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1.
The rangelands of the Mongolian Plateau are dynamic socio-environmental systems that are influenced by a complex network of drivers, including climate, social institutions, market forces, and national-scale policies affecting land access and management. The sustainability and resilience of rangelands in this region depend on the ability of residents and policy makers to quickly respond by adapting livelihoods and land uses to changes in environmental and socio-economic conditions, but the responses of the system to these changes are often non-linear and difficult to predict. We developed a system dynamics model to understand how the human, natural, and land-use processes in the Mongolian rangeland ecosystem interact to produce dynamic outcomes in both grassland productivity and livestock populations. We developed two separate models based on a common integrative framework for two case study areas: Suhkbaatar Aimag in Mongolia and Xilingol League in Inner Mongolia. We used future scenarios for each region generated with stakeholder input to forecast trends in grassland area, livestock numbers, and biomass under alternative climate, socioeconomic, and land-use futures. By incorporating stakeholder-developed scenarios, we were able to explore future scenarios tailored to the particular questions and concerns relevant to the individual study areas. We find that while there are many similarities in the factors driving system dynamics in the two countries, the trajectories of key grassland resources are quite different, both between the two study regions and across the individual scenarios. Environmental policies play a key role in Xilingol, while economic development is a key driver in Sukhbaatar. Urbanization dynamics will be a major influence on the availability of grassland resources in the future.  相似文献   

2.
The realisation that runoff and soil erosion was a problem came late to Britain and policies to tackle the problem have evolved slowly and may well have a taken a different route to that in other countries. The perception of soil erosion and runoff in Britain by three interest groups (researchers, policy makers and farmers) has changed over time since the 1940s. Prior to 1970 none of the groups considered erosion and runoff were problems. From then to 1985 researchers found that erosion was widespread. Between 1985 and 2005 researchers not only confirmed that erosion was a problem, but that runoff and its impacts (muddy floods and pollution of water courses by sediment, phosphate and pesticides) were also problems. These widespread and costly economic and environmental impacts led policy makers to tackle the problems of erosion and runoff. From 2005 farmers have had to keep their land in ‘Good Agricultural and Environmental Condition’ by, amongst other things, attempting to curtail erosion and runoff, to comply with regulation in order to receive subsidy. Policy change was also stimulated by changes in the European Union's Common Agricultural Policy and the passing by the EU of the ‘Water Framework Directive’. Policy, if it is to be evidence based, will always lag behind research. There is a continuing need for field-based monitoring to assess if regulation is working, to ensure compliance, and as a basis for future policy.  相似文献   

3.
As nations develop policies for low-carbon transitions, conflicts with existing policies and planning tools are leading to competing demands for land and other resources. This raises fundamental questions over how multiple demands can best be managed. Taking the UK as an empirical example, this paper critiques current policies and practices to explore the interdependencies at the water-energy-food nexus. It considers how current land uses and related policies affect the UK’s resilience to climate change, setting out an agenda for research and practice relevant to stakeholders in land-use management, policy and modelling. Despite recent progress in recognising such nexus challenges, most UK land-related policies and associated science continue to be compartmentalised by both scale and sector and seldom acknowledge nexus interconnections. On a temporal level, the absence of an over-arching strategy leaves inter-generational trade-offs poorly considered. Given the system lock-in and the lengthy policy-making process, it is essential to develop alternative ways of providing dynamic, flexible, practical and scientifically robust decision support for policy-makers. A range of ecosystem services need to be valued and integrated into a resilient land-use strategy, including the introduction of non-monetary, physical-unit constraints on the use of particular services.  相似文献   

4.
This article re-conceptualizes Climate Policy Integration (CPI) in the land use sector to highlight the need to assess the level of integration of mitigation and adaptation objectives and policies to minimize trade-offs and to exploit synergies. It suggests that effective CPI in the land use sector requires i) internal climate policy coherence between mitigation and adaptation objectives and policies; ii) external climate policy coherence between climate change and development objectives; iii) vertical policy integration to mainstream climate change into sectoral policies and; iv) horizontal policy integration by overarching governance structures for cross-sectoral coordination. This framework is used to examine CPI in the land use sector of Indonesia. The findings indicate that adaptation actors and policies are the main advocates of internal policy coherence. External policy coherence between mitigation and development planning is called for, but remains to be operationalized. Bureaucratic politics has in turn undermined vertical and horizontal policy integration. Under these circumstances it is unlikely that the Indonesian bureaucracy can deliver strong coordinated action addressing climate change in the land use sector, unless sectoral ministries internalize a strong mandate on internal and external climate policy coherence and find ways to coordinate policy action effectively.  相似文献   

