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1.
The phosphorus (P) cycle has been significantly altered by human activities. For this paper, we explored the sustainability of current P flows in terms of resource depletion and the ultimate fate of these flows. The analysis shows that rapid depletion of extractable phosphate rock is not very likely, in the near term. Under best estimates, depletion would be around 20–35%. In worst case scenarios, about 40–60% of the current resource base would be extracted by 2100. At the same time, production will concentrate in Asia, Africa and West Asia, and production costs will likely have increased. As there are no substitutes for phosphorus plant nutrients in agriculture, arguably even partial depletion of P resources may in the long run be relevant for the sustainability of agriculture. Consumption trends lead to large flows of phosphorus to surface water and a considerable build-up of phosphorus in agricultural soils in arable lands. This may allow a reduction in future P fertiliser application rates in crop production. Results also indicate a global depletion of P pools in soils under grassland, which may be a threat to ruminant production.  相似文献   

2.
Towards understanding governance for sustainable urban water management   总被引:1,自引:0,他引:1  
Shifting from traditional, large, centralised infrastructure to alternative, distributed technologies is widely accepted as essential for enabling sustainable water management. Despite technical advances in sustainable urban water management over recent decades, the shift from traditional to more sustainable approaches remains slow. Current research on socio-institutional barriers suggests this poor implementation relates to a limited understanding of the different forms of governance needed to support alternative approaches, rather than the potential ineffectiveness of the technologies and practices. While some governance scholars express preferences for ideal hierarchical, market or network governance approaches, others suggest a hybrid of these approaches may be more appropriate for achieving sustainability. Currently, there is limited commentary about the potential characteristics of sustainable urban water governance. To extend the current scholarship, this paper systematically draws on the tacit knowledge of expert sustainability practitioners to identify potential governance characteristics of sustainable urban water management. In comparison with current urban water scholarship, which is supportive of a network governance approach at a conceptual level, the results strongly suggest that sustainability practitioners see the need for hybrid governance arrangements at a practical and operational level. These hybrid arrangements tended to comprise network and hierarchical approaches with market governance instruments. These insights from practitioners to help identify future research needs, focused on examining interaction among governance approaches at a variety of scales and locations.  相似文献   

3.
Over the last few decades, the Asia–Pacific region has experienced the most dynamic economic development of any of the world's regions, leading to a rapid increase in resource use and associated emissions. The region is now a major driver towards overshooting global resource use limits. In this paper, we provide an estimate of material use and resource efficiency in the Asia–Pacific region and its sub-regions for the first time, to complement existing knowledge on global resource use. We show that the Asia–Pacific has become the single largest user of resources globally, and that the efficiency of resource use in the region decreased over the period 1970–2005. Furthermore we show that the region's share of total resource use is now so significant that decreasing resource efficiency there has driven a decrease in overall global resource efficiency, for the first time in a century. Using an IPAT framework we found that rising per capita incomes contributed more strongly to growing material use than did population growth. Technology did not moderate material use growth to the extent expected. We argue that a failure to make these issues a central and immediate focus of public policy in the Asia–Pacific region would compromise competitiveness, resource security, and poverty reduction in the region over the medium to long term.  相似文献   

4.
Strategies to mitigate anthropogenic climate change recognize that carbon sequestration in the terrestrial biosphere can reduce the build-up of carbon dioxide in the Earth’s atmosphere. However, climate mitigation policies do not generally incorporate the effects of these changes in the land surface on the surface albedo, the fluxes of sensible and latent heat to the atmosphere, and the distribution of energy within the climate system. Changes in these components of the surface energy budget can affect the local, regional, and global climate. Given the goal of mitigating climate change, it is important to consider all of the effects of changes in terrestrial vegetation and to work toward a better understanding of the full climate system. Acknowledging the importance of land surface change as a component of climate change makes it more challenging to create a system of credits and debits wherein emission or sequestration of carbon in the biosphere is equated with emission of carbon from fossil fuels. Recognition of the complexity of human-caused changes in climate does not, however, weaken the importance of actions that would seek to minimize our disturbance of the Earth’s environmental system and that would reduce societal and ecological vulnerability to environmental change and variability.  相似文献   

