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排序方式: 共有233条查询结果,搜索用时 31 毫秒
21.
ABSTRACTThe Australian government’s proposal to expand the Snowy Hydro Scheme to include a second pumped hydro energy storage (PHES) system, and support for feasibility studies for PHES in Tasmania, offer an opportunity to incorporate more intermittent renewable energy generation into the National Energy Market. However, the infrastructure construction required for PHES expansion may have negative effects for biodiversity in subalpine and alpine areas. To identify the potential effects of PHES on biodiversity in Kosciuszko National Park (KNP), this systematic literature review assesses: (i) the key environmental disturbances likely to arise from PHES construction; and (ii) the specific impacts of these construction processes on biodiversity in subalpine and alpine environments. We find that the effects of PHES construction-related disturbances are likely to be negative for subalpine and alpine biodiversity, with impacts including the proliferation of exotic flora, habitat loss resulting from vegetation clearing, altered landscape hydrology and reduced water quality. Management recommendations to limit these impacts are provided and further research is recommended to assess: (i) the effects of PHES on fish populations in alpine reservoirs; (ii) the utility of spoil as artificial habitat for endemic fauna; and (iii) the chemical and physical impacts of spoil dumping in alpine reservoirs. 相似文献
22.
Russell C. Hedberg II Arielle Hesse Doug Baldwin Jase Bernhardt David Pahl Retchless Jamie E. Shinn 《The Professional geographer》2017,69(1):107-116
Recent debates about the state of geography raise valuable questions about how the discipline can and should change in response to shifting institutional realities. Focusing on the breadth and interdisciplinarity of geography, these discussions often overlook the role of pedagogy—particularly graduate training—in adapting the discipline to new institutional landscapes. Drawing on experiences as current and recent geography doctoral students, we identify institutional seedlings of opportunity that can be cultivated toward a spectrum of alternative doctoral training models. These alternatives offer significant opportunities to better prepare early-career geographers for success and to solidify geography's position as a leader in interdisciplinary research. 相似文献
23.
There is growing recognition of the importance of ecosystem-based approaches for adaptation to climate change—it is a cost-effective measure that has multiple benefits and can overcome many of the drawbacks of more common engineering adaptation options. Viet Nam has a rich biodiversity and is also one of the most vulnerable countries impacted by climate change. Climate change policies have been adopted at national and local levels as well as by sector, making Viet Nam one of the nations to most systematically fulfill their obligation under the United Nations Framework Convention on Climate Change. Consequently, we have used Viet Nam as a case study, to assess the integration of ecosystem-based approach to adaptation to climate change. We found that ecosystem-based adaptation is being implemented in some projects but, overall, is inadequately considered by Viet Nam’s climate change policies. Instead, policies predominantly rename infrastructure projects as climate change adaptation and focus on hard solutions for disaster reduction, rather than responding to long-term climate change through ecosystem-based adaptation. Moreover, ecosystem-based adaptation projects have focused on only a few relevant types of ecosystems. Viet Nam should revise its existing climate change policies and sectoral strategies to integrate ecosystem-based adaptation across different scales of governance. As other nations develop adaptation policies at different scales, the lesson from Viet Nam is that engineering measures need to be balanced with ecosystem-based adaptation for more affordable and effective responses to climate change. 相似文献
24.
Current observations taken at depths between 630 and 830 m from the west coast South Island continental slope exhibit one‐ to four‐weekly periodicities superimposed on the semi‐diurnal tide. These variable flows at 630 m and otter large, longer‐timescale events have a significart onshore/offshore component of flow which leads to a similar transport of alongshore momentum and heat. 相似文献
25.
Ballast water exchange processes facilitate the dispersal and unnatural geographic expansion of phytoplankton, including harmful algal bloom species. From 2005 to 2010, over 45,000 vessels (≈ 8000 annually) travelled across Galveston Bay (Texas, USA) to the deep-water ports of Houston (10th largest in the world), Texas City and Galveston. These vessels (primarily tankers and bulkers) discharged ≈ 1.2 × 10(8) metrictons of ballast water; equivalent to ≈ 3.4% of the total volume of the Bay. Over half of the ballast water discharged had a coastwise origin, 96% being from US waters. Galveston Bay has fewer non-indigenous species but receives a higher volume of ballast water discharge, relative to the highly invaded Chesapeake and San Francisco Bays. Given the magnitude of shipping traffic, the role of Galveston Bay, both as a recipient and donor region of non-indigenous phytoplankton species is discussed here in terms of the invasibility risk to this system by way of ballast water. 相似文献
26.
