, the 404 program reduced
wetland losses in the state by 15%. Several factors were examined that may affect permit decisions; these factors are water
dependency, alternatives, project type, wetland type, and public or agency comments. Only the water dependency of the project
had a statistically significant effect on permit decisions, although development projects that were perceived to provide public
good were more likely to be permitted. Environmental impacts of a proposed fill project were not adequately assessed in any
of the permit decisions. Because of the way Section 404 is interpreted and administered by the US Army Corps of Engineers,
increasing net benefits and achieving an equitable distribution of those benefits is difficult. The corps does not perform
any functional evaluations of wetlands nor do they attempt to measure economic value and environmental impacts. In addition,
the 404 review process is, in effect, inaccessible to the public. The de facto interpretations of the Section 404 regulations
and a lack of program funding and trained personnel all contribute to the program's ineffectiveness. 相似文献
549.
550.
塌陷灾害与塌陷工程学 总被引:4,自引:0,他引:4
论述主要由于人类工程活动而引起的塌陷灾害及塌陷工程学。叙述塌陷灾害给城市建设、工程建筑,生态平衡及社会环境等方面造成的严重后果。阐述塌陷工程学的内涵、研究内容、目的及研究方法,以及与岩石力学、结构力学,建筑设计、施工等工程科学和社会学等学科的关系。 相似文献