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31.
Siri Veland Richard Howitt Dale Dominey-Howes Frank Thomalla Donna Houston 《Global Environmental Change》2013,23(1):314-326
The challenge of reaching common understanding of the processes and significance of environmental change amounts to a procedural vulnerability in climate change research that hinders successfully translating knowledge into equitable and effective adaptation policy. This article presents findings from research with Indigenous participants in West Arnhem, Australia, and identifies a procedural vulnerability to climate change research, where perceptions of change and their meaning have their context in Dreaming that supersedes and parallels Western scientific discourses of hazard and risk, but that are marginalised in studies and policies on climate change. This paper argues that moves to adapt remote Indigenous Australian communities to climate change risk missing the mark if they (a) assume that a strong reliance on particular ecosystem configurations makes Indigenous cultures universally vulnerable to environmental change, (b) do not recognise cosmologically embedded risks that are determined by Indigenous capacity to take care of country, and (c) do not recognise colonisation as an ongoing disaster in Indigenous Nations, and therefore treat secondary disasters such as poverty, ill health and welfare dependence as primary contributors to high climate change vulnerability. Procedural vulnerabilities contribute to policy failure, and in Australian contexts pose a risk of conceiving solutions to climate change vulnerability that involve moving people out of the way of environmental risks as they are conceived within colonial traditions, while moving them into the way of risks as conceived through the eyes of remote Indigenous communities. This research joins recent publications that encourage researchers and policy-makers to epistemologically ground proof risk assessments and to listen and engage in conversations that create ways of ‘seeing with both eyes’, while not being blind to the hazards of colonisation. 相似文献
32.
Geotechnical engineering practice for collapsible soils 总被引:3,自引:0,他引:3
Sandra L. Houston William N. Houston Claudia E. Zapata Chris Lawrence 《Geotechnical and Geological Engineering》2001,19(3-4):333-355
Conditions in arid and semi-arid climates favor the formation of the most problematic collapsible soils. The mechanisms that account for almost all naturally occurring collapsible soil deposits are debris flows, rapid alluvial depositions, and wind-blown deposits (loess). Collapsible soils are moisture sensitive in that increase in moisture content is the primary triggering mechanism for the volume reduction of these soils. One result of urbanization in arid regions is an increase in soil moisture content. Therefore, the impact of development-induced changes in surface and groundwater regimes on the engineering performance of moisture sensitive arid soils, including collapsible soils, becomes a critical issue for continued sustainable population expansion into arid regions.In practicing collapsible soils engineering, geotechnical engineers are faced with (1) identification and characterization of collapsible soil sites, (2) estimation of the extent and degree of wetting, (3) estimation of collapse strains and collapse settlements, and (4) selection of design/mitigation alternatives. Estimation of the extent and degree of wetting is the most difficult of these tasks, followed by selection of the best mitigation alternative. 相似文献
33.
AK Jain RS Hooda J Nath ML Manchanda 《Journal of the Indian Society of Remote Sensing》1991,19(2):125-134
Aerial photographs for the year 1965 and 1975 and Landsat TM (FCC) 1986 data on 1:50,000 scale were used to map and monitor the pattern of growth and development of Hisar Town during the last 20 years. The different landuse categories identified are residential, commercial, industrial, recreational, vacant lands etc. The original shape of the town was nucleated one, but presently it is star-shaped, which is due to extension of the urban centre along the radiating roads. It has mainly elongated itself along the Delhi and Rajgarh roads. The presence of Government Livestock Farm (GLF), Equine Breeding Farm and HAU Farm towards North-west of the town has completely checked its growth on these sides. The total residential-cum-commercial area has nearly doubled during 1965–1975 and trebled by 1986. The change in net area under different types of urban land-use categories, described above has also been calculated. Degraded scrub lands and sandy wasteland on the fringes of the town have been identified where further development can be planned to avoid encroachment on good agricultural lands. Recommendations have been given for future urban planning of the town. 相似文献
34.
Dr. Scott B. Smithson Philip R. Fikkan Robert S. Houston 《Contributions to Mineralogy and Petrology》1971,31(3):228-237
Diopside granofels layers are associated with other metasedimentary rocks and gneisses near McMurdo Sound, Antarctica. Disrupted diopside granofels layers form tectonic inclusions which may have reaction rims of amphibolite. This amphibolite may either be a typical hornblende-plagioclase amphiholite or a hornblende-quartz amphibolite according to the initial composition of the diopside granofels. Chemical analyses of the reaction rims show that some of the amphibolites have major element compositions near tholeiitic basalt but that a sedimentary origin could be recognized for others that are high in silica. During amphibolitization, the diopside granofels loses Ca and gains Fe and Mg by mutual exchange of material with the surrounding rock over short distances. The metasomatic amphibolites fall on the igneous differentiation trend in a Niggli mg-c plot. At least small volumes of metasedimentary rock can attain the composition of basalt by amphibolitization in a metasomatic reaction rim. 相似文献
35.
