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171.
Kirk R. Smith 《Environmental management》1986,10(1):61-74
About half the world's households cook and/or heat daily with biomass fuels. At small scale, biomass combustion releases significant amounts of particulates, carbon monoxide, and hydrocarbons, the latter with significant concentrations of polycyclic aromatic hydrocarbons. Preliminary measurements in kitchens of developing-country villages have established airborne concentrations of these healthdamaging pollutants that are orders of magnitude above urban levels or relevant standards. Particle size measurements and dose calculations lead to significant concerns about potential health hazards. The few epidemiological studies are consistent with such effects although more work is clearly needed. These findings may have significant implications for the planning of rural energy development in a number of countries. In particular, they may relate directly to the question of the optimum balance between centralized and decentralized systems. 相似文献
172.
Charles A. Whitehurst Elvin J. Dantin Donald Harang 《Journal of the American Water Resources Association》1975,11(4):734-750
ABSTRACT: The Louisiana Environmental Management System (LEMS) is a data processing program developed to aid the Louisiana Joint Legislative Committee on Environmental Quality in decisions leading to resources legislation. Serving as a central data collection and retrieval point for various agencies, the LEMS will maintain assembled information on the location of monitoring stations and coordinate the files of user agencies with data on: land use; air and water quality; meteorological, climatological, and hydrological phenomena; vegetation; fish and wildlife conservation; population; and economics. This data is geographically stored in relation to the state plane coordinate system. For decision making, all pertinent hydrologic, topographic, engineering, cadastral, and other information from separate sources can be automatically mapped as a combined overlay to one of three chosen scales. Land-use patterns are the input data for iterative analyses of present conditions and simulated future human activities for assessing the environmental impact of proposed multiple-purpose water resource developments. 相似文献
173.
174.
NACHIKET KELKAR JAGDISH KRISHNASWAMY SUNIL CHOUDHARY DIPANI SUTARIA 《Conservation biology》2010,24(4):1130-1140
Abstract: Freshwater biodiversity conservation is generally perceived to conflict with human use and extraction (e.g., fisheries). Overexploited fisheries upset the balance between local economic needs and endangered species’ conservation. We investigated resource competition between fisheries and Ganges river dolphins (Platanista gangetica gangetica) in a human‐dominated river system in India to assess the potential for their coexistence. We surveyed a 65‐km stretch of the lower Ganga River to assess habitat use by dolphins (encounter rates) and fishing activity (habitat preferences of fishers, intensity of net and boat use). Dolphin abundance in the main channel increased from 179 (SE 7) (mid dry season) to 270 (SE 8) (peak dry season), probably as a result of immigration from upstream tributaries. Dolphins preferred river channels with muddy, rocky substrates, and deep midchannel waters. These areas overlapped considerably with fishing areas. Sites with 2–6 boats/km (moderately fished) were more preferred by dolphins than sites with 8–55 boats/km (heavily fished). Estimated spatial (85%) and prey–resource overlap (75%) between fisheries and dolphins (chiefly predators of small fish) suggests a high level of competition between the two groups. A decrease in abundance of larger fish, indicated by the fact that small fish comprised 74% of the total caught, may have intensified the present competition. Dolphins seem resilient to changes in fish community structure and may persist in overfished rivers. Regulated fishing in dolphin hotspots and maintenance of adequate dry season flows can sustain dolphins in tributaries and reduce competition in the main river. Fish‐stock restoration and management, effective monitoring, curbing destructive fishing practices, secure tenure rights, and provision of alternative livelihoods for fishers may help reconcile conservation and local needs in overexploited river systems. 相似文献
175.
Khamphe PHOUNGTHONG Yi XIA Hua ZHANG Liming SHAO Pinjing HE 《Frontiers of Environmental Science & Engineering》2016,10(2):399
The continuously increasing production of municipal solid waste incineration bottom ash (MSWIBA) has promoted its utilization as construction material and raised environmental concern. The physico-chemical properties and leaching behavior of MSWIBA were studied, and ecotoxicological testing using a luminescent bacterium bioassay was performed to assess the ecological pollution risks associated with its leached constituents. The MSWIBA was leached by two types of leachants, H2SO4/HNO3 and HAc solution, at different liquid to solid ratios and contact times. The concentrations of heavy metals and anions in the leachates were analyzed. Multivariate statistical analyses, including principle component analysis, Pearson's correlation analysis and hierarchical cluster analysis, were used to evaluate the contributions of the constituents to the toxicity (EC50) of the MSWIBA leachate. The statistical analyses of the ecotoxicological results showed that the Ba, Cr, Cu, Pb, F− and total organic carbon (TOC) concentrations were closely correlated with the EC50 value, and these substances were the main contributors to the ecotoxicity of the MSWIBA leachate. In addition, the cluster of these variables indicated similar leaching behaviors. Overall, the research demonstrated that the ecotoxicological risks resulting from MSWIBA leaching could be assessed before its utilization, which provides crucial information for the adaptation of MSWIBA as alternative materials. 相似文献
176.
