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311.
环境试验夹具管理数据库的设计   总被引:1,自引:1,他引:0       下载免费PDF全文
以环境试验夹具为对象,针对其使用中存在的问题引入信息化管理,给出了环境试验夹具使用管理的数据库设计方案。环境试验夹具的信息化管理将是一种提高工作效率、缩短试验准备周期的有益探索。  相似文献   
312.
中亚热带常绿阔叶林湿沉降过程中盐基离子变化特征   总被引:6,自引:1,他引:5  
安思危  孙涛  马明  王定勇 《环境科学》2015,36(12):4414-4419
基于野外实验和室内实验相结合的方法,于2012年9月至2013年8月对四面山常绿阔叶林大气降水、穿透水、地表枯透水、土壤渗滤液进行了持续一年的森林不同层次盐基离子季节动态变化特征的研究.结果表明,四面山大气降水全年pH平均值为4.90,最大值为5.14,大气降水明显偏酸性;土壤层和林冠层能使降雨的p H值有所升高,其中土壤层对p H值的调升幅度最大,其次为森林冠层;森林冠层只对Na~+有一定的截留作用,降雨能够淋溶森林冠层的Ca~(2+)、Mg~(2+)、K~+;研究结果也表明,枯枝落叶的降解是导致各盐基离子质量浓度在枯透水中增加的主要原因;枯透水下渗的过程淋溶了森林土壤中的Ca~(2+)、Mg~(2+)、Na~+.四面山大气降水经过森林生态系统后Ca~(~(2+))、Mg~(2+)、Na~+、K~+的总截留率分别为33.82%、-7.06%、74.36%、42.87%,森林生态系统对Ca~(2+)、Na~+、K~+表现出了截留作用,其中对Na~+截留率最大.  相似文献   
313.
查阅相关资料,对鹤壁市淇河饮用水水源地基础环境展开调查,在淇河断面水质分析的基础上提出水源地保护对策和建议。  相似文献   
314.
文章较为详实地梳理了哈尔滨农村地区环境教育基地建设存在的问题,对问题产生的多种因素进行了深入地分析.目前农村环境教育基地建设规模有限,主要体现在基地建设的数量和规模上.基地建设的综合实践性不强,表现在内容单调、形式单一、缺乏互动性.科技成果含金量不高,转化难度较大,没有形成经济效益.资金短缺、基地建设的设计者的环境意识局限、专业人才队伍建设的落后和基地的管理机制缺失等因素是问题产生不可回避的理由.  相似文献   
315.
In the context of complex and unprecedented issues of global change, calls for new modes of knowledge production that are better equipped to address urgent challenges of global sustainability are increasingly frequent. This paper presents a case study of the new major research programme “Future Earth”, which aims to bring ‘research for global sustainability’ to the mainstream of global change research. A core principle of Future Earth is the co-production of knowledge with extra-scientific actors. In studying how the principle of co-production becomes institutionalised in the emerging structure of Future Earth, this paper points to the existence of three distinct rationales (logics) on the purpose and practice of co-production. Co-production is understood as a way to enhance scientific accountability to society (‘logic of accountability’), to ensure the implementation of scientific knowledge in society (‘logic of impact’), and to include the knowledge, perspectives and experiences of extra-scientific actors in scientific knowledge production (‘logic of humility’). This heterogeneous conception of knowledge co-production provides helpful ambiguity allowing actors with different perspectives on science and its role in society to engage in Future Earth. However, in the process of designing an institutional structure for Future Earth tensions between the different logics of co-production become apparent. This research shows how logics of accountability and impact are prominent in shaping the development of Future Earth. The paper concludes by pointing to an essential tension between being inclusive and transformative when it comes to institutionalising new modes of knowledge production in large research programmes.  相似文献   
316.
为了认识蔬菜产地土壤重金属富集现状,探索其解决途径,为污染防治措施提供科学依据,促进无公害蔬菜生产,确保蔬菜质量安全。在乌鲁木齐北郊蔬菜地采集26个土壤样品和7个水体样品,分别测定样品中Hg、As、Cr、Cd、Pb和Zn 6种重金属的含量。采用地积累指数(Igeo)、污染负荷指数(PLI)、潜在生态风险评价(RI)对蔬菜地土壤重金属污染及潜在生态风险进行分析。通过土壤与水样的结合,采用主成分分析法进行污染来源分析,结果表明:(1)乌鲁木齐安宁渠蔬菜基地土壤中Hg、Cr和Zn重金属含量的均值分别为新疆土壤背景值的5.74、1.74、1.52倍,其中Cd含量的均值是国家二级标准的2.69倍。地下水中Cr含量均值超过国家灌溉水限制标准,是其8.89倍。(2)6种重金属Igeo的平均值依次为Cd > Hg > Cr > Zn > As > Pb,其中Cd属于中-强度污染,Hg为中度污染,Cr为轻度污染,Zn、As和Pb均为清洁水平。研究区土壤区域污染负荷指数PLIzone为1.91,属于中度污染,其中Cd的贡献率最大,为56%,其次是Hg,贡献率为22%。土壤RI均值为673.1,属于严重潜在生态风险态势。(3)研究区土壤Pb、Cr和Zn,主要来自交通和农业活动等人为污染,As、Cd主要受自然母质和大气沉降的影响。该蔬菜基地潜在生态风险主要来自Cd和Hg,建议在农业生产中防范Cd、Hg的污染。  相似文献   
317.
