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1.
Micronutrient deficiencies constitute a pressing public health concern, especially in developing countries. As a dense source of bioavailable nutrients, aquatic foods can help alleviate such deficiencies. Developing aquaculture that provides critical micronutrients without sacrificing the underlying environmental resources that support these food production systems is therefore essential. Here, we address these dual challenges by optimizing nutrient supply while constraining the environmental impacts from aquaculture. Using life cycle assessment and nutritional data from Indonesia, a top aquaculture producer, we sought to identify aquaculture systems that increase micronutrient supplies and reduce environmental impacts (e.g., habitat destruction, freshwater pollution, and greenhouse gas emissions). Aquaculture systems in Indonesia vary more by environmental impacts (e.g. three order of magnitude for fresh water usage) than by nutritional differences (approximately ± 50% differences from mean relative nutritional score). Nutritional-environmental tradeoffs exist, with no single system offering a complete nutrition-environment win–win. We also find that previously proposed future aquaculture paths suboptimally balance nutritional and environmental impacts. Instead, we identify optimized aquaculture production scenarios for 2030 with nutrient per gram densities 105–320% that of business-as-usual production and with environmental impacts as low as 25% of those of business-as-usual. In these scenarios Pangasius fish (Pangasius hypophthalmus) ponds prove desirable due to their low environmental impacts, but average relative nutrient score. While the environmental impacts of the three analyzed brackish water systems range from average to high compared to other aquaculture systems, their nutritional attributes render them necessary when maximizing all nutrients except vitamin A. Common carp (Cyprinus carpio) ponds also proved essential in maximizing zinc and omega n-3, while Tilapia (Oreochromis niloticus) cages were necessary in optimizing the production of calcium and vitamin A. These optimal aquaculture strategies also reduce business-as-usual demand for wild fish-based feed by 0–30% and mangrove expansion by 0–75% with no additional expansion into inland open waters and freshwater ponds. As aquaculture production expands globally, optimization presents a powerful opportunity to reduce malnutrition rates at reduced environmental impacts. The proposed reorientation promotes UN sustainable development goals 2 (zero hunger), 3 (health), 13 (climate action) and 14 (life under water) and requires concerted and targeted policy changes.  相似文献   

2.
Analyzing the spatial and temporal properties of information flow with a multi-century perspective could illuminate the sustainability of human resource-use strategies. This paper uses historical and archaeological datasets to assess how spatial, temporal, cognitive, and cultural limitations impact the generation and flow of information about ecosystems within past societies, and thus lead to tradeoffs in sustainable practices. While it is well understood that conflicting priorities can inhibit successful outcomes, case studies from Eastern Polynesia, the North Atlantic, and the American Southwest suggest that imperfect information can also be a major impediment to sustainability. We formally develop a conceptual model of Environmental Information Flow and Perception (EnIFPe) to examine the scale of information flow to a society and the quality of the information needed to promote sustainable coupled natural-human systems. In our case studies, we assess key aspects of information flow by focusing on food web relationships and nutrient flows in socio-ecological systems, as well as the life cycles, population dynamics, and seasonal rhythms of organisms, the patterns and timing of species’ migration, and the trajectories of human-induced environmental change. We argue that the spatial and temporal dimensions of human environments shape society’s ability to wield information, while acknowledging that varied cultural factors also focus a society’s ability to act on such information. Our analyses demonstrate the analytical importance of completed experiments from the past, and their utility for contemporary debates concerning managing imperfect information and addressing conflicting priorities in modern environmental management and resource use.  相似文献   

