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641.
A bioassay‐directed fractionation of cultures of the fungus, Verticillium chlamydosporium, demonstrated nematicidal activity, due mainly to phomalactone. Compared with aldicarb, the lethal activity against Meloidogyne incognita was less, but its activity in suppressing root invasion was similar. The extract also contained monorden. © 2000 Society of Chemical Industry  相似文献   
642.
  • 1. The Galapagos Marine Reserve provides refuge for numerous threatened marine species, including 16 mammals, birds, reptiles and fish currently recognized on the 2006 IUCN Red List of Threatened Species, plus an additional 25 endemic fish, mollusc, crustacean, echinoderm, coral and macroalgal species that comply with threatened species criteria because of declining extent of occurrence or highly‐localized ranges, and hence also qualify for inclusion on the Red List.
  • 2. Threatened marine species with restricted ranges are not randomly distributed across the archipelago but tend to co‐occur at a limited number of sites that are predominantly located in the west. Sites at which threatened species are known to persist, particularly those with a large proportion of the global population, are here identified as sites of global conservation significance — key biodiversity areas.
  • 3. The majority (27) of the 38 inshore key biodiversity areas identified are currently protected from fishing because they lie within the 17% of coastal waters that is zoned as ‘no‐take’ tourism or conservation zones. All key biodiversity areas should be protected from extractive exploitation if threatened species are to be safeguarded. This can be achieved, at the minimum, through a relatively minor amendment to the existing marine zoning scheme, whereby an additional 2% of the coastline is dedicated to conservation.
Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
643.
  • 1. Within the Moray Firth, north‐east Scotland, there is a history of conflict between seals and salmon fisheries. Under the UK's Conservation of Seals Act 1970 (CoSA) seals are shot to protect fisheries. In 1999 six rivers in the Moray Firth were designated as Special Areas of Conservation (SACs) for Atlantic salmon under the EU Habitats Directive, and in 2000 an SAC for harbour seals was designated in the Dornoch Firth.
  • 2. In the 1990s salmon stocks declined. Fisheries managers believed the decline was partly caused by seal predation and consequently increased shooting effort. In years 1993–2003 Moray Firth harbour seal numbers declined possibly due to shooting, posing a potential threat to the status of the Dornoch Firth SAC. Meanwhile wildlife tourism based on marine mammals has increased. The declines in salmon and harbour seals, and the implementation of the Habitats Directive forced a watershed in the approach of statutory authorities to managing seals, salmon and tourism.
  • 3. In years 2002–2005 local District Salmon Fishery Boards, the Scottish Executive, Scottish Natural Heritage and stakeholders negotiated a pilot Moray Firth Seal Management Plan to restore the favourable conservation status of seal and salmon SACs, and to reduce shooting of harbour seals and seal predation on salmon.
  • 4. Key facets of the plan are the management of the Moray Firth region under a CoSA Conservation Order; application of the Potential Biological Removal concept to identify a limit of seals to be killed; management areas where removal of seals is targeted to protect salmon, while avoiding seal pupping and tourism sites; a training and reporting system for marksmen; a research programme, and a framework allowing an annual review of the plan.
  • 5. The plan was introduced in April 2005. A maximum limit of 60 harbour and 70 grey seals was set. Forty‐six harbour and 33 grey seals were killed in 2005 while in 2006 these figures were 16 and 42 respectively. Although the numbers killed were below the maximum limits in both years the returns raised questions about the plan's ability to manage seal shooting at netting stations. The plan provides a useful adaptive co‐management framework for balancing seal and salmon conservation with the protection of fisheries and/or fish farms and tourism for application in the UK and internationally.
Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
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Rangelands worldwide have been subject to broadscale modification, such as widespread predator control, introduction of permanent livestock water and altered vegetation to improve grazing. In Australia, these landscape changes have resulted in kangaroos (i.e. large macropods) populations increasing over the past 200 years. Kangaroos are a key contributor to total grazing pressure and in conjunction with livestock and feral herbivores have been linked to land degradation. We used 22 years of aerial survey data to investigate whether the density of 3 macropod species in the southern rangelands of Western Australia was associated with: (i) land use, including type of livestock, total livestock, density of feral goats, type of land tenure, and kangaroo commercial harvest effort; (ii) predator management, including permitted dingo control effort, estimated dingo abundance, and presence of the State Barrier Fence (a dingo exclusion fence); and (iii) environmental variables: ruggedness, rainfall, fractional cover, and total standing dry matter. Red kangaroos (Osphranter rufus) were most abundant in flat, open vegetation, on pastoral land, where area permitted for dingo control was high, and numbers were positively associated with antecedent rainfall with a 12-month delay. Western grey kangaroos (Macropus fuliginosus) were most abundant on flat, agricultural land, but less abundant in areas with high permitted dingo control. Euros (Osphranter robustus) were most abundant in rugged pastoral land with open vegetation, where permitted dingo control was high. While environmental variables are key drivers of landscape productivity and kangaroo populations, anthropogenic factors such as land use and permitted dingo control are strongly associated with kangaroo abundance.  相似文献   
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