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851.
Polymorphism in soft coral larvae revealed by amplified fragment-length polymorphism (AFLP) markers 总被引:2,自引:0,他引:2
The dioecious Red Sea soft coral Parerythropodium fulvum fulvum breeds its nonsymbiotic planula larvae on the surface of female colonies for less than a week. After completing their development,
larvae crawl and settle near maternal colonies. Here we study the genetic polymorphism of developing larvae by the use of
amplified fragment-length polymorphism markers. Four reproductive colonies from shallow water populations (two from a dense
population and two from a less densely populated area 100 m away) were chosen, and ten larvae were randomly collected from
each colony. DNA was analyzed by using three different primer combinations producing 61, 63, 63 polymorphic markers, respectively.
All larvae exhibited different banding patterns from one another, illustrating the prominent role of sexual reproduction for
the production of larvae. Nei's mean genetic distances for all 12 possible pair-wise combinations for larval origins revealed,
in most cases, that sister larvae are genetically closer than larvae from different colonies and that larvae may be grouped
into three statistical clusters in accordance with colony origin and population studied. The usefulness of molecular methodologies
in coral population genetics is discussed.
Received: 26 March 1999 / Accepted: 19 October 1999 相似文献
852.
Paulo Ribeiro Fernando Fonseca Carolina Neiva Tiziana Bardi Júlia M. Lourenço 《Journal of Environmental Planning and Management》2018,61(2):195-213
This paper describes an integrated approach to transform an industrial park into an eco-industrial park by combining three interconnected goals, namely, the consolidation of industrial symbiosis, the promotion of sustainable accessibility and the development of multi-functionalities. The result is an interdependent approach where industrial and territorial ecosystems are jointly planned, seeking a more sustainable level of development that considers industrial activity, the transportation of people and goods and the spatial articulation with the neighbouring environment and urban areas. The critical points and challenges for improving the territorial integration of the French industrial park of Salaise-Sablons are discussed, providing lessons for the future. Regardless of the specificities of the case study, this approach has the potential to be adopted in similar industrial parks. 相似文献
853.
Associations between Water Physicochemistry and Prymnesium parvum Presence,Abundance, and Toxicity in West Texas Reservoirs
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Matthew M. VanLandeghem Mukhtar Farooqi Greg M. Southard Reynaldo Patiño 《Journal of the American Water Resources Association》2015,51(2):471-486
Toxic blooms of golden alga (Prymnesium parvum) have caused substantial ecological and economic harm in freshwater and marine systems throughout the world. In North America, toxic blooms have impacted freshwater systems including large reservoirs. Management of water chemistry is one proposed option for golden alga control in these systems. The main objective of this study was to assess physicochemical characteristics of water that influence golden alga presence, abundance, and toxicity in the Upper Colorado River basin (UCR) in Texas. The UCR contains reservoirs that have experienced repeated blooms and other reservoirs where golden alga is present but has not been toxic. We quantified golden alga abundance (hemocytometer counts), ichthyotoxicity (bioassay), and water chemistry (surface grab samples) at three impacted reservoirs on the Colorado River; two reference reservoirs on the Concho River; and three sites at the confluence of these rivers. Sampling occurred monthly from January 2010 to July 2011. Impacted sites were characterized by higher specific conductance, calcium and magnesium hardness, and fluoride than reference and confluence sites. At impacted sites, golden alga abundance and toxicity were positively associated with salinity‐related variables and blooms peaked at ~10°C and generally did not occur above 20°C. Overall, these findings suggest management of land and water use to reduce hardness or salinity could produce unfavorable conditions for golden alga. 相似文献
854.
