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A long-term rangeland monitoring programme needs to employ a field survey technique that is practicable, precise, powerful enough to distinguish change, not prone to worker bias, and able to distinguish real change from operator error arising from staff turnover. These criteria were used to evaluate a widely used grassland sampling technique in South Africa – the nearest-plant (with 200 points) method (NP) – against common alternatives, namely NP excluding forbs (NP-nf), the plant number scale (PNS; a cover-abundance method) and quadrat frequency (QF), using multivariate ordination and permutation tests. Four trained teams surveyed four grasslands using each method. PNS took more than twice as long as the other techniques, which were similarly rapid. Estimates of composition using NP methods were the most precise and PNS was least repeatable, with QF intermediate. Compositional differences between sites were most finely distinguished using NP-nf, followed by NP and QF. PNS was able to detect only marked differences and had the greatest potential for surveyor bias. The NP method, with or without including forbs, is therefore recommended for monitoring the species composition of mesic, dense grassland. Some suggestions for monitoring agencies on how best to use multivariate methods are presented. 相似文献
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Continuing professional development (CPD) is widely recognized as an important element in effective lifelong learning for veterinary surgeons. Traditional methods of CPD do not suit all learners, as issues such as location, time, cost, and structure sometimes prevent individuals from completing the required number of CPD study hours per year. The rapid development of the Internet, and with it the increasing scope and sophistication of e-learning, provides new opportunities to address some of these constraints on the provision of CPD. This article describes one way in which e-learning has been deployed effectively to support veterinary surgeons in practice. Since 2003, a series of six-week e-CPD courses has been offered by the Royal Veterinary College (RVC) in an online format, with no face-to-face teaching component. Participants enrolled in courses from May 2006 to January 2007 were found to come from 23 different countries. Analysis of feedback forms indicates a general satisfaction with this new way of studying, with a significant majority of participants stating that they would wish to use this approach again in future. The feedback indicates that e-learning can offer an effective alternative to traditional face-to-face courses and that its popularity is likely to grow in future as veterinarians become increasing familiar with and confident about working online. 相似文献
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Anesthesia for cardiac surgery in calves 总被引:2,自引:0,他引:2
C E Short A S Keats D Liotta C W Hall 《American journal of veterinary research》1968,29(12):2287-2294
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This article analyzes the relationship between forest resources, refugees, and the host population. The findings of the research
suggest that the host population are heavily dependent on the local forest for their daily needs such as fuelwood, timber,
grazing area, fodder for domestic animals, foods, and medicine in addition to cultural and esthetic needs. The forest has
also been relied upon for agricultural needs such as manufacture of agricultural tools, maintenance of irrigation water systems,
erosion control, and fertilizer needs. The forest was under a sustained demand as any other Terai forest of Nepal. After the
arrival of refugees in 1992, the demand for forest resources increased substantially. Initially, the construction of the refugee
camps decreased the total forest area and also required some felling of trees. More significantly, the refugees themselves
became active users of the forest resource, which generated extra pressure on the forest and created scarcity of forest resources.
Before the arrival of the refugees, forest management and monitoring of illegal use of the forest resources were carried out
by the government through its local forester office. The local residents were active users of the forest resources, but were
passive in managing and maintaining the forest resource. However, competition from the refugees instilled a desire in the
local population to safeguard and protect the dwindling resource against the external threat by creating the Humse Dumse Community
Forest. 相似文献