3.
Environmental change in grasslands: Assessment using models   总被引:7,自引:0,他引:7  
Modeling studies and observed data suggest that plant production, species distribution, disturbance regimes, grassland biome boundaries and secondary production (i.e., animal productivity) could be affected by potential changes in climate and by changes in land use practices. There are many studies in which computer models have been used to assess the impact of climate changes on grassland ecosystems. A global assessment of climate change impacts suggest that some grassland ecosystems will have higher plant production (humid temperate grasslands) while the production of extreme continental steppes (e.g., more arid regions of the temperate grasslands of North America and Eurasia) could be reduced substantially. All of the grassland systems studied are projected to lose soil carbon, with the greatest losses in the extreme continental grassland systems. There are large differences in the projected changes in plant production for some regions, while alterations in soil C are relatively similar over a range of climate change projections drawn from various General Circulation Models (GCM's). The potential impact of climatic change on cattle weight gains is unclear. The results of modeling studies also suggest that the direct impact of increased atmospheric CO2 on photosynthesis and water use in grasslands must be considered since these direct impacts could be as large as those due to climatic changes. In addition to its direct effects on photosynthesis and water use, elevated CO2 concentrations lower N content and reduce digestibility of the forage.  相似文献   

4.
Both supply and demand side changes are necessary to achieve a sustainable food system. However, the weight accorded to these depends on one’s view of what the priority goals are for the food system and the extent to which production systems versus consumption patterns are open to change. Some stakeholders see the problem as one of ‘not enough food’ and focus on the need to sustainably increase supply, while others consider the resource demanding and ‘greedy’ consumption patterns of the Western world as the main problem and emphasize the need to shift diets. In this study global land use and greenhouse gas emissions are estimated for a set of scenarios, building on four ‘livestock futures’ reflecting these different perspectives. These scenarios are: further intensification of livestock systems; a transition to plant-based eating; a move towards artificial meat and dairy; and a future in which livestock production is restricted to the use of ‘ecological leftovers’ i.e. grass from pastures, food waste and food and agricultural byproducts. Two dietary variants for each scenario are modelled: 1) a projected diet following current trends and 2) a healthy diet with more fruits and vegetables and fewer animal products, vegetable oils and sugar. Livestock production in all scenarios (except the baseline scenario) was assumed to intensify to current levels of intensive production in North-Western Europe. For each scenario, several variant assumptions about yield increases and waste reductions were modelled. Results show that without improvements in crop productivity or reductions on today’s waste levels available cropland will only suffice if production of all protein currently supplied by animal foods is replaced by (hypothetical) artificial variants not requiring any land. With livestock intensities corresponding to current ones in North-Western Europe and with yield gaps closed by 50% and waste reduced by 50%, available cropland will suffice for all scenarios that include a reduction of animal products and/or a transition to poultry or aquaculture. However, in the scenario based on an extrapolation of current consumption patterns (animal product amounts and types consumed in proportions corresponding to the current average consumption in different world regions) and with livestock production based on feed from cropland, available cropland will not be enough. The scenario that makes use of pastures for ruminant production and food waste for pigs, uses considerably less cropland and could provide 40–56 kg per capita per year of red meat. However, such a livestock future would not reduce GHG emissions from agriculture on current levels. This study confirms previous research that to achieve a sustainable food future, action is needed on all fronts; improved supply and reduced demand and waste.  相似文献   

5.
Maintaining food security and environmental integrity over time requires a transition towards sustainable food systems. This paper analyzes different dimensions of national food supply sustainability on a global scale. By focusing on four food staples: wheat, rice, maize, and soybeans, the analysis identifies production regions that are more or less environmentally sustainable. It explores the dependence of different countries on calories supplied by these regions. These four staples' production requires 648 million hectares of cropland and about 559 cubic kilometers of irrigation water. It also leads to several environmental impacts, including potential soil loss and species loss. Yet, these impacts and pressures are spread unevenly across agricultural systems.We find that over one-third of the global calorie intake originates from regions with a high per ton environmental impacts. Although most consumed calories are from domestic sources, traded calories mostly originate from environmentally suitable production regions, increasing importing countries' food supply sustainability. This analysis also reveals interregional tradeoffs, where food imports into one region (increased food provision) is associated with high environmental impact in production regions. Further, this typology allows identifying an elusive, often overlooked interregional connection. That is the potential loss of future ecosystem service flow from countries with the lower gross domestic product per capita and high biodiversity. To date, those countries rely primarily on domestic staple production, which puts pressure on vulnerable local ecosystems. Species loss in those regions reduces the potential future interregional flows of genetic material. Alternatively, conservation combined with food imports can maintain diversity and the potential flow of genetic material from those regions. The functional regions typology provides a complete assessment of the interregional connections that make up the global food system. Therefore, it is useful for informing policy analysts and policymakers of a broader collection of stakeholders regarding the local environment. It also provides essential information about the suitability of different policy mechanisms to govern interregional systems. Future research shall expand the functional regions' typology to include additional environmental and human-related (e.g., technological), to cover more crops, and to account for other food categories, such as meat.  相似文献   

