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131.
Marian E. Vernon Zachary Bischoff-Mattson Susan G. Clark 《Human Dimensions of Wildlife》2016,21(1):65-85
Incidents of human–wildlife conflict can solidify participant perspectives and expectations, and reveal underlying social and institutional dynamics. We describe and analyze two incidents of conflict between hunters and grizzly bears in 2011 and 2012. Both incidents were associated with the controversial elk hunt in Grand Teton National Park, Wyoming. We gathered quotes from opinion-editorials and interviews, categorized quotes according to type, and used cluster analysis to identify discourses and associated coalitions of participants. We examined how participants defined problems, used evidence, and advocated solutions in relation to these incidents. Participant discourses addressed technical and procedural issues of regional wildlife management that extended beyond these incidents, revealing divergent expectations about wildlife management on public lands. Existing decision-making processes dominated by government agencies do not appear to be addressing these expectations. We recommend an integrative, outside appraisal of regional elk management to address conflict and support ecologically sound decision-making that serves common interests. 相似文献
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Henrice M. Jansen Sander Van Den Burg Bas Bolman Robbert G. Jak Pauline Kamermans Marnix Poelman Marian Stuiver 《Aquaculture International》2016,24(3):735-756
Following the Blue Growth ambition of the European Commission, the interest in the potential of offshore is growing. This paper aimed to contribute to the discussion on the feasibility of offshore aquaculture development and its potential for multi-use with other maritime activities. A review of national and international projects forms the basis of the paper, where the Dutch North Sea is used as a case-study area. Analysis of technical, economic and ecological boundaries indicated that the potential of fish culture is limited, that seaweed cultivation is likely to gain potential when challenges related to processing will be overcome and that mussel culture has the highest potential in the near future. The North Sea is an area where many stakeholders claim space, which might set boundaries to the number of sites available for mussel culture. Competing claims are a potential source of conflict but may also lead to mutual benefits when smart combinations are sought, e.g. with wind parks, fisheries and nature conservation; especially, the possibility of combining mussel culture in or around wind parks is worthwhile to be further explored. A spatial distribution model adapted for the Dutch North Sea conditions demonstrated that offshore mussel production in wind farms can be profitable. Yet, the commercial interest for offshore development of mussel culture is still limited. Actions required to stimulate further development of the offshore mussel industry are presented for the government, the private sector, research institutes and civil society organizations. 相似文献
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Maria Pia Argentieri Trifone D’Addabbo Aldo Tava Augusta Agostinelli Marian Jurzysta Pinarosa Avato 《European journal of plant pathology / European Foundation for Plant Pathology》2008,120(2):189-197
The nematicidal activity of saponins from Medicago arborea (tops), M. arabica (tops and roots) and M. sativa (tops and roots) against the plant-parasitic nematode Xiphinema index was investigated. Nematicidal activity of related prosapogenins and sapogenins on X. index is also described. Saponins from Medicago spp. at different concentrations were all nematicidal, those from M. arborea tops being the less effective. In general, saponins induced 100% mortality at 500 μg ml−1 between 8 and 48 h, while prosapogenins resulted in toxicity starting at 125 μg ml−1. Differences in the effects on X. index induced by prosapogenins and sapogenins were less pronounced, although prosapogenins displayed a larger range of activity.
Assays with purified sapogenins demonstrated the relationship of the observed nematicidal activity of M. sativa and M. arborea to the content of the main aglycones (medicagenic acid and hederagenin, respectively) in the saponin extracts. Hederagenin
displayed the highest bioactivity, giving 38% mortality after 1 h at 125 μg ml−1. 相似文献
139.
Vanhaereny M d'Errico F Stringer C James SL Todd JA Mienis HK 《Science (New York, N.Y.)》2006,312(5781):1785-1788
Perforated marine gastropod shells at the western Asian site of Skhul and the North African site of Oued Djebbana indicate the early use of beads by modern humans in these regions. The remoteness of these sites from the seashore and a comparison of the shells to natural shell assemblages indicate deliberate selection and transport by humans for symbolic use. Elemental and chemical analyses of sediment matrix adhered to one Nassarius gibbosulus from Skhul indicate that the shell bead comes from a layer containing 10 human fossils and dating to 100,000 to 135,000 years ago, about 25,000 years earlier than previous evidence for personal decoration by modern humans in South Africa. 相似文献
140.
M. Marian Ijzerman Charles Hagedorn R. B. Reneau Jr 《Water, air, and soil pollution》1992,63(1-2):201-210
Two antibiotic resistant Escherichia coli strains and two host-specific coliphage strains were evaluated in a shallow-placed low pressure distribution (LPD) system placed in a soil that was unsuitable for a conventional system because of shallow depth to a restrictive soil horizon. Four independent LPD subsystems were installed with loading rates of 4.5, 5.7, 9.0, (loading rates based on Virginia regulations), and 17.5 L d?1 m?2; narrow trench design). The evaluation was conducted under different moisture and temperature conditions (summer 1989, and the winter 1990) and focused on the fate and transport of the biological tracers below each subsystem. All subsystems performed equally well with respect to hydraulic performance and retention of the biological tracers. Results indicated that >99.9% of the bacterial and coliphage tracers were retained within the subsystems during the summer of 1989, and >99% were retained during the winter of 1990. 相似文献