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981.
Effect of salinity on the growth, biological activity and secondary metabolites of some marine fungi
HUANG Jingjing LU Chunhu QIAN Xiaoming HUANG Yaojian ZHENG Zhonghui SHEN Yuemao 《海洋学报(英文版)》2011,30(3):118-123
The study investigated the effects of salinity on growth,antimicrobial activities and secondary metabolites of 47 marine filamentous fungi isolated from the East China Sea near the western shore of the Taiwan Straits.The results indicate that NaCl promoted the growth up to 91.5% of test strains.However,only 14.9% of them showed a significant increase of antimicrobial activity against Candida albicans.When incubated in different concentrations of NaCl,the colony growth, antimicrobial activities and composition of secondary metabolites of the strain Ty01b-8 of Penicillium sp.varied.Treatment with KCl also showed a similar effect.An alkaloid isolated from the fermentation broth of Ty01b-8 was identified as chrysogine,inhibition activity of which against Hela cells was 15.05% at 20 μ g/ml,and yield was 4.4 and 4.9 times higher in 3 percent and 6 percent NaCl treatments,respectively, compared with the non-salt culture condition. These findings prove that salinity is an important factor influencing growth and secondary metabolites of some marine fungi,which can be used to screen for new metabolites from marine fungi,and to enhance their metabolites production in industrial fermentation. 相似文献
982.
Darcy L. Gray Rosaline R. Canessa C. Peter Keller Philip Dearden Rick B. Rollins 《Marine Policy》2011
Information about spatial patterns of recreational boating is important for managing environmental, safety, and social impacts. However, traditional spatial mapping techniques such as remote sensing are often unable to project entire vessel routes or to link with other important data such as demographics, activities, or purpose of trip. This study, conducted in a part of Canada’s southern Strait of Georgia, uses an on-the-water-questionnaire to map recreational boating distribution/density in a complex, multiple-use marine setting. Goals of this study were to explore an on-the-water questionnaire as a means of capturing boating distribution and density, explore the potential contributions of such information to marine spatial planning, and assess the strengths and limitations of the method. Boaters (n=519) were intercepted while engaged in boating trips and were asked to plot the route of their trip on a map of the region. Information was imported into ArcGIS for analysis and display of vessel distribution and density. The resultant spatial dataset has a number of applications for marine spatial planning and management. Strengths of this method include collection of entire vessel routes, linking spatial data to questionnaire variables, and a high response rate. Limitations include some bias towards sample sites and issues of respondent accuracy, as well as cost and effort. Recommendations for management and research are made. 相似文献
983.
Ashley McCrea-Strub Dirk Zeller Ussif Rashid Sumaila Jay Nelson Andrew Balmford Daniel Pauly 《Marine Policy》2011
While the recurrent cost of managing marine protected areas (MPAs) has been documented and estimated, there has been virtually no attempt to quantify the cost of establishing MPAs in the first place. This lack of attention is likely the result of the complexity of the process, involving often uncoordinated efforts of a multitude of governmental and non-governmental entities over a protracted period of time with no clear start and end-point. Using information gathered from a representative subset of MPAs worldwide, this paper presents the first attempt to identify and describe the various components, and explore potential predictors of the total funds spent in the course of establishment. The thirteen MPAs studied vary in size (from <1 to >360,000 km2), location (including near- and offshore in both developed and developing countries), objectives and degree of protection. Variation in MPA start-up costs is shown to be most significantly related to both MPA size and the duration of the establishment phase. Development of a method to estimate the potential cost of establishing proposed MPAs should play a crucial role in the conservation planning process. 相似文献
984.