Pinheiro MC Crespo-López ME Vieira JL Oikawa T Guimarães GA Araújo CC Amoras WW Ribeiro DR Herculano AM do Nascimento JL Silveira LC 《Environment international》2007,33(1):56-61
Mercury is a hazardous metal responsible for environmental contamination and human intoxication. Methylmercury, a very toxic organic compound, bio-accumulates through food chain, and is responsible for chronic mercury exposure of riverside Amazonian communities with a diet rich in fish. Uncertainties about the reference exposure dose that could have damaging consequences for nervous system development makes necessary the biomonitoring of these Amazonian populations, especially children. In this work, a comparative study was performed in exposed and non-exposed children living in the Amazon. A total of 168 children were analyzed to find possible correlations between gender, age, location, and hair mercury content. For each location, no statistically significant differences (P<0.05) were detected for gender and age versus mercury content. However, mean mercury levels in hair samples may indicate a tendency of boys to average higher hair concentrations. Also, in the community with highest levels of mercury, the limit of 10 micro g/g of mercury was surpassed by 65% of 2-6 years and 50% of 7-12 years children but only by 27% of 0-1 year babies, pointing to a lower bioaccumulation and/or the existence of a protection mechanism in babies. Log normal distributions of mercury concentrations for each location showed that children from populations under influence of gold mining activity contain the highest mercury levels in hair samples, though this intoxication may have decreased when compared to previous studies. Knowledge originated by this monitoring will better assist in the development of prevention strategies and government actions targeting the mercury contamination of Amazonian environment. 相似文献
855.
Célia M. Teixeira Rita Gamito Francisco Leitão Henrique N. Cabral Karim Erzini Maria J. Costa 《Regional Environmental Change》2014,14(2):657-669
Fisheries are an important source of food, with a high economic value and social significance. The present worrying situation of the world fisheries is the result of the interaction between different factors (e.g. climatic variations, natural oscillations, technological innovation), but the greatest challenges are overfishing and climate change. The species richness of the Portuguese coast is generally higher than that found in northern Europe and similar to that of the Mediterranean, since many species have their southern or northern distribution limits along the Portuguese coast. The zoogeographic importance of this latitudinal area has long been recognized, representing the transition between north-eastern Atlantic warm-temperate and cold-temperate regions, which makes the Portuguese coast an area of great sensitivity to the detection of climate change. Official landing data for commercial species that have the Portuguese coast as their distribution limit were analysed together with sea surface temperature for the period of 1927–2011. In general, landings of species with affinity for temperate waters presented a decreasing trend, whereas species with affinity for subtropical/tropical waters showed an increasing trend. These variations were associated with variation in temperature: lower landings of temperate species occurred mainly in warm years, whereas landings of subtropical/tropical species presented an opposite trend, with higher landings in warm years. Preparing for the impacts of climate change is crucial for the sustainability of fisheries. Management should take into consideration information about environmental factors that affect species distribution and abundance. 相似文献
856.
Ana Mendon?a Concei??o Juana Fortes Rui Capit?o Maria da Gra?a Neves Theo Moura José Sim?o Antunes do Carmo 《Journal of Coastal Conservation》2012,16(4):543-553
This paper describes an application of the Boussinesq-type COULWAVE model to study the wave hydrodynamics in the vicinity of a multi-functional artificial reef (MFAR). This reef is under investigation and consists of a supplementary protection solution for the Leirosa sand dune system located at South of Figueira da Foz, on the Portuguese West coast. Such installation near the coastline is expected to contribute to enhance the surfing conditions in the area, protect the sand dune system in the surroundings of Leirosa beach, and increase its environmental value. Numerical calculations with the COULWAVE model were performed for four test cases, considering two reef geometries (differing in the reef angle) and two incident wave conditions (storm condition and a common wave condition). Comparisons between the results obtained, in terms of wave heights and breaking line positions allow us to assess the influence of the reef on the hydrodynamics near the beach and around the reef. Moreover, the reef performance was analysed in terms of surfability and coastal protection. The surfability parameters (breaker height, Iribarren number and peel angle) were calculated for each test case using the numerical wave heights, wave directions and wave breaking positions. Comparisons of parameters allow characterizing the most appropriate configuration of the reef to improve the surfing conditions in the study area. A methodology based on numerical free surface elevations and horizontal velocity components was developed to calculate wave directions, since this is not a direct output of the COULWAVE model. Concerning coastal protection, analyses of the mean currents around the reef were used together with observations of the velocity cells near the shoreline as an indication of the sediment transport. 相似文献
857.