5.
This study uses an integrative approach to study the water-quality impacts of future global climate and land-use changes. In this study, changing land-use types was used as a mitigation strategy to reduce the adverse impacts of global climate change on water resources. The climate scenarios were based on projections made by the Intergovernmental Panel on Climate Change (IPCC) and the United Kingdom Hadley Centre's climate model (HadCM2). The Thornthwaite water-balance model was coupled with a land-use model (L-THIA) to investigate the hydrologic effects of future climate and land-use changes in the Ohio River Basin. The land-use model is based on the Soil Conservation Service's curve-number method. It uses the curve number, an index of land use and soil type, to calculate runoff volume and depth. The ArcView programming language, Avenue, was used to integrate the two models into a geographic information system (GIS). An output of the water-balance model, daily precipitation values adjusted for potential evapotranspiration, served as one of the inputs into the land-use model. Two watersheds were used in the present study: one containing the city of Cincinnati on the main stem of the Ohio River, and one containing the city of Columbus on a tributary of the Ohio River. These cities represent two major metropolitan areas in the Ohio River Basin with different land uses experiencing different rates of population growth. The projected hypothetical land-use changes were based on linear extrapolations of current population data. Results of the analyses indicate that conversion from agricultural land use to low-density residential land use may decrease the amount of surface runoff. The land-use practices which generate the least amount of runoff are forest, low-density residential, and agriculture; whereas high-density residential and commercial land-use types produce the highest runoff. The hydrologic soil type present was also an important factor in determining the amount of runoff and non-point-source pollution. A runoff-depth matrix and total nitrogen matrix were created for Cincinnati and Columbus to describe possible land-use mitigation measures in response to global climate change. The differences in Cincinnati and Columbus were due to differences in geographic location, air temperature, and total runoff. The results of this study may be useful to planners and policy makers for defining the possible impacts of future global climate and land-use changes on water resources.  相似文献   

6.
In this paper we show how ideas from a longstanding but little recognised literature on adaptive governance can be used to rethink the way science supports Australian drought policy. We compare and contrast alternative ways of using science to support policy in order to critique traditional commentary on Australian drought policy. We find that criticism from narrow disciplinary and institutional perspectives has provided few practical options for policy makers managing these complex and interacting goals. In contrast, ideas from a longstanding but little recognised literature on adaptive governance have potential to create innovative policy options for addressing the multiple interacting goals of Australian drought policy.From an adaptive governance perspective, the deep concern held by Australian society for rural communities affected by drought can be viewed as a common property resource that can be sustainably managed by governments in cooperation with rural communities. Managing drought assistance as a common property resource can be facilitated through nested and polycentric systems of governance similar to those that have already evolved in other arenas of natural resource management in Australia, such as Landcare groups and Catchment Management Authorities. Essential to delivering these options is the creation of flexible, regionally distributed scientific support for drought policy capable of integrating local knowledge and informing the livelihood outcomes of critical importance to governments and rural communities.  相似文献   

7.
土地利用研究是国际地圈生物圈计划和国际全球环境变化人文因素计划研究中的重要内 容;分析不同国家土地利用研究动态,对于识别土地利用研究的国际差异具有积极意义。本文基 于科学引文索引数据库和社会科学引文索引数据库,通过文献分析的方法,对比了全球和世界主 要国家土地利用研究的差异。研究结果表明,在过去近10 年的时间里,世界土地利用取得了快 速发展;美国、加拿大、日本、英国、挪威、澳大利亚、德国、瑞士、法国和比利时等国家的科 学家在开展本国土地利用研究的同时,也开展了许多中国土地利用的研究;但是,与此相对应, 中国科学家在开展土地利用研究过程中,注重对国内土地利用的研究,但是对其他国家土地利用 的研究明显相对不足。在未来土地利用的研究中,中国科学家不仅需要进一步加强国内土地利用 问题的研究,更需要拓展国际化视野,加强全球和其他国家土地利用的研究,重点开展全球土地 利用数据库的建设、全球土地利用变化与粮食安全、全球土地利用变化与碳排放、国际河流土地 利用变化与生态安全、重点区域或国家的土地利用对比研究等方面的工作,以期在推进我国土地 利用研究水平提升的同时,更好地服务于国家国际化战略的迫切需求。  相似文献   

