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Land use, rainfall and erosion risk on the South Downs 总被引：1，自引：0，他引：1
J. Boardman 《Soil Use and Management》1991,7(1):34-37
Abstract. In 1989–90 over 80% of the erosion on agricultural land in the South Downs was on ploughed or cultivated surfaces prepared for spring planting of cereals. This was in contrast to the pattern in previous years when most erosion was in winter cereal fields. An unusual late winter rainfall peak was the primary cause. Periods of erosion risk associated with other land uses on the South Downs are also discussed. 相似文献
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John Boardman 《Land Degradation \u0026amp; Development》2016,27(4):1307-1307
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Fabian H. Leendertz Georg Pauli Wayne Boardman Heinz Ellerbrok Sandra Junglen Boesch Christophe 《Biological conservation》2006,131(2):325-337
Until recently, the focus of great ape behavioural and ecological research has been distinct from the focus of scientists working in medical and veterinary sciences. More scientists are calling for a connection between medical and field research due to recent disease outbreaks in great apes, including Ebola, and indications of cross-transmission of Ebola and other viruses between primates and humans. A major limitation to progress is the lack of information on infectious diseases and their transmission in wild primates. Here, we present examples of successful pathogen detection in wild great apes and describe approaches and techniques that can be used in the field, focusing in particular on investigation of deaths and non-invasive sample collection. This interdisciplinary approach is providing new insights to infectious diseases of great apes and is helping to protect the health of great ape populations. This framework can also be applied to other mammals under threat from infectious diseases, including African wild dogs, seals and Tasmanian devils. In addition to providing benefits for great ape conservation, research that integrates infectious disease with primate ecology provides insights to emerging diseases in humans and the role of disease in primate evolution. 相似文献
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Robin K. King Stephen A. Smith Merle D. Pierson Gregory D. Boardman Charles W. Coale Jr. 《Journal Of Applied Aquaculture》2013,25(2):79-92
ABSTRACT Pathogenic microorganisms may be incorporated into biofilms found in aquaculture systems, causing recurring exposure to potential disease agents. Aerobic plate counts, the presence of Enterobacteriaceae, and the presence of Escherichia coli, modified to express a green fluorescent protein (GFP E. coli), was used to evaluate the effectiveness of various sanitizers in decreasing bacterial incorporation into newly generated biofilms in recirculating aquaculture systems. Disks of Buna-N rubber, polyvinyl chloride (PVC), chlorinated PVC, glass, fiberglass, and stainless steel were placed in aquariums stocked with Nile tilapia, Oreochromis niloticus. The effectiveness of water, an alkaline cleanser, sodium hypochlorite, a quaternary ammonium compound, or peracetic acid as a sanitizer was evaluated on each substrate by enumerating total plate counts, GFP E. coli, and Enterobacteriaceae. Sodium hypochlorite and peracetic acid were the most effective sanitizers, with an overall percentage reduction of GFP E. coli of approximately 2 logs10. The quaternary ammonium compound was moderately effective, 1 log10, against the target organisms. Water demonstrated a 2 log10 reduction of the total plate count, suggesting that some mechanical cleaning was achieved. The type of material used as substrate for the biofilm had no significant (P?>?0.05) effect on the effectiveness of the sanitizers. 相似文献
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Agricultural landscapes that are intensively farmed, as in western Europe, face the challenge of a transition to more sustainable systems. Although erosion rates are relatively low in western Europe, the agricultural landscape is confronted by the need to mitigate the off-site impacts of erosion. An important challenge is that of disrupting connectivity between runoff and sediment sources, often farmers' fields, and freshwater systems or local communities. Mitigation strategies should include monitoring of erosion rates and off-site impacts and a mix of engineered and alternative measures such as buffer strips and retention ponds. Also needed are supportive government policies and actions including awareness of institutional memory problems and the promotion of farmer education. For the future, the risk of climate change must be appreciated and built into the planning of comprehensive mitigation strategies. Our perspective is that the overall aim should be a ‘sustainable agricultural landscape’ and not simply a reduction of erosion and runoff on farmers' fields. 相似文献
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Abstract. High rates of erosion are reported from three sites on brickearth (loess) soils in east Kent. Problems are acute where soils are used for intensive production of vegetables and salad crops. Erosion appears to be the result of structural instability, lack of crop cover for much of the year, and certain managment practices, such as ridging the soil for the crop. In the autumn of 1984, about 120 tonnes of soil was lost from rills in a field of onions: an erosion rate of about 15 t ha−1 . A large field under winter cereals also eroded and this resulted in damage to property. Conservation techniques are recommended. 相似文献