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51.
Huntington HP Brown-Schwalenberg PK Frost KJ Fernandez-Gimenez M Norton DW Rosenberg DH 《Environmental management》2002,30(6):0778-0792
Traditional ecological knowledge (TEK) and the information and insights it offers to natural resource research and management
have been given much attention in recent years. On the practical question of how TEK is accessed and used together with scientific
knowledge, most work to date has examined documentation and methods of recording and disseminating information. Relatively
little has been done regarding exchanges between scientific and traditional knowledge. This paper examines three workshop
settings in which such exchanges were intended outcomes. The Barrow Symposium on Sea Ice, the Exxon Valdez Oil Spill Restoration Program Synthesis/Information Workshops, and the Alaska Beluga Whale Committee illuminate certain features
of the preparation, format, and context of workshops or series of workshops and their eventual outcomes and influence. The
examples show the importance of long-term relationships among participants and thorough preparation before the actual workshop.
Further research should look more systematically at the factors that influence the success of a given workshop and the various
ways in which participants perceive success. 相似文献
52.
Extracts of 19 of 24 species of sponge collected from Queensland. Australia, inhibited the growth of test microorganisms in in-vitro assays. A similar result has been obtained by earlier workers for extracts of species of sponge obtained from temperate waters. Some of the extracts, including extracts of Thorecta vasiforis, Arenochalina mirabilis and Acanthella kleutha, showed activity against bacterial strains that was comparable with that exhibited by penicillin G and streptomycin against these strains. Gram-positive bacteria were expecially sensitive to many extracts. Little activity was exhibited by any extract against four species of fungi tested. Some of the extracts were markedly toxic to one or more of the test organisms (a fish, a crustacean and a hydroid) used, but no clear pattern linking toxicity to these organisms with antimicrobial properties of the extracts emerged. In general, there bas a negative correlation between antimicrobial activity and surface-fouling, raising the possibility of using freedom from surface-fouling as an indicator of antimicrobial activity. Four of five encrusting species from the undersides of coral boulders showed antimicrobial activity. This study confirmed the value of using methanol-toluene extracts in field-based screening programmes, but emphasised the need to use additional extracting media such as methylene chloride in order to augment the number of antimicrobial compounds detected. There are indications that antimicrobial activity may be widespread in the order Dictyoceratida, in the order Verongida and in the order Axinellida, but sporadic in other orders of Porifera. 相似文献
53.
Rough Set Rule Induction for Suitability Assessment 总被引:4,自引:0,他引:4
Berger PA 《Environmental management》2004,34(4):546-558
The data that characterize an environmental system are a fundamental part of an environmental decision-support system. However, obtaining complete and consistent data sets for regional studies can be difficult. Data sets are often available only for small study areas within the region, whereas the data themselves contain uncertainty because of system complexity, differences in methodology, or data collection errors. This paper presents rough-set rule induction as one way to deal with data uncertainty while creating predictive if–then rules that generalize data values to the entire region. The approach is illustrated by determining the crop suitability of 14 crops for the agricultural soils of the Willamette River Basin, Oregon, USA. To implement this method, environmental and crop yield data were spatially related to individual soil units, forming the examples needed for the rule induction process. Next, four learning algorithms were defined by using different subsets of environmental attributes. ROSETTA, a software system for rough set analysis, was then used to generate rules using each algorithm. Cross-validation analysis showed that all crops had at least one algorithm with an accuracy rate greater than 68%. After selecting a preferred algorithm, the induced classifier was used to predict the crop suitability of each crop for the unclassified soils. The results suggest that rough set rule induction is a useful method for data generalization and suitability analysis. 相似文献
54.
Almeida CA Quintar S González P Mallea MA 《Environmental monitoring and assessment》2007,133(1-3):459-465
A study of the water quality of the Potrero de los Funes River (San Luis – Argentina) was carried out in order to evaluate
the possible effect of the anthropogenic activities on the river developed in the homonymous town. Samples were collected
during the period March 2000–November 2005 at three selected sampling sites (RP1, RP2 and RP3). Different physicochemical and bacteriological parameters (turbidity, pH, conductivity, suspended solids, alkalinity, potassium,
sodium, calcium, magnesium, chlorides, nitrates, phosphates, sulphates, chemical oxygen demand (COD), 5-day biological oxygen
demand (BOD5), dissolved oxygen, total coliforms, Escherichia coli and total heterotrophic bacteria) were analysed according to the Standard Method for the Examination of Water and Wastewater.
When comparing the values of total coliforms, E. coli, total heterotrophic bacteria, COD, BOD5 and phosphates from the zone without anthropogenic influence (RP1) and the urban zones (RP2 and RP3) an important variation in the parameters was observed. These results indicate that the urban activity produces a serious
and negative effect on the water quality, thus constituting a sanitary risk and may have a major impact on the trophic status
of the Potrero de los Funes dam. As case study, we report on the use of General Quality Index (GQI) to evaluate spatial and
seasonal changes in the water quality of Potrero de los Funes River. Results revealed a significant degradation of the water
quality at RP2 and RP3. 相似文献
55.