8.
Water quality modelling is an effective tool to investigate, describe and predict the ecological state of an aquatic ecosystem. Various environmental variables may simultaneously affect water quality. Appropriate selection of a limited number of key-variables facilitates cost-effective management of water resources. This paper aims to determine (and analyse the effect of) the major environmental variables predicting ecological water quality through the application of fuzzy models. In this study, a fuzzy logic methodology, previously applied to predict species distributions, was extended to model environmental effects on a whole community. In a second step, the developed models were applied in a more general water management context to support decision and policy making. A hill-climbing optimisation algorithm was applied to relate ecological water quality and environmental variables to the community indicator. The optimal model was selected based on the predictive performance (Cohen’s Kappa), ecological relevance and model’s interpretability. Moreover, a sensitivity analysis was performed as an extra element to analyse and evaluate the optimal model. The optimal model included the variables land use, chlorophyll and flow velocity. The variable selection method and sensitivity analysis indicated that land use influences ecological water quality the most and that it affects the effect of other variables on water quality to a high extent. The model outcome can support spatial planning related to land use in river basins and policy making related to flows and water quality standards. Fuzzy models are transparent to a wide range of users and therefore may stimulate communication between modellers, river managers, policy makers and stakeholders.  相似文献   

9.
This article applies a ‘knowledge brokering’ approach to contextualise the development of an integrated computer modelling tool into the real world policy context of adaptation of agriculture to climate change at the EU level. In particular, the article tests a number of knowledge brokering strategies described and theorised in the literature, but seldom empirically tested. The article finds that while the policy context can be used to identify a theoretically informed knowledge brokering strategy, in practice a strategy's ‘success’ is more informed by practical considerations, such as whether the tool development process is knowledge or demand driven. In addition, in practice the knowledge brokering process is found to be dynamic and messy, which is not always apparent in the literature. The article goes on to question the perception that there is always a need (or a desire) to bridge the gap between researchers and policy makers in the tool development process. Rather than a problem of design and communication, the science policy interface may be characterised more by a high level of competition between researchers and research organisations to have their tool legitimised by its use in the policy making process.  相似文献   

10.
PRA和GIS在小尺度土地利用变化研究中的应用   总被引:11,自引:1,他引:10  
论文借助PRA,结合实地测量和GIS,以宁夏南部山区的上黄村为例对小尺度区域的土地利用变化进行了初步研究。重建和恢复了其25年来各时期的土地利用过程,绘制了上黄试区不同时期的土地利用空间变化图,并对其土地利用的数量及空间变化进行了分析。结果表明:在研究期内,从数量上看,耕地和林地变化最为显著,年变化率分别达到了8.0%和9.2%;从空间分布变化来看,主要表现为耕地向林地、草地及园地转变。  相似文献   

11.
基于“三生”适宜性的县域土地利用冲突识别与分析   总被引:1,自引:0,他引:1  
精准识别潜在土地利用冲突有利于预警权衡和协调冲突用地,有利于科学进行国土空间规划。以“三调”修正数据为基础,基于生产、生活、生态视角,构建高植被覆盖率县域生产、生活、生态即“三生”适宜性评价模型与土地利用冲突识别矩阵,并选取横峰县进行实证分析。结果表明:(1)横峰县“三生”适宜性用地的空间分布与面积构成差异显著,且存在明显的空间叠加特征,暗示着研究区土地利用存在冲突;(2)从潜在冲突识别的结果来看,土地利用适宜区、冲突激烈区、冲突中度区、冲突一般区及冲突微弱区面积占比分别为64.02%、9.66%、17.19%、1.66%、7.48%;(3)各个冲突类型区空间分布、表现形式的差异性决定了冲突和解的对策也需因地制宜。研究结果可为相关及类似县域的国土空间规划提供理论参考。  相似文献   

12.
谭淑豪  刘青  张清勇 《自然资源学报》2021,36(12):3131-3143
关注以稻虾共作为代表的稻田综合种养土地利用新型模式,基于在湖北省潜江市和荆州市的实地调研数据,运用非期望产出的SBM模型和投入导向DEA方法,测算和比较了稻虾共作户和水稻单作户土地利用的生态—经济效果。研究发现:与水稻单作相比,稻虾共作能够改善土地利用的生态—经济效果;但调研区一半以上的共作农户仍然延续着传统粗放的生产模式,生产中存在严重的过量投入,阻碍了其土地利用生态—经济效果的进一步优化。此外,若忽略环境污染,只考虑经济效果,将导致稻虾共作的土地利用效率被高估45.28%。目前,稻虾共作提高土地利用效率的功能未能充分发挥,亟需把环境影响纳入土地利用效率评估中,贯彻“双水双绿”的发展理念,引导农户合理安排各项生产投入,切实优化稻虾共作的生态—经济效果,促进土地可持续利用。  相似文献   

