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161.
Integrative research on environmental and landscape change: PhD students' motivations and challenges
The growing demand for integrative (interdisciplinary or transdisciplinary) approaches in the field of environmental and landscape change has increased the number of PhD students working in this area. Yet, the motivations to join integrative projects and the challenges for PhD students have so far not been investigated. The aims of this paper were to identify the understanding of PhD students with regard to integrative research, their motivations to join integrative projects, their expectations in terms of integration and results, and to reveal the challenges they face in integrative projects. We collected data by a questionnaire survey of 104 PhD students attending five PhD Master Classes held from 2003 to 2006. We used manual content analysis to analyse the free-text answers. The results revealed that students lack a differentiated understanding of integrative approaches. The main motivations to join integrative projects were the dissertation subject, the practical relevance of the project, the intellectual stimulation of working with different disciplines, and the belief that integrative research is more innovative. Expectations in terms of integration were high. Core challenges for integration included intellectual and external challenges such as lack of knowledge of other disciplines, knowledge transfer, reaching depth, supervision, lack of exchange with other students and time demands. To improve the situation for PhD students, we suggest improving knowledge on integrative approaches, balancing practical applicability with theoretical advancement, providing formal introductions to other fields of research, and enhancing institutional support for integrative PhD projects. 相似文献
162.
Jung-Chen Huang William J. Mitsch Andrew D. Ward 《Journal of the American Water Resources Association》2010,46(5):957-971
Huang, Jung-Chen, William J. Mitsch, and Andrew D. Ward, 2010. Design of Experimental Streams for Simulating Headwater Stream Restoration. Journal of the American Water Resources Association (JAWRA) 1-15. DOI: 10.1111/j.1752-1688.2010.00467.x Abstract: Headwater streams flowing through agricultural fields in the midwestern United States have been extensively modified to accommodate subsurface drainage systems, resulting in deepened, straightened, and widened streams. To restore these headwater streams, partial or total reconstruction of channels is frequently attempted. There are different approaches to reconstructing the channel, yet there is little evidence that indicates which promises more success and there has been no experimental work to evaluate these approaches. This study designs three experimental channels – two-stage, self-design, and straightened channels – on a human-created swale at the Olentangy River Wetland Research Park, Columbus, Ohio, for long-term evaluation of headwater stream evolution after restoration. The swale receives a continuous flow of pumped river water from upstream wetlands. Using streamflow and stage data for the past 12 years, a channel-forming discharge of 0.18 m3/s was estimated from bankfull discharge, effective discharge, and recurrence interval. These stream channels, after construction, will be monitored to evaluate physical, chemical, and biological responses to different channels over a decade-long experiment. We hypothesize that the three stream restoration designs will eventually evolve to a similar channel form but with different time periods for convergence. Monitoring the frequency and magnitude of changes over at least 10 years is needed to document the most stable restored channel form. 相似文献
163.
Nitrate in shallow groundwater in typical agricultural and forest ecosystems in China, 2004-2010 总被引:2,自引:0,他引:2
The nitrate-nitrogen(NO 3-N) concentrations from shallow groundwater wells situated in 29 of the Chinese Ecosystem Research Network field stations,representing typical agroand forest ecosystems,were assessed using monitoring data collected between 2004 and 2010.Results from this assessment permit a national scale assessment of nitrate concentrations in shallow groundwater,and allow linkages between nitrate concentrations in groundwater and broad land use categories to be made.Results indicated that most of the NO 3--N concentrations in groundwater from the agroand forest ecosystems were below the Class 3 drinking water standard stated in the Chinese National Standard:Quality Standard for Ground Water(≤ 20 mg/L).Over the study period,the average NO 3--N concentrations were significantly higher in agro-ecosystems(4.1 ± 0.33 mg/L) than in forest ecosystems(0.5 ± 0.04 mg/L).NO 3-N concentrations were relatively higher(> 10 mg N /L) in 10 of the 43 wells sampled in the agricultural ecosystems.These elevated concentrations occurred mainly in the Ansai,Yucheng,Linze,Fukang,Akesu,and Cele field sites,which were located in arid and semiarid areas where irrigation rates are high.We suggest that improvements in N fertilizer application and irrigation management practices in the arid and semi-arid agricultural ecosystems of China are the key to managing groundwater nitrate concentrations. 相似文献
164.
生态文明建设要有坚实的公民环境教育作支撑。公民环境教育的文化价值是环境教育价值的内在表现形式之一。作为生态文明建设的重要组成部分,环境教育与生态文明建设有着不可断裂的天然的关系。生态文明建设需要环境教育的文化价值体现。环境教育的文化价值能够促进生态文化的生成与人文资源的开发,能够发挥环境教育的文化选择与批判功能,促进价值观念转型,能够发挥环境教育的文化传播功能,促进人文理性精神的活化。 相似文献
165.
微生物絮凝剂TH6的絮凝特性研究 总被引:10,自引:0,他引:10
从活性污泥中分离出一株絮凝活性较高的絮凝剂产生菌TH6,采用由其产生的絮凝剂对高岭土悬浊液和多种实际废水进行了絮凝净化实验,结果表明,TH6絮凝剂固液分离效果良好,CODCr去除率51.0%-71.5%,SS去除率88.5%-94.3%。 相似文献
166.
通过NID工艺在沈阳热电厂25MW机组烟气脱硫中的工程应用,研究了电除尘器收集高浓度粉尘时的特性原理及脱硫后的效果和效率等 相似文献
167.
通过研究黄河原状水样COD值与澄清水COD值的关系,得出黄河泥沙对分析结果影响太大,不能合理分析黄河水质受污染的程度,建议对黄河水质COD监测与评价采用原状水与澄清水同时进行的方案为最佳. 相似文献
168.
Richard G. V. Boelens 《Journal of Coastal Conservation》1996,2(2):169-174
The Irish Sea’s distinctive hydrographic features present unique opportunities for research into the complex processes that
regulate shelf-sea ecosystems. Such studies are essential in developing capabilities to detect and evaluate change in marine
environments. A 1993 review showed almost 230 projects underway on the Irish Sea, spanning all the major fields of marine
science. But a large proportion of research projects failed to indicate the purpose of the work; overall, there was a remarkable
absence of clarity and specificity in the objectives. Progress in some fields is also hampered by insufficient coordination
and cohesion; at present there are no standing arrangements between Ireland and the United Kingdom that provide for bilateral
co-ordination of scientific work in the area. There is clearly a need for a more planned and integrated Irish Sea science
programme to provide information for management purposes and also to advance scientific understanding of the components and
functions of Irish Sea ecosystems, and how and why they change with time. There is a common belief that the first of these
predominantly involves monitoring, and the second research. However, the paper cautions that this is a dubious and unnecessary
distinction. A strategy aimed at better integration of research and monitoring (e.g. a framework of linked objectives and
targets) could substantially increase the information dividend from current investments in Irish Sea science. Based on a joint
Irish/UK review, this paper outlines studies and approaches that are seen as key elements of a future, more relevant and cost-effective
research programme for the Irish Sea. 相似文献
169.
以贵溪冶炼厂几个主要阶段的环保投入、对周边环境的影响等为依据。结合可持续发展理论,探讨经济发展与环境保护的相互关系,寻求工业企业可持续发展的模式与对策,总结值得借鉴的经验。 相似文献
170.
论述了污水管理方案的主要内容和一般要求,以及必要的实验研究:技术路线、最佳工艺条件、治理效果曲线,提出了研制污水治理方案应注意的几个问题。 相似文献