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201.
Samples of surface water, soil, sediment and plants from the Xunyang Hg mining area in Shaanxi Province, China, were analyzed to assess the effects of the Hg mining activities on the environment. The results show that: (1) the mining activities are sources of Hg to the environment surrounding the mine; (2) the environment, especially riverbeds in the Xunyang area, is contaminated with Hg and (3) Hg accumulation in cabbage leaves, the main vegetable for the local residents, is high, reaching concentrations that are 6–540 times higher than the maximum Hg concentration recommended for edible plants in China. Action should be taken to remediate contaminated sites, manage waste discharges and reduce the exposure of Hg to local residents by issuing advisories against consuming agricultural products grown in the area, which are contaminated with Hg. 相似文献
202.
While extensively occurring natural resources play a fundamental role in the survival and recovery of postwar populations,
their management is not presently part of the operational priorities in a peace process. Dependence on naturally occurring
food, fuel, water, secure locations, and products that can be obtained and sold quickly for dislocated, war-weary populations
is a primary approach to postwar livelihoods. The peace process, however, focuses on the logistical and institutional aspects
of security, demobilization, reintegration and humanitarian efforts. The result is profound degradation of the spatially extensive
resources necessary for longer-term recovery. The primary reason for the inattention to resource degradation in a peace process
is that conventional conservation approaches do not fit with the priorities of a peace process or attend to the immediate
needs of a postwar population; designed as they are for stable, peaceful settings. This article focuses on the need to derive
postwar natural resource management approaches which can work with the in-place priorities of a peace process. Four such approaches
are suggested, with successful examples from specific countries.
相似文献
Jon UnruhEmail: |
203.
Julia Olson 《Geoforum》2010,41(2):293-303
The oceans are not only being transformed through privatization as management moves towards market mechanisms, the oceans are also being “zoned”, with zoning increasingly proposed as the ideal conduit for weighting different uses of the ocean. This is concomitant with a move towards ecosystem-based management that also partakes in a policy environment imbued with the commodification of nature, in which environmental services are ranked and valued according to neoliberal percepts. Crucial to these projects are the utilization of GIS technologies. This paper considers these zones of preservation and sites of conflict through an ethnographic case study of the scallop fisheries of New England, examining conflicts between harvesters, different projects to map the fishery, and ongoing efforts to reseed scallop beds. The paper explores how participants themselves articulate the changing practices of fishing and farming, redefining boundaries of nature and culture. While reseeding projects, for example, arguably participate in the market logic of neoliberalism, at the same time they may resist and redefine the terms, as communities see themselves sowing the seeds of their own sustainability and changing the terms of what counts, literally, as nature. 相似文献
204.
John Menzies Jaap J.M. van der Meer Julia S. Wellner 《Proceedings of the Geologists' Association. Geologists' Association》2010,121(3):281-292
Micromorphology can be used in studying a wide range of earth materials. Within the last decades, the technique has been applied across an ever-widening range of sediments and materials. Micromorphology provides insight into sediments from various geological environments. Microstructures and the relationship of matrix (plasma) to skeleton grains offer an understanding of deposition, deformation, and postdepositional diagenesis. Examples from Germany and Antarctica illustrate the value of micromorphology providing a robust method for microstratigraphic interpretation. Micromorphology has proved invaluable in detecting toxic substances with sediments. Likewise, micromorphological examination of concrete has revealed new clues to processes of concrete ‘setting’ and diagenesis. 相似文献
205.
206.
Stacy Supak Huan Luo Laura Tateosian Kunsheng Fang Julia Harrell Cris Harrelson Andrew D. Bailey Hugh Devine 《Transactions in GIS》2012,16(2):89-104
By responding to potentially life‐threatening emergencies such as foodborne illnesses and water contamination, U.S. public health agencies play a vital role in promoting human health and protecting the environment. Local, state, and federal partners must collaborate to strategically plan initiatives, allocate resources, and evaluate emergency response activities. These collaborative decision‐making processes can be improved by using web‐based mapping applications for visualization and analysis. We developed a web‐based GIS framework which is applied to public health data for North Carolina's (NC) Department of Health and Human Services. The application visualizes all state‐regulated food service facilities and supports query and analysis tools crucial for food recalls or radiation contamination tracking. Built with PostgreSQL/PostGIS, GeoServer, and a customized GeoExplorer map viewer, the framework delivers a web‐based mapping tool that is flexible and Open Source. The flexibility of the framework is an important dimension of its scalability, allowing it to be customizable, modular, and portable so that it is easily configurable to support additional research and education initiatives. This approach reverses a trend toward application‐specific web mapping development in Open Source GIS. To demonstrate flexibility, we configured an additional website for forest landowner management to be used by another state agency, the NC Forest Service. 相似文献
207.
