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71.
Wells located in the Colombian Andean foreland often produce biodegraded hydrocarbons and relatively fresh water (total dissolved solids concentrations of 2000 mg l?1 dominate across most of the basin). The ratio of water to hydrocarbon in the produced fluids is high and has often been interpreted by explorationists and simulation engineers as being due to massive meteoric water invasion. To challenge this hypothesis, previously published and existing data are compiled here, along with 68 new water samples collected from both the surface (rivers) and subsurface (production wells), which are analyzed for major elements, salinity, and stable isotope compositions. The data indicate a mixed origin for the water, which involves formation water, meteoric water, and a third source that we interpret as being related to diagenetic processes (such as clay dehydration). Analyses of the variation of the parameters from north to south and west to east allow us to define the mixtures as coming from waters of different origins and make it possible to determine the relative contribution of each source.  相似文献   
72.
2009~2010年,南京博物院、镇江博物馆对镇江市区双井路遗址进行考古勘探、发掘,发现并揭示出宋代漕河、清代关河河道,元末明初拖板桥,清代京口驿,宋、元粮仓仓基,宋代官署建筑基址等遗迹、遗址,出土宋代带官、昌字的建筑砖瓦及唐至清代遗物,为研究我国大运河漕运、宋元仓储建筑、镇江地域文化等提供了重要资料。  相似文献   
73.
The Ecology of Games (EoG) theory couples institutional rational choice with social network theory, articulating how transaction costs, social capital, and collective action dilemmas shape networks and network outcomes in polycentric governance systems. EoG literature has often focused on social–relational ties across organizational boundaries. However, jurisdictional fragmentation and increased reliance on private contractors in local public service delivery foster another source of network connectivity—shared personnel who work for multiple service providers. Drawing upon novel data of organizational personnel from more than 500 special purpose entities responsible for delivering drinking water to local neighborhoods in the Houston metro area in the state of Texas (United States), we examine how managerial, technical, and financial service delivery personnel connect otherwise independent organizations. We find that districts regulated by a common groundwater management agency and districts which contract with one another are both more likely to share technical and managerial personnel. By studying special districts that have overlapping personnel, we broaden the scope of the EoG framework to include additional layers of governance network complexity. As individual bureaucrats and service professionals play a key role in information transfer and innovation diffusion across organizations, shared personnel networks merit consideration as a mechanism for coordination and collective problem solving in fragmented urban systems.  相似文献   
74.
Public policy generally emerges from interactions among actors embedded within complex governance systems, composed of multiple actors and forums (issue‐based arenas where stakeholders repeatedly interact to resolve collective action problems). Such systems allow actors multiple forums wherein they can influence policy decisions. But actors do not value the decisions made in each forum equally, and it remains unclear how actors allocate resources across forums. This article links actor strategy to their influence within the forums the actors identify as most important (their primary forum). There is theoretical ambiguity about how actors invest their limited resources across the forums that affect their interests to maximize primary forum influence. Do they concentrate all their effort within the primary forum or participate more broadly? To answer this question, we offer two competing theories. First, broad participation may allow actors to develop political capital necessary to influence other actors and thus influence primary forum policies. The second approach notes the opportunity costs of broad participation—actors have fewer resources to invest in their primary forum. An analysis of stakeholder participation in the Sacramento–San Joaquin River Delta and Tampa Bay Watershed governance systems demonstrates that broader participation is associated with greater primary forum influence.  相似文献   
75.
Where policy goals can be achieved through regulation of private firms, private provision of public services allows governments to separate public policies from their political costs by shifting those costs to the private sector. Over the past three decades, financial decoupling has emerged as a regulatory strategy for promoting conservation, especially in the energy sector. Decoupling refers to the separation of a firm’s revenues from the volume of its product consumed, which allows companies to pursue resource efficiency free from financial risk. Similarly, when private firms provide public services, they separate public policies from their political costs. This political decoupling allows governments to pursue controversial policies while avoiding their attendant political risks. Applied to environmental policy, this theory implies that potentially unpopular conservation policies are more likely to be adopted and succeed when implemented through private firms. As an initial test of the theory, we analyze California water utilities and their responses to that state’s drought from 2015–2017. Analysis shows that, compared with those served by local government utilities, private utilities adopted more aggressive conservation measures, were more likely to meet state conservation standards, and conserved more water.  相似文献   
76.
