Development of termites severity probability map of futa campus area using geographical information system (GIS) technology

Environment, Development and Sustainability - Siting of buildings in rural urban development requires that the prevalence of termite activities is considered. The severity of termite activities...     

美国清洁能源的成本和效益

将从分析美国新能源战略的有效性和成本入手,梳理和评估美国政府的新能源方案,同时提出一些关于清洁能源的建议。选择了美国推广清洁能源行为作为对象来讨论,不仅因为美国是世界上最大的清洁能源和可再生能源的投资者,同时还强调美国在运行这一投资的时候并没有使用自由市场来推动,而是完全由政府买单和控制。具体要讨论的方案是：核清理;低收入家庭房屋保暖;先进的汽车电池（牵引）系统及组件;电动汽车补贴退税制度。通过对每个方案内容的阐述和成本、效益的分析,来评估这些方案是否是有价值的和值得继续的。最后的结论可以归纳为这些清洁能源实施项目非常低效,并且提出一系列的证据表明这些项目在没有政府巨额经费支持的情况下是无法继续的,同时表明在没有严格的项目完成日期、持续发生超过预算的额外支出的情况下,政府的支持计划很可能和初衷背道而驰     

Assessment of pathogenic bacteria in water and sediment from a water reservoir under tropical conditions (Lake Ma Vallée), Kinshasa Democratic Republic of Congo

This study was conducted to assess potential human health risks presented by pathogenic bacteria in a protected multi-use lake-reservoir (Lake Ma Vallée) located in west of Kinshasa, Democratic Republic of Congo (DRC). Water and surface sediments from several points of the Lake were collected during summer. Microbial analysis was performed for Escherichia coli, Enterococcus (ENT), Pseudomonas species and heterotrophic plate counts. PCR amplification was performed for the confirmation of E. coli, ENT, Pseudomonas spp. and Pseudomonas aeruginosa isolated from samples. The results reveal low concentration of bacteria in water column of the lake, the bacterial quantification results observed in this study for the water column were below the recommended limits, according to WHO and the European Directive 2006/7/CE, for bathing water. However, high concentration of bacteria was observed in the sediment samples; the values of 2.65?×?10³, 6.35?×?10³, 3.27?×?10³ and 3.60?×?10⁸ CFU g^?1 of dry sediment for E. coli, ENT, Pseudomonas spp. and heterotrophic plate counts, respectively. The results of this study indicate that sediments of the Lake Ma Vallée can constitute a reservoir of pathogenic microorganisms which can persist in the lake. Possible resuspension of faecal indicator bacteria and pathogens would affect water quality and may increase health risks to the population during recreational activities. Our results indicate that the microbial sediment analysis provides complementary and important information for assessing sanitary quality of surface water under tropical conditions.     

Collaborative Science, Policy Development and Program Implementation in the Transboundary Georgia Basin/Puget Sound Ecosystem

The transboundary Georgia Basin Puget Sound ecosystem is situated in the southwest corner of British Columbia and northwest comer of Washington State. While bountiful and beautiful, this international region is facing significant threats to its marine and freshwater resources, air quality, habitats and species. These environmental challenges are compounded by rapid population growth and attendant uiban sprawl. As ecosystem stresses amplified and partnerships formed around possible solutions, it became increasingly clear that the shared sustainability challenges in the Georgia Basin and Puget Sound required shared solutions. Federal, state and provincial institutional arrangements were made between jurisdictions, which formalized small scale interest in transboundary management of this ecosystem. Formal agreements, however, can only do so much to further management of an ecosystem that spans international boarders. A transboundary regional research meeting, the 2003 GB/PS Research Conference, opened the doors for large-scale informal cross-boarder cooperation and management. In addition to cooperation, continued efforts to stem toxic pollution, contain urban growth, and protect and restore ecosystems, require a commitment from scientists, educators and policy makers to better integrate research and science with decision-making.Former Director of Planning and of Special Projects in the British Columbia Ministry of Municipal Affairs.     