Peter S. Ross Jay Barlow Thomas A. Jefferson Brendan E. Hickie Tatiana Lee Christina MacFarquhar E. Christien Parsons Kimberly N. Riehl Naomi A. Rose Elisabeth Slooten Chia-Yang Tsai John Y. Wang Andrew J. Wright Shih Chu Yang 《Marine Policy》2011
The adoption of endangered species laws in various nations has intensified efforts to better understand, and protect, at-risk species or populations, and their habitats. In many countries, delineating a portion of a species' habitat as particularly worthy of protection has become a mantra of these laws. Unfortunately, the laws themselves often provide scientists and managers with few, if any, guidelines for how to define such habitat. Conservationists and scientists may view protecting part of the habitat of an endangered species as an ineffectual compromise, while managers may be under pressure to allow a range of human activities within the species' habitat. In the case of small cetaceans, establishing boundaries for such areas can also be complicated by their mobility, the fluid nature of their environment, and the often ephemeral nature of their habitat features. The convergence of multiple human impacts in coastal waters around the world is impacting many small cetaceans (and other species) that rely on these areas for feeding, reproducing, and resting. The ten guiding principles presented here provide a means to characterize the habitat needs of small, at-risk cetaceans, and serve as a basis for the delineation of ‘priority habitat’ boundaries. This conceptual approach should facilitate a constructive discourse between scientists and managers engaged in efforts to recover endangered species. The degree to which the recovery of an at-risk species can be reconciled with sustainable economic activity will depend in part on how well these principles are incorporated into the delineation of priority habitat. 相似文献
985.
As climate change has driven dramatic changes in Northern sea ice regimes, marine mammals have gained iconic status around the world reflecting the perils of global warming. There is a tension between policies that have international support like a ban on seal hunting or whaling, and the adoption of adaptive, flexible rules that are likely to work in Northern places. Whereas most wildlife policy focuses on biological information to inform policy strategy, this analysis focuses on the “human dimensions” of Northern marine mammal management. This research examines ways in which human relationships and modes of governance affect conservation success. Standard analyses of risk to animal populations focused on direct sources of take are inadequate to address multi-causal, complex problems such as climate-induced habitat loss or increased industrialization of the Arctic Ocean. Early conservation policy strategies focusing on the moratorium of take have eliminated or reduced such practices as commercialized hunting and high levels of fisheries bycatch, but may be less relevant in an era in which habitats and climate changes are key drivers of population dynamics. This paper argues that effective adaptive policy requires new ways of learning about and governing human interactions with marine mammals. Through an exploration of marine mammal management in three Northern regions (Alaska, Nunavut, and the Finnish Baltic Sea coast), the paper analyzes the extent to which these marine mammal management regimes are practicing adaptive governance, that is, building cross-scale (local to international) understanding while allowing actors at the local scale the flexibility to direct the creation of rules that are ecologically robust and likely to succeed. Lessons are taken from these examples and used to propose selected policy and research recommendations for the marine mammal policy community. 相似文献
986.
Jérôme Spitz Yves CherelStéphane Bertin Jeremy KiszkaAlexandre Dewez Vincent Ridoux 《Deep Sea Research Part I: Oceanographic Research Papers》2011,58(3):273-282
Long-finned pilot whales (Globicephala melas), Risso's dolphins (Grampus griseus), melon-headed whales (Peponocephala electra), Cuvier's beaked whales (Ziphius cavirostris), Sowerby's beaked whales (Mesoplodon bidens), northern bottlenose whales (Hyperoodon ampullatus), sperm whales (Physeter macrocephalus), dwarf sperm whales (Kogia sima) and pygmy sperm whales (Kogia breviceps) make up the large community of deep-diving odontocetes occurring off the Bay of Biscay, northeast Atlantic. The ecology of these toothed cetaceans is poorly documented worldwide. The present study described their prey preferences from stomach content analysis and showed resource partitioning within the assemblage. The majority of the species appeared to be mostly teutophageous. Fish was an important food source only for the Sowerby's beaked whale and, to a lesser extent, for the long-finned pilot whale. In terms of foraging habitats inferred from prey composition, either pelagic oceanic or demersal neritic habitats were exploited by toothed whales in the Bay of Biscay, with only the long-finned pilot whale foraging in the two habitats. Finally, with more than 14,000 identified cephalopods from 39 species, the present study highlighted also the poorly known deep-sea cephalopod community off the Bay of Biscay using top predators as biological samplers. 相似文献
987.
