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561.
The repurposing of military lands is common in many parts of the world and presents a variety of conservation opportunities. This study examines land cover at Big Oaks National Wildlife Refuge, Indiana (U.S.A.) as it transitioned from military proving ground to wildlife refuge from 1985 to 2013. We use remote sensing, semi-structured interviews, and a review of planning and management documents to examine this transition. Limited change in land cover composition and distribution are detected, despite changes in use and management. This landscape similarity relates to similarities in land management practices, and the impact of landscape history on current management practices. The findings suggest that military use and conservation objectives at this site yield similar land covers and are not necessarily in contrast to each other. As military base closures continue, the potential to maintain and expand conservation opportunities on these lands will likely grow in importance. 相似文献
562.
563.
An Index to Measure Depreciation in Air Quality in Some Coal Mining Areas of Korba Industrial Belt of Chhattisgarh, India 总被引:1,自引:0,他引:1
Singh G 《Environmental monitoring and assessment》2006,122(1-3):309-317
The comparison with National Ambient Air Quality Standards does not always depict a true pic-ture of the Air Quality Status of a study area. As an alternative an index that measures depreciation in Air Quality on more realistic terms has been proposed and
applied to the ambient air monitoring data collected from some areas of Korba Coalfields in India. Results have been discussed in detail to illustrate the applica-tion of the proposed index and utility in bringing out more realistic air quality assessment. 相似文献
564.
Maramba NP Reyes JP Francisco-Rivera AT Panganiban LC Dioquino C Dando N Timbang R Akagi H Castillo MT Quitoriano C Afuang M Matsuyama A Eguchi T Fuchigami Y 《Journal of environmental management》2006,81(2):135-145
Abandoned mines are an important global concern and continue to pose real or potential threats to human safety and health including environmental damage/s. Very few countries had government mine regulation and reclamation policies until the latter part of the century where legal, financial and technical procedures were required for existing mining operations. Major reasons for mine closure may be mainly due to poor economies of the commodity making mining unprofitable, technical difficulties and national security. If the mine is abandoned, more often than not it is the government that shoulders the burden of clean-up, monitoring and remediation. The topic of abandoned mines is complex because of the associated financial and legal liability implications. Abandoned mercury mines have been identified as one of the major concerns because of their significant long-term environmental problems. Primary mercury production is still ongoing in Spain, Kyrgzystan, China, Algeria, Russia and Slovakia while world production declined substantially in the late 1980s. In the Philippines, the mercury mine located southeast of Manila was in operation from 1955 to 1976, before ceasing operation because of the decline in world market price for the commodity. During this time, annual production of mercury was estimated to be about 140,000 kg of mercury yearly. Approximately 2,000,000 t of mine-waste calcines (retorted ore) were produced during mining and roughly 1,000,000 t of these calcines were dumped into nearby Honda Bay to construct a jetty to facilitate mine operations where about 2000 people reside in the nearby three barangays. In October, 1994 the Department of Health received a request from the Provincial Health Office for technical assistance relative to the investigation of increasing complaints of unusual symptoms (e.g. miscarriages, tooth loss, muscle weakness, paralysis, anemia, tremors, etc.) among residents of three barangays. Initial health reports revealed significant elevation of blood mercury levels exceeding the then recommended exposure level of 20ppb in 12 out of the 43 (27.9%) residents examined. The majority of the volunteers were former mine workers. In this study the abnormal findings included gingivitis, mercury lines, gum bleeding and pterydium. The most common neurologic complaints were numbness, weakness, tremors and incoordination. Anemia and elevated liver function tests were also seen in a majority of those examined. The assessment also revealed a probable association between blood mercury level and eosinophilia. The same association was also seen between high mercury levels and the presence of tremors and working in the mercury mine. To date, there are very limited environmental and health studies on the impact of both total and methylmercury that have been undertaken in the Philippines. Thus, this area of study was selected primarily because of its importance as an emerging issue in the country, especially regarding the combined effects of total and methylmercury low-dose and continuous uptake from environmental sources. At present the effects of total mercury exposure combined with MeHg consumption remain an important issue, especially those of low-dose and continuous uptake. Results of the study showed that four (4) species of fish, namely ibis, tabas, lapu-lapu and torsillo, had exceeded the recommended total mercury and methylmercury levels in fish (NV>0.5 microg/gf.w., NV>0.3 microg/gf.w., respectively). Saging and kanuping also exceeded the permissible levels for methylmercury. Total and methylmercury in canned fish, and total mercury in rice, ambient air and drinking water were within the recommended levels, however, additional mercury load from these sources may contribute to the over-all body burden of mercury among residents in the area. Surface water quality at the mining area, Honda Bay and during some monitoring periods at Palawan Bay exceeded total mercury standards (NV>0.002 ng/mL). Soil samples in two sites, namely Tagburos and Honda Bay, exceeded the EPA Region 9 Primary Remediation Goal recommended values for total mercury for residential purposes (NV>23 mg/kg). The hand to mouth activity among infants and children is another significant route for mercury exposure. Statistically significant results were obtained for infants when comparing the results after one year of monitoring for methylmercury levels in hair for both exposed and control sub-groups. Likewise, comparing the initial and final hair methylmercury levels among pregnant women/mothers in the exposed group showed statistically significant (p<0.05) results. Comparing the exposed and control sub-groups' mercury hair levels per sub-group showed statistically significant results among the following: (a) initial and final total mercury hair levels among children, (b) initial and final methylmercury hair levels among children, (c) final total mercury hair levels among pregnant women, (d) initial and final total mercury hair levels among mothers, and (e) initial and final methyl hair levels among mothers. 相似文献
565.
