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91.
92.
Eric P Perramond 《Area》2007,39(4):499-507
Geographers working within political-cultural ecology and biogeography have often used a framework, or the general concept, of adaptation. The use of this blanket term, however, was and remains especially problematic for cultural-political ecology research, which tends to focus on a different scale of time–space analysis, while placing greater emphasis on the fine and coarse influences of political economy. To refine our understanding of daily activities that may lead towards adaptation, the concepts of 'tactics' and 'strategy' can bridge shorter-term phenomena that do not require the leap of scale implied by the loose use and implementation of the term adaptation.  相似文献   
93.
初论山东巨野煤矿开发的主要环境地质问题及防治对策   总被引:2,自引:0,他引:2  
山东巨野矿区是目前山东乃至华东地区最大的未开发整装优质煤田。规划的7对矿井已经开工建设,预计2008年建成投产。为进一步了解开发中可能产生的环境地质问题信息,增加编制矿区防灾减灾规划、制定生态环境恢复治理方案的参照依据。论文根据矿区的环境地质条件、煤田地质特征及开发规划工程特点,对煤炭资源开发过程中可能产生的地面塌陷、土地、土壤环境破坏与污染、地下水资源破坏和水质污染、矿井突水、煤矸石危害5种主要环境地质问题及其造成的影响进行了初步预测和分析。同时结合矿区开发进程提出了规划设计、建设开采和矿山闭坑3个阶段加强环境地质问题防治的对策与建议。  相似文献   
94.
We investigate how smallholder farmers at two sites in Kenya and Tanzania cope with climate stress and how constraints and opportunities shape variations in coping strategies between households and over time during a drought. On the basis of this analysis, we draw out implications for adaptation and adaptive policy. We find that households where an individual was able to specialize in one favoured activity, such as employment or charcoal burning, in the context of overall diversification by the household, were often less vulnerable than households where each individual is engaged in many activities at low intensity. Many households had limited access to the favoured coping options due to a lack of skill, labour and/or capital. This lack of access was compounded by social relations that led to exclusion of certain groups, especially women, from carrying out favoured activities with sufficient intensity. These households instead carried out a multitude of less favoured and frequently complementary activities, such as collecting indigenous fruit. While characterized by suitability to seasonal environmental variations and low demands on time and cash investments, these strategies often yielded marginal returns. Both the marginalization of local niche products and the commercialization of forest resources exemplify processes leading to differential vulnerability. We suggest that vulnerability can usefully be viewed in terms of the interaction of such processes, following the concept of locality. We argue that coping is a distinct component of vulnerability and that understanding the dynamism of coping and vulnerability is critical to developing adaptation measures that support people as active agents.  相似文献   
95.
This paper focuses on the Sub–Carpathian region which has traditionally maintained a large rural population and is today suffering acute economic and social stress. During the present transition phase the rural population is struggling to survive by combining elements of the modern and traditional economies and research has been undertaken to clarify a range of household strategies. After profiling the communes of the Buzau Carpathians the problem is tackled at two levels on the basis of questionnaire work carried out during 1998–1999. First there is a general overview to outline conditions in Patarlagele commune, including some local contrasts between settlements on main transport axis along the Buzau valley and those in the hills and side valleys. Second there is a consideration of in-depth profiles of specific households in villages in the wider area including Panatau as well as Patarlagele commune. It remains to be seen to what extent the district will be able to safeguard its social capital when growth resumes in large towns especially Brasov and Buzau with which Patarlagele has the best contacts. It is also an open question how far the remoter settlements will retain a viable population, assuming that the services remain relatively poor while disadvantage persists with regard to both employment opportunities and physical security. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
96.
In the marine environment, sessile invertebrates have developed an impressive array of mechanisms to avoid predation, bacterial exploitation, and epibiotic overgrowth. In the present study we investigated several defensive strategies adopted by six sabellids: the hard bottom species Sabella spallanzanii (Gmelin, 1791), Branchiomma luctuosum Grube, 1869, Branchiomma bairdi (McIntosh, 1885), and Sabellastarte spectabilis (Grube, 1878), and the soft bottom species Myxicola infundibulum (Renier, 1804), and Megalomma lanigera (Grube, 1846), which have different morphological characteristics and geographical distribution. We examined and compared some defensive features such as branchial crown toughness, tube structure and strength, amount of released mucus, and antibacterial lysozyme‐activity in the mucus. The investigated species utilize a combination of defence and deterrence strategies that seems to be related to the colonized habitat. Tube strength was, higher in the hard bottom species compared with the soft bottom ones, where the tubes are generally buried and protected within the sediment. Branchial crown appeared stronger and resistant in hard bottom species, except for S. spallanzanii, which is the species showing the strongest tube. Sabella spallanzanii, M. infundibulum and S. spectabilis secreted high amount of mucus with high lysozyme‐like activity. By contrast, B. luctuosum, B. bairdi, and M. lanigera produced low amounts of mucus exerting lower antibacterial activity.  相似文献   
97.
