西江年最高水位的神经网络预报模型

对西江洪水发生的特征进行分析表明，洪水发生频率高，具有明显阶段性特征，并与流域面雨量密切相关。利用前期环流场、海表温度（SST）场及环流特征量资料选择初选预报因子，然后对初选预报因子作EOF分解构造综合预报因子，结合人工神经网络方法建立了西江年最高水位预报模型，并对预报模型进行独立样本试验。结果表明，该预报模型对历史样本拟合精度高，试报效果明显好于传统的逐步回归模型，可在汛期预测业务中应用。     

淮河流域旱涝易发区农田的陆气相互作用——CO2通量、能量交换和水汽输送的季节变化特征

利用淮河流域旱涝易发区的安徽省寿县农田下垫面陆气相互作用观测试验资料,重点分析观测期内CO2通量、能量交换和水汽输送的季节变化,并讨论了与此有关的辐射分量通量、下垫面反射率、波恩比、能量闭合守恒、土壤温度和土壤湿度的季节变化.结果表明CO2通量、能量分配受地表农作物长势影响明显,其中,水稻灌浆、成熟期,被稻田吸收的CO2通量最大可超过2 mg·m-2·s-1,潜热通量达到正的极大值.稻田光合作用最旺盛时期吸收的CO2通量和释放的潜热通量均大于小麦田光合作用最旺盛时期的对应量.较大土壤热通量对应于较低的土壤水含量.试验观测期的下垫面平均反射率为0.14.作物生长期,稻田表面潜热是下垫面吸收能量的主要消费者,小麦田表面潜热和感热相当.能量闭合率ε的变化范围为0.4～1.     

紫外分光光度法在处理废水中的应用

根据二沉池出水特点，指出了以260nm紫外光(F260)评价处理二沉池出水的理论依据，然后确定了E260与COD的关系式为：E260=0．008COD 0．083。最后以E260为评价指标，比较了3种无饥混凝剂在不同pH值条件下对城市二沉池出水的COD去除效果，确定了最佳混凝剂为三氯化铁(FC)及混凝条件：pH4．5，投药量Fe^3 为32mg/L。     

焦化厂火灾应急预案的建立

从焦化生产的工艺以及产品的特性入手，分析了焦化厂潜在的火灾事故隐患以及发生事故的可能性，强调了焦化厂作为一个化工企业建立应急预案的必要性。阐述了建立应急预案的注意事项和内容。     

水入渗条件下边坡破坏离心模型试验研究

水的人渗能对土体强度产生较大的影响,它是造成边坡破坏的一个主要因素.不同含水量土质边坡的离心模型试验表明:边坡的破坏类型与其含水量大小有关,且主要存在两种破坏类型:一种是含水量较小时形成的拉裂缝破坏,另一种是含水量较大时形成的整体滑塌破坏;同时,含水量与边坡的最大稳定高度呈非线性关系.进一步的损伤力学分析表明,随着土体含水量的增加,损伤变量增大,并存在一个突变点;通过同离心模型试验结果比较,发现该突变点对应的含水量可作为两种破坏类型的判据.     

济南市水资源现状与可持续发展对策

济南市是资源型缺水城市,地表水遭到严重污染,已成为水质型缺水城市,导致地下水超采、地面沉降、泉水停涌等一系列环境、生态、经济问题,水资源已成为制约济南市发展的瓶颈因素.在对济南市水资源现状及相关问题进行详细分析的基础上,提出加强客水资源调用与管理、水资源循环利用、合理制定水价等水资源可持续利用的措施和对策.     

秦皇岛港污水回用工程出水水质标准的制定

污水深度处理后回用不仅节约水资源,也减少了大量污染物的排放,是一项一举多得的益事。秦皇岛港污水深度处理回用工程利用城市二级处理的污水,经深度生物处理后用于煤炭除尘,解决了除尘水源紧张的局面。本文就如何确定回用工程的出水水质指标及其标准进行了讨论,阐述了制定出水水质标准的基本原则。     

Modelling nitrogen fluxes at the landscape scale

The distribution and impacts of different nitrogen pollutants are inextricably linked. To understand the problem fully, the interactions between the different pollutants need to be taken into account. This is particularly important when it comes to abatement techniques, since measures to reduce emissions of one nitrogen pollutant can often lead to an increase in another. This project represents a step towards greater understanding of these issues by linking together new and existing nitrogen flux models into a larger framework. The modelling framework has been constructed and some of the nitrogen flows between fields, farms and the atmosphere have been modelled for a UK study area for typical farm management scenarios.     

Best management practices compliance monitoring approaches for forestry in the eastern United States

Many of the eastern states that have published best management practices (BMPs) or forest management guidelines have also developed compliance monitoring programs to assess the application of these BMPs or guidelines on public and private forest land. The approaches among these states to collecting on-site monitoring data (measuring compliance) and evaluating sites are variable. A survey of eastern states found that almost all southern states monitor application of BMPs, but proportionally fewer of the northern states have established compliance monitoring programs. The state forestry agencies provide the leadership for these programs in most of the eastern states. States that monitor tend to evaluate all public and private forest landowner categories located within their states. In general, northern states monitor a broader array of site resources (e.g., cultural resources, visual quality) as compared to southern states which focus on water quality and wetlands protection. However, northern states focus their monitoring on timber harvesting, forest road construction and maintenance as compared to southern states which tend to monitor a broader array of forest management activities (e.g., site preparation, reforestation). When selecting sites for monitoring, the most common approach is to select some sites from all landowner categories within the state. Many states do not specify any criteria to identify sites for monitoring so that all sites have an equal chance for selection. Some states do use specific criteria to filter sites for monitoring, most commonly size of forest management activity and proximity to water.     

An assessment of Mississippi's nonindustrial private forest landowners knowledge of forestry BMP's

This study examined the knowledge levels of Mississippi Non Industrial Private Forest (NIPF) landowners. Data were collected by passing out surveys to participants in Best Management Practices (BMP) educational programs held in conjunction with County Forestry Association (CFA) meetings across Mississippi. Ten CFA's participated in this study. Educational program participants were asked to fill out a survey with several demographic and BMP questions prior to the educational program. Results show that BMP program participants owned an average of 113 hectares, whereas the average Mississippi NIPF landowner owns 20 hectares. Responses to BMP related questions show that Mississippi NIPF landowners have a low level of knowledge concerning BMP's. This situation is likely similar to other states in the Southeastern United States. It can be assumed that county forestry association members are more active and informed about managing their forest land. Therefore, these results may overestimate the BMP knowledge level all landowners in Mississippi.Improved educational programs for NIPF landowners, along with better communication between foresters, loggers, and NIPF landowners are needed if BMP's are to be implemented effectively in Mississippi and across the southern region.