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111.
Today “rural diversification” is high on the agenda in rural development. This article analyses rural diversification under conditions of post-socialist economic transition using case areas in Latvia and Estonia. The study shows that transition from centrally planned economy to market economy has had an enormous impact in the rural areas. Agricultural production and employment has decreased dramatically and rural unemployment is high. The conditions for rural diversification the first years after independence depended a lot on the local presence of non-farm activities before the split up of collective farming, in both production facilities but also in the skills and relations people had. Since independence, markets for traditional rural services and products have decreased. The extent to which local businesses find markets outside the local area and people have been able to integrate into the new labour market of service and construction jobs often in urban areas are essential for the diversification of the rural economy. Most rural inhabitants only have skills in large-scale agriculture and limited contacts to outside the local area which makes exploiting new opportunities difficult. The local capacity for withholding, developing and inducing new activities is weak. The challenge for rural development policy is to extend the possibilities of the rural inhabitants to exploit new opportunities.  相似文献   
112.
Spheroidal carbonaceous fly-ash particles (SCPs) are produced by the high temperature combustion of fossil-fuels such as coal and oil. They are not produced by any natural processes and therefore are unambiguous indicators of atmospheric deposition from power generation and other industrial sources. In lake sediments, SCP concentration profiles are robust, replicable and often regionally characteristic such that the main profile features can be used for sediment dating. Previous work in the UK provided dates for the three main SCP profile features for Scotland, North Wales and Northern Ireland and also highlighted the lack of information for the rest of the UK. In this study, archived SCP data and new SCP concentration profiles were compiled from 80 radionuclide-dated sediment cores from across the whole of the UK in order to determine the regional coherence of temporal trends. Using SCP cumulative percentage profiles, with the SCP concentration peak set as 100%, dates for each 10% were produced for each core. Comparing these dates, eight distinct regions were found within the UK and dated cumulative profiles, with errors, were determined for each. Despite this regionality, the whole of the UK showed the same date for the start of the record (1850±25 years) and for the 40- and 50% (1940±15 and 1955±15, respectively). The national coherence of the former is thought to be due to the large confidence limits in the radionuclide dates for this period, whilst the latter is thought to be due to the impact from the major increase in electricity demand following the Second World War and the widespread introduction and use of cheap fuel-oil. Since the 1960s the trend has been one of increasing regionalisation resulting from the introduction of particle arrestor technology, the decline of heavy industry, the move to fewer and larger sources, particularly power stations, and an increase in accuracy for the dates of recent horizons. Regional trends are seen to compare well with industrial development in the UK and in some western areas influenced by emissions from Ireland. Areas of uncertainty remain in South Wales and the northern isles. A cumulative percentile was also calculated for each region for 1963 in order that this can be compared with the 241Am and 137Cs peaks.  相似文献   
113.
K–Ar and 40Ar/39Ar ages have been measured on nine mafic volcanic rocks younger than 1 myr from the Snake River Plain (Idaho), Mount Adams (Washington), and Crater Lake (Oregon). The K–Ar ages were calculated from Ar measurements made by isotope dilution and K2O measurements by flame photometry. The 40Ar/39Ar ages are incremental-heating experiments using a low-blank resistance-heated furnace. The results indicate that high-quality ages can be measured on young, mafic volcanic rocks using either the K–Ar or the 40Ar/39Ar technique. The precision of an 40Ar/39Ar plateau age generally is better than the precision of a K–Ar age because the plateau age is calculated by pooling the ages of several gas increments. The precision of a plateau age generally is better than the precision of an isotope correlation (isochron) age for the same sample. For one sample the intercept of the isochron yielded an 40Ar/36Ar value significantly different from the atmospheric value of 295.5. Recalculation of increment ages using the isochron intercept for the composition of nonradiogenic Ar in the sample resulted in much better agreement of ages for this sample. The results of this study also indicate that, given suitable material and modern equipment, precise K–Ar and 40Ar/39Ar ages can be measured on volcanic rocks as young as the latest Pleistocene, and perhaps even the Holocene.  相似文献   
114.
This paper traces how scientific research on wheat (Triticum) worked to establish Palestine as a region sought for colonization. Recent work in geography has refined our understanding of agricultural expansion as an outcome of colonization, however, this work leaves the place-making capacity of agricultural research largely unexplored. My claim is that rather than a byproduct of colonization, wheat research served to remake Palestine as a biophysical region in need of improvement and colonization. I show how a shift in the plant sciences from research in taxonomy to plant breeding corresponded to an agro-climatic shift on Palestine from an undesirable, arid region to a promising dryland agricultural region. In this way, wheat research drew Palestine and the United States into a wider effort to transform arid areas into agricultural drylands. Drawing on a previously unexplored episode of technical cooperation between researchers in the United States and Palestine, I argue that we must examine how wildness, native-ness, and agro-climatic suitability are scientifically constituted within and not apart from colonial conquest. In doing so, the paper calls for reconsideration within geography and political ecology of the place-making relationship between colonization and scientific practice.  相似文献   
115.
This paper presents results from a field experiment of running a prediction market for international climate negotiations. We draw upon our experience of running the Copenhagen Prediction Market during the Copenhagen Climate Summit in December 2009. The Copenhagen Prediction Market consisted of 17 different markets, where participants could trade in shares predicting, amongst others, reduction targets for various countries, the long-term stabilisation goal or the level of funding from developed countries to developing nations for mitigation and adaptation actions. We show that this novel application of prediction markets to climate negotiations is distinct from more traditional applications and, in many ways, more challenging. We discuss our experiences in designing and setting up the market and interpreting its results. In particular, it is crucial to be able to define the outcome of a climate conference in the face of often ambiguous final communications in order to make the prediction market robust and to find benchmarks to compare prediction market performance against.  相似文献   
116.