Organochlorine contamination in shorebirds from Washington state and the significance for their falcon predators

Arctic-breeding shorebirds collected in western Washington state during winter and spring, and a comparative sample collected in coastal California during the winter were analyzed for organochlorine contaminants to determine the potential impact of these residues on populations of peregrine falcons (Falco peregrinus) and merlins (F. columbarius) which prey upon shorebirds in western Washington. Dunlins (Calidris alpina), an important winter prey for falcons in western Washington, were collected between 1975 and 1981. During winter 1980–81, dunlins carried low organochlorine residues; DDE levels ranged from 0.01 to 1.2 ppm, and PCB levels ranged from 0.02 to 0.82 ppm (wet weight). Levels of other organochlorine contaminants (HCB, Chlordane compounds, Dieldrin, and Heptachlor Epoxide), analyzed in a subsample of dunlins, were consistently lower than DDE and PCB levels, and ranged from 0.001 to 0.22 ppm (wet weight). Dunlins in western Washington did not significantly increase their DDE or PCB burdens over the 1980–81 winter. A decline in DDE residues between 1978 and 1981 was noted, and declines in PCB residues from both 1975 and 1978 to 1980–81 were noted. Residues in other wintering shorebirds from western Washington were similar. Wintering sanderlings (Calidris alba) from California, revealed much higher DDE contamination than in Washington (up to 32 ppm, wet weight). Spring migrant shorebirds in western Washington contained both low and very high DDE residues (up to 417 ppm, wet weight). There is evidence suggesting these high DDE concentrations are accumulated along the Pacific coast of North America.     

Geospatial Analysis of Climatic and Geomorphic Interactions Influencing Stream Discharge, Appalachian Mountains, USA

Streamflow values are commonly synthesized for locations where flow measurement stations are lacking or where only intermittent measurements are available. In an Appalachian Mountains dataset comprised of 29 watersheds, the most appropriate among geomorphic, geologic, and hydrogeologic datasets were selected for use in prediction of streamflow at watershed scale. A statistical model was developed using principal components analysis (PCA) and cluster analysis (CA) for. Using CA on variables derived from the PCA, an optimum set of variables was derived for predicting streamflow. Results indicate there are two categories of watersheds in the study area. The first is strongly correlated with climatic variables (precipitation, temperature, elevation, and groundwater recharge). The second is strongly correlated with two geomorphic variables (watershed slope and percentage of forested area). The spatial distribution of cluster classifications shows that watersheds dominated by the climatic component are located along the Allegheny Front while watersheds dominated by the geomorphic component are located in the Allegheny Plateau and Valley and Ridge physiographic provinces. These variations between the Allegheny Plateau and Valley and Ridge physiographic provinces suggest that, to accurately model streamflow, modeling needs be done based on natural physiographic boundaries rather than political boundaries. In this physiographic setting, elevation seems to be a major control.     

A remote in situ monitor based on continuous flow analysis for the quantitation of sub-micromolar levels of hexavalent chromium in natural waters

We describe the design, optimization, and application of a small, lightweight, deployable monitoring instrument for accurately measuring parts-per-billion levels of hexavalent Cr in surface waters at hourly intervals. The monitor quantifies Cr(vi) using a standard molecular absorbance spectroscopic method, i.e. by formation of a complex with 1,5-diphenylcarbazide (DPC). The continuous flow analysis (CFA) design uses narrow conduits (0.90 mm) that are hot-forged onto poly(methyl methacrylate) ('Plexiglas') plates based on the method of Jannasch et al.(Anal. Chem., 1994, 66, 3352). The sample stream is drawn through the manifold at 25 microl min(-1) using a mini-peristaltic pump; osmotic pumps (10 microl h(-1)) are used to continuously inject reagent (2.0 mM DPC, 0.60 M HNO(3), 5.0% w/v acetone, and 0.10% w/v Brij-35) and to periodically introduce quality control standards and a cleaning solution (0.50 M HNO(3)). The 'Z-type' optical cell uses a liquid-core waveguide (10 mm) to collimate the light-emitting diode source beam (lambda(max) 574 nm) to a broadband photodiode detector. Figures of merit are: 7 min cycle time, response within 28 min and clear-down within 31 min, low waste generation (<40 ml d(-1)), detection limit (3sigma) of 48.4 microg l(-1) as Cr(vi) or 0.411 microM as chromic acid, 1.54% relative standard deviation at 100 microg l(-1), and selectivity for dissolved Cr(vi) in authentic surface water samples containing moderate levels (>0.21% w/v) of total particulate matter. Using a test chamber containing Milwaukee Harbor water that was periodically fortified with Cr(vi) standards, continuous testing over a 15 day period (354 h) yielded results that were in excellent agreement (<5% variation) with measurements made using an ICP-MS reference method. Drift in the calibration model over the test period was 1.23% and the variation in a 0.50 mg l(-1) Cr(vi) standard was 3.8%(n= 11). Known interferences to the DPC chemistry (Mo, V, and Hg at >5 mg l(-1)) were undetected in the harbor water by ICP-MS.     

