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101.
Wildfires are widely reviewed as key inputs to Mediterranean ecosystems. However, research is often flawed by major biases. (1) The approach adopted by most planners focusing on forest fires dismisses the human dimension of fire as a component of agricultural production systems. (2) The Wildland–Urban Interface (WUI) concept postulates that cities and wildlands/wildfires are, and should remain, worlds apart, a statement whose truth is increasingly questioned by recent disastrous “urban wildfires”. (3) The Mediterranean Basin as a fire-prone area is all the more fantasized, as it is almost never studied as a whole.The present paper takes a critical view of city–wildland/wildfire interrelationships through a large-scale study of the Mediterranean Basin based on MODIS MCD12Q1 (Land Cover Type) and MCD45A1 (Burned Area Product) data collected between 2001 and 2013. The Mediterranean is an ideal place to investigate, as its human-dominated and urbanized landscapes are known to be extremely vulnerable to fire hazards. Data processing reveals that (wild)fires and cities maintain indissoluble ties, as if both elements could not be considered mutually exclusive on a geographical basis. Urban sprawl, reduced rural autonomies, changes in forest covers, old agricultural practices, and military conflicts provide the framework for an extended mitigation process challenging the WUI concept as a space divider.  相似文献   
102.
The right to food is increasingly evoked by a range of actors, but there is not sufficient critical analysis of distinct interpretations of what this right means in practice. Through examination of a mineral extraction project with agricultural implications, this article explores diverse human rights narratives and illuminates associated corporate efforts to minimize recognition of food as a fundamental right. A British mining company proposes the Phulbari open pit coal mine in an agriculturally important region of Bangladesh. Highly contested by affected populations, clashes in 2006 between the police and protestors turned deadly in the area. In February 2012, a group of UN Special Rapporteurs cautioned the Government of Bangladesh regarding human rights violations associated with the planned mine. They warned that the project would displace hundreds of thousands of people, while destroying fertile agricultural land. In contrast, an ongoing publicity campaign by the corporation attempts to promote their intervention as a positive step, fully compliant with international human rights and corporate social responsibility standards. Taking this case as an exemplar, the article illuminates the pursuit of mining profit and the distinct use of human rights narratives by corporations and UN Special Rapporteurs. These diverse actors represent the layering of voices weighing in on mineral extraction and associated right to food concerns. Collectively, these layered narratives represent a new terrain for the promotion and contestation of mining and highlight the need to scrutinize mining practices in light of social responsibility and human rights claims being voluntary and self-regulated.  相似文献   
103.
The paper assesses the role for innovation of one aspect which has been generally overlooked by evolutionary economic geography: context. It analyses how context shapes the impact of collaboration on firm-level innovation for 1604 firms located in the five largest city regions of Norway. Specifically, the analysis shows how the benefits to firms of collaborating within regional, national, and international innovation networks are affected by the knowledge endowments of the region within which the firm is located. Using a logit regression analysis, we find, first, that only national and international networking have a significant positive impact on the likelihood of innovation (the former only for process innovation), whereas the regional knowledge endowments have no direct effect. Second, regional cooperation is particularly effective in regions with high investments in R&D, whereas international cooperation is important in regions with an educated workforce – and regional and national collaboration may be ineffective in such cases. We conclude that, in the case of Norway, context is essential in determining the capacity of firms to set up networks and innovate. Regions with an educated workforce can use the resulting absorptive capacity to successfully assimilate knowledge being diffused through global pipelines from faraway places. However, this absorptive capacity is likely to be heavily filtered if regional firms mainly rely on internal connections within Norway.  相似文献   
104.
The management of the sea has increased exponentially in the last half-century, and different academic disciplines have been vital in shaping this management. Human geography, despite its explicit focus on the human–environment nexus, has so far had little impact on human relations with the sea. Based on empirical research conducted in England and Scotland, we argue that human geography is uniquely placed to offer effective solutions to marine resource management problems, and that geographers have the potential to offer key insights into how human populations can best interact with the living seas. Three of the most important current scholarly ‘imaginations’ of the sea, and the policies they inform (economics and market-based management, conservation biology and area based protection, and anthropology and community management), are outlined. A potential ‘geographical imagination’ of the sea, drawing on key themes in contemporary scholarship is then presented, and grounded in empirical research. It is argued that human–ocean relations should be a key feature of geographical research agendas.  相似文献   
105.
