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51.
国际环境制度对能源安全战略的重大影响 总被引:1,自引:0,他引:1
刘东民 《中国人口.资源与环境》2003,13(3):44-47
能源安全一直是国际政治和经济领域的重大问题。在追求可持续发展和全球化不断推进的2l世纪,国际环境制度的逐步形成为能源安全赋予了新的涵义,生态安全已经成为能源安全的重要组成部分。以保障能源供应为主要出发点的传统能源安全观逐渐向着涵盖能源供应、经济竞争力和环境质量三大要素的“综合能源安全观”的方向发展。 相似文献
52.
殷世林 《防灾减灾工程学报》1997,(2)
根据对南黄海6.1级地震前,苏州地区1995年9月~1996年10月以地下水动态、地下水化学为主的前兆异常的分析,预报了这次地震,并对其进行了检验及原因分析 相似文献
53.
This research considers the question of changing environmental values within the leadership of firms responsible for the management of pollution as an unwanted byproduct. Information was obtained from a pair of surveys mailed to the chief executive officers (CEOs) of the 50 largest firms listed within the mining and manufacturing directories of Colorado, Montana, Utah, and Wyoming in 1976 and again in 1986. The authors found that industry CEOs were more supportive of environmental concerns in 1986 than 1976, suggesting that ecological values have become institutionalized to some extent. Yet, there is little indication that this attitudinal shift in environmental concern among CEOs has been accompanied by a willingness to spend a larger proportion of the company budget on pollution control or to improve working relationships with federal regulatory officials. 相似文献
54.
The Brahmaputra changes its course and pattern along with its current flow very frequently especially in its upper stretches and this has a strong bearing on its hydrobiology. The hydro-geological pattern of the Brahmaputra has resulted in a possible zonation of the river into five major types of fish habitat. Altogether 167 fish species have been recorded from the upper Brahmaputra of which about 30 percent may be considered as ornamental varieties. Again, according to their seasonal availability, the fish fauna has been grouped into four principal categories. Among all the hydrological factors, flood impulse is probably the strongest factor that regulates other limnological conditions and faunal distribution. Usually, there are three or four high floods between May and October and fish migration is intimately related to this flood regime. During the dry season fishing is mostly restricted to near the confluents of tributaries or channels and also at river meanders. However, large-scale felling of trees in the catchment areas and construction of embankments along the river banks have altered the riverine ecosystem drastically, as a result of which, the river has become heavily silted and the connecting channels of the floodplain lakes are also dammed. Consequently, fishes and other megafauna are deprived of adequate water cover, food supply and breeding grounds. An ecohydrological approach has been advocated for habitat restoration. 相似文献
55.
煤矿开采对地下水流场影响的数值模拟——以神府矿区大柳塔井田为例 总被引:7,自引:0,他引:7
煤矿开采过程中的矿坑排水对地下水流场和地下水资源利用具有强烈影响.本文通过建立平面二维地下水渗流模型,模拟煤矿开采后地下水流场的变化.模型识别校验后,对煤矿开采后地下水流场的变化趋势进行了预测.预测结果表明,随着采煤范围扩大,矿坑排水量增加,地下水循环途径被改变,充水含水层被疏干,导致泉水断流. 相似文献
56.
Vulnerability of land systems to fire: Interactions among humans,climate, the atmosphere,and ecosystems 总被引:3,自引:0,他引:3
Sandra Lavorel Mike D. Flannigan Eric F. Lambin Mary C. Scholes 《Mitigation and Adaptation Strategies for Global Change》2007,12(1):33-53
Fires are critical elements in the Earth System, linking climate, humans, and vegetation. With 200–500 Mha burnt annually,
fire disturbs a greater area over a wider variety of biomes than any other natural disturbance. Fire ignition, propagation,
and impacts depend on the interactions among climate, vegetation structure, and land use on local to regional scales. Therefore,
fires and their effects on terrestrial ecosystems are highly sensitive to global change. Fires can cause dramatic changes
in the structure and functioning of ecosystems. They have significant impacts on the atmosphere and biogeochemical cycles.
By contributing significantly to greenhouse gas (e.g., with the release of 1.7–4.1 Pg of carbon per year) and aerosol emissions,
and modifying surface properties, they affect not only vegetation but also climate. Fires also modify the provision of a variety
of ecosystem services such as carbon sequestration, soil fertility, grazing value, biodiversity, and tourism, and can hence
trigger land use change. Fires must therefore be included in global and regional assessments of vulnerability to global change.
Fundamental understanding of vulnerability of land systems to fire is required to advise management and policy. Assessing
regional vulnerabilities resulting from biophysical and human consequences of changed fire regimes under global change scenarios
requires an integrated approach. Here we present a generic conceptual framework for such integrated, multidisciplinary studies.
