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961.
The seascape nursery: a novel spatial approach to identify and manage nurseries for coastal marine fauna 下载免费PDF全文
Coastal marine and estuarine ecosystems are highly productive and serve a nursery function for important fisheries species. They also suffer some of the highest rates of degradation from human impacts of any ecosystems. Identifying and valuing nursery habitats is a critical part of their conservation, but current assessment practices typically take a static approach by considering habitats as individual and homogeneous entities. Here, we review current definitions of nursery habitat and propose a novel approach for assigning nursery areas for mobile fauna that incorporates critical ecological habitat linkages. We introduce the term ‘seascape nurseries’, which conceptualizes a nursery as a spatially explicit seascape consisting of multiple mosaics of habitat patches that are functionally connected. Hotspots of animal abundances/productivity identify the core area of a habitat mosaic, which is spatially constrained by the home ranges of its occupants. Migration pathways connecting such hotspots at larger spatial and temporal scales, through ontogenetic habitat shifts or inshore–offshore migrations, should be identified and incorporated. The proposed approach provides a realistic step forward in the identification and management of critical coastal areas, especially in situations where large habitat units or entire water bodies cannot be protected as a whole due to socio‐economic, practical or other considerations. 相似文献
962.
The International Plant Sentinel Network: a tool for Regional and National Plant Protection Organizations 下载免费PDF全文
Botanic gardens and arboreta are valuable but currently under‐utilized resources in plant health research. Within their vast collections of living plants, gardens play host to expatriate plant species from across the world. These plants offer unique opportunities to study damaging pest and pathogen threats before their introduction into a region where they would be considered invasive aliens. Through these studies, scientists can determine vital information related to these organisms, which can in turn be used to strengthen understanding, contribute to pest risk analysis activities and put in place appropriate quarantine measures or other management programmes. The International Plant Sentinel Network (IPSN) has been working for the last 3 years to provide the support and resources needed for gardens to contribute to such research. The next phase of the IPSN will be to coordinate this research; it will identify, facilitate and provide the already developed tools to contributing gardens. In this way, the IPSN will provide meaningful and valuable information to plant health experts which could help mitigate, or stop altogether, the damaging impacts of new and emerging invasive alien organisms. 相似文献
963.
The Red Queen in a potato field: integrated pest management versus chemical dependency in Colorado potato beetle control 下载免费PDF全文
Andrei Alyokhin David Mota‐Sanchez Mitchell Baker William E Snyder Sandra Menasha Mark Whalon Galen Dively Wassem F Moarsi 《Pest management science》2015,71(3):343-356
Originally designed to reconcile insecticide applications with biological control, the concept of integrated pest management (IPM) developed into the systems‐based judicious and coordinated use of multiple control techniques aimed at reducing pest damage to economically tolerable levels. Chemical control, with scheduled treatments, was the starting point for most management systems in the 1950s. Although chemical control is philosophically compatible with IPM practices as a whole, reduction in pesticide use has been historically one of the main goals of IPM practitioners. In the absence of IPM, excessive reliance on pesticides has led to repeated control failures due to the evolution of resistance by pest populations. This creates the need for constant replacement of failed chemicals with new compounds, known as the ‘insecticide treadmill’. In evolutionary biology, a similar phenomenon is known as the Red Queen principle – continuing change is needed for a population to persevere because its competitors undergo constant evolutionary adaptation. The Colorado potato beetle, Leptinotarsa decemlineata (Say), is an insect defoliator of potatoes that is notorious for its ability to develop insecticide resistance. In the present article, a review is given of four case studies from across the United States to demonstrate the importance of using IPM for sustainable management of a highly adaptable insect pest. Excessive reliance on often indiscriminate insecticide applications and inadequate use of alternative control methods, such as crop rotation, appear to expedite evolution of insecticide resistance in its populations. Resistance to IPM would involve synchronized adaptations to multiple unfavorable factors, requiring statistically unlikely genetic changes. Therefore, integrating different techniques is likely to reduce the need for constant replacement of failed chemicals with new ones. © 2014 Society of Chemical Industry 相似文献
964.
Rowan Trebilco Rosemary Gales Emma Lawrence Rachael Alderman Graham Robertson G. Barry Baker 《水产资源保护:海洋与淡水生态系统》2010,20(5):531-542
- 1. Seabirds killed incidentally in Australia's eastern tuna and billfish (ETBF) longline fishery between September 2001 and June 2006 were examined to evaluate species composition and to relate, where possible, capture events to operational and environmental factors.
- 2. During this period 2.129 million hooks on 2202 shots were observed, and 369 birds were reported killed. The majority (78%) of these were flesh‐footed shearwaters (Puffinus carniepes), 53% of which were male and 44% female. Smaller numbers of medium to large sized albatrosses (Diomedeidae, predominantly female) and other shearwaters (Puffinus spp.) and petrels (Pterodroma spp.) dominated the remainder of the bycatch.
- 3. Of the 369 birds reported taken as bycatch, 280 were available for necropsy, and species identifications performed in situ by observers were assessed. While observer identifications were generally correct for common species, performance was poor for less common ones.
- 4. The geographical location (latitude) of shots, season, time of day at which shots were set, and bait type and life status (dead or alive) influenced the seabird bycatch rate. The majority of captures (87% overall) occurred between 30 and 35°S, with bycatch being lowest in winter, and remaining at similar levels across the other seasons.
- 5. The use of live fish bait was generally associated with increased captures of both seabirds overall, and flesh‐footed shearwaters in particular. Copyright © 2010 John Wiley & Sons, Ltd.
965.