6.
Food security for a growing world population is high on the list of grand sustainability challenges, as is reducing the pace of biodiversity loss in landscapes of food production. Here we shed new insights on areas that harbor place specific social memories related to food security and stewardship of biodiversity. We call them bio-cultural refugia. Our goals are to illuminate how bio-cultural refugia store, revive and transmit memory of agricultural biodiversity and ecosystem services, and how such social memories are carried forward between people and across cohorts. We discuss the functions of such refugia for addressing the twin goals of food security and biodiversity conservation in landscapes of food production. The methodological approach is first of its kind in combining the discourses on food security, social memory and biodiversity management. We find that the rich biodiversity of many regionally distinct cultural landscapes has been maintained through a mosaic of management practices that have co-evolved in relation to local environmental fluctuations, and that such practices are carried forward by both biophysical and social features in bio-cultural refugia including; genotypes, artifacts, written accounts, as well as embodied rituals, art, oral traditions and self-organized systems of rules. Combined these structure a diverse portfolio of practices that result in genetic reservoirs—source areas—for the wide array of species, which in interplay produce vital ecosystem services, needed for future food security related to environmental uncertainties, volatile financial markets and large scale conflicts. In Europe, processes related to the large-scale industrialization of agriculture threaten such bio-cultural refugia. The paper highlights that the dual goals to reduce pressures from modern agriculture on biodiversity, while maintaining food security, entails more extensive collaboration with farmers oriented toward ecologically sound practices.  相似文献   

7.
Mapping global land system archetypes   总被引:1,自引:0,他引:1  
Land use is a key driver of global environmental change. Unless major shifts in consumptive behaviours occur, land-based production will have to increase drastically to meet future demands for food and other commodities. One approach to better understand the drivers and impacts of agricultural intensification is the identification of global, archetypical patterns of land systems. Current approaches focus on broad-scale representations of dominant land cover with limited consideration of land-use intensity. In this study, we derived a new global representation of land systems based on more than 30 high-resolution datasets on land-use intensity, environmental conditions and socioeconomic indicators. Using a self-organizing map algorithm, we identified and mapped twelve archetypes of land systems for the year 2005. Our analysis reveals similarities in land systems across the globe but the diverse pattern at sub-national scales implies that there are no ‘one-size-fits-all’ solutions to sustainable land management. Our results help to identify generic patterns of land pressures and environmental threats and provide means to target regionalized strategies to cope with the challenges of global change. Mapping global archetypes of land systems represents a first step towards better understanding the global patterns of human–environment interactions and the environmental and social outcomes of land system dynamics.  相似文献   

