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41.
P K Ghosh L Philip M Bandyopadhyay 《Journal of environmental science and health. Part. B》2001,36(3):301-316
Performance of mixed microbial anaerobic culture in treating synthetic waste-water with high Chemical Oxygen Demand (COD) and varying atrazine concentration was studied. Performance of hybrid reactors with wood charcoal as adsorbent, with a dose of 10 g/l and 40 g/l, along with the microbial mass was also studied. All the reactors were operated in sequential mode with Hydraulic Retention Time (HRT) of 5 days. In all the cases, COD removal after 5 days was found to be above 81%. Initial COD was above 1,000 mg/l. From a hybrid reactor COD removal after 2 days was observed to be 90%. Atrazine reduction after 5 days by microbial mass alone was 43.8%, 40% and 33.2% with an initial concentration of 0.5, 1.0 and 2.0 mg/l respectively. MLSS on all the cases were almost same. Increasing MLSS concentration by about 2 fold did not increase the atrazine removal efficiency significantly. Maximum atrazine removal was observed to be 64% from the hybrid reactor with 10 g/l of wood charcoal and 69.4% from the reactor with 40 g/l of wood charcoal. Atrazine removal from the hybrid reactors after 15 days were observed to be 35.7% and 38.7%, which showed that the higher dose of wood charcoal in hybrid reactor did not improve the atrazine removal efficiency significantly. Specific methanogenic activity test showed no inhibitory effect of atrazine on methane producing bacteria. The performance of anaerobic microorganisms in removing atrazine with no external carbon source and inorganic nitrogen source was studied in batch mode. With an initial concentration of 1.0 mg/l, reduction of atrazine by the anaerobic microorganisms in absence of external carbon source after 35 days was observed to be 61.8% where as in absence of external carbon and inorganic nitrogen source the reduction was only 44.2% after 150 days. Volatilization loss of atrazine was observed to be insignificant. 相似文献
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Joke Muys Bettina Blaumeiser Yves Jacquemyn Claude Bandelier Nathalie Brison Saskia Bulk Patrizia Chiarappa Winnie Courtens Anne De Leener Marjan De Rademaeker Julie Désir Anne Destrée Koenraad Devriendt Annelies Dheedene Annelies Fieuw Erik Fransen Jean-Stéphane Gatot Philip Holmgren Mauricette Jamar Sandra Janssens Kathelijn Keymolen Damien Lederer Björn Menten Marije Meuwissen Benoit Parmentier Bruno Pichon Sonia Rombout Yves Sznajer Ann Van Den Bogaert Kris Van Den Bogaert Olivier Vanakker Joris Vermeesch Katrien Janssens 《黑龙江环境通报》2018,38(13):1120-1128
47.
Many problems and challenges of ecosystem management currently are driven by the rapid pace and spatial extent of landscape
change. Parks and reserves within areas of high human population density are especially challenged to meet the recreational
needs of local populations and to preserve valued environmental resources. The complex problem of managing multiple objectives
and multiple resources requires an enormous quantity of information, and conceptual models have been proposed as tools for
organizing and interpreting this information. Academics generally prefer a bottom-up approach to model construction that emphasizes
ecologic theory and process, whereas managers often use a top-down approach that takes advantage of existing information to
address more pragmatic objectives. The authors propose a formal process for developing, applying, and testing conceptual models
to be used in landscape monitoring that reconciles these seemingly opposing perspectives. The four-step process embraces the
role of hypothesis testing in the development of models and evaluation of their utility. An example application of the process
to a network of national parks in and around Washington, DC illustrates the ability of the approach to systematically identify
monitoring data that would both advance ecologic theory and inform management decisions. 相似文献
48.
Zoning and applying Limits of Acceptable Change (LAC) are two promising strategies for managing tourism in Marine Protected
Areas (MPAs). Typically, these management strategies require the collection and integration of ecological and socioeconomic
data. This problem is illustrated by a case study of Koh Chang National Marine Park, Thailand. Biophysical surveys assessed
coral communities in the MPA to derive indices of reef diversity and vulnerability. Social surveys assessed visitor perceptions
and satisfaction with conditions encountered on snorkelling tours. Notably, increased coral mortality caused a significant
decrease in visitor satisfaction. The two studies were integrated to prescribe zoning and “Limits of Acceptable Change” (LAC).
As a biophysical indicator, the data suggest a LAC value of 0.35 for the coral mortality index. As a social indicator, the
data suggest that a significant fraction of visitors would find a LAC value of under 30 snorkellers per site as acceptable.
The draft zoning plan prescribed four different types of zones: (I) a Conservation Zone with no access apart from monitoring
or research; (II) Tourism Zones with high tourism intensities at less vulnerable reefs; (III) Ecotourism zones with a social
LAC standard of <30 snorkellers per site, and (IV) General Use Zones to meet local artisanal fishery needs. This study illustrates
how ecological and socioeconomic field studies in MPAs can be integrated to craft zoning plans addressing multiple objectives. 相似文献
49.
Designing the Masoala National Park in Madagascar Based on Biological and Socioeconomic Data 总被引:3,自引:0,他引:3
Claire Kremen ‡ Vincent Razafimahatratra † R. Philip Guillery ‡ Jocelyn Rakotomalala § rew Weiss and Jean-Solo Ratsisompatrarivo§ 《Conservation biology》1999,13(5):1055-1068
Abstract: Conservation biologists have developed powerful tools for reserve selection and design over the past two decades, yet seldom are protected areas actually designed on scientific grounds. Using fundamental biological and socioeconomic principles of conservation science, we designed a new protected area and its multiple-use zone on the Masoala Peninsula in the humid forest zone of Madagascar. The explicit design criteria determined the data gathered for the work, which included (1) spatial distribution and quality of habitat, (2) the areas and species at greatest risk, (3) the relationship between environmental gradients and species distributions, (4) current and predicted human settlement and land and resource use, and (5) the economic potential of natural forest management as an alternative to deforestation. We used a geographic information system to integrate these data layers and applied the design criteria to develop a park proposal that balanced human and wildlife needs. The proposal won the approval of local residents, and a national decree in 1997 designated 2100 km2 of rainforest and three satellite marine reserves as the Masoala National Park, with a surrounding multiple-use zone of approximately 1000 km2 . The new park is Madagascar's largest protected area and protects more lowland (<400 m) humid forest habitat than the entire reserve system combined, a significant step forward in conserving a globally important ecoregion. Consideration of local needs and the national economy was a key element in gaining approval for the Masoala Park. Such an approach toward reserve design could be applied elsewhere to improve chances of establishing and maintaining protected areas over the long term. 相似文献
50.
E. Joanne Verweij Martine C. de Vries Esther J. Oldekamp Alex J. Eggink Dick Oepkes Femke Slaghekke Jochem K. H. Spoor Jan A. Deprest Jena L. Miller Ahmet A. Baschat Philip L. J. DeKoninck 《黑龙江环境通报》2021,41(8):949-956
Since the completion of the Management of Myelomeningocoele Study, maternal-fetal surgery for spina bifida has become a valid option for expecting parents. More recently, multiple groups are exploring a minimally invasive approach and recent outcomes have addressed many of the initial concerns with this approach. Based on a previously published framework, we attempt to delineate the developmental stage of the surgical techniques. Furthermore, we discuss the barriers of performing randomized controlled trials comparing two surgical interventions and suggest that data collection through registries is an alternative method to gather high-grade evidence. 相似文献