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61.
A methodological proposal for the assessment of impacts due to linear infrastructures such as motorways, railways, etc. is presented. The approach proposed includes a series of specific issues to be addressed for each geomorphological feature analysed—both ‘static’ and ‘dynamic’—as well as a series of steps to be followed in the process.Geomorphic characteristics potentially affected were initially identified on the basis of a conceptual activities/impacts model that helps to single out geomorphic impacts related to environmental concerns for the area. The following issues were addressed for each individual impact: nature of potential effects; indicators that can be used to measure impacts; criteria of ‘geomorphologic performance’; procedure for measurement/prediction of changes; translation of geomorphologic impacts into significant terms from the viewpoint of human concerns; possible mitigation and/or compensation measures.The procedure has been applied to a case study corresponding to a new motorway in the Basque Country, northern Spain. Geomorphological impacts considered in this analysis included: (1) consumable resources; (2) sites of geomorphological interest; (3) land units with high potential for use, high productivity or value for conservation; (4) visual landscape; (5) slope instability processes. The procedure has been designed for implementation in a Geographic Information System (GIS) environment. Details are given on the application of the method to each individual impact analysed and results are presented in both numerical and map form.Impacts assessed were initially expressed by means of heterogeneous magnitudes, depending on the geomorphological feature considered. Those geomorphological impacts were then translated into significant terms and homogeneous magnitudes. Integration was carried out on the basis of impact values thus obtained. Final integrated results were also expressed in numerical and map form.The method proposed enables comparison of alternatives as well as ‘prediction’ and assessment of impacts in terms directly related to geomorphic characteristics. It also facilitates the expression of those impacts in terms that allow integration with other types of environmental impacts.  相似文献   
62.
The current paper analyses various environmental parameters in relation to wheat yields in Bordenave, Province of Buenos Aires, Argentina. The variables used are: precipitation (ppt), maximum (Tx) and minimum temperature (Tmi) as well as those obtained by applying the Palmer model. Decadic and phenological scales are used for data corresponding to the period 1977–2000. The stepwise method is used to obtain a multi-variate equation to calculate yield taking into account environmental variables only. For a five variates model the coefficient of determination, R2 equals 95.79% and the standard error of estimation is 129.0 kg ha−1. In the sample yields, the incidence of total variability for thermal variables is 42.7% and for hydrological variables, 53%. The value and sign of the correlation coefficients were analysed throughout the cultivation cycle. The α coefficient is mainly responsible for yield variance during tillering and stem elongation. There is good correlation with the values of Palmer's Drought Severity Index (PDSI) for the flowering and grain filling stages.  相似文献   
63.
数字化形变台站日常下载、处理直至管理数据,都应用《数字化通讯控制软件》、《形变前兆台站(网)数据处理系统》及《形变前兆数据库服务软件(台站版)》等三个软件交互进行,在实际使用过程中会遇到一些棘手的问题。本文结合我台的观测工作的实践,总结经验,以供台站同行共享。  相似文献   
64.
Based on back scattered electron images and electron micro-probe analysis results, four alteration layers, including a transition layer, a reticulated ferric oxide layer, a nubby ferric oxide layer and a cellular ferric oxide layer, were identified in the naturally weathering products of pyrite. These layers represent a progressive alteration sequence of pyrite under weathering conditions. The cellular ferric oxide layer correlates with the strongest weathering phase and results from the dissolution of nubby ferric oxide by acidic porewater. Leaching coefficient was introduced to better express the response of element mobility to the degree of pyrite weathering. Its variation shows that the mobility of S, Co and Bi is stronger than As, Cu and Zn. Sulfur in pyrite is oxidized to sulfuric acid and sulfate that are basically released into to porewater, and heavy metals Co and Bi are evidently released by acid dissolution. As, Cu and Zn are enriched in ferric oxide by adsorption and by co-precipitation, but they would re-release to the environment via desorption or dissolution when porewater pH becomes low enough. Consequently, Co, Bi, As, Cu and Zn may pose a substantial impact on water quality. Considering that metal mobility and its concentration in mine waste are two important factors influencing heavy metal pollution at mining-impacted sites, Bi and Co are more important pollutants in this case.  相似文献   
65.
In this study, the impact of geothermal water on ground and surface waters has been investigated in Akarcay Basin, Turkey. The release of thermal return water from district heating in the city of Afyon and from thermal baths has a considerable environmental impact on the main stream. Historical analyses of stream water quality data show that the present pollution is associated primarily with thermal return water of district heating system. Currently, about 6% of stream water comprises of thermal water. The pollution seems to degrade the water quality in Lake Eber. Streambed sediments were found to be in equilibrium with polluted water and may lead to additional pollution in lake water. Thermal groundwater intrusion to fresh water production wells was detected mainly at sites close to geothermal fields. Solutions to remove thermal water from surface environment are suggested.  相似文献   
66.
