Agricultural drainage and wetland management in Ontario

Land drainage is recognized as an integral part of agricultural activity throughout the world. However, the increase in agricultural production has resulted in the loss of wetland functions and values. Therefore, wetland management and agricultural drainage illustrate the conflict between economic development and natural values. This research assesses the approval process for agricultural land drainage in Ontario, Canada, to determine how the benefits of increased agricultural production are balanced against the loss of wetland values. A permit review of drainage applications was conducted from 1978 to 1997 in Zorra Township, Ontario, Canada. Data collection also included the document reviews, interviews with government agencies and wetland evaluation files. The selected criteria include efficiency, equity, consistency and adequacy. The results indicate that while the process is efficient, fundamental problems remain with the bargaining process.     

Improving decision quality: Making the case for adopting next‐generation site characterization practices

Better site characterization is critical for cheaper, faster, and more effective cleanup. This fact is especially true as cleanup decisions increasingly include site redevelopment and reuse considerations. However, established attitudes about what constitutes “data quality” create many barriers to exciting new tools capable of achieving better characterization, slowing their dissemination into the mainstream. Traditional approaches to environmental “data quality” rest on simplifying assumptions that are rarely acknowledged by the environmental community. Data quality assessments focus on the quality of the analysis, while seldom asking what impact matrix heterogeneity has had on analytical results. Assessments of data quality typically assume that chemical contaminants are distributed nearly homogeneously throughout environmental matrices and that contaminant‐matrix interactions are well behaved during analysis. Yet, these assumptions seldom hold true for real‐world matrices and contaminants at scales relevant to accurate risk assessment and efficient remedial design. For the site cleanup industry to continue technical advancement, over‐simplified paradigms must give way to next‐generation models that are built on current scientific understanding. If reuse programs such as Brownfields are to thrive, the scientific defensibility of individual projects must be maintained at the same time as characterization and cleanup costs are lowered. The U.S. Environmental Protection Agency (EPA) offers the Triad Approach as an alternative paradigm to foster highly defensible, yet extremely cost‐effective reuse decisions. © 2003 Wiley Periodicals, Inc.     

准好氧填埋早期渗滤液特征浅析

本文基于室内垃圾模拟柱试验，分析了准好氧填埋早期垃圾渗滤液的产生过程及垃圾降解的机理，得出了启动期内垃圾渗滤液产量的变化趋势，总结出准好氧结构的部分优点，并针对早期准好氧渗滤液产量的特点作了相应的讨论。     

NITROGEN AND PHOSPHORUS CONCENTRATIONS IN FOREST STREAMS OF THE UNITED STATES1

ABSTRACT: Seventy to eighty percent of the water flowing in rivers in the United States originates as precipitation in forests. This project developed a synoptic picture of the patterns in water chemistry for over 300 streams in small, forested watersheds across the United States. Nitrate (NO₃^?) concentrations averaged 0.31 mg N/L, with some streams averaging ten times this level. Nitrate concentrations tended to be higher in the northeastern United States in watersheds dominated by hardwood forests (especially hardwoods other than oaks) and in recently harvested watersheds. Concentrations of dissolved organic N (mean 0.32 mg N/L) were similar to those of NO₃～, whereas ammonium (NH₄⁺) concentrations were much lower (mean 0.05 mg N/L). Nitrate dominated the N loads of streams draining hardwood forests, whereas dissolved organic N dominated the streams in coniferous forests. Concentrations of inorganic phosphate were typically much lower (mean 12 mg P/L) than dissolved organic phosphate (mean 84 mg P/L). The frequencies of chemical concentrations in streams in small, forested watersheds showed more streams with higher NO₃^? concentrations than the streams used in national monitoring programs of larger, mostly forested watersheds. At a local scale, no trend in nitrate concentration with stream order or basin size was consistent across studies.     

九寨沟旅游设施非点源污染人工降雨实验

对九寨沟国家公园的旅游设施(栈道和公路)进行了人工降雨试验的设计、操作和测试数据分析.模拟试验选择6处公路和栈道试验区,采用人工降雨方法模拟历时30min的降雨.试验中按3 min间隔对各试验场降雨径流带出的总磷负荷进行现场监测.对公路和栈道降雨径流和浓度特征分别进行了相似性和异同性分析.     

医疗垃圾焚烧飞灰中重金属浸出的影响因素

以四川某城市为例,对医疗垃圾焚烧飞灰进行了重金属的浸出特性实验,探讨了不同液固比、初始pH值及浸取剂对飞灰中重金属Cu、Zn、Pb、Cd、Ni的浸出影响.结果表明,重金属的浸出率随着液固比的增加而增加;重金属在酸性条件下较易浸出,而在碱性条件下渗滤较少;不同的浸取剂对重金属的浸出也有一定影响.     

Excel在灰色关联分析中的应用

介绍了灰色关联分析的一般步骤,并对其中分辨率的取值和权重的计算作了初步分析.在此基础上,通过将灰色关联分析方法编写成Excel VBA程序,并应用于铜锣山隧道出口端隧道水的来源识别,不仅在较大程度上简化了计算,而且也取得了良好的预期成果.     

毛叶山桐子培育新方法及其工程化研究

毛叶山桐子的人工培育困难，至今没有人工林地。本研究通过小型试验、扩大试验和工程化试验，对毛叶山桐子的育苗方法进行了系统研究，得出了毛叶山桐子育苗的最佳条件。     

A Hydrologic/Water Quality Model Applicati11

Abstract: This paper presents a procedure for standard application of hydrologic/water quality models. To date, most hydrologic/water quality modeling projects and studies have not utilized formal protocols, but rather have employed ad hoc approaches. The procedure proposed is an adaptation and extension of steps identified from relevant literature including guidance provided by the U.S. Environmental Protection Agency. This protocol provides guidance for establishing written plans prior to conducting modeling efforts. Eleven issues that should be addressed in model application plans were identified and discussed in the context of hydrologic/water quality studies. A graded approach for selection of the level of documentation for each item was suggested. The creation and use of environmental modeling plans is increasingly important as the results of modeling projects are used in decision‐making processes that have significant implications. Standard modeling application protocols similar to the proposed procedure herein provide modelers with a roadmap to be followed, reduces modelers’ bias, enhances the reproducibility of model application studies, and eventually improves acceptance of modeling outcomes.     

磷钼蓝分光光度法测定水中磷的改进

用硫酸亚铁铵和葡萄糖作为混合还原剂,建立了用分光光度法测定磷的方法,确定了最佳测定条件。在浓度为0.6mol/L的H2SO4介质中,硫酸亚铁铵-葡萄糖将磷钼杂多酸还原成杂多蓝,其最大吸收波长为820nm,表观摩尔吸光系数为1.38×104L/(mol·cm),PO3-4质量浓度在0～2.8mg/L范围内符合比耳定律,线性回归方程A=0.1453ρ 0.02744,相关系数(r)=0.9933。用硫酸亚铁铵-葡萄糖混合还原剂还原速度快,灵敏度高,产物稳定性好,线性范围宽。将该方法用于环境水样中磷的测定,结果令人满意。