The rate and equilibrium constants for the pH-dependent hydration of a series of monoacylated anthocyanins semi-biosynthesized using a wild carrot suspension culture have been measured. The features of the acyl groups that decrease the hydration and thus decrease the loss of color of these anthocyanins are the presence of the side-chain double bond of the cinnamic acids and the presence of electron-donating substituents at the para-position of the acyl group. Methoxyl groups in the meta-position of the acyl groups have a greater effect than can be explained by their effects on the electron density in the acyl group. The data also suggest that there may be additional features of the acyl groups which contribute to the color retention in anthocyanins. 相似文献
966.
M Essmail D Baker J Collins S Vandewoude M Salman A A Hegazy 《Journal of veterinary diagnostic investigation》1999,11(3):237-239
A dot immunobinding assay (DIA) was used for the detection of antibody against bovine herpesvirus 4 (BHV-4) in experimentally infected specific-pathogen-free male and female rabbits. A semipurified virus preparation was used as the antigen, and protein A/G-horseradish-peroxidase conjugate and diaminobenzidine tetrahydrochloride were used as the detection system. Results of the DIA procedure on serum samples of experimentally infected male and female rabbits were compared with those of a complement-dependent virus neutralization (VN) test. None of the tested sera (0/60 samples) from either male or female rabbits were positive by the complement-dependent VN test. Results of the DIA procedure for the same tested sera were positive in 35 of 60 samples (58%) from BHV-4 infected rabbits, indicating higher sensitivity of DIA procedure as compared with the complement-dependent VN test. 相似文献
967.
P H Walz T G Bell B A Steficek L Kaiser R K Maes J C Baker 《Journal of veterinary diagnostic investigation》1999,11(6):505-514
Thrombocytopenia has been associated with type II bovine viral diarrhea virus (BVDV) infection in immunocompetent cattle, but the mechanism is unknown. The purpose of the present study was to develop and characterize a model of type II BVDV-induced thrombocytopenia. Colostrum-deprived Holstein calves were obtained immediately after birth, given a BVDV-negative and BVDV antibody-negative plasma transfusion, housed in an isolation facility, and randomly assigned to either control (n = 4) or infected (n = 5) groups. Infected calves were inoculated by intranasal instillation on day 3 of age with 10(7) TCID50 of the prototype type II isolate, BVDV 890, whereas control calves were sham inoculated. Blood counts and virus isolations from serum, white blood cells, and platelets were performed daily until day 12 after infection, at which time all experimental calves were euthanatized, and pathologic, virologic, and immunohistochemical examinations were performed. On physical examination, the control calves remained normal, but the infected calves developed pyrexia and diarrhea characteristic of type II BVDV infection. The platelet count decreased in all infected calves, and a statistically significant difference in the platelet count between control and infected calves was observed on days 7-12 after infection. In addition, the mean platelet volume and white blood cell counts also decreased. Examination of the bone marrow from the infected calves revealed immunohistochemical staining for BVDV antigen in megakaryocytes and evidence of concurrent megakaryocyte necrosis and hyperplasia. 相似文献
968.
D E Freeman J K Johnston G J Baker L L Hungerford T F Lock 《Equine veterinary journal》1999,31(3):208-211
This study was designed to evaluate the haemostatic suture as a means of preventing haemorrhage from the hysterotomy in mares after caesarean section. At 2 university hospitals 1982-1994, 48 mares had caesarean section for dystocia, 10 as an elective, and 8 mares concurrently with colic surgery. The haemostatic suture was used in 31 of 66 mares (47%) and surgery period was significantly (P<0.05) shorter when it was not applied. Anaemia (PCV<30%) was recorded in 13 (22%) of 58 mares, excluding the colic group, and the haemostatic suture did not after this proportion of mares that had anaemia. Anaemia was 5 times more probable following caesarean section than vaginal delivery, evidence that bleeding from the hysterotomy is a serious and common complication of caesarean section in mares. Severe uterine haemorrhage was recorded in 3 mares that had an haemostatic suture (10%) and in 2 mares that did not (6%). The latter two mares died of haemorrhage. The suture, therefore did not eliminate post operative anaemia and severe uterine haemorrhage. If omitted, the hysterotomy should be closed with a full thickness pattern that is sufficiently tight to compress vessels in the uterine wall. 相似文献
969.
C. Copeland E. Baker J. D. Koehn S. G. Morris I. G. Cowx 《Fisheries Management and Ecology》2017,24(1):82-92
This study profiled the motivations of recreational fishers involved in habitat management activities in Australia, USA, UK and Ireland. Fishers were surveyed using an online questionnaire. Primary motivations for involvement were social (‘putting something back’) rather than to increase fish numbers or improve fishing experience. Fishers were more likely to participate in habitat management if they were members of a club or organisation or self‐rated their knowledge of various aspects of fish ecology as very good. Most activities undertaken were relatively simple tasks such as picking up litter and contacting government or the media. Fishers that did not take part in habitat management cited lack of time as the principal reason, but organisational issues (lack of contacts, funding and ideas) were also important. There are considerable opportunities for government agencies and recreational fishing organisations to increase the participation of recreational fishers in habitat management as well as their involvement in more complex tasks through targeted programmes providing contact points, ecological information and administrative support. 相似文献
970.
Nitschke Craig R. Trouvé Raphael Lumsden Linda F. Bennett Lauren T. Fedrigo Melissa Robinson Andrew P. Baker Patrick J. 《Landscape Ecology》2020,35(7):1553-1570
Landscape Ecology - Effective conservation planning for species depends on vegetation models that can capture the dynamics of habitat elements across both spatial and temporal domains.... 相似文献