This article applies a ‘knowledge brokering’ approach to contextualise the development of an integrated computer modelling tool into the real world policy context of adaptation of agriculture to climate change at the EU level. In particular, the article tests a number of knowledge brokering strategies described and theorised in the literature, but seldom empirically tested. The article finds that while the policy context can be used to identify a theoretically informed knowledge brokering strategy, in practice a strategy's ‘success’ is more informed by practical considerations, such as whether the tool development process is knowledge or demand driven. In addition, in practice the knowledge brokering process is found to be dynamic and messy, which is not always apparent in the literature. The article goes on to question the perception that there is always a need (or a desire) to bridge the gap between researchers and policy makers in the tool development process. Rather than a problem of design and communication, the science policy interface may be characterised more by a high level of competition between researchers and research organisations to have their tool legitimised by its use in the policy making process.  相似文献   
318.
Transdisciplinary approaches are becoming increasingly adopted as a way to research complex socio-environmental problems. Conceptually, transdisciplinarity aims to foster meaningful knowledge co-production through integrative and participatory processes that bring together diverse actors, disciplines, and knowledge bases. In practice, transdisciplinarity is more ambiguous. While there is a growing body of literature on such approaches, there remains no widely-accepted definition, concrete framework, or empirical strategy for how to carry out a transdisciplinary project. We propose that this lack of explicit structure and entrenched meaning leaves space for transdisciplinary approaches to be shaped by the evolving network of participating scientists and stakeholders, according to their perspectives of the approach and what it embodies. Here, we examine the perspectives of a diverse group of actors (n = 42) embarking on a 10-year transdisciplinary research project focused on building resilience to natural hazards and disasters in New Zealand. We present the findings of qualitative surveys and group interviews that investigate stakeholders’ and scientists’ early perspectives of transdisciplinary, or co-created, research. The study represents the first stage of longitudinal research that will continue over the course of the project. Results show that early actors in the project share an overall consistent understanding of co-created research. Participants described a process that integrated diverse people and knowledge; created benefits on both a social and personal level; fostered clear, two-way dialogue; and overcame pragmatic and intrinsic challenges. Collectively, participants agreed with adopting transdisciplinary approaches to natural hazard, risk, and resilience research, with stakeholders showing a stronger degree of agreement than scientists. While attitudes towards transdisciplinarity were overall positive, a number of underlying conflicts emerged in regards to carrying out new modes of knowledge production within traditional social and institutional structures. These conflicts result in a tension that is felt by actors involved in transdisciplinary projects early on, and in some cases, influences perception of their ability to fully participate in such an approach. Evaluating actor perspectives and expectations early in the transdisciplinary process can give insight into how attitudes, expectations, and conflicts might shape transdisciplinary efforts, and can provide relevant parameters for assessing change over time.  相似文献   
319.
高职教育实训基地建设的研究与实践   总被引:10,自引:0,他引:10  
实训基地建设是实现高职教育培养目标的需要,是培养高职人才的必要场所.本文对高职教育实训基地建设的意义、原则和实现功能等方面进行了探讨,并结合专业建设进行了有益的尝试.  相似文献   
320.
Soil acidity parameters (pH, basesaturation, exchangeable Al) in the organic and mineralsoil layers and in soil water (pH, dissolved organiccarbon, total Al, Al3+ and molar Ca/Al ratios) insix Norway spruce stands in different parts of Finlandwere compared. An attempt was also made to relate thedegree of defoliation in the tree stand to N and Sdeposition and soil parameters. No relationship was foundbetween soil acidity parameters and defoliation in thesix stands. Defoliation was positively correlated withstand age and the C/N ratio of the organic layer, andnegatively with the cation exchange capacity. The plotlocated on a so-called sulphate soil on the west coast ofFinland had very low soil pH values, and extremely highAl and SO4 2- concentrations and molar Ca/Alratios of well below 1.0 in soil water. Despite the highnatural acidity in the soil on this plot, defoliation inthe spruce stand was the lowest (mean 8.6%) of all sixplots. The results of this study indicate that soilacidity is not a major factor affecting stand conditionin these spruce stands, and that the variation in soilacidity parameters is closely related to climatic factorsand natural soil formation processes.  相似文献   
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