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91.
水环境数学模型与GIS的集成研究   总被引:2,自引:0,他引:2  
从地理信息系统(GIS)的功能特点、环境信息的特性和水环境数学模型软件应用时存在不足的3个方面分析了GIS和水环境数学模型软件集成的必要性.介绍了GIS和水环境数学模型的集成方式以及苏州河三期综合整治决策支持系统的主要功能结构,重点从GIS和水环境数学模型集成方面介绍了地图矢量化、模型计算结果转化为相应数据库文件、数据库文件和GIS实现绑定以及断面水位动态演示的实现方法和重要作用.  相似文献   
92.
鲢鱼放养控制北京城市河湖水华试验研究   总被引:2,自引:1,他引:1  
介绍了利用鲢鱼控制北京城市河湖水华的试验研究,通过不同放养密度(0、17、51和103 g/m3)的现场围隔试验,对鲢鱼放养对水体水质和浮游生物的影响进行了分析.研究结果表明,鲢鱼放养使有鱼围隔中浮游生物量极低,从而使浮游植物基本不受浮游动物影响,而直接受鱼类影响;同时,中等密度(51 g/m3)的鲢鱼放养使水华蓝藻和微小藻的生长均得到了有效抑制,使藻类生物量最低.  相似文献   
93.
采用单级A/O程序复合膜生物反应器(HSMBR)处理高氨氮废水,研究在低DO浓度下系统对有机物、氨氮和总氮的去除效率。研究结果表明:在低DO浓度下,CODCr、氨氮的平均去除率分别为94.4%和92.8%。由于进水CODCr/TN值仅为2.01,则使得总氮平均去除率仅为69.4%,但是当系统亚硝化累积率从60.5%~67.1%提高到83.5%~86.4%时,系统总氮去除率提高了17.7%。另外,维持低DO浓度可以实现亚硝酸型同时硝化反硝化反应。  相似文献   
94.
This paper introduces an integrated water management model at the industrial park level. It suggests four approaches to water management: first, direct water reuse among users; second, water reuse among users by blending with freshwater; third, water reuse between users and a wastewater treatment plant; and fourth, groundwater recharge by reclaimed wastewater or other feasible applications in order to optimize the overall water efficiency. The model results in a comprehensive management methodology for optimizing water resources within an industrial park, seeking potential water reuse among industries, and incorporating the size and cost of reclaimed wastewater delivery systems. A case study is employed to test the model’s feasibility. An economic analysis of the optimized water use network is also carried out, showing the potential water and cost savings.  相似文献   
95.
Animal welfare involves societal and human values, ethical concerns and moral considerations since it incorporates the belief of what is right or what is wrong in animal treatment and care. This paper aims to ascertain whether the different dimensions of individual attitudes toward animal welfare in food choices may be characterized by general human values, as identified by Schwartz. For this purpose, an EU-wide survey was carried out, covering almost 2500 nationally representative individuals from five European countries. Compared with the previous literature this study shows a twofold novelty: (1) it develops a general framework to link individual enduring beliefs and attitudes toward animal welfare attributes in food choices; (2) the framework is analyzed within a broad-based cross-country study. Our empirical results prove that human values related to self-transcendence are strongly associated to overall animal welfare attitudes and especially to those explicitly related to food choices, while values related to the spheres of self-enhancement and conservatism are significantly associated to less sensitive attitudes to animal welfare. Moreover, our results appear to indicate that a determinant of animal welfarism in food choices is potentially associated to individual concerns regarding food safety issues.  相似文献   
96.
Changes in social framework conditions, accelerated by globalization or political inventions, have created new societal demands and requirements on companies. The concept of corporate social responsibility (CSR) is often considered a potential tool for meeting societal demands and criticism as a company voluntarily takes responsibility for society. The spotlight of public attention has only recently come to focus on agribusiness-related aspects of CSR. It is therefore the objective of this paper to provide an overview and a critical examination of the current state of research into CSR in agribusiness from different perspectives. Upon that this paper goals to define CSR special cases in agribusiness and derive implications for further research. CSR in agribusiness is a multi-dimensional and complex concept, which is sensitive to ongoing exchange processes between companies and stakeholders. We conclude with the special position of CSR in agribusiness and that future research should focus on adding value to industry-specific CSR aspects in the general CSR framework borrowed from management literature. Explorative fieldwork such as expert interviews with different stakeholders might be suitable for gaining insights into agribusiness-specific aspects of CSR in firms.  相似文献   
97.
Many think doing animal ethics demands we see moral humanism as a speciesist prejudice of the kind found with sexism and racism. The only serious case for this rests on the Argument from Marginal Cases. We find that argument to the point, but show that properly understood it supports humanism. Understanding why it does this lets us see how we ought to go on in animal ethics.  相似文献   
98.
A number of high-profile mislabeling incidents have led to many studies exploring the decision-making processes that firms make around performing illegal acts. However, it remains unclear why the proportion of firms conducting these acts constantly fluctuates and never disappears. Therefore, this study investigated this by carrying out a longitudinal analysis of food labeling in the Taiwanese rice industry. Drawing on the institutional isomorphism theory, it was found that the degree of mislabeling is negatively correlated with both the level of control of inspection regulations and public attention toward food regulations, and positively correlated with the previous proportion of firms mislabeling their products. Thus, there is a feedback loop between regulatory control, public attention, and the amount of mislabeling, with the amount of mislabeling not only being affected by the former degree of regulatory control, public attention, and mislabeling, but also modifying the future status of each of these. These findings further our understanding of the causal effects of illegal actions in the institutional agricultural environment.  相似文献   
99.
100.
The response of phytoplankton assemblages to the closure of urban sewage outfalls (USOs) was examined for the Mar Piccolo of Taranto (Mediterranean Sea), a productive semi-enclosed coastal marine ecosystem devoted to shellfish farming. Phytoplankton dynamics were investigated in relation to environmental variables, with a particular emphasis on harmful algal blooms (HABs). Recent analyses evidenced a general reduction of the inorganic nutrient loads, except for nitrates and silicates. Also phytoplankton biomass (chlorophyll a) and abundances were characterized by a decrease of the values, except for the inner area of the basin (second inlet). The phytoplankton composition changed, with nano-sized species, indicators of oligotrophic conditions, becoming dominant over micro-sized species. If the closure of the USOs affected phytoplankton dynamics, however, it did not preserve the Mar Piccolo from HABs and anoxia crises. About 25 harmful species have been detected throughout the years, such as the potentially domoic acid producers Pseudo-nitzschia cf. galaxiae and P seudo-nitzschia cf. multistriata, identified for the first time in these waters. The presence of HABs represents a threat for human health and aquaculture. Urgent initiatives are needed to improve the communication with authorities responsible for environmental protection, economic development, and public health for a sustainable mussel culture in the Mar Piccolo.  相似文献   
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