Taiwan has disadvantageous conditions for sediment-related disasters such as debris flows. The construction of engineering structures is an effective strategy for reducing debris flow disasters. However, it is impossible to construct engineering structures in all debris flow areas in a short period. Therefore, the government aims to gradually develop non-structural preventive strategies, including evacuation planning, debris flow disaster emergency action system, disaster resistant community program, recruitment of debris flow professional volunteers, debris flow warning systems, and land management strategies, to mitigate disasters and secure the safety of residents. This review describes the processes and effects of recent debris flow non-structural preventive strategies in Taiwan. The average number of casualties prior to the year 2000 was far higher than the corresponding number after 2000 because debris flow evacuation drills have been promoted since 2000 and the debris flow disaster emergency action system has been progressively improved since 2002. Furthermore, the changes in risks caused by debris flow disasters before and after the implementation of non-structural preventive strategies were used to explain the effectiveness of these strategies at the community level. The results showed that software-based non-structural preventive strategies can effectively reduce the casualties caused by debris flows at both the national and community levels.  相似文献   
98.
Grass seed farmers have burned their fields in Idaho and Washington State for decades. Field burning, however, creates small particulate matter air pollution, thus engendering a growing public backlash by the 1990s that manifested itself in new clean air advocacy groups. The new groups’ push for policy change eventually met with significant success in both cases. How did each set of advocates approach the challenge of policy change? More specifically, what kinds of policy venues did each group choose and why? This research uses the cases to explore and explain each clean air group's choices vis-à-vis hypotheses of venue choice. Three hypotheses are tested—Schattschneider's (1960 Schattschneider , E. E. 1960 . The semisovereign people . New York , NY : Holt, Rinehart, and Winston . [Google Scholar]) “expanded scope of conflict” thesis, ACF's (Sabatier and Jenkins-Smith 1999 Sabatier , P. , and H. Jenkins-Smith . 1999 . The advocacy coalition framework: An assessment . In Theories of the policy process , ed. P. A. Sabatier , 117166 . Boulder , CO : Westview Press . [Google Scholar]) contention that groups strategically apply their resources in order to increase the likelihood of achieving their primary goal(s), and Pralle's (2003 Pralle , S. B. 2003 . Venue shopping, political strategy, and policy change . J. Public Policy 23 : 233260 .[Crossref] [Google Scholar], 2010 Pralle , S. B. 2010 . Shopping around: Environmental organizations and the search for policy venues . In Advocacy organizations and collective action , ed. A. Prakash and M. K. Gugerty , 177203 . Cambridge , MA : Cambridge University Press .[Crossref] [Google Scholar]) thesis that internal group constraints deter groups from moving into new venues.  相似文献   
99.
在国家从严土地管理的新形势下,基层国土资源管理部门应科学地分析当前执法监察工作所面临的新形势,冷静地面对新问题,大胆地应对新挑战。要紧抓机遇,破解难题,就要从发挥主观能动性入手,大力推行治根治本之策,坚持"六个结合",重拳出击国土资源违法行为,担负起保护土地,促进地方经济发展的重任。  相似文献   
100.
The restriction of freshwater flow into estuaries, the presence of in-stream barriers and the occurrence of invasive fish species in these habitats are identified as major threats to these young estuary- and marine-spawned fish species. These aspects have been investigated using the distribution and abundance of young estuary- and marine-spawned fish species in the headwater environments of four permanently open estuaries of the Eastern Cape, South Africa. Fishes were collected twice per season over the 2009 and 2010 period, using mixed method sampling with seine net hauls and overnight fyke net deployments. Of the 74,751 fishes collected, 37,444 fishes, 18 families and 34 species were taken in fyke net catches, while 34,308 fishes, 21 families and 38 species were caught in seine nets. In the Great Fish, Kowie, Kariega and Sundays River systems, juveniles of estuarine residents dominated headwater catches, followed by juveniles of estuary-dependent marine species. The prevalence of larval and small juvenile stages of estuary- and marine-spawned fish species highlights the potential importance of these transitional areas for young fish.  相似文献   
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