‘Offshore CO2 storage’ refers to the injection of liquefied CO2 into deep geological formations beneath the seabed (e.g. depleted oil and gas reservoirs, and saline aquifers) for the purpose of storing it there on a permanent basis. The storage in this manner of captured CO2 emissions from industrial installations and power plants has attracted considerable scientific and technical interest as a potential mitigation response to climate change. A key issue facing policymakers in several countries is how to reconcile policy commitments to develop offshore CO2 storage with other competing – and potentially conflicting – uses of the marine environment. With a view to informing policy responses to this issue, this paper presents a case study of legal and policy frameworks concerning offshore CO2 storage in United Kingdom. The paper maps key design features of the United Kingdom׳s framework for marine permitting and planning, appraising the extent to which they enable orderly development of offshore CO2 storage in a manner consistent with relevant high-level policy objectives.  相似文献   
117.
2010年5月英国保守党和自由民主党组成联合政府执政,其气候变化政策也相应发生了一些变化。根据7月27日英国政府公布的首份《年度能源报告》、卡梅伦首相的文章及能源与气候变化大臣休恩的演讲,可粗线条勾勒出其气候变化政策的一些基本走向。在国际框架上,新政府把积极推动国际减排,维护英国低碳技术的国际商业利益作为其未来施政的一个重要方向,更加坚持发展中国家承担减排任务及"三可"机制。在英国本土,气候变化的重点则由原来的"减排"转而强调"适应"。英国新政府十分重视与中国在低碳领域的合作。对于中国而言,机遇与挑战并存,需要尽快尽早制定国家级的低碳发展战略。  相似文献   
118.
The abundance of some marine fish species are correlated to the abundance of habitat-forming benthic organisms such as sponges and corals. A concern for fisheries management agencies is the recovery of these benthic invertebrates from removal or mortality from bottom trawling and other commercial fisheries activities. Using a logistic model, observations of available substrate and data from bottom trawl surveys of the Aleutian Islands, Alaska, we estimated recovery rates of sponges and corals following removal. The model predicted the observed sponge and coral catch in bottom trawl surveys relatively accurately (R2=0.38 and 0.46). For sponges, the results show that intrinsic growth rates were slow (r=0.107 yr−1). Results show that intrinsic growth rates of corals were also slow (r=0.062 yr−1). The best models for corals and sponges were models that did not include the impacts of commercial fishing removals. Subsequent recovery times for both taxa were also predicted to be slow. Mortality of 67% of the initial sponge biomass would recover to 80% of the original biomass after 20 years, while mortality of 67% of the coral biomass would recover to 80% of the original biomass after 34 years. The modeled recovery times were consistent with previous studies in estimating that recovery times were of the order of decades, however improved data from directed studies would no doubt improve parameter estimates and reduce the uncertainty in the model results. Given their role as a major ecosystem component and potential habitat for marine fish, damage and removal of sponges and corals must be considered when estimating the impacts of commercial bottom trawling on the seafloor.  相似文献   
119.
Conventional sectoral management and piecemeal governance are considered less and less appropriate in pursuit of sustainable development. Ecosystem based marine spatial management (EB-MSM) is an approach that recognizes the full array of interactions within an ecosystem, including human uses, rather than considering single issues, species, or ecosystem services in isolation. Marine spatial planning and ocean zoning are emerging concepts that can support EB-MSM. EB-MSM is driven by high-level goals that managers aim to achieve through the implementation of measures. High-level goals and objectives need to be translated into more operational objectives before specific targets, limits and measures can be elaborated.Monitoring, evaluation and adaptation are necessary to ensure that marine management measures are both effective and efficient. Solid monitoring frameworks are the foundation of adaptive management, as they provide the necessary information to evaluate performance and the effectiveness of management actions. Marine protected areas (MPAs) - possibly set up in networks - constitute a key component in EB-MSM policies and practises and have been applied as a cornerstone in conservation of marine biodiversity, management of fish populations, development of coastal tourism, etc. Moreover, MPA experiences have provided methods and concepts (such as zoning) to a wider EB-MSM context. The assignment of values to biophysical features of the marine environment allows the direct assessment of related management choices and may assist EB-MSM.A range of monetary valuation techniques have been proposed to reduce attributes of goods and services to a single metric. However, in the marine environment such an approach is often over simplistic, and thus less reductive techniques may be necessary. Rather than producing a single metric, the results of non-monetary assessments guide policy allowing weight to be given as necessary to potential areas of conflict and consensus.Strategies to take into account climate change effects and geohazard risks in EB-MSM have been applied or proposed worldwide. EB-MSM regimes must be alert to such risks and flexible to account for changes.  相似文献   
120.
《联合国气候变化框架公约》(简称《公约》)第25次缔约方会议取得了一定进展,但未能就各方最为关注的《巴黎协定》第六条市场机制实施细则达成一致。会议成果平淡主要有4个原因:第一,过度强调提高各方减排目标力度而未能聚焦《巴黎协定》第六条相关谈判;第二,主席国和部分缔约方急切将各方尚未形成政治共识的提高承诺力度问题引入谈判进程,破坏了谈判氛围;第三,各个议题推进不平衡;第四,发达国家企图逃避责任,促使发展中国家更加团结并形成对立。展望2020年的全球气候多边进程形势,《巴黎协定》第六条相关谈判将继续作为重点,提高力度也将成为讨论主题,但片面强调1.5℃目标可能引发重谈《巴黎协定》风险,同时发达国家背弃《公约》、转嫁责任意图明显。全球气候治理应聚焦落实承诺的力度,并平行推进《公约》及其《巴黎协定》的实施。  相似文献   
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