Gity Mir Mohamad Sadeghi Ramin Shamsi Mahsa Sayaf 《Journal of Polymers and the Environment》2011,19(2):522-534
Chemical recycling of PET has been developed by various methods. Aminolysis is one of chemical recycling methods of PET has
been developed recently. The obtained product using aminolysis, Bis (2-hydroxy ethylene) terephthalamide (BHETA), has the
potential for further reactions to obtain useful products. There are few reports on usage of recycled BHETA from PET waste
to synthesis of polyurethanes. On the other hand, various biodegradable polyurethanes have been synthesized using polycaprolactone
diol. Therefore, caprolactone is a new potential in synthesis of biodegradable polyurethanes from PET waste. In this work,
novel biodegradable polyurethanes have been synthesized using BHETA. In this order, at first polyols with different molecular
weights have been synthesized through ring opening polymerization of caprolactone by BHETA, then urethane linkages were formed
using HDI (Hexamethylene Diisocyanate) without chain extender. Chemical, thermal, mechanical and dynamic mechanical properties,
biodegradability, morphology and UV resistance of synthesized polyurethanes have been investigated. 相似文献
858.
Maria João Rocha Catarina Cruzeiro Mário Reis Eduardo Rocha Miguel Pardal 《Environmental monitoring and assessment》2013,185(10):8215-8226
In spite of its outstanding ecological and touristic importance the Ria Formosa Lagoon shows signs of anthropogenic pollution. Nonetheless, until the present survey no studies had ever documented the measurement of natural and pharmaceutical estrogens (17β-estradiol, estrone, and 17α-ethynylestradiol), xenoestrogenic industrial pollutants (4-octylphenol, 4-nonylphenol, and their mono and diethoxylates and bisphenol A), phytoestrogens (formononetin, biochanin A, daidzein, genistein), and sitosterol in this area. The 17 compounds measured herein are known as endocrine disrupters (EDCs) and act over the endocrine system even in few amounts (ng L?1–μg L?1). Thus to conclude about the influx of EDCs in the lagoon, water samples were taken every 2 months, during 1 year (2010), in low tide at nine sites distributed along the coastline. Water samples (1 L) were preconcentrated in the Oasis HLB cartridges and cleaned in silica cartridges before their analysis by GC-MS. Data showed the ubiquitous presence of potentially hazardous amounts of estrogens (particularly of ethynylestradiol, up to 24.3 ng L?1), nonylphenol (up to 547 ng L?1), and sitosterol (up to 12,300 ng L?1), mainly in summer, suggesting that the increase of the local number of inhabitants (tourists), the rise of the water temperature (up to 26 °C), and the blooming of local flora may interfere with the water quality parameters. This makes the lagoon a potential model to study. Taking into account the data, it was concluded that there are conditions for the occurrence of endocrine disruption in aquatic animals, even in areas included in the natural park of the Formosa. Besides, both the high amounts of un-ionized ammonia (up to 0.3 mg L?1) and phosphates (up to 1.6 mg L?1) my pose risks for local fauna and humans. 相似文献
859.
860.
Web-based GIS for collaborative planning and public participation: an application to the strategic planning of wind farm sites 总被引:2,自引:0,他引:2
Spatial planning typically involves multiple stakeholders. To any specific planning problem, stakeholders often bring different levels of knowledge about the components of the problem and make assumptions, reflecting their individual experiences, that yield conflicting views about desirable planning outcomes. Consequently, stakeholders need to learn about the likely outcomes that result from their stated preferences; this learning can be supported through enhanced access to information, increased public participation in spatial decision-making and support for distributed collaboration amongst planners, stakeholders and the public. This paper presents a conceptual system framework for web-based GIS that supports public participation in collaborative planning. The framework combines an information area, a Multi-Criteria Spatial Decision Support System (MC-SDSS) and an argumentation map to support distributed and asynchronous collaboration in spatial planning. After analysing the novel aspects of this framework, the paper describes its implementation, as a proof of concept, in a system for Web-based Participatory Wind Energy Planning (WePWEP). Details are provided on the specific implementation of each of WePWEP's four tiers, including technical and structural aspects. Throughout the paper, particular emphasis is placed on the need to support user learning throughout the planning process. 相似文献