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101.
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Didams Gideon Firuza Begham Mustafa Idakwo Victor 《Singapore journal of tropical geography》2021,42(1):107-131
This study assessed gully erosion susceptibility in Southern Gombe State, Nigeria. The objectives of the study were to: (1) prepare gully inventory of Southern Gombe State, (2) apply the Analytical Hierarchy Process to assess the contribution of gully erosion predisposing factors, and (3) produce a gully erosion susceptibility map of Southern Gombe State. Based on geomorphological study involving interpretation of Google Earth images and field surveys, 127 gullies were identified and 13 gully erosion predisposing factors assumed to influence gully erosion susceptibility were selected. Identified gullies were randomly split into training (89 or 70 per cent) and validation (38 or 30 per cent) datasets. The contribution of each gully erosion predisposing factor was obtained using the Analytical Hierarchy Process. The results indicated that slope (0.130), stream density (0.121), and distance from stream (0.121) play crucial roles in gully erosion susceptibility. By overlaying the gully erosion susceptibility factor maps, a gully erosion susceptibility map was created. A natural break method was then used to classify gully erosion areas into relatively safe (6.04 km2), less susceptible (3332.46 km2), moderately susceptible (1811.49 km2), highly susceptible (1146.35 km2), and extremely susceptible (1726.77 km2) categories. Field verification confirmed that the map accurately classified 92.11 per cent of the validation datasets, signifying the Analytical Hierarchy Process as a reliable method for gully erosion susceptibility assessment. The created gully erosion susceptibility map can assist land planners to identify critical gully erosion areas where prevention and mitigation actions should be implemented. 相似文献
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This article analyzes a political process in the aftermath of a disaster and explains why and how it led to maladaptation. Grounding Gramsci’s theory of the State on a case of post-disaster response to a fatal mudslide in the city of Sarno in Italy, this research argues that, under certain conditions, civil society and the ruling classes may coalesce to produce policies that are maladaptive. We unpack the mechanisms through which consent was reproduced in Sarno, and show how the claims of civil society were articulated and fused with the hegemonic goals of capital circulation and economic growth, reaffirming a view of government as only a provider of safety. A Gramscian treatment of the State as a process, and not as a thing, highlights that the main barrier to adaptation is not the lack of techno-managerial solutions. It is the lack of political struggle around the social reconfiguration of the logic and functions of the State. 相似文献
105.
1970年以来中国大陆25次6.8级以上地震前态矢量异常特征研究 总被引:2,自引:0,他引:2
利用态矢量方法对中国大陆1970年以来25次6.8级以上地震进行了较为全面的分析研究, 结果表明, 19次地震前3年内态矢量出现明显异常, 其中10次地震发生前60天内态矢量有明显的变化, 只有6次地震前态矢量变化不明显。 由此认为态矢量方法对强震具有一定的中期和短临预测能力。 研究结果还表明, 相对于态矢量增量的模、 态矢量方向的改变等参量, 态矢量的模在震前的变化更为敏感, 此外, 对于相同震级的地震, 最佳扫描区域尺度大小不一, 并对这些现象进行了一定的解释。 相似文献
106.
This study suggested a numerical model using the Tabu search algorithm along with the Adjoint State method to identify the hydrogeological characteristics of an anisotropic groundwater aquifer. The Tabu search algorithm was applied to identify the anisotropic transmissivity components to avoid a local optimum. Then, the Adjoint State method was used to calculate the sensitivity of the parameters in order to increase the efficiency of the optimization. For an anisotropic and homogeneous aquifer, results showed that the optimal procedure presented combining the Tabu search algorithm and the Adjoint State method might successfully identify the values of the transmissivity components. If the duration of the pumping test was long enough (12‐h pumping test), the value of the transmissivity components could be optimized with type‐curve, straight‐line, and Tabu search methods, along with the Adjoint State methods. If the duration of the pumping test was short (0·5‐h pumping test), the Tabu search method, along with the Adjoint State method proposed herein, might successfully optimize the transmissivity components. For an anisotropic but heterogeneous aquifer, results showed that the suggested optimal procedure still successfully identified the values of the transmissivity components. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
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In 2007 the EU Commission published the so-called “Blue Book” aimed at developing an Integrated Maritime Policy for the Union. Even though Norway is not an EU member and is usually referred to as a small state, this article shows how the Norwegian government was able to exercise significant influence on EU maritime policy development, positioning itself as one of the key actors. Applying the negotiation theory and tracing the process as it unfolded, this analysis identifies causal relationships leading to increased influence for Norwegian actors—particularly in respect to how issues concerning the Arctic became an integrated part of the policy. The paper concludes that even though the Norwegian actors had a strategic point of departure, utilizing objective advantages to maximize their own utility, their influence may also have been due to competence and sharing of knowledge. The article relies on official documents, but is to a large extent also based on interviews with key EU Commission and Norwegian governmental representatives. On an elevated, substantive analytical level the article contributes to the “small state” research agenda and its interest in how small states in international relations might influence policy outcomes and thrive in the international community. 相似文献
109.
《Geoforum》2015
Analyses of sustainable design and commodity networks often make a priori assumptions about the capacity of markets to provide solutions to environmental problems; and have a tendency to celebrate local scales of action. This paper offers a contrasting account, in which the national state sought to carefully manage scarce natural resources and to ensure equitable consumption at a time of deep crisis. We utilise the historical example of the British wartime Utility furniture scheme in order to draw out three lessons for sustainable and equitable environmental practice. First, we argue that national states do not simply provide an institutional backdrop to sustainable production but rather can act as important organising agents. Second, the paper emphasises that sustainability is best achieved through interventions across a commodity network, beyond simply modifications to a single node such as design. Finally, we underscore the value of ‘pragmatic centralism’ in environmental decision-making, calling attention to the collaborative practices that underpinned the scheme. The example of Utility’s adaptive responses—borne out of crisis, scarcity and shortage during wartime—offers much that is of intrinsic interest to current concerns about resource consumption and the drivers of sustainability in commodity networks. 相似文献
110.
中国"数字国土"工程的方法论研究 总被引:7,自引:1,他引:7
“数字国土”是新世纪的一项宏伟工程,也是对“数字地球”和“数字中国”战略计划的响应,其核心问题是分布式点源空间数据库和属性数据库建设。分布式主题数据库建模,“多S”结合与集成,三级网络结构,信息标准化体系,海量数据入库,计算机辅助设计等关键技术的攻克,是实现区域地质调查了与矿产资源的信息化前提,而信息安全是“数字国土”的保障,作为合理而完善的解决方案,除了制定总体规划和系统结构外,还应当制定切实可行的对策和实施步骤,这需要借鉴国际上国土资源信息系统建设和地球信息科学方向发展和最新成果,并根据我国国土资源勘查与管理的特殊布局,通过周密的系统分析和系统设计来制定。 相似文献