Monitoring and assessment of toxic metals in Gulf War oil spill contaminated soil using laser-induced breakdown spectroscopy 总被引:1,自引:0,他引:1
Laser-induced breakdown spectroscopy (LIBS) was applied for the detection of toxic metals in oil spill contaminated soil (OSCS).
The OSCS samples were collected from Khursania Saudi Arabia along the coast of Persian Gulf exposed to oil spills in 1991
Gulf war. Environmentally important elements like Aluminum Magnesium, Calcium, Chromium, Titanium, Strontium, Iron, Barium,
Sodium, potassium, Zirconium and Vanadium from the contaminated soil have been detected. Optimal experimental conditions for
analysis were investigated. The LIBS system was calibrated using standard samples containing these trace elements. The results
obtained using Laser-Induced Breakdown Spectroscopy (LIBS) were compared with the results obtained using Inductively Coupled
Plasma Emission Spectroscopy (ICP). The concentrations of some elements (Ba and Cr) were found higher than permissible safe
limits. Health risks associated with exposure to such toxic elements are also discussed. 相似文献
566.
对南山国家森林公园主要植被物种资源进行调查和区系结构研究。结果表明,南山国家森林公园森林覆盖率达73%,自然生态系统中目前已知的高等植物(藻菌、苔藓、地衣除外)共计有74科、251属、340种。构成镇江市区各类植被的优势成分共有约27种,其中东亚分布的种占55.6%,热带分布为主的植物占7.4%,连同东亚分布以及我国特有热带、亚热带分布为主的成分,一起可达88.9%。南山国家森林公园植被在区系组成上具有明显的亚热带特点,同时也反映出一定的过渡性,与江苏省森林木本植物区系分布特点基本一致。 相似文献
567.
在某化工企业厂界内及周边布设9个土壤点位,对其二噁英进行检测与分析,依据《污染场地风险评估技术导则》对土壤中二噁英进行健康风险评估。结果表明,9个土壤点位二噁英毒性当量浓度为3.72~20.3 pg/g,均值为9.1 pg/g,均处于安全水平;在经口摄入、皮肤接触和吸入土壤颗粒物3种暴露途径下,只有4#点位具有较低的致癌风险;4#点位代表的场地区域为风险不可接受的污染区域,基于致癌效应的土壤风险控制值为1.84×10-5mg/kg。提出,应尽快研究并制定土壤中二噁英的标准限值。 相似文献
568.
569.
孔昭音 《环境监测管理与技术》2000,12(4):39-40
就现行的某些环境保护国家标准中存在的问题,提出了在制定或修订标准时,所用术语表达应准确,数字表达应统一采用中文数字或统一采用阿拉伯数字、内容相关标准就叮关性和统一性的建议。 相似文献
570.
Kimmo Louekari R. Mäkelä-Kurtto P. Jousilahti 《Environmental Modeling and Assessment》2008,13(4):517-525
We have assessed the change of the dietary intake and the potential health risks of cadmium in Finland, assuming that a high
level of cadmium in fertilizers (138 mg Cd/kg P) would prevail for the next 100 years. Soil measurements and modelling were
used to derive the predicted level of cadmium in foods. In three important cultivars, wheat, potato and sugar beet, the cadmium
concentration would increase by 20–35%. Consequently, the average dietary intake of cadmium in Finland would increase from
7.9 to 10.0 μg/day, corresponding with the urinary level of about 0.2 μg/l, a level that has not been associated with effects
on the human health. However, in the risk group with 1) high dietary intake of cadmium, 2) elevated gastrointestinal absorption,
and 3) tobacco smoking, the estimated urinary level of cadmium would be 2.0 μg/l. Recent epidemiological studies have shown
that urinary level of 1–2 μg Cd/l is associated with an increased risk of bone demineralization and fractures, and 2–4 μg
Cd/l with pre-clinical kidney damage. People characterized by more than one of the above-mentioned risks factors, may develop
the adverse health effects at an old age, when cadmium has accumulated in the body. 相似文献