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1.
The rapidly changing climate is posing growing threats for all species, but particularly for those already considered threatened. We reviewed 100 recovery plans for Australian terrestrial threatened species (50 fauna and 50 flora plans) written from 1997 to 2017. We recorded the number of plans that acknowledged climate change as a threat and of these how many proposed specific actions to ameliorate the threat. We classified these actions along a continuum from passive or incremental to active or interventionist. Overall, just under 60% of the sampled recovery plans listed climate change as a current or potential threat to the threatened taxa, and the likelihood of this acknowledgment increased over time. A far smaller proportion of the plans, however, identified specific actions associated with ameliorating climate risk (22%) and even fewer (9%) recommended any interventionist action in response to a climate-change-associated threat. Our results point to a disconnect between the knowledge generated on climate-change-related risk and potential adaptation strategies and the extent to which this knowledge has been incorporated into an important instrument of conservation action.  相似文献   
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Following the renewed effort at achieving a new green revolution for Africa, emphasis has been placed on modernizing smallholder agriculture through the deployment of improved inputs especially mechanized technologies. In Ghana, the government has in the last decade emphasized the provision of subsidized mechanized ploughing services to farmers alongside a rapidly growing private sector tractor service market. While mechanized technology adoption rates have increased rapidly, the deployment of these technologies has been without critical analysis of the impacts on production patterns and local agrarian systems. This paper examines the distributional impacts of agriculture mechanization on cropping patterns and farm sizes of smallholder farmers in northern Ghana using Geographic Information Systems (GIS) techniques, and semi-structured interviews with smallholder farmers (n=60). Specifically, comparative analysis of the field sizes and cropping patterns of participant farmers prior to and after the adoption of mechanized technologies was conducted. In-depth interviews were used to contextualize the experiences of smallholder farmers toward understanding how mechanization may be impacting traditional agriculture. Our findings reveal a mechanization paradox in which farm sizes are expanding, while cropping patterns are shifting away from traditional staple crops (pearl millet and sorghum bicolor) to market-oriented crops (maize, rice and groundnuts). This transition we argue, has adverse implications on the cultural dimension of food security, the organization of social life, and climate change adaptation. We recommend a retooling of the current agricultural policy focus to ensure context sensitivity for a more robust battle against food insecurity.  相似文献   
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This paper presents the technical aspects of a new methodology for assessing the susceptibility of society to drought. The methodology consists of a combination of inference modelling and fuzzy logic applications. Four steps are followed: (1) model input variables are selected—these variables reflect the main factors influencing susceptibility in a social group, population or region, (2) fuzzification—the uncertainties of the input variables are made explicit by representing them as ‘fuzzy membership functions’, (3) inference modelling—the input variables are used to construct a model made up of linguistic rules, and (4) defuzzification—results from the model in linguistic form are translated into numerical form, also through the use of fuzzy membership functions. The disadvantages and advantages of this methodology became apparent when it was applied to the assessment of susceptibility from three disciplinary perspectives: Disadvantages include the difficulty in validating results and the subjectivity involved with specifying fuzzy membership functions and the rules of the inference model. Advantages of the methodology are its transparency, because all model assumptions have to be made explicit in the form of inference rules; its flexibility, in that informal and expert knowledge can be incorporated through ‘fuzzy membership functions’ and through the rules in the inference model; and its versatility, since numerical data can be converted to linguistic statements and vice versa through the procedures of ‘fuzzification’ and ‘defuzzification’.  相似文献   
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Four introduced and one aboriginal species of the genus Pinus L. have been studied in the middle taiga subzone of southern Karelia. Significant interspecific differences in the dates of onset, cessation, and peak of the growth of shoots and needles have been revealed. It has been shown that their annual increment depends on the rate of growth, rather than on its duration. The dynamics of shoot and needle growth in introduced and aboriginal species, though largely similar, differ in some respects. These differences reflect species-specific responses to hydrothermal conditions in a certain growing season.  相似文献   
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In the diurnal lepidopteran fauna of the northern taiga subzone in the western Russian Plain, the species inhabiting primary biotopic complexes typical of this subzone currently account for slightly more than 60% of the total species richness and abundance. A large part of the fauna is represented by the species of more southern origin, whose expansion to the northern taiga was caused by anthropogenic transformation of landscapes between the 12th and 20th centuries and recent climate warming.  相似文献   
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INTRODUCTIONIn recent thirty years, due to the decreasing fertility andincreasing life expectancy, China's population is aging ata very rapid pace and the elderly population size is keepingon growing. During the dramatic aging progress, the oldestold group in China is catching our eyes. More and moreold people of China are becoming the oldest old. Theextremely old population (aged 80 and above) is increasingat 5.1% annually, while the old population above 65 isincreasing at 2.9%, and the…  相似文献   
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基于中国绿洲喜凉作物(chimonophilous crop)分布区39个站点1960~2016年逐日平均气温资料,运用线性趋势法、反距离加权插值(IDW)、Morlet小波、Mann-Kendall检验等方法,研究中国绿洲喜凉作物气候生长期的时空变化对变暖停滞的响应.结果表明:①变暖停滞期,中国绿洲喜凉作物气候生长期起、止日及生长期日数以-0.2d/10a、0.33d/10a、0.53d/10a的趋势变化,较1960~2016年起始日提前趋势减缓1.01d/10a,终止日推迟减缓1.28d/10a,生长期日数延长减缓2.3d/10a,对变暖停滞有响应.②中国绿洲喜凉作物气候生长期起始日对变暖停滞响应的站点有44%,终止日和生长期日数均为49%,主要分布在南疆、柴达木盆地和河西绿洲,其中河西绿洲对变暖停滞响应最明显,南疆次之,柴达木最小,而北疆绿洲不存在滞缓现象,显然空间差异明显.③M-K检验显示,中国绿洲喜凉作物气候生长期起、止日及生长期日数分别在2001年、1990年和1997年发生突变,起始日晚于变暖停滞起始年份,终止日和生长期日数早于变暖停滞起始年,且分绿洲生长期日数突变年与变暖停滞起始年相接近.④Morlet小波得出变暖停滞期其变化稳定存在2.4~4.3a的震荡周期,表明未来几年中国绿洲喜凉作物气候生长期仍持续延长.  相似文献   
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