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161.
The karst lands of southern China 总被引:1,自引:0,他引:1
Tony Waltham 《Geology Today》2009,25(6):232-238
162.
Community mobilisation for improved livelihoods through tree crop management in Niger 总被引:1,自引:0,他引:1
Effective natural resource management requires interrelated technical practices and social arrangements that are appropriate
to a region’s biophysical characteristics and that address protection and sustainable management of resources. This is illustrated
from our experience in the Republic of Niger, West Africa. In 1980 barren plains, infertile soils, drought, dust storms, severe
fodder shortages, and agricultural pest outbreaks were normal occurrences in Niger’s rural regions. In general, despite large
investments of time and funding, conventional reforestation efforts had little impact. However by 2008 over five million hectares
of once barren land had been transformed through wide adoption of an agroforestry method known as ‘Farmer Managed Natural
Regeneration’ (FMNR), introduced in 1983. In the Aguie Department, the practice of FMNR was formalized through the Desert
Community Initiative (DCI), addressing interrelated technical and social issues in resource management. New governance structures,
which include marginalized groups, implement monitoring and enforcement systems enabling communities to manage land and regenerating
trees. These, together with technical solutions that build on local knowledge and skills and use previously undervalued indigenous
tree species, have generated a sustainable fuel-wood market for the first time. Increased linkage and compatibility between
institutions at local and national levels and strengthened social capital have been crucial to these impacts. Food security
and community resilience to drought have been markedly enhanced and local incomes have increased. The experience provides
important lessons for approaches to addressing environmental degradation and poverty in other semi arid areas and facilitating
the spread and adoption of new agroforestry systems. 相似文献
163.
We present a study that reconstructs the ancient courses of the Euphrates in part of the Mesopotamian floodplain west and southwest of the ancient site of Babylon. The focus is on tracing paleochannel courses, determining when these paleochannels were active, and understanding the patterns of avulsion. The research was carried out using a combination of geological, geomorphological, remote sensing, historical, and archaeological approaches. Fieldwork included “ground truthing” of the remote sensing work, manually drilling boreholes (up to 7 m in depth), sedimentary and geomorphological documentation and sample collection for radiocarbon dating. As a result, five main courses of the Euphrates in five different periods have been mapped in this area, including four previously unidentified and/or unlocated migrations that linked the different periods. The main courses are the Purattum Course (before 3100–1000 BC), the Arahtum Course (1000–125 BC), the Sura Course (125 BC to AD 1258), the Hilla Course (13th to 19th century AD), and the Hindiya Course (19th to 20th century AD). There has been an overall migration of the main channel from east to west across the study area over time. The location of avulsion nodes changed along the length of the river, mainly downstream over time, but with a cluster of avulsion events near Babylon and a notable man‐made interference in the 20th century at the Hindiya Barrage. 相似文献
164.
Monetary valuation of ecosystem services enables more accurate accounting of the environmental costs and benefits of policies, but this has rarely been applied in developing countries. In such contexts, there are particular methodological and epistemological challenges that require novel valuation methodologies. This paper introduces a new participatory, deliberative choice experiment approach conducted in the Solomon Islands. The research aimed to determine the value people placed on ecosystem services and whether participatory interventions to elicit deeper held values influenced the preferences expressed. Results found that the initial willingness to pay for a number of tropical forest ecosystem services amounted to 30% of household income. Following deliberative intervention exercises, key ecosystem services effectively became priceless as participants were unwilling to trade them off in the choice experiment scenarios, regardless of financial cost. The group based deliberative approach, combined with participatory interventions, also resulted in significant learning for participants. This included a more sophisticated view of ecological-cultural linkages, greater recognition of deeper held values, and greater awareness of the consequences of human actions for the environment. The use of a group-based participatory approach instead of a conventional individual survey helped to overcome many of the practical difficulties associated with valuation in developing countries. Given the impact of learning on valuation outcomes, participation and deliberation should be integrated into valuation of any complex good, both in developing and developed economies. However, such a methodology raises questions about how valuation can deal with unwillingness to trade-off key ecosystem services, which results in the breakdown of monetary valuation methods. Evaluation of the appropriateness of valuation processes and methodologies for assessing deeper held values and use of mixed-method approaches will be essential to ensure policies take into account the extent to which human life is dependent on ecosystem services. 相似文献
165.
Claus Rinner Byron Moldofsky Michael D. Cusimano Sean Marshall Tony Hernandez 《Transactions in GIS》2011,15(2):129-145
Injury from causes such as falls, traffic accidents, or violence is a major public health issue globally. Injury prevention research aims to identify vulnerable populations and places by analyzing the spatial patterns of demographic and socio‐economic risk factors associated with elevated injury rates. The stakeholders in injury prevention and control are often distributed across government and public health institutions, non‐profits, and even the private sector (e.g. insurance firms). While this situation calls for distributed, online research tools, their implementation may conflict with health data confidentiality and license limitations for socio‐economic data. In this article, we present the Online Injury Atlas for Ontario, which was designed with the explicit goal of making use of, and contributing to, the Canadian Geospatial Data Infrastructure. We propose a service‐based architecture that integrates publicly accessible map services with protected data layers. Thereby, we demonstrate the benefits of using spatial data infrastructures alongside private data at different levels of protection. In addition, we discuss the extensive data processing needs and specific cartographic design requirements of a Web atlas in the health and social sciences domain. 相似文献
166.