James G. C. Ball Mark A. Burgman Elizabeth D. Goldman Janeth Lessmann 《Conservation biology》2021,35(1):263-273
In pursuit of socioeconomic development, many countries are expanding oil and mineral extraction into tropical forests. These activities seed access to remote, biologically rich areas, thereby endangering global biodiversity. We examined how protection of biodiversity and economic revenues can be balanced in biologically valuable regions. Using spatial data on oil profits and predicted species and ecosystem extents, we optimized the protection of 741 terrestrial species and 20 ecosystems of the Ecuadorian Amazon across a range of opportunity costs (i.e., sacrifices of extractive profit). We also applied spatial statistics to remotely sensed, historic deforestation data to focus the optimization on areas most threatened by imminent forest loss. Giving up 5% of a year's oil profits (US$221 million) allowed for a protected area network that retained an average of 65% of the extent of each species and ecosystem. This performance far exceeded that of the network produced by simple optimization for land area (which required a sacrifice of approximately 40% of annual oil profits [US$1.7 billion]) and used only marginally less land to achieve equivalent levels of ecological protection. We identified what we call emergency conservation targets: regions that are essential components of a cost-effective conservation reserve network but at imminent risk of destruction, thus requiring urgent and effective protection. Governments can use our methods when evaluating extractive-led development options to responsibly manage the associated ecological and economic trade-offs and protect natural capital. 相似文献
177.
The interaction between seaweed farming as an alternative occupation and fisher numbers in the central Philippines 总被引:1,自引:0,他引:1
Alternative occupations are frequently promoted as a means to reduce the number of people exploiting declining fisheries. However, there is little evidence that alternative occupations reduce fisher numbers. Seaweed farming is frequently promoted as a lucrative alternative occupation for artisanal fishers in Southeast Asia. We examined how the introduction of seaweed farming has affected village-level changes in the number of fishers on Danajon Bank, central Philippines, where unsustainable fishing has led to declining fishery yields. To determine how fisher numbers had changed since seaweed farming started, we interviewed the heads of household from 300 households in 10 villages to examine their perceptions of how fisher numbers had changed in their village and the reasons they associated with these changes. We then asked key informants (people with detailed knowledge of village members) to estimate fisher numbers in these villages before seaweed farming began and at the time of the survey. We compared the results of how fisher numbers had changed in each village with the wealth, education, seaweed farm sizes, and other attributes of households in these villages, which we collected through interviews, and with village-level factors such as distance to markets. We also asked people why they either continued to engage in or ceased fishing. In four villages, respondents thought seaweed farming and low fish catches had reduced fisher numbers, at least temporarily. In one of these villages, there was a recent return to fishing due to declines in the price of seaweed and increased theft of seaweed. In another four villages, fisher numbers increased as human population increased, despite the widespread uptake of seaweed farming. Seaweed farming failed for technical reasons in two other villages. Our results suggest seaweed farming has reduced fisher numbers in some villages, a result that may be correlated with socioeconomic status, but the heterogeneity of outcomes is consistent with suggestions that alternative occupations are not a substitute for more direct forms of resource management. 相似文献
178.
Landfill gas (LFG) utilization which means a synergy between environmental protection and bioenergy recovery was investigated in this study. Pressure swing adsorption technology was used in LFG purification, and laboratory experiment, pilot-scale test, and on-site demonstration were carried out in Shenzhen, China. In the laboratory experiment, A-type carbon molecular sieve was selected as the adsorbent by comparison of several other adsorbents. The optimal adsorption pressure and adsorption time were 0.25 MPa and 2 min, respectively, under which the product generation rate was 4.5 m3/h and the methane concentration was above 90%. The process and optimization of the pilot-scale test were also reported in the paper. The product gas was of high quality compared with the National Standard of Compressed Natural Gas as Vehicle Fuel (GB18047-2000), when the air concentration in feed gas was under 10.96%. The demonstration project was composed of a collection system, production system, and utilization system. The drive performance, environmental protection performance, and economic feasibility of the product gas — as alternative fuel in passenger car, truck, and bulldozer—were tested, showing the feasibility technology for LFG utilization. 相似文献
179.
白洋淀芦苇型水陆交错带水化学动态及其净化功能研究 总被引:4,自引:0,他引:4
于2007年3月-11月对富营养化湖泊一白洋淀进行了现场调查,分析了温度、溶解氧(DO)、叶绿素、总磷(TP)及其他水化学指标的动态变化规律,并讨论了它们之间的相互关系。结果表明:白洋淀芦苇(Phragmites australis var.baiyangdiansis)型水陆交错带对营养物质具有强烈的截留作用,可以达到净化白洋淀水体的效果。从水质指标的空间分布看,污染较重的府河河口区域其水体TP、化学需氧量(CODc,)含量明显高于污染较轻的湖泊中心区域,空间梯度上呈逐步递减趋势。根据水体盐度、总溶解性固体、TP及DO含量进行聚类分析,可以将采样点分为3类:Ⅰ区、污染较重河口区域;Ⅱ区、中间过渡缓冲区域;Ⅲ区、污染较轻中心区域。Ⅰ区其水体DO含量明显低于Ⅲ区,而水体盐度则明显高于Ⅲ区。通过调查发现:在8月份,白洋淀水体DO含量突然增加;相关分析表明:叶绿素含量与DO(P=0.046)及温度(P〈0.01)之间呈显著正相关关系。结合叶绿素等指标的动态变化规律,8月份左右可能是白洋淀藻类爆发的危险时期。 相似文献
180.
Gary Comstock 《Journal of Agricultural and Environmental Ethics》1990,3(2):114-146
Should we continue to support publicly funded research on genetically engineered herbicide resistant crops? In Part One, I discussed the difference between science and ethics, presented a brief history of weed control, and explained three moral principles undergirding my environmentalist perspective. I then argued that unqualified endorsement (E) of the research is unjustified, as is unqualified opposition (O). In Part Two, I argue against qualified endorsement (QE), and for qualified opposition (QO). 相似文献