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101.
K M Brooks 《Journal of fish diseases》2009,32(1):59-73
In the development of integrated pest management (IPM) plans for the control of sea lice there are some components that are common to many areas. However, effective plans must be tailored to regionally varying environmental and biological factors affecting the severity of sea lice infections. This paper describes factors that would be involved in the development of an IPM plan for sea lice in the Broughton Archipelago, British Columbia. Temperature, salinity and currents affect the production, dispersion and competence of larvae of sea lice, Lepeophtheirus salmonis (Krøyer), as they develop to the infective copepodid stage. This information can be coupled with oceanographic conditions in the Broughton Archipelago and emerging computer models to define zones of infection where infections of new hosts are most likely. Salinity and temperature depend, in part, on river discharge in estuarine systems. River discharge depends on precipitation, snow pack and ambient temperatures, which can be monitored to help forecast the intensity of sea lice infections associated with both farmed and wild hosts. One of the goals of IPM planning is to reduce reliance on pesticides to avoid development of resistance in targeted parasites and to minimize environmental residues. Recommendations for developing an IPM plan specific to the Broughton Archipelago are provided along with a discussion of the additional information needed to refine IPM plans in this and other areas. 相似文献
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《Land Degradation u0026amp; Development》2018,29(6):1845-1857
To meet multiple environmental objectives, integrated programming is becoming increasingly important for the Global Environmental Facility, the financial mechanism of the Multilateral Environmental Agreements, including the UN Convention to Combat Desertification. However, integration is often not well defined. We therefore focus on identifying key aspects of integration and assessing their implementation in natural resources management projects. To that end, we draw on systems thinking literature and carry out an analysis of a random sample of Global Environmental Facility integrated projects and in‐depth case studies demonstrating lessons learned and good practice. We highlight the need for projects to identify clearer system boundaries and main feedback mechanisms within those boundaries, in order to effectively address drivers of environmental change. We propose a theory of change for integrated natural resources management projects, where short‐term environmental and socioeconomic benefits will first accrue at the local level. Implementation of improved integrated natural resources management technologies and practices at the local level can then be extended through spatial planning and strengthening of innovation systems. Financing and incentive mechanisms at the watershed and/or landscape/seascape level coupled with supporting policies could sustain and enhance ecosystem services at even larger scales and longer time spans. The evolving scientific understanding of factors influencing social, technical, and institutional innovations and transitions towards sustainable management of natural resources should be harnessed and integrated into influencing models and theory of change for complex social‐environmental problems, such as land degradation, and be coupled with up‐to‐date approaches for learning, adaptive management, and scaling up. 相似文献
105.
《Land Degradation u0026amp; Development》2018,29(8):2694-2706
Restoring degraded soils to support food production is a major challenge for West African smallholders who have developed local innovations to counter further degradation. The objective of this study was to evaluate a local farmer's technique that uses ramial wood (RW) as soil amendment (Piliostigma reticulatum shrub). Three treatments were applied in an experimental plot in Burkina Faso: control (no amendment), low RW (3 Mg fresh mass·ha−1·yr−1), and high RW (12 Mg fresh mass·ha−1·yr−1). RW was chipped to <5‐cm pieces and either buried or mulched. Topsoil carbon (C), nitrogen (N), and phosphorus (P) in control and low‐RW treatments declined after 7 years of continuous sorghum cultivation. Use of high‐RW amendment stabilized soil C content while N and P declined, thus not replenishing nutrient exports. Net contribution to soil C in the layer measuring 0–15 cm was 15% of the applied C in the high‐RW amendments. Although biomass and grain yields were higher in high‐RW treatments, crop productivity declined throughout the experiment for all treatments. Termite casts on RW treatments evidenced the potential role of wood‐foraging termites in diluting the impact of RW on soil fertility build‐up and soil water content. We conclude that mitigating soil degradation under semiarid conditions in Burkina Faso would require large amounts of woody amendments, particularly if the level of termite activity is high. Additional nutrient sources would be needed to compensate for removal in exported products so that biomass and grain production can be stabilized or increased. 相似文献
106.
教学与科研结合 提高本科教学质量 总被引：1，自引：0，他引：1
林向阳 《农产品加工．学刊》2009,(12):89-92
教学改革一直是全国高校教育改革的重中之重。近几年,福州大学在教学体制改革,尤其是如何利用自身有利条件,推行教学与科研结合的"导师制"、"3+1"教学人才培养模式、学生参加SRPT项目和各种专业竞赛等教学模式上,取得了良好效果。以生物科学与工程学院为例,总结探讨了该项改革方案的一些收获和建议。 相似文献
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栾嘉 《四川畜牧兽医学院学报》2008,(2):194-196
高素质的青年编辑人才是科技期刊发展的关键力量,其中创新素质起着举足轻重的作用。青年编辑在成长过程中,应该以正确理解科技期刊中的创新性和科技期刊编辑的刨新素质为前提,不断提高人文修养、注重知识的广度和深度、加强自身专业修养、加强主观能动性,从而达到提高创新素质的目的。 相似文献
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本研究针对某医药企业营销系统通用功能、基于角色的用户管理、数据的快速录入机制、基于图表的综合查询等功能的实现过程进行阐述,以供其他开发者参考。 相似文献