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761.
This paper provides an overview of the environmental impact of mining on viable future land use and underlines the imperative of improved environmental management and closure planning. It argues that pollution prevention, through planning for closure, can lead to cost-effective strategies for sustainable minerals development and viable future land use. This seems to be most true for greenfield sites since, generally, the earlier closure planning and pollution prevention is built into a project, the more cost-effective and environmentally benign closure will be. Further, for greenfield sites, pollution prevention techniques can be employed from the outset, at the stages of exploration and mine development, and then monitored and improved through the operation stage to closure, and can be kept in place to manage future land use.
The paper discusses how global changes in the industry, following the liberalisation of investment regimes, and mergers and strategic alliances between key firms, has, by virtue of the diffusion of new technology, led to further opportunities to prevent pollution and optimise future land use through planning for closure from the outset. The objectives and components of closure plans are also reviewed as the paper draws on case studies to highlight some of the possible constraints and challenges to pollution prevention that may be faced at the level of both public policy and corporate strategy. The article concludes by suggesting a forward-looking approach to integrated environmental management and viable future land-use planning based on a dynamic model for environmental management.  相似文献   
762.
TIM: Assessing the sustainability of agricultural land management   总被引:1,自引:0,他引:1  
TIM (Threat Identification Model) is a framework for the ex ante assessment of agricultural land management sustainability at the land unit scale that identifies sources of unsustainability within agricultural land management systems. The model explicitly links defined hazards to land productivity and environmental integrity, land resource data and information, and land management practice options using expert and local knowledge on land management and its potential effects. The model was tested in the Crystal Creek Subcatchment, a narrow coastal strip of land situated in north Queensland, Australia. This area was chosen due to the expansion of the sugar industry onto increasingly marginal land in the area, which represents a threat to sustainable land use and a requirement for careful land-use planning and land management.TIM may be used in a relational database as a stand alone decision support system for land-management planning. Its usefulness in land-use planning is greatest when it is linked to a Geographic Information System (GIS) as shown in this paper. GIS allows TIM outputs, such as constraints to agriculture and site-specific best-management practices, to be identified in a spatially explicit manner.The main advantages of TIM are that it can be done ex ante, it removes the need to define sustainability assessment criteria and indicators, it utilises current understanding of the causes and effects of land degradation and how different land-management practices influence these, and links this knowledge to definite land-management options.  相似文献   
763.
ABSTRACT: Severe drought is a recurring problem for the United States, as illustrated by widespread economic, social, and environmental impacts. Recent drought episodes and the widespread drought conditions in 1996, 1998, and 1999 emphasized this vulnerability and the need for a more proactive, risk management approach to drought management that would place greater emphasis on preparedness planning and mitigation actions. Drought planning has become a principal tool of states and other levels of government to improve their response to droughts. For example, since 1982, the number of states with drought plans has increased from 3 to 29. Many local governments have also adopted drought or water shortage plans. Unfortunately, most state drought plans were established during the 1980s and early 1990s and emphasize emergency response or crisis management rather than risk management. This paper presents a substantive revision of a 10‐step drought planning process that has been applied widely in the United States and elsewhere. The revised planning process places more weight on risk assessment and the development and implementation of mitigation actions and programs. The goal of this paper is to encourage states to adopt this planning process in the revision of existing drought plans or, for states without plans, in the development of new plans.  相似文献   
764.
土地利用规划生态环境影响区域差异研究   总被引:5,自引:1,他引:4  
应用生态系统服务价值计算方法,在结合区域实际确定单位面积土地生态系统服务价值的基础上,分析了广西崇左市各县市(区)土地利用总体规划实施前后生态服务价值变化,从而评价规划实施所产生的生态环境影响.结果显示:崇左市及部分县市(区)土地利用的生态系统服务价值呈上升趋势,最大增幅达1.33%;所选取的8种生态功能变化各异,其中气体管理功能增幅最大,达1.03%.表明崇左市各县市(区)在规划实施过程中已取得一定的生态环境建设成果,生态环境质量开始向良性发展,但仍需加强生态建设的力度,进一步提升土地生态系统服务功能.为此在规划修编的过程中,应当结合生态建设的要求,更加关注对生态与环境用地的合理调控.   相似文献   
765.
耕地总量动态平衡的实施途径构想   总被引:14,自引:3,他引:11  
本文从数量、质量、空间、时间等六方面系统探讨了耕地总量动态平衡的内涵与外延,对其核心数量平衡与质量平衡进行了相关分析,在此基础上初步提出了耕地总量动态平衡在土地利用总体规划中的实现思路,分析了我国耕地总量动态平衡实现的初步设想。  相似文献   
766.
ABSTRACT: Appearances matter for managing riparian landscapes because the appearance of landscapes affects public willingness to accept plans and designs that improve ecological quality. Riparian landscape design and planning should respect and strategically incorporate characteristics that the public values and expects to see. Such design can be quite novel in its ecological effects, but it also should be sufficiently familiar in appearance to correspond with cultural values. This paper describes some influential cultural values for riparian landscapes and demonstrates how attention to such values supports public acceptance of ecologically innovative design in rural and urban watersheds.  相似文献   
767.