In this paper, we question an often-unchallenged assumption that we all talk about the same ‘thing’ when talking about water. Taking the Salween River in Myanmar as a case study, we draw on a growing body of hydrosocial literature to analyze the multiple ontologies of water. Conceptually, we take each ontology to be constituted of – and enacted within – a human-more-than-human assemblage, the spatiotemporal dimensions of which demarcate a ‘hydrosocial territory.’ We present three illustrations, namely: the role of the Union Government's National Water Resources Committee and how it manifests and is situated within an ontology of ‘modern Water’; a Karen indigenous initiative to establish a Salween Peace Park and an associated revealing of an ‘indigenous’ ontology; and plans for the construction of mainstream hydropower dams and electricity export to neighboring Thailand, where different water ontologies and their hydrosocial territories collide. We examine how multiple ontologies of water are contested through ‘ontological politics’, whereby human actors compete to further their own interests by naturalizing their ontology while marginalizing others. While not downplaying the role violent conflict plays, we argue that in the Salween basin ontological politics are an underappreciated terrain of contestation through which political authority and the power relations that underpin it are (re)produced, with implications for processes of state formation, territorialization and the ongoing peace negotiations.  相似文献   
77.
China's South–North Water Transfer Project (SNWTP) is a vast and still expanding network of infrastructure and institutions that moves water from the Yangtze River and its tributaries to cities in North China. This article aims to assess the SNWTP's impacts by beginning to answer seven questions about the project: How is the management of the SNWTP evolving? What are the problems to be resolved when managing SNWTP water within jurisdictions? What are the status and management of water quality in the SNWTP? What are the consequences of resettlements caused by the SNWTP? How is increased water supply affecting regional development? Is the SNWTP achieving its stated environmental goals? What are the sustainability credentials of the SNWTP? Drawing on primary and secondary data, the article demonstrates both that the opportunities and burdens characterising the project are highly uneven and that management systems are evolving rapidly in an attempt to enforce strict water quality targets. Furthermore, while the SNWTP may be helping to resolve groundwater overexploitation in Beijing, it is highly energy intensive, raising questions about its sustainability. Our analysis highlights the need to continue to interrogate the socio‐economic, environmental, and political implications of such schemes long after they are officially completed.  相似文献   
78.
明后期以降的史籍普遍认为南旺自元代起一直是会通河沿线的制高点“水脊”,元明会通河成败的关键就在于是否选择了南旺“水脊”作为分水口,这种观点不正确。南旺湖原本是梁山泊最后的余绪,地势低洼,明初宋礼引汶水到南旺济运后开始淤积,成化年间确定南旺分水核心地位后,挑出的泥沙堆积在运河和小汶河两岸形成土山地貌,构成明后期以降人们眼中的“水脊”意象。即南旺“水脊”形成于明代中叶,是汶水泥沙淤积和人工挑浚堆积的结果。据此,需重新审视元明会通河成败的原因,讨论明代中叶南旺“水脊”的形成对会通河水源从暴虐黄河水到安稳汶河水的转变的意义及其对明中叶以降治黄原则的深远影响。  相似文献   
79.
明清时期,福州西湖水环境总体趋劣。明代西湖水源较为充足,水质状况良好;万历以降,受民间占垦等社会因素影响,湖域面积缩减,水质日渐趋下;清代中后期,福州城内水道淤浅,江潮渐绝,西湖水源趋向单一。明清时期西湖水环境的变动,除了受区域气候干湿变化、山地森林水土保持以及湖泊含沙量的影响之外,还与人为的水地之争密切相关。由于人地关系紧张,加之水资源权属不清、新垦湖田税赋征收模糊等,获取湖利的必然性刺激了民间占湖为地的行为。地方官府也曾采取如修闸筑坝护堤、追返侵地还湖、清理粪秽淤泥等治理措施,并取得阶段性成效,但受区域人口、土地资源与生存环境等社会经济因素的影响,西湖历经多次治理仍积弊难除。  相似文献   
80.
Michael H. Finewood 《对极》2016,48(4):1000-1021
This paper explores Pittsburgh's water governance to consider the way divergent approaches to urban stormwater management reproduce existing urban metabolisms and belie more radical possibilities for the urban hydro‐social cycle. Federal action has forced municipalities in the Pittsburgh metropolitan region to make changes to its urban water systems and develop a plan to comply with water quality regulations. Within Pittsburgh's water governance debates, compliance centers on various sets of technological strategies for defining and solving purportedly wicked urban environmental problems. Urban political ecology, here, is used to deconstruct the tensions and convergences between these different stormwater governance strategies. I argue that green infrastructure approaches (whose intentions are to expand practice and participation) are framed by dominant grey epistemological approaches. In this view, alternative and creative forms of greening the city may not necessarily represent a more democratic process, but instead reproduce uneven urban landscapes under greener cover.  相似文献   
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