Structural features and metallogenesis of the Carlin-type Jinfeng (Lannigou) gold deposit, Guizhou Province, China 总被引:5,自引:0,他引:5
Chen Maohong Mao Jingwen Frank P. Bierlein Tony Norman Phillip J. Uttley 《Ore Geology Reviews》2011,43(1):217-234
Jinfeng, previously known as Lannigou, is the largest Carlin-type gold deposit in the Yunnan–Guizhou–Guangxi region in southwestern China. Gold mineralization in the Jinfeng deposit is almost entirely fault-hosted and structurally controlled, with very little disseminated ore occurring in the adjacent host rocks. The structural elements in the Jinfeng deposit can be subdivided into 3 groups comprising NS-, NW-, and NE-striking faults and folds, with NW-striking structures controlling the overall framework of the deposit. Four tectonic stages have been recorded in the Jinfeng area, i.e., rifting, orogenic compression, lateral transpression, and lithospheric extension. A series of contemporaneous normal faults, such as the N-striking and east-dipping F1 and F7 faults developed along the edges of a carbonate platform during basin rifting (D2–T2). These structures provided an initial framework for subsequent basin evolution, and also represent the principal hydrothermal conduits. A gradual change of the compression direction during the orogenic stage (T3) from E→W to NE→SW, gave rise to the NW-striking structures, including large, tight to overturned folds such as the Huangchanggou synclinorium and associated thrusts such as the F3 fault. The development of these orogenic, predominantly NE-dipping structures, as well as accompanying NE-striking dextral shear and transform faults (such as the F2 fault) along the margin of the Laizishan Dome established the structural pattern of the deposit area. The NW-striking folds were refolded by NE-striking superimposed folds during post-collisional lateral transpression (J1) and NW–SE directed compression. Oblique stress distribution gave rise to NS-trending compression and EW-trending extension, with dilational zones developing at the intersection of the F2 and the F3 faults east of the Laizishan dome. It is these dextral- and sinistral-normal dilational zones in which gold was precipitated during the main ore-forming event at Jinfeng. Following the main ore stage lithospheric extension occurred during the Yanshan stage (J2–K) resulting in minor reverse faults that in places cut pre-existing structures. The above four main structural deformation stages mirror the evolution of the Youjiang Basin from inception to basin inversion and post-orogenic collapse and renewed extension. Significant gold metallogenesis at Jinfeng occurred during the transition from collisional compression to extensional tectonics in the early Jurassic, and is focussed into intersections of F2 and F3 and fault splays adjacent to F3. This structurally controlled gold metallogenic model is likely to be applicable to analogous settings elsewhere in the Yunnan–Guizhou–Guangxi triangle area, and has implications for the targeting of Carlin-type gold mineralization in this region. 相似文献
167.
This paper discusses a secondary school education initiative focussing on environment and sustainability centred on a small urban stream. This initiative has passed through an engagement stage, involving the community and other schools, and is now being embedded in curriculum learning. A cross‐curricular learning programme has been trialled and points the way toward new types of educational models within secondary schools in accord with opportunities offered by the new school curriculum. Moreover, these opportunities have wider benefits across the primary, secondary and tertiary sectors as well as within the community. These benefits include vertically structured place‐based education, win‐win partnerships, rationalising of local resources and leadership and networking. Further developments within the context of integrated catchment management are ongoing. 相似文献
168.
Anton Kearsley Giles Graham Tony McDonnell Phil Bland Rob Hough Paul Helps 《Meteoritics & planetary science》2004,39(2):247-265
Abstract— Understanding the nature and composition of larger extraterrestrial bodies that may collide with the Earth is important. One source of information lies in the record of ancient impact craters, some of which have yielded chemical information as to the impacting body. Many deeply eroded craters have no remaining melt sheet or ejecta yet may contain impactor residue within basement fractures. The emplacement mechanism for fractionated siderophile residues is likely to be gaseous, although, melt droplets and some solid materials may survive. For breccia‐ and melt‐filled fractures to contain extraterrestrial material, they must form very early in the impact process. Most current numerical models do not dwell on the formation and location of early major fractures, although, fractures in and around small craters on brittle glass exposed to hypervelocity impact in low Earth orbit have been successfully simulated. Modelling of fracture development associated with larger craters may help locate impact residues and test the models themselves. 相似文献
169.
Tony Waltham 《Geology Today》2005,21(5):187-190
Silver mining in Bolivia exploited the richest hill on Earth to finance the imperial Spanish in the 16th century. The mines still operate at Potosi today, with primitive conditions underground, but silver production may be boosted by new geological understanding. 相似文献
170.
Anja Strφmme 《极地研究(英文版)》2002,13(1)
1 TheincoherentscattertechniqueTheuseofincoherentscatterradarsasapowerfulground baseddiagnostictoolforstudyingthenear EarthspaceenvironmentbeganwiththefirsttheoreticalpredictionsbyGordon( 1 958) ,andthefirstobservationsbyBowles( 1 958)afewmonthslater .Thereares… 相似文献