8.
Meeting the food needs of the growing and increasingly affluent human population with the planet’s limited resources is a major challenge of our time. Seen as the preferred approach to global food security issues, ‘sustainable intensification’ is the enhancement of crop yields while minimizing environmental impacts and preserving the ability of future generations to use the land. It is still unclear to what extent sustainable intensification would allow humanity to meet its demand for food commodities. Here we use the footprints for water, nitrogen, carbon and land to quantitatively evaluate resource demands and greenhouse gas (GHG) emissions of future agriculture and investigate whether an increase in these environmental burdens of food production can be avoided under a variety of dietary scenarios. We calculate average footprints of the current diet and find that animal products account for 43–87% of an individual’s environmental burden – compared to 18% of caloric intake and 39% of protein intake. Interestingly, we find that projected improvements in production efficiency would be insufficient to meet future food demand without also increasing the total environmental burden of food production. Transitioning to less impactful diets would in many cases allow production efficiency to keep pace with growth in human demand while minimizing the food system’s environmental burden. This study provides a useful approach for evaluating the attainability of sustainable targets and for better integrating food security and environmental impacts.  相似文献   

9.
Designing effective mitigation policies for greenhouse gas (GHG) emissions from agriculture requires understanding the mechanisms by which management practices affect emissions in different agroclimatic conditions. Agricultural GHG emissions and carbon sequestration potentials have been extensively studied in the Mediterranean biome, which is a biodiversity hot spot that is highly vulnerable to environmental changes. However, the absolute magnitude of GHG emissions and the extent to which research efforts match these emissions in each production system, are unknown. Here, we estimated GHG emissions and potential carbon sinks associated with crop and livestock production systems in the Mediterranean biome, covering 31 countries and assessing approximately 10,000 emission items. The results were then combined with a bibliometric assessment of 797 research publications to compare emissions estimates obtained with research efforts for each of the studied items. Although the magnitude of GHG emissions from crop production and the associated carbon sequestration potential (261 Tg CO2eq yr−1) were nearly half of those from livestock production (367 Tg CO2eq yr−1), mitigation research efforts were largely focused on the former. As a result, the relative research intensity, which relates the number of publications to the magnitude of emissions, is nearly one order of magnitude higher for crop production than for livestock production (2.6 and 0.4 papers Tg CO2eq−1, respectively). Moreover, this mismatch is even higher when crop and livestock types are studied separately, which indicates major research gaps associated with grassland and many strategic crop types, such as fruit tree orchards, fiber crops, roots and tubers. Most life cycle assessment studies do not consider carbon sequestration, although this single process has the highest magnitude in terms of annual CO2eq. In addition, these studies employ Tier 1 IPCC factors, which are not suited for use in Mediterranean environments. Our analytical results show that a strategic plan is required to extend on-site field GHG measurements to the Mediterranean biome. Such a plan needs to be cocreated among stakeholders and should be based on refocusing research efforts to GHG balance components that have been afforded less attention. In addition, the outcomes of Mediterranean field studies should be integrated into life cycle assessment-based carbon footprint analyses in order to avoid misleading conclusions.  相似文献   

10.
Recent moves by national and local policy makers have sought to encourage individuals to engage in a wide range of pro-environmental practices to address both discrete environmental problems and major, global challenges such as climate change. The major framing device for these developments is the notion of ‘citizen–consumers’, which positions individual ecological responsibilities alongside consumer choice logics in a Neo-liberal socio-economic framework. In the environmental social sciences, there have been recent moves to interpret the citizen–consumer through adopting a social practices approach, which advances the notion that in understanding environmental commitments, a deeper appreciation of underlying norms, values, identity politics and consumption is required to uncover the complex processes that lead to environmental practices in specific contexts. This paper argues that whilst these approaches have considerable utility in tracing the normalisation of established and discrete environmental practices in particular contexts, the issue of climate change represents an independent and over-arching discursive conflict between new and embedded practices that challenges the ability of citizen–consumers to act as agents for change. Accordingly, the data presented in this paper suggest that climate change can be seen as an unsettling and dynamic issue that generates discursive conflict in its own right around fundamental issues of knowledge, responsibility, scale and place. The paper therefore argues that a new and more critical perspective is required within environmental social science to understand (conflicting) discourses of sustainable living between the ‘passive’ normalisation of conventional environmental practice and the ‘contested’ ambiguities of climate change.  相似文献   