5.
Sustainable fisheries management into the future will require both understanding of and adaptation to climate change. A risk management approach is appropriate due to uncertainty in climate projections and the responses of target species. Management strategy evaluation (MSE) can underpin and support effective risk management. Climate change impacts are likely to differ by species and spatially. We use a spatial MSE applied to a multi-species data-poor sea cucumber/béche-de-mer fishery to demonstrate the utility of MSE to test the performance of alternative harvest strategies in meeting fishery objectives; this includes the ability to manage through climate variability and change, and meeting management objectives pertaining to resource status and fishery economic performance. The impacts of fishing relative to the impacts of climate change are distinguished by comparing future projection distributions relative to equivalent no-fishing no-climate-change trials. The 8 modelled species exhibit different responses to environmental variability and have different economic value. Status quo management would result in half the species falling below target levels, moderate risks of overall and local depletion, and significant changes in species composition. The three simple strategies with no monitoring (spatial rotation, closed areas, multi-species composition) were all successful in reducing these risks, but with fairly substantial decreases in the average profit. Higher profits (for the same risk levels) could only be achieved with strategies that included monitoring and hence adaptive management. Spatial management approaches based on adaptive feedback performed best overall.  相似文献   

6.
In this paper, we present four model-based scenarios exploring the potential for resource efficiency for energy, land and phosphorus use, and implications for resource depletion, climate change and biodiversity. The scenarios explored include technological improvements as well as structural changes in production systems and lifestyle changes. Many of such changes have long lead times, requiring up front and timely investments in infrastructure, innovative incentive structures and education. For simulating the scenarios we applied the IMAGE modelling framework, with a time horizon until 2050.Our findings confirm a large potential for more efficient resource use: our (no new policies) baseline scenario shows a global increase, between 2010 and 2050, by 80% of primary energy use, 4% of arable land and 40% of phosphorus fertilisers. These numbers are reduced to +25% (primary energy), −9% (arable land) and +9% (phosphorus) in the global resource efficiency scenario. Baseline developments and resource efficiency opportunities vary strikingly among regions, resources and sectors. Phosphorus use, for example, is expected to increase most on croplands in developing countries, whereas the largest potential for phosphorus use efficiency lies in the livestock sector and urban sewage treatment in industrialised countries. Consequently, while resource efficiency resonates well as a general notion in policy thinking, concrete policies need to be region-specific, resource-specific and sector-specific.Efficiency efforts on one resource tend to contribute to efficient use of other resources and to benefit the environment. There are also trade-offs, however, and the synergies analysed do not make problem-specific policies redundant: in 2050, the global resource efficiency scenario presents higher phosphorus use and higher use of fossil fuels than in 2010; greenhouse gas emission targets are met by half; and biodiversity loss slows down but is not halted. Moreover, part of the efficiency gains in land and phosphorus use is sacrificed when this scenario is combined with ambitious climate policy, due to the substantial resource requirements for the deployment of bio-energy—albeit much less than in a scenario without more efficient resource use.  相似文献   

7.
Water resource management in South Florida faces nearly intractable problems, in part due to weather and climate variability. Rising sea level and coastal storm surge are two phenomena with significant impacts on natural systems, fresh water supplies and flood drainage capability. However, decision support information regarding management of water resources in response to storm surge is not well developed. In an effort to address this need we analyze long term tidal records from Key West, Pensacola and Mayport Florida to extract surge distributions, to which we apply a nonlinear eustatic sea level rise model to project storm surge return levels and periods. Examination of climate connections reveals a statistically significant dependence between surge distributions and the Atlantic Multidecadal Oscillation (AMO). Based on a recent probabilistic model for AMO phase changes, we develop AMO-dependent surge distributions. These AMO-dependent surge projections are used to examine the flood control response of a coastal water management structure as an example of how climate dependent water resource forcings can be used in the formulation of decision support tools.  相似文献   

