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971.
972.
Henrietta Nittby Bengt Widegren Morten Krogh Gustav Grafström Henrik Berlin Gustav Rehn Jacob L. Eberhardt Lars Malmgren Bertil R. R. Persson Leif G. Salford 《The Environmentalist》2008,28(4):458-465
We have earlier shown that radio frequency electromagnetic fields can cause significant leakage of albumin through the blood–brain
barrier of exposed rats as compared to non-exposed rats, and also significant neuronal damage in rat brains several weeks
after a 2 h exposure to a mobile phone, at 915 MHz with a global system for mobile communications (GSM) frequency modulation,
at whole-body specific absorption rate values (SAR) of 200, 20, 2, and 0.2 mW/kg. We have now studied whether 6 h of exposure
to the radiation from a GSM mobile test phone at 1,800 MHz (at a whole-body SAR-value of 13 mW/kg, corresponding to a brain
SAR-value of 30 mW/kg) has an effect upon the gene expression pattern in rat brain cortex and hippocampus—areas where we have
observed albumin leakage from capillaries into neurons and neuronal damage. Microarray analysis of 31,099 rat genes, including
splicing variants, was performed in cortex and hippocampus of 8 Fischer 344 rats, 4 animals exposed to global system for mobile
communications electromagnetic fields for 6 h in an anechoic chamber, one rat at a time, and 4 controls kept as long in the
same anechoic chamber without exposure, also in this case one rat at a time. Gene ontology analysis (using the gene ontology
categories biological processes, molecular functions, and cell components) of the differentially expressed genes of the exposed
animals versus the control group revealed the following highly significant altered gene categories in both cortex and hippocampus:
extracellular region, signal transducer activity, intrinsic to membrane, and integral to membrane. The fact that most of these
categories are connected with membrane functions may have a relation to our earlier observation of albumin transport through
brain capillaries. 相似文献
973.
Evolution of a Mediterranean Coastal Zone: Human Impacts on the Marine Environment of Cape Creus 总被引:1,自引:0,他引:1
This study presents an integrated analysis of the evolution of the marine environment and the human uses in Cape Creus, a
Mediterranean coastal area where intense commercial fisheries and recreational uses have coexisted over the last fifty years.
The investigation synthesizes the documented impacts of human activities on the marine environment of Cap de Creus and integrates
them with new data. In particular, the evolution of vulnerable, exploited species is used to evaluate the fishing impacts.
The effects of area protection through the establishment of a marine reserve in the late 1990s and the potential climate change
impacts are also considered. The evolution of the human uses is marked by the increasing socioeconomic importance of recreational
activities (which affect species and habitats) in detriment to artisanal and red coral fisheries (which principally affect
at a species level). Overall, populations of sedentary, vulnerable exploited species, hard sessile benthic invertebrates,
and ecologically fragile habitats, such as seagrass meadows, the coralligenous and infralittoral algal assemblages have been
the most negatively impacted by anthropogenic activities. Albeit human uses currently constitute the largest negative impact
on the marine environment of Cap de Creus, climate change is emerging as a key factor that could have considerable implications
for the marine environment and tourism activities. The establishment of the marine reserve appears to have had little socioeconomic
impact, but there is some evidence that it had some positive biological effects on sedentary, littoral fishes. Results demonstrate
that the declaration of a marine reserve alone does not guarantee the sustainability of marine resources and habitats but
should be accompanied with an integrated coastal management plan. 相似文献
974.
城市光污染侵害案件法律适用问题的探讨 总被引:1,自引:0,他引:1
在城市光污染侵害案件日益增多的同时,我国光污染侵害的法律救济手段和救济结果却不尽人意。虽然我国在宪法、环境保护法等法律、法规及民法中都有处理光污染侵害案件的法律依据,但由于缺少直接的规定,使环境保护法律体系存在太大的缺陷。因此,亟待制定有关的标准和修改相关的法律,从而更好地防治光污染,维护受害人的合法权益。 相似文献
975.
Resource managers require objective methodologies to optimize decisions related to forest road deactivation and other aspects of road management, especially in steep terrain, where road-related slope failures inflict extensive environmental damage. Decision analysis represents a systematic framework that clearly identifies real options and critical decision points. This framework links current decisions with expected future outcomes and provides advantages such as a common currency to systematically explore the liability consequences of limited budget expenditures to road deactivation and other road-related activities. Furthermore, the decision framework prevents the analysis from becoming hopelessly entangled by the vast number of possibilities generated by the alternative occurrences, magnitudes, and consequences of landslide/debris flow events and provides the information required for the first step of an adaptive management process. Here, a structured analysis of potential environmental risks for a road deactivation project in coastal British Columbia, Canada is presented. The application of decision analysis generates a ranking of the expected benefits of proposed deactivation activities on various road sections. The ranking distinguishes between road sections that offer high expected benefit from those that offer moderate to low expected benefit. Seventeen of 171, 100–m road segments accounted for 18% of the cumulative cost and 98% of the cumulative expected net benefits from road deactivation. Furthermore, the cost of deactivating a section of road is related to the expected benefit from such deactivation, thus providing the basis for more effective resource allocation and budgeting decisions. 相似文献
976.