11.
The paper sets out a proposal for bridging and linking three approaches to the analysis of transitions to sustainable and low-carbon societies: quantitative systems modelling; socio-technical transition analysis; and initiative-based learning. We argue that each of these approaches presents a partial and incomplete picture, which has implications for the quality and usefulness of the insights they can deliver for policy and practice. A framework for bridging these different approaches promises to enrich each of the approaches, while providing the basis for a more robust and complete analysis of sustainable transitions pathways that serves better to address questions and dilemmas faced by decision-makers and practitioners. We elaborate five key challenges for the analysis and governance of transitions pathways, and compare the three approaches in relation to each of these. We suggest an integration strategy based on alignment, bridging, and iteration, arguing that a structured dialogue between practitioners of different approaches is needed. In practical terms, such a dialogue would be organised around three areas of joint knowledge production: defining common analytical or governance problems to be tackled through integration; establishing shared concepts (boundary objects); and establishing operational bridging devices (data and metrics, pathways evaluation and their delivery). Such processes could include experts and societal partners. We draw conclusions about future research perspectives and the role of analysis in transitions governance.  相似文献   

12.
Changes in the agriculture sector are essential to mitigate and adapt to climate change, meet growing food demands, and improve the livelihoods of poor smallholder producers. What agricultural strategies are needed to meet these challenges? To what extent are there synergies among these strategies? This paper examines these issues for smallholder producers in Kenya across several agroecological zones. Several practices emerge as triple wins, supporting climate adaptation, greenhouse gas mitigation, and profitability goals. In particular, integrated soil fertility management and improved livestock feeding are shown to provide multiple benefits across all agroecological zones examined. Triple wins of other agricultural practices are limited to specific agroecological zones. Irrigation and soil and water conservation, for example, are essential for adaptation, mitigation, and profitability in arid areas. The results suggest that agricultural investments targeted toward these triple-win strategies will have the greatest payoff in terms of increased resilience of farm and pastoralist households and global climate change mitigation. To reap the benefits of triple-win strategies will require that policymakers, researchers, and practitioners move away from isolated approaches focused on either adaptation or mitigation or rural income generation toward a more holistic assessment of joint strategies as well as their tradeoffs and synergies.  相似文献   

13.
Climate and current anthropogenic impacts on fisheries   总被引:1,自引:1,他引:0  
Human impacts on marine fisheries go back many centuries or even thousands of years in some coastal areas. Full global exploitation of the most productive fish stocks probably occurred around 1990. Many stocks have been overexploited and the assessment and management required to rein this in and to combat other human pressures, such as pollution, has been slow to mature, but is showing positive trends. The need to protect marine ecosystems for their intrinsic value and for the services they provide has also been recognised and is being embodied in legislation and turned into operational tools. As with terrestrial systems, it will not be easy to find acceptable balances between food production and conservation objectives. Climate change imposes a new set of pressures on marine ecosystems; increasing temperature, reduced salinity in some enclosed seas and coastal areas, changing windfields and seasonality, acidification, deoxygenation and rising sea level will all affect the productivity and distribution of marine life. We can detect some of the consequences already but prediction is very difficult for a variety of reasons. In spite of these difficulties it is possible to map out robust guidance on the kind of research that will help us to adapt and on the development of practices and management that will insure against future change.  相似文献   