8.
Considering climatic uncertainties in management planning is a prerequisite for sustainable forest management (SFM). The aim of the study was to evaluate climate change vulnerability of the current SFM strategy for commercial forests managed by the Austrian Federal Forests. To that end vulnerability indicators were defined in a stakeholder process (selected indicators were productivity, timber and carbon stocks, biodiversity, disturbances, a tree species’ position in fundamental niche space, silvicultural flexibility and cost intensity) and their performance under climate change scenarios assessed with an ecosystem model. Multi criteria analysis techniques were employed in a partial aggregation of indicators to locate forest stands on a vulnerability surface. Results revealed high vulnerability particularly in the second half of the twenty-first century, where 39.6% of the 164.550 ha study area were assessed highly vulnerable to climate change, indicating a strong decline in the functions and services represented by the indicator system. Water-limited sites on calcareous bedrock were most negatively affected whereas assessment units at higher altitudes responded predominately positive to climate warming. The presented approach, transparently integrating multiple management objectives and allowing a quantitative comparison of vulnerabilities between sites and management strategies, contributes to the development of operational and efficient climate change adaptation measures in forest management.  相似文献   

9.
Exploring adaptation pathways into an uncertain future can support decisionmaking in achieving sustainable water management in a changing environment. Our objective is to develop and test a method to identify such pathways by including dynamics from natural variability and the interaction between the water system and society. Present planning studies on long-term water management often use a few plausible futures for one or two projection years, ignoring the dynamic aspect of adaptation through the interaction between the water system and society. Our approach is to explore pathways using multiple realisations of transient scenarios with an Integrated Assessment Meta Model (IAMM). This paper presents the first application of the method using a hypothetical case study. The case study shows how to explore and evaluate adaptation pathways. With the pathways it is possible to identify opportunities, threats, timing and sequence of policy options, which can be used by policymakers to develop water management roadmaps into the future. By including the dynamics between the water system and society, the influence of uncertainties in both systems becomes clearer. The results show, among others, that climate variability rather than climate change appears to be important for taking decisions in water management.  相似文献   

10.
11.
Recently, the depletion in ozone and aerosol extinctions inside Antarctic Spring westerly vortex and condensa-tion nuclei enhancement events in the mid latitudes stratosphere were related to downward transport of aerosols by subsidence and sedimentation. However, the problems associated with such hypothesis would keep a constraint on photochemical theories on ozone hole and stratospheric condensation nuclei (CN) events. Alternately, the gross fea-tures of aerosol hole are better explicable assuming a reversed residual circulation. This opens a path for combined operation on ozone by both photochemistry and dynamics in the same space domain.Independently, we relate the CN events to the growth and transport of negative ion complexes above the Peak of Junge Layer (PJL) without invoking photochemistry in order to be consistant with the observed interhemispheric dif-ferences in the planetary wave activity and CN concentration.  相似文献   

12.
Climate change is leading to a redistribution of marine species, altering ecosystem dynamics as species extend or shift their geographic ranges polewards with warming waters. In marine systems, range shifts have been observed in a wide diversity of species and ecosystems and are predicted to become more prevalent as environmental conditions continue to change. Large-scale shifts in the ranges of marine species will likely have dramatic socio-economic and management implications. Australia provides a unique setting in which to examine the range of consequences of climate-induced range shifts because it encompasses a diverse range of ecosystems, spanning tropical to temperate systems, within a single nation and is home to global sea surface temperature change ‘hotspots’ (where range shifts are particularly likely to occur). We draw on global examples with a particular emphasis on Australian cases to evaluate these consequences. We show that in Australia, range shifts span a variety of ecosystem types, trophic levels, and perceived outcomes (i.e., negative versus positive). The effect(s) of range shifts on socio-economic change variables are rarely reviewed, yet have the potential to have positive and/or negative effects on economic activities, human health and ecosystem services. Even less information exists about potential management responses to range-shifting species. However, synthesis of these diverse examples provides some initial guidance for selecting effective adaptive response strategies and management tools in the face of continuing climate-mediated range shifts.  相似文献   