This paper presents novel visualization techniques to simplify representation of the fourth‐order material stiffness tensor as a set of three‐dimensional geometric objects. Stiffness visualization aids in understanding the complex stiffness characteristics of highly non‐linear constitutive models including modelled material anisotropy and loading path dependent stiffness variation. Stiffness visualization is relevant for understanding the relationship of material stiffness to global behaviour in the analysis of a boundary value problem. The spherical pulse stiffness visualization method, developed in the acoustics field, is extended to visualize stiffness of geomaterials using three three‐dimensional objects. This method is limited to relatively simple constitutive models with symmetric stiffness matrices insensitive to loading magnitude and direction. A strain dependent stiffness visualization method is developed that allows the examination of material stiffness for a range of loading directions and is suitable for highly non‐linear and path dependent material models. The proposed stiffness visualization can be represented as 3‐D, 2‐D and 1‐D objects. The visualization technique is used to represent material stiffness and its evolution during simulated soil laboratory tests and deep excavation construction. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
106.
本文对我国环境工程地质的发展简况、研究现状和末来所面临的问题等进行了回顾、概括和展望,指出我国环境工程地质问题日趋复杂。从防御和保护环境出发,我国未来的环境地质问题将以沿海地区、长江中下游沿江地带和内陆大中城市地区为重点。建立经济、社会和环境协调发展的环境工程地质的科学体系已成为当务之急。  相似文献   
107.
Concentrations of persistent organic pollutants including polychlorinated biphenyls (PCBs), organochlorine (OC) pesticides and dioxin-like compounds were measured in green-lipped mussels, Perna viridis, collected from seven mariculture zones in Hong Kong between September and October in 2002 in order to evaluate the status, spatial distribution and potential sources of pollution in these areas. Concentrations ranged from 300 to 4400 ng/g lipid weight for total OCs and 170–1000 ng/g lipid weight for total PCBs (based on 28 congeners). Relatively smaller DDT concentrations in mussels compared with previous studies suggest reduced discharges of DDTs from nearby regions into Hong Kong waters. Detection of a mixture of HCH isomers in the mussels indicated that Hong Kong waters were predominantly contaminated by technical HCHs rather than lindane. Mussel samples from all sampling locations elicited significant dioxin-like activity in the H4IIE-luc bioassay. The greatest magnitude of dioxin-like response (39 pg TEQ/g wet wt.) was detected in mussels from Ma Wan in the western waters of Hong Kong, which is strongly influenced by the Pearl River discharge. Human health risk assessment was undertaken to evaluate potential risks associated with the consumption of the green-lipped mussels. Risk quotient (RQ) for dioxin-like compounds was greater than unity suggesting that adverse health effects may be associated with high mussel consumption.  相似文献   
108.
《The Journal of geography》2012,111(4-5):226-232
Abstract

The geographic skills, as outlined in Geography for Life, provide an avenue for assessing students' work in geography. If used across the scope and sequence of the curriculum, a common scoring guide based on these skills offers opportunities for students to demonstrate their ability to use inquiry approaches to study geography and to improve those abilities over time and over different geographic questions. If used consistently, a geographic skills scoring guide can also help to communicate to a broader audience of parents, administration, and the public as to what the discipline of geography encompasses.  相似文献   
109.
文章结合北京市某基坑支护工程实际,介绍了一种新型的地面锚拉式土钉墙支护结构的加固机理、设计计算及应用情况等.工程实践表明该项支护技术比较适合于较厚杂填土地层的深基坑工程,其技术经济效果显著.  相似文献   
110.
全球变化的生态系统适应性   总被引:20,自引:0,他引:20  
全球变化的适应性研究已经成为全球变化研究的重点,亦是制定全球变化适应对策的关键。基于全球变化的定义,从生态系统对全球变化适应的4个方面:①对大气CO2浓度变化的适应性;②对气候变化的适应性;③对CO2浓度与气候变化协同作用的适应性;④对人为干扰的适应性,综述了当前的研究成果,进而提出了未来关于全球变化的生态系统适应性研究需要重视的方面,尤其是关于生态系统对全球变化响应的阈值研究应引起高度重视。  相似文献   
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