海洋功能区划符合性判别方法初探——以港口功能区为例 总被引:2,自引:0,他引:2
借鉴国外用海兼容性和土地使用兼容性,分析了海洋功能区划符合性内涵,基奉原则,并以港口功能区为例,分析了港口用海对海洋环境的影响,建立了港口功能特征指标,以及港口功能区与海域使用之 间对照表.通过搭建起海域使用和海洋功能区划之间的桥梁,更好地为海域使用审批管理提供技术支持. 相似文献
988.
Arctic coastal populations share a close relationship with their environment consisting of linkages among communities, landscapes and seascapes, and the social institutions developed to sustain the system. This cultural–biogeophysical dynamic is termed throughout the section as a social–ecological system (SES). Marine mammals constitute a large portion of the subsistence diet for these communities, and as such represent key ecological services provided by the system. At the same time, marine mammals have gained iconic status as symbols for climate change in the North. A tension results between the demands of balancing on one hand good policy optics consistent with national and international norms and, on the other hand, flexible and adaptive institutions able to take on the task of managing resources in a dynamic, changing North. This tension and associated policy solutions such as co-management are explored in a series of papers focusing on marine mammal management dilemmas and policy practices around the circumpolar North. This introduction communicates the problem context and describes the five papers making up this special section. A guiding premise to this work is that new international pressures to implement moratoria on marine mammal hunting in the North ignore critical human dimensions of marine mammal management. Such policy proposals are unlikely to succeed in areas that require collaboration across scales. Simultaneously, new local-scale participation in multi-level management regimes holds promise for creating more resilient marine mammal SESs. 相似文献
989.
This paper examines the Quaternary changes in the coastal zone of northwestern Portugal through the relationship between sediments and landforms. By interpolating the available data from geomorphology, lithostratigraphy, sedimentology and geochronology, it was possible to reconstruct existing palaeoenvironments, the oldest of which date back to the last interglacial. The main landforms are a high and a low platform bounded by scarps. River sands and silty sediments formed in a lacustrine environment (Antas Formation, MIS 5) are associated with the high platform. Two deposits are associated with the low platform: the Cepães Formation (MIS 3) consisting of a lower set of river sand beds and an upper gravel beach bed, and the Aguçadoura Formation (MIS 1) consisting of Holocene lagoonal beds. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
990.
Ulrike Herzschuh Chengjun Zhang Steffen Mischke Rainer Herzschuh Farhid Mohammadi Birgit Mingram Harald Kürschner Frank Riedel 《Global and Planetary Change》2005,46(1-4):361
The history (45–0 ka BP) of the aquatic vegetation composition of the shallow alpine Lake Luanhaizi from the NE Tibetan Plateau is inferred from aquatic plant macrofossil frequencies and aquatic pollen and algae concentrations in the sediments. C/N (range: 0.3–100), δ13C (range: −28 to −15‰), and n-alkane measurements yielded further information on the quantitative composition of sedimentary organic matter. The inferred primary production of the former lake ecosystem has been examined in respect of the alternative stable state theory of shallow lakes [Scheffer, M., 1989. Alternative stable states in eutrophic, shallow freshwater systems: a minimal model. Hydrobiological Bulletin 23, 73–83]. Switches between clear and turbid water conditions are explained by a colder climate and forest decline in the catchment area of Lake Luanhaizi. The macrofossil-based reconstruction of past water depth and salinity ranges, as well as other organic matter (OM) proxies allowed climatic inferences of the summer monsoon intensity during the late Quaternary. Around 45 ka BP, conditions similar to or even moister than present-day climate occurred. The Lake Luanhaizi record is further evidence against an extensive glaciation of the Tibetan Plateau and its bordering mountain ranges during the Last Glacial Maximum. Highest lake levels and consequently a strong summer monsoon are recorded for the early Holocene period, while gradually decreasing lake levels are reconstructed for the middle and late Holocene. 相似文献