13.
Water resources, and in particular run-off, are significantly affected by climate variability. At present, there are few examples of how the water management sector integrates information about changing intra-annual climate conditions in a systematic manner in developing countries. This paper, using the case study of Cape Town in the Western Cape, South Africa, identifies processes and products to facilitate increased uptake of seasonal climate forecasts among water resource managers. Results suggest that existing seasonal forecasts do not focus enough on specific users’ needs. In order to increase uptake, forecasts need to include information on the likely impact of precipitation variability on runoff and water availability. More opportunities are also needed for those with climate knowledge to interact with water resource managers, particularly in the developing country context where municipal managers’ capacity is strained. Although there are challenges that need to be overcome in using probabilistic climate information, seasonal forecast information tailored to the needs of water resource planners has the potential to support annual planning and is therefore a means of adapting to climate change.  相似文献   

14.
The use of wild species is extensive in both high- and low-income countries. At least 50,000 wild species are used by billions of people around the world for food, energy, medicine, material, education or recreation, contributing significantly to efforts to achieve the United Nations Sustainable Development Goals. However, overexploitation remains a major threat to many wild species. Ensuring and enhancing the sustainability of use of wild species is thus essential for human well-being and biodiversity conservation. Globally, the use of wild species is increasing due to growing human demand and efficiency, but its sustainability varies and depends on the social-ecological contexts in which the use occurs. Multiple environmental and social (including economic) drivers affect the sustainability of use of wild species, posing major current and future challenges. In particular, climate change has already increased the vulnerability of many uses and is expected to increase it further in the coming decades, while global and illegal trades are, in many cases, key drivers of unsustainability. There is no single “silver bullet” policy to address these and other major challenges in the sustainable use of wild species. Rather, effective policies need to integrate inclusive actions at multiple scales that adopt right-based approaches, pay attention to equitable distribution of access and costs and benefits, employ participatory processes, strengthen monitoring programs, build robust customary or government institutions and support context-specific policies, as well as adaptive management.  相似文献   

15.
Solar radiation management techniques are a class of geoengineering methods designed to reflect some of the inbound sunlight back into space with the intended effect of arresting further warming of the planet and thus counteracting global warming. In this article we examine current debates on solar radiation management governance, clarifying a number of assumptions that persist and why these require further scrutiny. Building on existing research we articulate a more critical role that the social sciences should be playing in public engagement with solar radiation management. We develop a deliberative focus group methodology that aims to open up deliberation on the technology, focusing explicitly on the kinds of world that its deployment would bring into being. Our findings, based on an analysis of public discourse, suggest that solar radiation management would be publicly acceptable only under very specific, and highly contingent, conditions. Given the sensed implausibility of these conditions being realised in the real world, we set out the implications for solar radiation management governance. We explain why solar radiation management was perceived as likely to create a particular kind of world, one with an increased probability of geopolitical conflict, a new condition of global experimentality, and major threats to democratic governance. How to bring these issues into solar radiation management governance entails an important but challenging role for the social sciences.  相似文献   

16.
Brief information about principles of creation and structure of nature-technology complex of the space monitoring system in the northern Russian regions for its sustainable and security development management is under consideration.  相似文献   

17.
D. I. Smith 《Climatic change》1993,25(3-4):319-333
Most scenarios of greenhouse climate change are obtained from general circulation models. These provide poor information on changes to extreme events. It is therefore, difficult to convert changes of flood frequency into their impact on flood damages. The procedures for estimating urban flood losses are outlined. Australian case studies illustrate the possible effects of greenhouse-induced changes in comparison to the variability under current climate; changes in urban flood losses for small and large catchments; and the implications for dam design. In all cases, relatively small increases in flood frequency would cause significant increases in loss. The policy implications are outlined, it must not be assumed that the availability of more precise data on future flood frequencies will be matched by policy response in the field of flood plain management.  相似文献   

