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  • 1. Maintaining ecological processes that underpin the functioning of marine ecosystems requires planning and management of marine resources at an appropriate spatial scale.
  • 2. The Great Barrier Reef World Heritage Area (GBR) is the world's largest World Heritage Area (approximately 348 000 km2) and second largest marine protected area. It is difficult to inform the planning and management of marine ecosystems at that scale because of the high cost associated with collecting data. To address this and to inform the management of coastal (approximately 15 m below mean sea level) habitats at the scale of the GBR, this study determined the presence and distribution of seagrass by generating a Geographic Information System (GIS)‐based habitat suitability model.
  • 3. A Bayesian belief network was used to quantify the relationship (dependencies) between seagrass and eight environmental drivers: relative wave exposure, bathymetry, spatial extent of flood plumes, season, substrate, region, tidal range and sea surface temperature. The analysis showed at the scale of the entire coastal GBR that the main drivers of seagrass presence were tidal range and relative wave exposure. Outputs of the model include probabilistic GIS‐surfaces of seagrass habitat suitability in two seasons and at a planning unit of cell size 2 km×2 km.
  • 4. The habitat suitability maps developed in this study extend along the entire GBR coast, and can inform the management of coastal seagrasses at an ecosystem scale. The predictive modelling approach addresses the problems associated with delineating habitats at the scale appropriate for the management of ecosystems and the cost of collecting field data. Copyright © 2010 John Wiley & Sons, Ltd.
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  • 1. Marine protected areas (MPAs) are today's cornerstone of many marine conservation strategies. Our 2015 study (Devillers et al., 2015) and others have shown, however, that the placement of MPAs is ‘residual’ to commercial uses and biased towards areas of lower economic value or interest.
  • 2. In this paper, we explored the impact of our study on marine science, policy and management practice.
  • 3. We reviewed the papers citing our work and compiled expert opinions on some of the impacts of our study.
  • 4. Results indicate a strong general uptake in the scientific community but more uneven impacts on policy and management in different contexts, with a likely smaller impact of the research on conservation practice.
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  • 1. Several species of marine mammals are at risk of extinction from being captured as bycatch in commercial fisheries. Various approaches have been developed and implemented to address this bycatch problem, including devices and gear changes, time and area closures and fisheries moratoria. Most of these solutions are difficult to implement effectively, especially for artisanal fisheries in developing countries and remote regions.
  • 2. Re‐zoning of the Great Barrier Reef World Heritage Area (GBRWHA) in 2004 closed 33% of the region to extractive activities, including commercial fishing. However, the impact of re‐zoning and the associated industry restructuring on a threatened marine mammal, the dugong (Dugong dugon), is difficult to quantify. Accurate information on dugong bycatch in commercial nets is unavailable because of the large geographic extent of the GBRWHA, the remoteness of the region adjacent to the Cape York Peninsula where most dugongs occur and the artisanal nature of the fishery.
  • 3. In the face of this uncertainty, a spatial risk‐assessment approach was used to evaluate the re‐zoning and associated industry restructuring for their ability to reduce the risk of dugong bycatch from commercial fisheries netting.
  • 4. The new zoning arrangements appreciably reduced the risk of dugong bycatch by reducing the total area where commercial netting is permitted. Netting is currently not permitted in 67% of dugong habitats of high conservation value, a 56% improvement over the former arrangements. Re‐zoning and industry restructuring also contributed to a 22% decline in the spatial extent of conducted netting.
  • 5. Spatial risk assessment approaches that evaluate the risk of mobile marine mammals from bycatch are applicable to other situations where there is limited information on the location and intensity of bycatch, including remote regions and developing countries where resources are limited.
Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
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  • 1. The threatened status of many sea turtle populations and their vulnerability to coastal development and predicted climate change emphasize the importance of understanding the role of environmental factors in their distribution and ecological processes. The factors driving the distribution of sea turtle nesting sites at a broad spatial scale is poorly understood.
  • 2. In light of the lack of understanding about physical factors that drive the distribution of turtle nesting, the relationship between nesting site distribution and the exposure of coastal areas to wind and wind‐generated waves was analysed. To achieve this, a Relative Exposure Index (REI) was developed for an extensive area in north‐eastern Australia and values of the index for nesting sites of five different sea turtle species and randomly selected non‐nesting sites were compared.
  • 3. Although there are differences between species, the results show that sea turtles nest in areas of higher REI values suggesting that wind exposure is related to the spatial distribution of sea turtle nesting sites, and it may also influence nest site selection in female turtles and/or the dispersal of hatchlings towards oceanic currents.
  • 4. The combination of these results with further research on other driving environmental factors, like oceanic currents, has the potential to allow for the identification and prediction of future nesting sites, for which conservation and management may become essential. Copyright © 2009 John Wiley & Sons, Ltd.
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Methyl iodide was evaluated as a soil fumigant as a potential replacement for the widely used soil fumigant methyl bromide. In container trials, methyl iodide was significantly more effective than methyl bromide against the plant parasitic nematodes Meloidogyne incognita, Heterodera schachtii and Tylenchulus semipenetrans and the plant pathogenic fungus Rhizoctonia solani. In small field plots, soil populations of root-knot nematodes were no longer detected after methyl iodide fumigation at an application rate of 112 kg ha-1. However, after growing a susceptible lima bean host for two months, substantial root-knot galling occurred, while Rhizobium nodulation was absent. At 168 kg ha-1 of methyl iodide, root-knot galling was reduced to less than 1%, and no Pythium propagules were recovered on selective detection media. These efficacy data support the conclusion that methyl iodide is a likely candidate for replacing methyl bromide as a soil fumigant. © 1998 SCI.  相似文献   
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Chilean needle grass [Nassella neesiana (Trin. & Rupr.) Barkworth; CNG] is a perennial spear grass that has invaded pastures in south‐eastern Australia and can lead to a substantial reduction of stockcarrying capacity during the summer months. This study examined a range of grazing, herbicide and pasture resowing options, alone or in combination, on CNG and introduced pasture grass basal cover, for several CNG‐infested sites in south‐eastern Australia. At each site, options were chosen on the basis that they were most likely to control the CNG infestation while maintaining a productive sheep‐grazing enterprise on grass pastures. After 2 years of management, the reduction in CNG basal cover in set stock plots that were sprayed with flupropanate, versus those not sprayed, ranged from non‐detectable to a reduction of 80%, depending on site location. After 5 years of management, the reduction ranged from zero to 50%. Grazing management or sowing of competitive pastures did not generally reduce CNG basal cover to low levels. None of the management options maintained reasonable levels of desirable perennial species by the end of 4–5 years. We conclude that, because of the persistence of CNG, the need for regular spraying of herbicide, and the relative ineffectiveness of other control methods, management systems may need to be developed that utilize CNG while minimizing its input to the soil seedbank.  相似文献   
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