13.
东江下游河网区土地利用变化及其对水体的生态影响   总被引:3,自引:1,他引:2  
论文以东莞市为研究区域,基于1990、2000、2009年3期遥感影像,采用土地利用变化速率、土地利用转移矩阵及景观指标,分析了近20 a东莞市土地利用变化过程及其对水体的生态效应。研究结果表明:①近20 a东莞市土地利用结构由农业用地、林地为主向城市建设用地为主迅速转变,耕地、园地、林地比例由1990年的23.56%、13.39%和28.73%下降为2009年的11.35%、3.26%和17.39%,与此同时建设用地面积比例则由20.21%增加为53.62%,此外,2000—2009年土地利用变化程度较1990—2000年更为剧烈;②东莞市农业用地面积逐年降低,单位面积化肥施用量减少58.30%,单位面积农药施用减少32.35%,表明农业面源污染在过去一段时间内具有减弱趋势,与此同时城镇建设用地下垫面增加导致的城市非点源污染威胁则逐渐增强,这一情形将随着城市化用地的继续扩展和水体总面积的减少而愈加严重;③东莞市水体景观优势程度逐渐下降,水体受人为干扰强烈。水库、河流缓冲带内建设用地比例明显增加,河道被人工化、渠道化程度增强。综合以上研究结果,东莞在城市化建设中应加强水资源的保护和管理;水污染防治中,在治理点源污染的基础上,加强城市下垫面非点源污染的防控。  相似文献   

14.
Urban planning has the potential to be a powerful tool for facilitating efficient and equitable adaptation to climate change-related coastal hazards (‘coastal climate hazards’). However, if urban planning measures are poorly designed or implemented, it can increase costs and vulnerability, and unfairly affect the interests of particular groups. Through a case study on the coastal climate hazard planning framework in Victoria, Australia, this paper aims to illustrate how urban planning measures can lead to maladaptation and draw lessons for the future design and implementation of planning responses. Five main policy lessons are drawn from the case study. First, planning frameworks should encourage the adoption of robust approaches that are as insensitive to the uncertainties associated with coastal climate hazards as possible. Secondly, policy makers need to be mindful of the opportunity costs and equity implications of planning responses. Thirdly, to be sustainable, planning responses must be robust to social and political factors, something that can be achieved through the use of flexible approaches that allow continued use and development of land but on conditions that protect the interests of governments and communities. Fourthly, policy makers need to be mindful of transaction costs. Finally, when devolving planning responsibilities to lower levels of government, policy makers need to ensure that the objectives of planning frameworks are clear, there is minimal ambiguity in decision guidelines, and that the resourcing and capacity constraints of planning bodies are appropriately considered.  相似文献   

15.
我国当前城乡建设用地置换的实践探索及问题剖析   总被引:6,自引:1,他引:5  
当前我国城乡建设用地利用存在着城市建设用地指标紧缺、农村建设用地低效利用和城乡建设用地"双增"大量侵占耕地等问题。城乡建设用地增减挂钩政策推动下的城乡建设用地置换有望成为破解该问题的综合途径。2004年开始,伴随相关政策陆续出台,城乡建设用地置换实践在多个省市试点推进,其中江苏省万顷良田建设工程、天津市宅基地换房、山东省农村社区化、重庆市地票交易市场的实践较为典型。基于上述典型案例和系统要素分析,总结了实践的问题、根源与演进,认为目前系统中的要素与相应的操作环节中存在问题隐患且部分问题表现突出;实践中主要以涉及"非自愿"置换、补偿与保障不足、生产生活方式改变等的农民利益受损问题较为突出;问题的根源集中在三个方面,即国家层面的约束性的法律、法规、政策尚不健全,地方政府操作不合理和缺乏科学研究支撑。今后的实践中,应该建立统一的城乡土地市场并逐步完善政府主导下的城乡土地市场运行机制,建立科学合理的征地补偿机制,深入开展相关科学研究,遵循集约型用地增长模式,同小城镇建设紧密结合,注重保护村落景观风貌。  相似文献   