18.
This study investigates the influence of climate change on groundwater availability, and thereby, irrigation across political boundaries within the US High Plains aquifer. A regression model is developed to predict changes in irrigation according to predicted changes in precipitation and temperature from a downscaled dataset of 32 general circulation models (GCMs). Precipitation recharge changes are calculated with precipitation-recharge curves developed for prognostic representations of precipitation across the Nebraska-Colorado-Kansas area and within the Republican River Basin focal landscape. Irrigation-recharge changes are scaled with changes in irrigation. The groundwater responses to climate forcings are then simulated under new pumping and recharge rates using a MODFLOW groundwater flow model. Results show that groundwater pumping and recharge both will increase and that the effects of groundwater pumping will overshadow those from natural fluctuations. Groundwater levels will decline more in areas with irrigation-driven decreasing trends in the baseline. The methodologies and predictions of this study can inform long-term water planning and the design of management strategies that help avoid and resolve water-related conflicts, enabling irrigation sustainability.  相似文献   

19.
This editorial essay conveys a clear message: The overuse of our fossil fuel resources especially in the North, and the overpopulation in many parts of the South, result in an unacceptable stress to Earth. This manifests itself in some of the most serious threats to mankind, such as global climatic change, environmental degradation, food shortage, hunger, poverty, and migration. It is the purpose of this editorial essay to make a contribution toward a reduction of some of these threats, notably those from climatic change. Specifically, I present a tractable climatic and environmental protection strategy which is designed to give concrete answers to such seemingly simple questions as: What has to be done? (This depends e.g. on the concentration stabilization objective of the Rio Climate Convention, and the global warming ceiling of the Enquete-Commission of the German Parliament). By whom does it have to be done? (This addresses the secret of a successful protection strategy which involves a fair burden sharing among the world's countries). When does it have to be done? (This discusses the problem of setting tractable, i.e. differentiated and binding emission targets). How can it be done? (This relates to individual countries, states, and municipalities. It is demonstrated for Germany how her commitment of a 25 to 30% CO2 reduction by 2005 can be achieved.) Moreover, the question is addressed: How many people and how much fossil fuel use can our planet stand? The major result is that without self-restraint climate and ecosystem protection cannot be maintained, because it is incompatible with trends in the wasteful fossil fuel use in the North and strong population growth in the South. Finally, a plea is made to share responsibility on the road toward a sustainable future.  相似文献   

20.
Some connections between aerosols, atmospheric transport, and relative humidity are investigated based on measurements at Basic Environmental Observatory (BEO) station, peak Musala (2,925 masl) for the period January 2009–January 2010. Data are chosen at 0:00 and 12:00 GMT every day. Main methods employed in this research are statistical—nonparametric tests of Mann–Whitney and Spearman. The main conclusion is that greater aerosol load at peak Musala is connected with transport of air masses from north to east horizon quarters. Bigger particles with longer lifetimes come from there. Air coming from the south horizon quarter is aerosol clearer. Relative humidity shows opposite distribution—higher values for transport from south horizon quarter. Correlation between this parameter and aerosols is negative with significant but small value. Distribution of blue, green, and red scattering and backscattering coefficients is similar to distribution of total aerosol concentration. Correlations between scattering and backscattering coefficients and total aerosol concentration are significant and positive. Courses of total aerosol concentration; diameter of particles with maximum concentration; and blue, green, and red scattering and backscattering coefficients have summer maximum and winter minimum. Diurnal course of total aerosol concentration in the two main seasons, winter (January) and summer (July), has day maximum and night minimum. Aerosols at peak Musala are predominantly of transparent or translucent type. The calculation of Ångström exponent α is more precise by using scattering coefficients. The nephelometers data could successfully characterize the haziness of the atmosphere above peak Musala.  相似文献   

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