ABSTRACT: Channel instability and aquatic ecosystem degradation have been linked to watershed imperviousness in humid regions of the U.S. In an effort to provide a more process‐based linkage between observed thresholds of aquatic ecosystem degradation and urbanization, standard single event approaches (U.S. Geological Survey Flood Regression Equations and rational) and continuous hydrologic models (HSPF and CASC2D) were used to examine potential changes in flow regime associated with varying levels of watershed imperviousness. The predicted changes in flow parameters were then interpreted in concert with risk‐based models of channel form and instability. Although low levels of imperviousness (10 to 20 percent) clearly have the potential to destabilize streams, changes in discharge, and thus stream power, associated with increased impervious area are highly variable and dependent upon watershed‐specific conditions. In addition to the storage characteristics of the pre‐development watershed, the magnitude of change is sensitive to the connectivity and conveyance of impervious areas as well as the specific characteristics of the receiving channels. Different stream types are likely to exhibit varying degrees and types of instability, depending on entrenchment, relative erodibility of bed and banks, riparian condition, mode of sediment transport (bedload versus suspended load), and proximity to geomorphic thresholds. Nonetheless, simple risk‐based analyses of the potential impacts of land use change on aquatic ecosystems have the potential to redirect and improve the effectiveness of watershed management strategies by facilitating the identification of channels that may be most sensitive to changes in stream power.  相似文献   
768.
Abstract: Habitat maps are often the core spatially consistent data set on which marine reserve networks are designed, but their efficacy as surrogates for species richness and applicability to other conservation measures is poorly understood. Combining an analysis of field survey data, literature review, and expert assessment by a multidisciplinary working group, we examined the degree to which Caribbean coastal habitats provide useful planning information on 4 conservation measures: species richness, the ecological functions of fish species, ecosystem processes, and ecosystem services. Approximately one‐quarter to one‐third of benthic invertebrate species and fish species (disaggregated by life phase; hereafter fish species) occurred in a single habitat, and Montastraea‐dominated forereefs consistently had the highest richness of all species, processes, and services. All 11 habitats were needed to represent all 277 fish species in the seascape, although reducing the conservation target to 95% of species approximately halved the number of habitats required to ensure representation. Species accumulation indices (SAIs) were used to compare the efficacy of surrogates and revealed that fish species were a more appropriate surrogate of benthic species (SAI = 71%) than benthic species were for fishes (SAI = 42%). Species of reef fishes were also distributed more widely across the seascape than invertebrates and therefore their use as a surrogate simultaneously included mangroves, sea grass, and coral reef habitats. Functional classes of fishes served as effective surrogates of fish and benthic species which, given their ease to survey, makes them a particularly useful measure for conservation planning. Ecosystem processes and services exhibited great redundancy among habitats and were ineffective as surrogates of species. Therefore, processes and services in this case were generally unsuitable for a complementarity‐based approach to reserve design. In contrast, the representation of species or functional classes ensured inclusion of all processes and services in the reserve network.  相似文献   
769.
Abstract:  Scarce resources and competing land-use goals necessitate efficient biodiversity conservation. Combining multicriteria analysis with conservation decision-support tools improves efficiency of conservation planning by maximizing outcomes for biodiversity while minimizing opportunity costs to society. An opportunity cost is the benefit that could have been received by taking an alternative course of action (i.e., costs to society of protecting an area for biodiversity rather than developing it for some other use). Although different ways of integrating multiple opportunity costs into conservation planning have been suggested, there have been no tests as to which method is most efficient. We compared the relative efficiency of 3 such procedures ( Faith & Walker [1996] , Sarkar et al. [2004] , and a procedure of our own design) in a systematic conservation-planning framework for the Milne Bay Province of Papua New Guinea. We devised 14 opportunity costs and assigned these to 3 scenarios representing different conservation planning concerns: food security, macro-economic development, and biodiversity persistence. For each scenario, we compared the efficiency of the 3 methods in terms of amount of biodiversity protected relative to total expenditure for each opportunity cost. All 3 methods captured similar amounts of biodiversity, but differed in total cost. Our method had the least overall cost and was therefore most efficient. Nevertheless, there was a high correlation and geographical concordance among all 3 methods, indicating a high degree of spatial overlap. This suggests that choosing an appropriate approach may often depend on contextual factors related to the design of the planning question, rather than efficiency alone.  相似文献   
770.
The general objective of this paper is to trigger off the development of a more comprehensive approach to Hellenic coastal areas (in the perspective of territorial cohesion), at local level and especially along the non-urban areas close to the sea. Methodological issues linked to the building of an appropriate coastal database constitute the key goal of this paper (the space and time scale, the relationship to the already proposed set of indicators, the impact of driving forces and policies, the possible sources of data and their feasibility etc.). Furthermore, specific emphasis should be given to the choice of new indicators, particularly for the coastal abiotic environment and the land cover/uses along coastal areas, especially near the seafront. Those indicators should be able to aid the formation (in the near future) of an algorithm linked to the total man-made activities in coastal areas. In conclusion, this paper will be considered successful if the just above illustrated objectives could enrich the argument about the typology of coastal areas and the development of a spatial (coastal) observatory. Actually, this paper is part of a broader research of the author regarding the monitoring of coastal spatial changes in different scales (AMICA, “Appraisal of man-made interventions along the Hellenic coastal areas”). This research aims to broaden the coastal knowledge (not only by means of coastal data) on behalf of all stakeholders been implicated into sustainable spatial planning, integrated coastal management and the strategic environmental assessment along coastal areas.
John KiousopoulosEmail:
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