The adoption of best management practices to reduce agricultural water contamination 总被引:2,自引:0,他引:2
Nonpoint source water pollution generated by agricultural production is considered a major environmental issue in the United States and Europe. One strategy in the United States has been to adopt various measures, called best management practices (BMPs), to reduce water pollution. Our research addresses legal institutions and the applied use of BMPs, and discusses compensatory payments to reduce nitrogen fertilization levels. Models employed in Georgia and Baden-Wuerttemberg evaluate institutional constraints of payments to reduce nitrogen usage, penalties for excessive leaching, and financial incentives for meeting minimum mineralized nitrogen levels. By modeling net returns, preferred economic strategies for producers are identified. Results show that while BMPs can reduce agricultural nonpoint contamination, pollution abatement may be costly to producers. Thus, reduced pollution probably will require some type of government intervention. 相似文献
36.
Steven Greco Stanley Ulanski Michael Garstang Samuel Houston 《Boundary-Layer Meteorology》1992,58(1-2):91-115
A low-level nocturnal wind maximum is shown to exist over extensive and nearly undisturbed rainforest near the central Amazon city of Manaus. Analysis of meteorological data collected during the 1985 and 1987 Amazon Boundary Layer Experiments (ABLE 2A and 2B) indicates the presence of this nocturnal wind maximum during both the wet and dry seasons of the Central Amazon Basin. Daytime wind speeds which are characteristically 3–7 m s-1 between 300 and 1000 m increase to 10–15m s-1 shortly after sunset. The wind speed maximum is reached in the early evening, with wind speeds remaining high until several hours after sunrise. The nocturnal wind maximum is closely linked to a strong low-level inversion formed by radiational cooling of the rainforest canopy. The night-time inversion extends up to 300 m with strong vertical shear of the horizontal wind below the inversion top and uniformly strong horizontal winds above the inversion top. Frictional decoupling of the air above the inversion from the rough forest below, however, is responsible for only part of the observed increase. Surface and low-level pressure gradients between the undisturbed forest and the large Amazon river system and the city of Manaus are shown to be responsible for much of the nocturnal wind increase. The pressure gradients are interpreted as a function of the thermal differences between undisturbed forest and the river/city. The importance of both the frictional decoupling and the horizontal pressure gradient suggest that the nocturnal wind maximum does not occur uniformly over all Amazonia. We suspect that stronger low-level winds are pervasive under clear skies and strong surface cooling and that, in many places (i.e., near rivers), local pressure gradients enhance the low-level nocturnal winds. 相似文献
37.
Freezing rain (FZRA) is well documented as a major weather hazard, producing damage to structures, the environment, and humans,
and delaying various operations such as transportation. Assessing the risk of freezing rain events requires information for
various areas of the nation about the frequency, duration, and intensity of these events along with the associated weather
conditions that affect the damage caused by freezing rain. This includes temperatures (dry and wet bulb), the amount of precipitation,
and winds during freezing rain. The purpose of this work was to develop a national and regional climatology of freezing rain
events in the US for the period of 1928–2001 to addresses these conditions. 相似文献
38.
Serin Houston 《Geographical review》2019,109(4):562-579
While contentious national debates persist about the promise or peril of so‐called “sanctuary cities,” this article draws on an archive of U.S. subfederal policies that focused on local responses to immigration and enforcement from 2001–2014 to argue that sanctuary constitutes a process rather than a binary state of being. Such a conceptualization underscores the broad spectrum of policy endeavors that comprise sanctuary and shifts the focus away from a reductionist question of whether or not a place is a sanctuary to inquiries into how sanctuary functions as a process in both policy creation and application. I focus on sanctuary as a process to demonstrate its socio‐spatial heterogeneity and to highlight how the assertion of local values within sanctuary policies advances internal bordering. Textually analyzing sanctuary policies in this way illustrates how the process of sanctuary can simultaneously resist the bordering efforts of federal immigration enforcement and reborder local practices to cultivate belonging for citizens and noncitizens alike. 相似文献
39.
应用人工爆破地震波层析成像方法勘探地下速度结构。在海域、山地多种地质条件下进行了地震波层析成像方法定量勘探研究。依勘探目标体而异,通过设计震源频率、震源和观测仪器布局,提高观测分辨率,实现定量高精度速度结构勘探研究。勘探最大深度可达Moho界面;山地最高分辨率可达3 m。结果显示了该方法在近海区域和山区不同地质条件的适用性及不同勘探深度与勘探精度的实用性。在日本九州近海地域勘测中,同时使用了反射与折射2种走时资料,可以同时改善水平及垂向的分辨率。成像图显示了地下结构详细特征,如任意斜向的凹凸形状,或高角度逆冲错断构造,分辨率达到10 m。同时显示出这些复杂几何体的埋藏深度。结果表明,诸如地下断层形状,资源矿藏储舱结构异常体的复杂几何形状,都可期望在层析成像技术的勘探分辨能力之内。它对于地下结构研究,矿产资源勘探,工程环境地质研究都有重要意义。结果也显示了成像方法的运算收敛速度和计算稳定性在结构勘探中是适用的。 相似文献
40.
The Institute of Australian Geographers Urban Study Group and Australian Geographer present the first essay in our Leading Insights/Thinking Space partnership. We discuss Dr Natalie Osborne's 2018 essay, flag Dr Marilu Melo's 2019 essay and talk about creating a thinking space for the rising stars of Australian urban geography. 相似文献