John D. Skalbeck Donald M. Reed Randall J. Hunt Jamie D. Lambert 《Hydrogeology Journal》2009,17(1):215-228
Historically, drier types of wetlands have been difficult to characterize and are not well researched. Nonetheless, they are considered to reflect the precipitation history with little, if any, regard for possible relation to groundwater. Two seasonal coastal wetland types (wet prairie, sedge meadow) were investigated during three growing seasons at three sites in the Lake Michigan Basin, Wisconsin, USA. The six seasonal wetlands were characterized using standard soil and vegetation techniques and groundwater measurements from the shallow and deep systems. They all met wetland hydrology criteria (e.g., water within 30 cm of land surface for 5% of the growing season) during the early portion of the growing season despite the lack of appreciable regional groundwater discharge into the wetland root zones. Although root-zone duration analyses did not fit a lognormal distribution previously noted in groundwater-dominated wetlands, they were able to discriminate between the plant communities and showed that wet prairie communities had shorter durations of continuous soil saturation than sedge meadow communities. These results demonstrate that the relative rates of groundwater outflows can be important for wetland hydrology and resulting wetland type. Thus, regional stresses to the shallow groundwater system such as pumping or low Great Lake levels can be expected to affect even drier wetland types. 相似文献
27.
Jamie Peck 《The Professional geographer》2013,65(4):580-582
While linguistic diversity is an integral component of cultural landscapes, the spatial depiction of languages fails to represent all community members. Language is difficult to map and established guidelines are lacking. The perception of power conveyed is arguably the most meaningful design issue in language mapping, as most language maps inaccurately show one language per place. This research examines the cartographic visualization of linguistic diversity, contributing to our understanding of the perception of power through cartographic decisions, with the application of a linguistic diversity index. The resulting maps serve as new figures for linguistic diversity lessons in educational contexts. 相似文献
28.
Jamie Gillen 《Geoforum》2012,43(6):1163-1170
This paper contributes to the existing literature on positionality, ethics, research design, and the politics of the field by sketching power relations between an American researcher and Vietnamese respondents in Vietnam. I illustrate how two types of investments, financial compensation and gift exchange, “live” in the field as arbitrators of power relations between researcher and respondent. Specifically, I argue that financial and symbolic investments are important yet neglected aspects of the fieldwork experience for both investigators and research subjects because they allow both parties to deploy and negotiate multiple positionalities in the field. In sum, the paper makes three points: it outlines the multiple positionalities at play as scholars plan and execute their research; it introduces the concept of investment to field methods, with a focus on financial compensation and gift giving; and it demonstrates investment’s role in the negotiation of power between researcher and respondent. 相似文献
29.
Nadia Senechal Stéphane Abadie Edith Gallagher Jamie MacMahan Gerd Masselink Hervé Michallet Ad Reniers Gerben Ruessink Paul Russell Damien Sous Ian Turner Fabrice Ardhuin Philippe Bonneton Stéphane Bujan Sylvain Capo Raphael Certain Rodrigo Pedreros Thierry Garlan 《Ocean Dynamics》2011,61(12):2073-2098
A large multi-institutional nearshore field experiment was conducted at Truc Vert, on the Atlantic coast of France in early 2008. Truc Vert’08 was designed to measure beach change on a long, sandy stretch of coast without engineering works with emphasis on large winter waves (offshore significant wave height up to 8 m), a three-dimensional morphology, and macro-tidal conditions. Nearshore wave transformation, circulation and bathymetric changes involve coupled processes at many spatial and temporal scales thus implying the need to improve our knowledge for the full spectrum of scales to achieve a comprehensive view of the natural system. This experiment is unique when compared with existing experiments because of the simultaneous investigation of processes at different scales, both spatially (from ripples to sand banks) and temporally (from single swash events to several spring-neap tidal cycles, including a major storm event). The purpose of this paper is to provide background information on the experiment by providing detailed presentation of the instrument layout and snapshots of preliminary results. 相似文献
30.
This paper is part of a larger community health study aimed at delineating the determinants of health in Sarnia. The paper
specifically investigates Sarnia residents’ daily lived experiences, perceptions of and responses to living within the St.
Clair River “Area of Concern” (AOC) as designated by the federal government based on the hypothesis that relatively high levels
of environmental pollution in the region are negatively influencing human health. Results from in-depth interviews (N = 27) show that residents of Sarnia are conflicted by the elevation of awareness about environmental health threats by being
labelled within an AOC. Residents use their emotional and sensual experiences to adopt appropriate coping strategies to live
within a contaminated community. In contextualizing their everyday lived realities, residents argued that living in an AOC
demands personal acceptance of the conditions in Sarnia and awareness of “bad air days” to cope with pollution exposure. Yet,
residents were not willing to abandon Sarnia because of their cultural, social, and economical attachments to the place they
call home. These findings suggest the need for local health policies that incorporate local concerns and perceptions of how
environmental pollution affects people’s experiences and well-being. There is a necessity to involve community members as
central participants in the process of policy making. 相似文献