14.
Sudden disruptions, or shocks, to food production can adversely impact access to and trade of food commodities. Seafood is the most traded food commodity and is globally important to human nutrition. The seafood production and trade system is exposed to a variety of disruptions including fishery collapses, natural disasters, oil spills, policy changes, and aquaculture disease outbreaks, aquafeed resource access and price spikes. The patterns and trends of these shocks to fisheries and aquaculture are poorly characterized and this limits the ability to generalize or predict responses to political, economic, and environmental changes. We applied a statistical shock detection approach to historic fisheries and aquaculture data to identify shocks over the period 1976–2011. A complementary case study approach was used to identify possible key social and political dynamics related to these shocks. The lack of a trend in the frequency or magnitude of the identified shocks and the range of identified causes suggest shocks are a common feature of these systems which occur due to a variety, and often multiple and simultaneous, causes. Shocks occurred most frequently in the Caribbean and Central America, the Middle East and North Africa, and South America, while the largest magnitude shocks occurred in Asia, Europe, and Africa. Shocks also occurred more frequently in aquaculture systems than in capture systems, particularly in recent years. In response to shocks, countries tend to increase imports and experience decreases in supply. The specific combination of changes in trade and supply are context specific, which is highlighted through four case studies. Historical examples of shocks considered in this study can inform policy for responding to shocks and identify potential risks and opportunities to build resilience in the global food system.  相似文献   

15.
不同气候情景下华北平原蒸发与径流时空变化分析   总被引:1,自引:0,他引:1  
基于中国气象局国家气候中心生成的IPCC第四次评估报告中23种气候模式的情景集成数据,采用Schreiber公式和Thornthwaite方法计算实际蒸发和径流,分析了2001-2060年SRES A1B、A2和 B1这3种情景下,华北平原气温、降水、蒸发与径流的时空变化。结果表明:未来华北平原气温呈升高趋势,且冬半年升温幅度大于夏半年;降水亦呈增加趋势,而冬半年降水增加幅度小于夏半年;与此相应,华北平原蒸发和年径流呈增加趋势,增幅和空间差异随时间推移而增大,到2041-2060年蒸发将上升7.1%~9.4%,径流将增加8.7%~10.7%。  相似文献   

16.
Latin American smallholder coffee farmers linked with fair trade and organic markets are frequently cited as models for sustainable food systems. Yet many experience seasonal hunger, which is a very common, but understudied, form of food insecurity. Northern Nicaragua's highlands include well-organized cooperatives, high rural poverty rates, and rain dependent farms, offering a compelling study area to understand what factors are associated with seasonal hunger. This participatory mixed methods study combines data from observations, interviews and focus groups with results from a survey of 244 cooperative members. It finds that seasonal hunger is influenced by multiple factors, including: (1) annual cycles of precipitation and rising maize prices during the lean months; (2) inter annual droughts and periodic storms; and (3) the long-term inability of coffee harvests and prices to provide sufficient income. Sampled households experienced an average of about 3 months of seasonal hunger in 2009. A series of five least squares regression models find the expected significant impacts of corn harvest quantity, farm area, improved grain storage, and household incomes, all inversely correlated with lean months. Unanticipated results include the finding that households with more fruit trees reported fewer lean months, while the predominant environmentally friendly farming practices had no discernable impacts. The presence of hunger among producers challenges sustainable coffee marketing claims. We describe one example of a partnership-based response that integrates agroecological farm management with the use of fair trade cooperative institutions to re-localize the corn distribution system. Increased investments and integrated strategies will be needed to reduce threats to food security, livelihoods, and biodiversity associated with the rapid spread of coffee leaf rust and falling commodity prices.  相似文献   

17.
Scenarios describe plausible and internally consistent views of the future. They can be used by scientists, policymakers and entrepreneurs to explore the challenges of global environmental change given an appropriate level of spatial and sectoral detail and systematic development. We followed a nine-step protocol to extend and enrich a set of global scenarios – the Shared Socio-economic Pathways (SSPs) – providing regional and sectoral detail for European agriculture and food systems using a one-to-one nesting participatory approach. The resulting five Eur-Agri-SSPs are titled (1) Agriculture on sustainable paths, (2) Agriculture on established paths, (3) Agriculture on separated paths, (4) Agriculture on unequal paths, and (5) Agriculture on high-tech paths. They describe alternative plausible qualitative evolutions of multiple drivers of particular importance and high uncertainty for European agriculture and food systems. The added value of the protocol-based storyline development process lies in the conceptual and methodological transparency and rigor; the stakeholder driven selection of the storyline elements; and consistency checks within and between the storylines. Compared to the global SSPs, the five Eur-Agri-SSPs provide rich thematic and regional details and are thus a solid basis for integrated assessments of agriculture and food systems and their response to future socio-economic and environmental changes.  相似文献   