Patricia A Orosz-Coghlan Patricia A Rusin Martin M Karpiscak Charles P Gerba 《Water environment research》2006,78(3):227-232
Little information has been gathered on the effect of avian species on the microbial water quality in constructed wetlands. To address this concern, fecal pollution from nonpoint and point sources was evaluated in a constructed wetland in Tolleson, Arizona. Antibiotic resistance profiling and biochemical fingerprinting were performed on 325 Escherichia coli isolates, collected from key points in the wetlands. Multivariate statistical analysis was used to interpret the data for samples collected on October 3 and December 12, 2000, and January 16, 2001. It was found that the passerine population was the major source of the Escherichia coli in the water samples collected in the wetlands on October 3 and December 12, 2000, whereas the regrowth in the treated municipal wastewater was the main source on January 16, 2001. This information is useful in providing data for operators in the monitoring of wetlands created for wastewater treatment and wildlife habitat. 相似文献
56.
Enrique Isla Elisabet Sañé Patricia Homs Nùria Teixidó Rubén Escribano 《Chemistry and Ecology》2013,29(2):123-140
Seasonal differences in the concentration and biochemical composition of seston have been assessed for the first time in the Humboldt Current System off northern Chile (21°S). The study comprised four seasonal surveys in the Bay of Chipana, including the summer and winter of 2006 and 2007, when El Niño 2006 and La Niña 2007 developed. Protein, lipid, carbohydrate and biogenic silica contents were measured in samples collected at four selected depths. The highest protein, lipid and carbohydrate concentrations were found at the fluorescence maximum (between 10 and 15 m depth), whereas the highest biogenic silica concentration was found 1 m above the seabed. When El Niño started developing, every variable showed low values throughout the water column; however, the lowest values were found when La Niña conditions dominated, together with low oxygen concentrations. Samples collected within the oxygen minimum zone (65 m depth) showed the lowest values for the water column and the lowest seasonal variations. After the evident decline coincident with El Niño 2006, the abundance and biochemical quality (high protein and lipid contents) of seston recovered earlier in the surface layer (upper 15 m) than at other depths. 相似文献
57.
Community metabolism in a deep (stratified) tropical reservoir during a period of high water-level fluctuations 总被引:2,自引:0,他引:2
Patricia M. Valdespino-Castillo Martín Merino-Ibarra Jorge Jiménez-Contreras Fermín S. Castillo-Sandoval Jorge A. Ramírez-Zierold 《Environmental monitoring and assessment》2014,186(10):6505-6520
As long as lakes and reservoirs are an important component of the global carbon cycle, monitoring of their metabolism is required, especially in the tropics. In particular, the response of deep reservoirs to water-level fluctuations (WLF) is an understudied field. Here, we study community metabolism through oxygen dynamics in a deep monomictic reservoir where high WLF (~10 m) have recently occurred. Simultaneous monitoring of environmental variables and zooplankton dynamics was used to assess the effects of WLF on the metabolism of the eutrophic Valle de Bravo (VB) reservoir, where cyanobacteria blooms are frequent. Mean gross primary production (P g) was high (2.2 g C m?2 day?1), but temporal variation of P g was low except for a drastic reduction during circulation attributed to zooplankton grazing. The trophogenic layer showed net autotrophy on an annual basis, but turned to net heterotrophy during mixing, and furthermore when the whole water-column oxygen balance was calculated, considering the aphotic respiration (R aphotic). The high total respiration resulting (3.1 g C m?2 day?1) is considered to be partly due to mixing enhanced by WLF. Net ecosystem production was equivalent to a net export of 3.4 mg CO2?m?2 day?1 to the atmosphere. Low water levels are posed to intensify boundary-mixing events driven by the wind during the stratification in VB. Long-term monitoring showed changes in the planktonic community and a strong silicon decrease that matched with low water-level periods. The effects of low water-level on metabolism and planktonic community in VB suggest that water-level manipulation could be a useful management tool to promote phytoplankton groups other than cyanobacteria. 相似文献
58.
Goemeone E. J Mogomotsi Patricia K Mogomotsi Reniko Gondo Tshenolo J Madigele 《中国人口.资源与环境(英文版)》2018,16(2):171-180
Cultural heritage does not have direct economic benefits. However, if properly managed it can stimulate social cohesions, improving the environment and have beneficial economic spin offs for the local communities. This paper discusses the role of communities in the formulation of the policies concerning their local environment. It argues that community engagement by policy makers is important in giving legitimacy and ownership of the policies. Furthermore, this paper discusses the potential of cultural heritage in diversifying the economy in Botswana. This paper recommends for the re-assessment of the relationship between the state and local communities which is critical in resuscitating the seemingly ailing community business organizations. In conclusion, it argues for the sustainable management of cultural heritage as a social and economic resource in the next 50 years of Botswana’s independence. 相似文献
59.
Patricia Barnett 《生态毒理学报》2002,(4):18-19
旅游业关注组织 ( Tourism Concern) 意识到在必然的旅游程序中 , 存在着一连串错误的解释 , 它们都在暗示自己才是旅游开发所产生问题的解决方案 . 就我们所见 , 它们被冠以的名目 有 : “ 责任心之旅 “ 、 “ 绿色之旅 “ 、 “ 亲近贫困之旅 “ 、 “ 民俗特色之旅 “ 、 “ 社区之旅 “ 、 “ 生态之旅 “ 等等 , 不一而足 . 它们把我们的视线从关注真正的需求 , 切换到旅游结构 与发展中基本原则的改变 .
…… 相似文献
60.
Patricia Cortijo 《生态毒理学报》2004,(3):28
ACCor是欧洲最大的旅行、旅游和团体服务集团.它有150000名员工,分布在140个国家.将近有4000个Accor旅馆(443000个房间)分布在90个国家.…… 相似文献