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731.
The effect of olive mill wastewater on seed germination after various pretreatment techniques 总被引:3,自引:0,他引:3
Olive mill wastewater (OMW) management has been a major issue of environmental concern for olive oil producing countries. OMW can be a serious nuisance, when disposed of untreated, due to its significantly high organic load, its phytotoxic properties and its relatively low biodegradability. Field and plant irrigation with raw or pretreated OMW is an easy and relatively inexpensive method to treat and dispose of OMW. Typical pretreatment techniques could be comprised of phase separation through a settling basin, dilution with water, aeration to promote biological degradation and pH neutralization. A full factorial experimental design approach was used here to study the main effects and interactions of the above four pretreatment techniques on the germination of tomato and chicory seeds. Results of the study showed that the most statistically significant technique affecting OMW phytotoxicity is water dilution. The next most significant technique was aeration. In particular, phytotoxicity decreased with increased OMW dilution with water, when OMW was aerated and without pH adjustment. pH neutralization resulted in increased phytotoxicity. Settling did not significantly decrease the phytotoxicity of settled OMW and is therefore not considered necessary in an OMW management system in which plant irrigation is the goal. The interaction of aeration and pH was, marginally, the most significant two-way interaction for tomato seeds, while no interactions were significant when chicory seeds were used. 相似文献
732.
733.
大港油田氧化塘生物处理采油废水 总被引:1,自引:0,他引:1
大港油田采用氧化塘生物处理技术对采油废水进行处理,经过五年的运行实践表明,处理效果显著,去除率逐年提高,运行稳定。COD、石油类、SS去除率2000年至2004年分别由43%、51%、-14%提高到77%、98%、26%。氧化塘生物处理技术投资少、运行费用低,处理成本小于0.2元/m3。 相似文献
734.
在分析夹潦草堂旅游风景区背景要素和制约因素的基础上,遵循史学文化、知识、淳真自然的三大设计理念,采用圈层递进的总体布局构思,设计了7个主题区域的空间布局,开发出修学旅游、观光旅游、度假旅游、森林探险旅游等四大主导旅游产品。 相似文献
735.
736.
Karel De Greef Frans Stafleu Carolien De Lauwere 《Journal of Agricultural and Environmental Ethics》2006,19(1):57-66
Public debate on acceptable farm animal husbandry suffers from a confusion of tongues. To clarify positions of various stakeholder
groups in their joint search for acceptable solutions, the concept of animal welfare was split up into three notions: no suffering,
respect for intrinsic value, and non-appalling appearance of animals. This strategy was based on the hypothesis that multi-stakeholder
solutions should be based on shared values rather than on compromises. The usefulness of such an artificial value distinction
strategy was tested in a small series of experiments. The results demonstrate that the chosen concept to distinguish between
values is effective in a stakeholder context. Farmers’ views on doing good to animals appeared to be largely based on their
value to prevent suffering and predominantly focused on the provision of regular care. Their priority for this value is clearly
shared with other stakeholders, providing a basis for joint solutions. The concept of intrinsic value does not play a discernable
role in farmers’ considerations. Based on the varying views on welfare, it can be inferred that there is a gradual rather
than a principal difference between government legislation and farmers’ values, whereas public perception and acceptance of
farm practices remains complicated. Distinction between value groups and focusing on a selected notion (such as no suffering)
proved to be effective in bringing representatives of stakeholder groups together, but is unlikely to bridge the emotional
gap between commercial farm practices and public ideals. 相似文献
737.
Stratification and Circulation in a Shallow Turbid Waterbody 总被引:1,自引:0,他引:1
Shallow waterbodies are often assumed to be well mixed in the vertical. However, when they are characterised by high turbidity levels, absoption of solar heating within a relatively thin surface layer can produce thermal stratification. Results from an intensive monitoring program have been combined with three-dimensional circulation modelling to examine the diurnal stratification cycles in a small turbid waterbody. The waterbody, known as Rushy Billabong, is located in southeastern Australia and its high turbidity coupled with forcing by wind and solar radiation resulted in regular diurnal cycles of stratification and overturning. Under conditions of light wind and high solar radiation, the model results were generally consistent with the observed temperature field. However, under stronger winds, preferential cooling and sinking of shallow water around the edge of the lake began to contribute significantly to the interior stratification. Model estimates then became more sensitive to the detailed bathymetry and the choice of turbulence parameterisation. The level of stratification is also shown to influence the circulation in the billabong by trapping the wind-driven flow near the surface. Insights provided by the observations and modelling may have broader implications for the management of small turbid systems such as settling ponds, aquaculture ponds, and some natural wetlands. 相似文献
738.
Steve H. Hanke Lennart de Mare 《Journal of the American Water Resources Association》1982,18(4):621-626
Shortcoming associated with past water demand studies are evaluated. To overcome these shortcomings, pooled, time series, cross section data from -6, Sweden, are used in an ordinary Least squares analysis to estimate the demand for residential water. Elasticities for five variables, including price and income, are estimated. An approach for the conduct of future water demand studies is suggested. 相似文献
739.
William A. Jury Gideon Sinai Lewis H. Stolzy 《Journal of the American Water Resources Association》1979,15(5):1444-1458
ABSTRACT: Electric generation facility water requirement will increase substantially in the future in the Western United States because new power plants are to be constructed at inland sites rather than on the coast. At the inland locations, power plants will have to compete with agriculture and public users for fresh water supplies, and will be constrained by environmental legislation to dispose of cooling waste water in lined evaporation ponds. The various options for power plant cooling are analyzed in respect to cost, water consumption, and environmental hazard, and also in respect to their compatibility with existing state and federal regulations. Several proposals for balancing the water requirements of various users in water-scarce areas are reviewed and criticized. 相似文献
740.
直线电机轮轨系统采用直线感应电机牵引 ,轮轨系统支承导向 ,是一种在技术、经济、环保方面均具有良好性能的新型城市轨道交通系统。该系统有两种主要技术模式 ,均有良好的安全运营记录。笔者介绍了系统的性能和设计特点 ;从牵引制动系统、控制系统、管理系统、养护维修系统以及防灾系统 5个方面对系统的安全性设计方法进行了总结 ;认为该系统具有良好的安全性能 ,先进的安全管理理念以及健全的安全防护系统 ;特别强调对该系统进行的安全设计研究 ,将为提高我国城市轨道交通系统的安全性提供新的思路 相似文献