16.
CLUE-S模型及其在奈曼旗土地利用时空动态变化模拟中的应用   总被引:57,自引:1,他引:56  
在对目前常用的土地利用变化模型进行调研的基础上,认为CLUE-S模型是众多模型中适用于区域土地利用变化研究的一种较好的模型;它是根据系统论的观点,在深刻理解土地利用系统内土地利用变化特征(包括关联性、竞争性、稳定性以及等级性等)的基础上构建而成,具有同步模拟不同土地利用变化的能力。论文以奈曼旗为例,根据1985年的空间图形数据,结合道路、居民点、城镇、水域的分布、以及地形和土壤等驱动因素,对其2000年的土地利用变化格局进行模拟;并用2000年的土地利用现状图对模拟结果进行检验。结果显示,在基本单元(500m×500m栅格)的水平上,模拟的正确率为85%,Kappa指数值是0.80。说明CLUE-S模型具有成功模拟区域土地利用时空动态变化的能力,是值得向国内同行推荐的一种较好的LUCC模型。  相似文献   

17.
The Netherlands has attempted to follow EU guidelines in developing national policies to reduce pollution of groundwater by nitrates originating from (over) fertilized agricultural land. The EU has not been satisfied with these policies and this is resulting in legal conflicts. National policies have focused on nitrogen budgeting and on fertilization rates, over-simplifying the crucial role of soils during the leaching of nitrates to groundwater. As an alternative, a dynamic approach using simulation modeling is introduced as is illustrated for a study area in the Netherlands. A number of considerations for future policy directions are suggested, including requirements for research: (i) promotion of research aimed at improving and maintaining nutrient use efficiency at farm level; (ii) promotion of joint learning experiences between farmers and researchers, where farmers’ organizations could act as “research consortia”; (iii) emphasis on site and time specific management (precision agriculture) in policy development, and provision of site-specific advice via modern information and communication technologies; (iv) clearer guidelines for groundwater monitoring procedures, including additional monitoring at greater depths and consideration of groundwater quality from an appropriate regional perspective; (v) groundwater monitoring should take place at locations selected according to specific hydro-geological characteristics, rather than being executed at random and (vi) clear goals that are defined within existing and future policies at EU and international level, should allow for regional differentiation in indicators; these being the outcome of negotiations between farmers or their representatives, policy makers and researchers.  相似文献   

18.
Theory suggests that the influence of science on policy will be greater when scientific discourse is aligned with the language and meaning of wider social concerns. Seeking to assess whether scientists may be guided by such propositions in a controversial environmental policy arena, we examine the language and content of public-facing, UK scientific research grant abstracts on biofuels for the period 2007–2011, comparing these to stakeholder position statements and newspaper articles of the same period. We find that UK scientists have indeed broadly reflected societal concerns about biofuels during this period. However we also find that both science and society have paid less attention to procedural issues. We comment on the implications of the findings for the role of science in environmental policy development.  相似文献   

19.
为了研究土地利用规划对建设用地扩张的管控效果,论文从规划目标一致性与实施有效性两个视角出发构建概念模型,选择GIS空间分析方法与Logistic计量模型作为技术支撑,对江苏通州进行案例研究。结果表明:1基于一致性视角,从空间规模与空间结构控制效果来看,通州土地利用总体规划在2002—2010年间对建设用地扩张的管控效果较差,对具体地类而言,新增城镇工矿用地的管控效果要优于农村居民点用地;2基于有效性视角,规划对建设用地扩张具有显著影响,规划确定的建设预留区对建设用地扩张起到了明显的空间引导作用,但与预期相反,规划基本农田保护区却未发挥出应有的约束作用;3综合来看,规划实施的一致性较差,且规划管控仅在一定程度上有效,处于不完全理想的状态;4对比可知,发展到一定阶段之后,空间区位变量对建设用地扩张的驱动作用会相对更强,意味着集聚发展可能成为必然,有必要强化规划实施的空间管控效果。该模型能够较好地评价土地利用规划对建设用地扩张的管控效果,可为完善规划实施评价的理论与技术方法提供参考。  相似文献   

20.
Effective risk management within environmental policy making requires knowledge on natural, economic and social systems to be integrated; knowledge characterised by complexity, uncertainty and ambiguity. We describe a case study in a (UK) central government department exploring how risk governance supports and hinders this challenging integration of knowledge. Forty-five semi-structured interviews were completed over a two year period. We found that lateral knowledge transfer between teams working on different policy areas was widely viewed as a key source of knowledge. However, the process of lateral knowledge transfer was predominantly informal and unsupported by risk governance structures. We argue this made decision quality vulnerable to a loss of knowledge through staff turnover, and time and resource pressures. Our conclusion is that the predominant form of risk governance framework, with its focus on centralised decision-making and vertical knowledge transfer is insufficient to support risk-based, environmental policy making. We discuss how risk governance can better support environmental policy makers through systematic knowledge management practices.  相似文献   

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