As an approach to development, many see capitalism as reaching across an enormous range of scholarly domains and political interests. For some time geographers and others have begun to conceptualize capitalism as less of a system of intrinsic economic logic and more a collection of social and discursive relationships. By bringing capitalism into the “discursive world” these commentators and others have provided the theoretical ground for an exploration of alternative economic forms, especially those that are more socially and ecologically just. This paper makes an argument for putting sustainable development through the same theoretical scrutiny. Drawing on examples from the US we recruit the concept of “actually existing sustainabilities” from Altvater’s concept “actually existing socialisms” as an entry point to this conversation. Our purpose is to show that the potential for sustainability in the US exists in current local policies and practices if we rethink how we frame it.  相似文献   
67.
Tim Forsyth 《Geoforum》2005,36(4):429-439
Public-private partnerships in environmental policy should not simply be viewed in instrumental terms as means of providing environmental infrastructure and services, but also as sites where norms of environmental concern and political accountability are formulated and replicated. Deliberative public-private partnerships--or partnerships that allow greater public participation in the formulation of these norms--may therefore become an important new form of local environmental governance and help make partnerships more relevant to local environmental needs. This paper examines case studies of public-private partnerships in waste-to-energy projects in the Philippines and India to identify how principles of institutional design may enhance the deliberative nature of public-private partnerships in environmental policy. The paper argues that current approaches to deliberative, or cooperative environmental governance concerning public-private partnerships need to acknowledge insights from network theory concerning the communication of environmental and political norms before they can be successfully transferred to developing countries.  相似文献   
68.
Quantifying the proportion of the river hydrograph derived from the different hydrological pathways is essential for understanding the behaviour of a catchment. This paper describes a new approach using the output from master recession curve analysis to inform a new algorithm based on the Lyne and Hollick ‘one‐parameter’ signal analysis filtering algorithm. This approach was applied to six catchments (including two subcatchments of these) in Ireland. The conceptual model for each catchment consists of four main flow pathways: overland flow, interflow, shallow groundwater and deep groundwater. The results were compared with those of the master recession curve analysis, a recharge coefficient approach developed in Ireland and the semi‐distributed, lumped and deterministic hydrological model Nedbør‐Afstrømings‐Model. The new algorithm removes the ‘free variable’ aspect that is typically associated with filtering algorithms and provides a means of estimating the contribution of each pathway that is consistent with the results of hydrograph separation in catchments that are dominated by quick response pathways. These types of catchments are underlain by poorly productive aquifers that are not capable of providing large baseflows in the river. Such aquifers underlie over 73% of Ireland, ensuring that this new algorithm is applicable in the majority of catchments in Ireland and potentially in those catchments internationally that are strongly influenced by the quick‐responding hydrological pathways. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
69.
In this intervention article I contribute to discussions of moral economy by arguing that scholars should reconsider the nature of value. Neoliberalism considers only exchange value. As a consequence neoliberal policies try to manage problems such as climate change with economic systems and instruments that are mis-calibrated to the material realities they are meant to represent. Value has spatial and temporal characteristics. Recognizing the spatial and temporal dynamics of value leads to new means of resource valuation, such as extending the time-frame of instruments and changing the nature of privatization. In conclusion, I argue for the need for new theories of use value.  相似文献   
70.
In this paper I argue that there has been a critical shift towards war by conservation in which conservation, security and counter insurgency (COIN) are becoming more closely integrated. In this new phase concerns about global security constitute important underlying drivers, while biodiversity conservation is of secondary importance. This is a significant break from earlier phases of fortress conservation and war for biodiversity. In order to develop a better understanding of these shifts, this paper analyzes the existing conceptual approaches, notably environmental security which seeks to understand how resources cause or shape conflict, and political ecology approaches that focus on the struggles over access to and control over resources. However, this paper indicates the limitations of these existing debates for understanding recent shifts, which require a fresh approach. I chart the rise of the narrative I call poachers-as-terrorists, which relies on the invocation of the idea that ivory is the white gold of Jihad, a phrase which is closely associated with an Elephant Action League (EAL) report in 2012 which claimed Al Shabaab used ivory to fund its operations. This narrative is being extended and deepened by a powerful alliance of states, conservation NGOs, Private Military Companies and international organizations, such that it is shaping policies, especially in areas of US geo-strategic interest in Sub-Saharan Africa. As a result conservation is becoming a core element of a global security project, with significant implications for conceptual debates and for conservation practice on the ground.  相似文献   
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