Julia Koschinsky Nancy Lozano-Gracia Gianfranco Piras 《Journal of Geographical Systems》2012,14(3):319-356
This article compares results from non-spatial and new spatial methods to examine the reliability of welfare estimates (direct and multiplier effects) for locational housing attributes in Seattle, WA. In particular, we assess if OLS with spatial fixed effects is able to account for the spatial structure in a way that represents a viable alternative to spatial econometric methods. We find that while OLS with spatial fixed effects accounts for more of the spatial structure than simple OLS, it does not account for all of the spatial structure. It thus does not present a viable alternative to the spatial methods. Similar to existing comparisons between results from non-spatial and established spatial methods, we also find that OLS generates higher coefficient and direct effect estimates for both structural and locational housing characteristics than spatial methods do. OLS with spatial fixed effects is closer to the spatial estimates than OLS without fixed effects but remains higher. Finally, a comparison of the direct effects with locally weighted regression results highlights spatial threshold effects that are missed in the global models. Differences between spatial estimators are almost negligible in this study. 相似文献
208.
Timothy Garn David A. Green Julia M. Riley Paul Alexander 《Monthly notices of the Royal Astronomical Society》2008,387(3):1037-1044
We present observations of the Lockman Hole taken at 610 MHz with the Giant Metrewave Radio Telescope (GMRT). Twelve pointings were observed, covering a total area of ∼5 deg2 with a resolution of 6 × 5 arcsec2 , position angle +45° . The majority of the pointings have a rms noise of ∼60 μJy beam−1 before correction for the attenuation of the GMRT primary beam. Techniques used for data reduction and production of a mosaicked image of the region are described, and the final mosaic is presented along with a catalogue of 2845 sources detected above 6σ. Radio source counts are calculated at 610 MHz and combined with existing 1.4-GHz source counts, in order to show that pure luminosity evolution of the local radio luminosity functions for active galactic nuclei and starburst galaxies is sufficient to account for the two source counts simultaneously. 相似文献
209.
Amber Wutich Melissa Beresford Julia C. Bausch Weston Eaton Kathryn J. Brasier Clinton F. Williams 《社会与自然资源》2020,33(7):941-948
AbstractThis study compares the efficiency of two analytic approaches—qualitative and quantitative—to social network analysis for identifying stakeholder groups. Social network data were collected from 23 water and agriculture stakeholders in Arizona, USA, and analyzed quantitatively and qualitatively. Analysis of the sample in the original order of data collection found qualitative analysis was more efficient, in that it yielded a stable result—the identification of four stakeholder groups—within 16 interviews. In contrast, the quantitative analysis did not produce a stable result after 23 interviews. Repeated analyses with randomized order and reverse order samples found qualitative approaches yielded more stable results, took about the same number of interviews to yield results, and produced slightly fewer stakeholder groups compared to quantitative approaches. Our findings suggest that, in resource-constrained projects, qualitative social network analysis for identifying stakeholder groups can provide an efficient alternative to conventional quantitative social network analysis. 相似文献
210.
Jasper A. Slingsby Abri de Buys Adrian D. A. Simmers Eric Prinsloo Greg G. Forsyth Julia Glenday Nicky Allsopp 《水文研究》2021,35(4):e14101
The Jonkershoek Forestry Research Station was established in the Mediterranean climate region of South Africa in 1935 to implement a multiple catchment experiment to determine the effects of afforestation on water yield. The experiment consists of six neighbouring catchments previously supporting indigenous fynbos shrublands, five of which were sequentially afforested with Pinus radiata plantations every 8 years from 1940 to 1980 and one kept as the control. They conclusively demonstrated a significant impact of afforestation on streamflow. The treatment catchments have seen subsequent plantation rotations since 1980 and rainfall and streamflow observations have been continued to date. Here we describe the site, experimental design, rainfall and streamflow records, instrumentation, and how to access the data. We also provide details of recently installed instrumentation, including full weather stations, fog gauges, and an eddy covariance flux tower. The Jonkershoek catchment experiment was the core of a globally significant interdisciplinary research programme (1935–1992) that shaped most environmental policies and practices relating to biodiversity, forestry, fire and water in South Africa and beyond. The South African Environmental Observation Network (SAEON) inherited the experiment in 2010 and is maintaining it as a long-term eco-hydrological research platform and global change observatory. 相似文献