Fluctuations of bird abundances in the Midwest region of the United States have been attributed to such factors as landscape change, habitat fragmentation, depredation, and supplemental feeding. However, no attempt has been made to estimate the collective role of landowner activities that may influence birds across a landscape. To investigate how landowners might influence birds when the majority (> 90%) of land is privately owned, we surveyed all 1694 private domestic landowners living on three breeding bird survey routes (120 km) that represent a continuum of rural-to-urban landscapes in Southeastern Michigan from October through December 2000. Our survey was designed to investigate (1) the proportion of landowners involved in bird feeding, providing bird houses, planting or maintaining vegetation for birds, gardening, landscaping, applying fertilizer, and applying pesticides or herbicides; (2) whether differences existed between urban, suburban, and rural landowner activities; and (3) whether landowners that carried out a given activity were sociodemographically different from those who did not. Of the 968 respondents (58.5% response rate), 912 (94%) carried out at least one of the activities on their land and the average landowner carried out 3.7 activities. A total of 65.6% fed birds, 45.7% provided bird houses, 54.6% planted or maintained vegetation for birds, 72.7% gardened, 72.3% landscaped, 49.3% applied fertilizer, and 25.2% applied pesticides or herbicides. Significant differences existed between the landscapes, with rural landowners having more bird houses and applying pesticides or herbicides in greater frequency. Similarly, urban landowners had a greater density of bird feeders and houses, but planted or maintained vegetation in the lowest frequency. Participation in activities varied by demographic factors, such as age, gender, and occupation. Scaling each activity to all landowners, including nonrespondents, across all landscapes indicates that between 14% and 82% of landowners may be engaged in a particular activity, with application of pesticides or herbicides having the least potential involvement (13.9%–55.4%) and gardening having the greatest potential involvement (40.1%–81.6%). Taken collectively, our results indicate that landowners are both intentionally and unintentionally engaged in a wide range of activities that are likely to influence bird populations. 相似文献
977.
978.
Bergquist DA 《Environmental management》2007,40(5):787-802
This article discusses environmental sustainability in aquaculture and its contribution to poverty alleviation, based on field
studies in Sri Lanka and the Philippines. The aquaculture practices studied are the monoculture of the black tiger prawn (Penneaus monodon) and milkfish (Chanos chanos) and the polyculture of the two species together with the mud crab (Scylla serrata). Factors affecting economic viability, social equity and environmental impacts in aquaculture are discussed and used to
illuminate local and regional differences between aquaculture in Sri Lanka and the Philippines. Findings indicate that the
most significant difference is the level of participation by local people (i.e., people originating ≤10 km away from the farm
location). In the Philippines, 84 % of the people involved in aquaculture are locals, whereas in Sri Lanka, 55% are outsiders.
Whether differences between the two areas can be explained by analyzing regional conditions, which might have resulted in
different aquaculture practices, is discussed. In Sri Lanka, semi-intensive shrimp monoculture is currently the most common
practice, whereas in the Philippines, extensive shrimp/fish polyculture is more common. Previous studies, as well as fieldwork,
indicate that extensive culture practices reduce environmental impacts and benefit local people more. Sustainability in aquaculture
is, however, also dependent on the extent of mangrove conversion into ponds. As such, extensive and locally owned farms do
not necessarily result in an all but sustainable situation. Keeping this in mind, it is discussed if extensive polyculture
practices might result in a more sustainable aquaculture, both environmentally and socioeconomically. 相似文献
979.
Analysis tools that combine large spatial and temporal scales are necessary for efficient management of wildlife species,
such as the burrowing owl (Athene cunicularia). We assessed the ability of Ripley’s K-function analysis integrated into a geographic information system (GIS) to determine changes in burrowing owl nest clustering
over two years at NASA Ames Research Center. Specifically, we used these tools to detect changes in spatial and temporal nest
clustering before, during, and after conducting management by mowing to maintain low vegetation height at nest burrows. We
found that the scale and timing of owl nest clustering matched the scale and timing of our conservation management actions
over a short time frame. While this study could not determine a causal link between mowing and nest clustering, we did find
that Ripley’s K and GIS were effective in detecting owl nest clustering and show promise for future conservation uses. 相似文献
980.
Faezeh Ghanati Parviz Abdolmaleki Majid Vaezzadeh Elham Rajabbeigi Mohammad Yazdani 《The Environmentalist》2007,27(4):429-434
In the present research, the effects of static magnetic field, with or without iron on the growth, the activity of certain
enzymes (like polyphenol oxidase and phenyle alanine ammonialyase), the content of phenolic compounds and the essential oil
composition of sweet basil (Ocimum basilicum) were studied. Treatment of plants with static magnetic field with or without iron led to decrease of the growth of plants
as well as decrease in the activity of phenyle alanine ammonialyase and of phenolic compounds content. In addition in those
plants exposed to magnetic field the amount of essential oils, notably of methyl chavicol, was increased. Exposure of plants
to the magnetic field decreased the activity of polyphenol oxidase, whereas treatment of plants with iron when exposed to
magnetic field increased polyphenol oxidase activity. In this group the content of essential oil was reduced. 相似文献