A Data-Based Conservation Planning Tool for Florida Panthers

Habitat loss and fragmentation are the greatest threats to the endangered Florida panther (Puma concolor coryi). We developed a data-based habitat model and user-friendly interface so that land managers can objectively evaluate Florida panther habitat. We used a geographic information system (GIS) and the Mahalanobis distance statistic (D ²) to develop a model based on broad-scale landscape characteristics associated with panther home ranges. Variables in our model were Euclidean distance to natural land cover, road density, distance to major roads, human density, amount of natural land cover, amount of semi-natural land cover, amount of permanent or semi-permanent flooded area–open water, and a cost–distance variable. We then developed a Florida Panther Habitat Estimator tool, which automates and replicates the GIS processes used to apply the statistical habitat model. The estimator can be used by persons with moderate GIS skills to quantify effects of land-use changes on panther habitat at local and landscape scales. Example applications of the tool are presented.     

An ecosystem report on the Panama Canal: monitoring the status of the forest communities and the watershed

In 1996, the Smithsonian Tropical Research Institute and the Republic of Panama's Environmental Authority, with support fromthe United States Agency for International Development, undertook a comprehensive program to monitor the ecosystem of the Panama Canal watershed. The goals were to establish baselineindicators for the integrity of forest communities and rivers. Based on satellite image classification and ground surveys, the2790 km² watershed had 1570 km² of forest in 1997, 1080 km² of which was in national parks and nature monuments. Most of the 490 km² of forest not currently in protected areas lies along the west bank of the Canal, and its managementstatus after the year 2000 turnover of the Canal from the U.S. to Panama remains uncertain. In forest plots designed to monitorforest diversity and change, a total of 963 woody plant specieswere identified and mapped. We estimate there are a total of 850–1000 woody species in forests of the Canal corridor. Forestsof the wetter upper reaches of the watershed are distinct in species composition from the Canal corridor, and have considerably higher diversity and many unknown species. Theseremote areas are extensively forested, poorly explored, and harbor an estimated 1400–2200 woody species. Vertebrate monitoring programs were also initiated, focusing on species threatened by hunting and forest fragmentation. Large mammals are heavily hunted in most forests of Canal corridor, and therewas clear evidence that mammal density is greatly reduced in hunted areas and that this affects seed predation and dispersal. The human population of the watershed was 113 000 in 1990, and grew by nearly 4% per year from 1980 to 1990. Much of this growth was in a small region of the watershed on the outskirts of Panama City, but even rural areas, including villages near and within national parks, grew by 2% per year. There is no sewage treatment in the watershed, and many towns have no trashcollection, thus streams near large towns are heavily polluted. Analyses of sediment loads in rivers throughout the watershed did not indicate that erosion has been increasing as a result ofdeforestation, rather, erosion seems to be driven largely by total rainfall and heavy rainfall events that cause landslides.Still, models suggest that large-scale deforestation would increase landslide frequency, and failure to detect increases inerosion could be due to the gradual deforestation rate and the short time period over which data are available. A study of runoff showed deforestation increased the amount of water fromrainfall that passed directly into streams. As a result, dry season flow was reduced in a deforested catchment relative to aforested one. Currently, the Panama Canal watershed has extensive forest areasand streams relatively unaffected by humans. But impacts of hunting and pollution near towns are clear, and the burgeoningpopulation will exacerbate these impacts in the next few decades.Changes in policies regarding forest protection and pollution control are necessary.