PRODUCTION PROCESSES UNDER THE ICE IN LAKE ST. CLAIR: 1. IRRADIATION AND TEMPERATURE1

ABSTRACT: Data from three ice-covered stations in Lake St. Clair were collected to evaluate the effect of ice and related variables on phytoplankton production. Primary production, phytoplankton standing crop, irradiation and temperature were measured from January to April, 1973. Mean production values ranged from 0.74 mgC/m³/h at station 1 near Mitchell Bay to 3.4 mgC/m³/h in waters at stations 2 and 3 below the Thames River mouth. A similar pattern was observed in chlorophyll a concentration, the mean values ranged from 0.63 μg/1 at station 1 to 2.1 and 1.3 μg/1 at stations 2 and 3. Temperature stratification occurred at the three stations. However, the temperatures at station 1 were consistently more than a degree warmer than at the other two stations. Irradiation was low, having a mean value at the sampling depth of .075 ly/min. The data is interpreted to indicate that the ice-bound phytoplankton were adapted to the low irradiation. It is suggested that the variation observed between stations is related to the formation of a plume by the Thames River and differences in nutrient loads carried by the St. Clair and Thames Rivers.     

DEVELOPING COMPETITION FOR WATER IN THE URBANIZING AREAS OF COLORADO1

ABSTRACT: Rapid population growth in the metropolitan area of Denver, Colorado, is causing conflicts over water use. Two cities, Thomton and Westminster, have begun condemnation proceedings against three irrigation companies to secure agricultural water rights for municipal use. This is the first condemnation proceeding against irrigation water rights for municipal use. Should the suit succeed, over 30,000 acres of presently irrigated land will lose its water supply. There are about four hundred landowners in the area; two hundred of these are commercial farmers, including truck, dairy and specialty farms. Total agricultural production amounts to about $8 million per year. About 561 jobs related to agriculture will disappear along with about $4 million in not income. Only 6.4 percent of the farmland along the Front Range is irrigated. Continued urban growth will put pressure on the water supply of much of this land. The interested parties of the region should cooperate to lessen the impact of urban growth on agricultural lands and water by forming a metropolitan water district. Such a district could share costs of development of additional municipal water and develop systems where municipalities would recycle waste water back to the irrigated lands.     

ENVIRONMENTAL FEATURES FOR FLOOD CONTROL CHANNELS1

ABSTRACT: The environmental effects of flood control channel modifications such as clearing and snagging, straightening, enlargement, and/or paving can be quite severe in some cases. Information review reveals that several environmental features have been incorporated into the design, construction, operation, or maintenance of recent flood control channel projects to avoid adverse environmental impacts and enhance environmental quality. Typically, these features have been proposed by conservation agencies and designed with minimal quantitative analysis. Environmental features for channel projects include selective clearing and snagging techniques, channel designs with nonuniform geometry such as single bank modification and floodways, restoration and enhancement of aquatic habitat, improved techniques for placement of excavated material, and revegetation.     

Emissions associated with meeting the future global wheat demand: A case study of UK production under climate change constraints

Climate change, population growth and socio-structural changes will make meeting future food demands extremely challenging. As wheat is a globally traded food commodity central to the food security of many nations, this paper uses it as an example to explore the impact of climate change on global food supply and quantify the resulting greenhouse gas emissions. Published data on projected wheat production is used to analyse how global production can be increased to match projected demand. The results show that the largest projected wheat demand increases are in areas most likely to suffer severe climate change impacts, but that global demand could be met if northern hemisphere producers exploit climate change benefits to increase production and narrow their yield gaps. Life cycle assessment of different climate change scenarios shows that in the case of one of the most important wheat producers (the UK) it may be possible to improve yields with an increase of only 0.6% in the emission intensity per unit of wheat produced in a 2 °C scenario. However, UK production would need to rise substantially, increasing total UK wheat production emissions by 26%. This demonstrates how national emission inventories and associated targets do not incentivise minimisation of global greenhouse gas emissions while meeting increased food demands, highlighting a triad of challenges: meeting the rising demand for food, adapting to climate change and reducing emissions.     

可持续发展中的清洁生产

传统工业生产方式在可持续发展背景下面临严峻挑战，清洁生产应而生，它是持续利用资源，减少工业污染，保护环境的根本措施，本文就清洁生产在中国示范推广所产生的经济，社会及环境效益进行了综合论述。     

Impacts of agri-environmental policy on land use and nitrogen leaching in Finland

Agri-environmental policies are challenging to be evaluated since they are often implemented in combination with other policies and regulations affecting agriculture. Also input and output markets affect agriculture. We provide impact assessment of agri-environmental scheme implemented in Finland 2007–2013 based on integrated economic and hydrological modelling and counterfactual scenarios. Development of crop specific fertilisation and land use changes, simulated using a multi-regional economic sector model, is included in a nutrient leaching model implemented in a typical agricultural region. Our results on agricultural production, land use, and nitrogen leaching show that the agri-environmental policy successfully mitigates nutrient leaching in intensive production regions but some mitigation potential is lost in less intensive regions.     

依托清洁生产促进环保产业良性发展

清洁生产作为一种全新的发展战略,借助各种相关理论和技术,在产品的整个生命周期的各个环节采取预防措施,通过将生产技术、生产过程、经营管理及产品等方面与物流、能量、信息等要素有机结合起来,优化运行凡事,实现最小的环境影响、最少的资源、能源使用,最佳的管理模式以及最优化的经济增长水平。结合现代环保意识的源起与企业实施清洁生产的成功案例,阐述人类要保护赖以生存的地球环境,推动环保产业良性健康发展,为社会经济活动提供必要的资源和能源,实现可持续发展,实施清洁生产是必由之路。     

基于综采面产尘分布与扩散分析的粉尘防治研究

在对W3709综采工作面产尘特点分析的基础上,将工作面产尘源分为落煤扬尘、落煤冲击产尘及割煤产尘3类。对采煤机顺风割煤与逆风割煤时粉尘运动规律进行了详细的分析,根据工作面产尘特点与粉尘运动规律,提出了包括煤层注水、采煤机割煤产尘治理与控制以及支架处粉尘治理一套完整的综合防尘系统。通过现场应用,工作面粉尘在原有设施降尘基础上降低86%以上,降尘效果良好,有效地解决了该工作面粉尘污染严重的难题。     

基于ARIMA的安全生产事故预测与实证研究

为了减少企业安全管理者在生产作业中由于不确定性导致错误决策所产生的风险,在企业历年安全生产事故数据基础上进行预测具有一定的现实意义。以某企业2008年至2011年的安全生产事故次数时序数据,采用EViews 5统计分析软件,基于ARIMA时间序列预测模型更加关注对事故发生是否平稳而相对于其他预测模型更关注于趋势研究的良好特点,建立安全生产事故ARIMA时序预测模型,并对2012年的安全生产事故发生次数进行预测,通过效果检验发现该模型预测结果基本上能够反映该企业安全生产事故发生的实际情况。通过ARIMA方法在某企业安全生产事故预测具体案例的实现,是对现有安全生产事故预测方法的补充和完善,可为企业安全管理和决策提供一定的指导。     

施工现场安全生产人员聚集性活动安全专项管理

施工安全生产风险是由风险事件概率和风险后果2个要素决定的。从施工安全风险后果,即潜在安全风险后果影响的人员角度,介绍了施工现场安全生产人员聚集性活动安全专项的系统管理方法。施工安全风险跟踪监控实践,表明该方法对促进安全生产绩效具有重要意义。