18.
In the face of climate change and extreme weather events which continue to have significant impacts on agricultural production, climate-smart agriculture (CSA) has emerged as one important entry point in reducing the emission of greenhouse gases and building climate resilience while ensuring increases in agricultural productivity with ensuing implications on food and nutrition security. We examine the relationship between CSA, land productivity (yields), and food security using a survey of farm households in Ghana, Mali, and Nigeria. To understand the correlates of the adoption of these CSA practices as well as the association between CSA, yields, and food security, we use switching regressions that account for multiple endogenous treatments. We find a positive association between the adoption of CSA practices and yields. This increase in yields translate to food security as we observe a positive association between CSA and food consumption scores. Although we show modest associations between the independent use of CSA practices such as adopting climate-smart groundnut varieties, cereal-groundnut intercropping, and the use of organic fertilizers, we find that bundling these practices may lead to greater yield and food security gains. Under the different combinations, the use of climate-smart groundnut varieties exhibit the strongest association with yields and food security. We also estimate actual-counterfactual relationships where we show that the adoption of CSA practices is not only beneficial to CSA adopters but could potentially be beneficial to non-CSA adopters should they adopt. These results have implications for reaching some of the sustainable development targets, especially the twin goals of increasing agricultural productivity and maintaining environmental sustainability.  相似文献   

19.
This paper describes the possible developments in global energy use and production, land use, emissions and climate changes following the SSP1 storyline, a development consistent with the green growth (or sustainable development) paradigm (a more inclusive development respecting environmental boundaries). The results are based on the implementation using the IMAGE 3.0 integrated assessment model and are compared with a) other IMAGE implementations of the SSPs (SSP2 and SSP3) and b) the SSP1 implementation of other integrated assessment models. The results show that a combination of resource efficiency, preferences for sustainable production methods and investment in human development could lead to a strong transition towards a more renewable energy supply, less land use and lower anthropogenic greenhouse gas emissions in 2100 than in 2010, even in the absence of explicit climate policies. At the same time, climate policy would still be needed to reduce emissions further, in order to reduce the projected increase of global mean temperature from 3 °C (SSP1 reference scenario) to 2 or 1.5 °C (in line with current policy targets). The SSP1 storyline could be a basis for further discussions on how climate policy can be combined with achieving other societal goals.  相似文献   

20.
Humans utilise about 40% of the earth’s net primary production (NPP) but the products of this NPP are often managed by different sectors, with timber and forest products managed by the forestry sector and food and fibre products from croplands and grasslands managed by the agricultural sector. Other significant anthropogenic impacts on the global carbon cycle include human utilization of fossil fuels and impacts on less intensively managed systems such as peatlands, wetlands and permafrost. A great deal of knowledge, expertise and data is available within each sector. We describe the contribution of sectoral carbon budgets to our understanding of the global carbon cycle. Whilst many sectors exhibit similarities for carbon budgeting, some key differences arise due to differences in goods and services provided, ecology, management practices used, land-management personnel responsible, policies affecting land management, data types and availability, and the drivers of change. We review the methods and data sources available for assessing sectoral carbon budgets, and describe some of key data limitations and uncertainties for each sector in different regions of the world. We identify the main gaps in our knowledge/data, show that coverage is better for the developed world for most sectors, and suggest how sectoral carbon budgets could be improved in the future. Research priorities include the development of shared protocols through site networks, a move to full carbon accounting within sectors, and the assessment of full greenhouse gas budgets.  相似文献   

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