The framework is structured around three interacting (partially nested) subsystems whose contribute to vulnerability. The
first subsystem describes the controls on fire regimes (exposure). A first feedback subsystem links fire regimes to atmospheric
and climate dynamics within the Earth System (sensitivity), while the second feedback subsystem links changes in fire regimes
to changes in the provision of ecological services and to their consequences for human systems (adaptability). We then briefly
illustrate how the framework can be applied to two regional cases with contrasting ecological and human context: boreal forests
of northern America and African savannahs. 相似文献
57.
我国部分地方规定了水污染物排放许可证制度,由于此类法律文件法律效力的低层级性,制约着水污染防治的司法与执法实践。提高设定该制度法律文件效力位阶,不仅可以解决调整该制度法制不统一状况,而且为其进行法律规制提供了直接、具体的法律依据。对促使排污主体科学、合理排污将起到积极作用。 相似文献
58.
Land Cover and Use Changes in Relation to the Institutional Framework and Tenure of Land and Resources in Eastern Tanzania Miombo Woodlands 总被引:3,自引:0,他引:3
E.?J.?Luoga E.?T.?F.?WitkowskiEmail author K.?Balkwill 《Environment, Development and Sustainability》2005,7(1):71-93
In Tanzania, well-defined land tenure and resource protection apply in forest reserves which account for 30% of forested land, while the remaining 70% (mostly miombo woodlands) are village and general lands with very limited protection. The aim of this study was to determine local peoples ownership rights, knowledge and institutional capacity for sustainable management of resources in forest reserves and general lands. Data were collected using participatory rural appraisal, structured and semi-structured interviews, as well as aerial photographs and landsat images. In general lands, woodlands declined by 50% between 1964 and 1996, bushlands and croplands increased by 599%, and settlements and homegardens increased by 277%. These land use and vegetation structure changes are attributed to harvesting for charcoal production and shifting cultivation. The continued decline in aerial woodland cover in the general lands suggests that common property regimes do not function in the area. Local institutional capacities are weak in enforcing control mechanisms to check the overuse of resources, which tends to approximate open access conditions. The issues of land tenure and village empowerment are not only institutional, but also political in nature. Government institutions should provide and motivate for an enabling environment, including acknowledgement of traditional knowledge, well-defined property rights and operational village by-laws. In order to ensure equity and sustainable development of natural resources, the paradigm shift in management is important whereby communal goods are to be managed for the benefit of the local society. 相似文献
59.
Legitimizing Fluvial Ecosystems as Users of Water: An Overview 总被引:6,自引:0,他引:6
Naiman RJ Bunn SE Nilsson C Petts GE Pinay G Thompson LC 《Environmental management》2002,30(4):455-467
We suggest that fluvial ecosystems are legitimate users of water and that there are basic ecological principles guiding the
maintenance of long-term ecological vitality. This article articulates some fundamental relationships between physical and
ecological processes, presents basic principles for maintaining the vitality of fluvial ecosystems, identifies several major
scientific challenges and opportunities for effective implementation of the basic ecological principles, and acts as an introduction
to three specific articles to follow on biodiversity, biogeochemistry, and riparian communities. All the objectives, by necessity,
link climate, land, and fresh water. The basic principles proposed are: (1) the natural flow regime shapes the evolution of
aquatic biota and ecological processes, (2) every river has a characteristic flow regime and an associated biotic community,
and (3) aquatic ecosystems are topographically unique in occupying the lowest position in the landscape, thereby integrating
catchment-scale processes. Scientific challenges for the immediate future relate to quantifying cumulative effects, linking
multidisciplinary knowledge and models, and formulating effective monitoring and assessment procedures. Additionally, forecasting
the ecological consequences of changing water regimes is a fundamental challenge for science, especially as environmental
issues related to fresh waters escalate in the next two to three decades. 相似文献
60.
Undamming Rivers: A Review of the Ecological Impacts of Dam Removal 总被引:26,自引:4,他引:22
Bednarek AT 《Environmental management》2001,27(6):803-814
Dam removal continues to garner attention as a potential river restoration tool. The increasing possibility of dam removal
through the FERC relicensing process, as well as through federal and state agency actions, makes a critical examination of
the ecological benefits and costs essential. This paper reviews the possible ecological impacts of dam removal using various
case studies.
Restoration of an unregulated flow regime has resulted in increased biotic diversity through the enhancement of preferred
spawning grounds or other habitat. By returning riverine conditions and sediment transport to formerly impounded areas, riffle/pool
sequences, gravel, and cobble have reappeared, along with increases in biotic diversity. Fish passage has been another benefit
of dam removal. However, the disappearance of the reservoir may also affect certain publicly desirable fisheries.
Short-term ecological impacts of dam removal include an increased sediment load that may cause suffocation and abrasion to
various biota and habitats. However, several recorded dam removals have suggested that the increased sediment load caused
by removal should be a short-term effect. Preremoval studies for contaminated sediment may be effective at controlling toxic
release problems.
Although monitoring and dam removal studies are limited, a continued examination of the possible ecological impacts is important
for quantifying the resistance and resilience of aquatic ecosystems. Dam removal, although controversial, is an important
alternative for river restoration. 相似文献