生物滞留系统处理水产养殖尾水的效能和机制

为探究生物滞留系统(bioretention system,BS)对水产养殖尾水的处理效能,设计并构建倒置(inverted bioretention system,IBS)和正置(control bioretention system,CBS)2组生物滞留系统,在不同进水条件下比较了2种BS构建方式的运行效能,通过胞外聚合物(EPS)、三维荧光光谱和电子传递活性(ETSA)等方法阐述了不同构建方式下BS的脱氮机制。结果表明：在不同进水条件下IBS的处理效能优于CBS,当运行间隔周期为1 d时,IBS的TN和NO₃⁻-N去除率分别达到71.79%~82.00%和68.70%~85.84%,平均去除率比CBS分别高出10.65%和15.89%。CBS和IBS的TN和NO₃⁻-N去除率随进水负荷的增加呈先升高后稳定的趋势,TP波动最小,去除率均稳定在97.04%~99.22%。构建方式对EPS的组分无明显影响,但对EPS含量和ETSA影响显著。IBS的构建方式可促进微生物分泌更多的EPS,其中EPS的多糖(PS)和蛋白质(PN)含量分别比CBS高出66.89 ug·g⁻¹和603.24 ug·g⁻¹,并且IBS的酪氨酸、色氨酸和微生物代谢产物明显高于CBS;此外,与CBS的ETSA为(0.47±0.07) ug·(g·min)⁻¹,相比IBS提高了0.35 ug·(g·min)⁻¹。以上研究结果为应用生物滞留系统技术处理养殖尾水提供参考。     

纳米金属对污水处理系统中磺胺耐药基因和耐药菌的影响及其机理

细菌耐药性和纳米材料污染为新兴环境问题。细菌耐药性遗传载体——耐药基因 (ARGs) 广泛存在于污水处理系统中,且已被证明与金属纳米材料密切相关。采用实时荧光定量PCR技术,探究了纳米零价铁 (nZVI) 和纳米氧化锌 (nZnO) 对污水处理系统中磺胺类耐药菌 (ARB) 和ARGs的分布特征的影响。结果表明,50 mg·L⁻¹ nZVI和nZnO暴露均有利于削减磺胺ARB浓度数。与对照组相比,nZVI和nZnO暴露后污泥中sul1丰度增加了0.25%~16.21%,而sul2出现明显削减 (1.51%~15.47%) 。此外,50 mg·L⁻¹ nZVI会导致游离态胞外ARGs大幅削减。nZVI和nZnO暴露通过富集污水处理系统中的intI1、改变细胞膜通透性和调节细菌转录能力促进sul1的增殖。本研究结果阐明了典型纳米金属对污水处理系统中ARB和不同形态ARGs消长的影响及其机制,可为制定有效调控和全面削减污水处理系统中耐药污染策略提供参考。     

中国环境监测信息产品的主要问题及发展方向

基于中国环境监测信息产品的发展现状,针对信息产品生产流程的监测数据生成、监测数据加工、信息产品服务3个阶段分别指出存在的主要问题,并提出未来需全面提升环境监测信息产品的科学性、准确性、敏感度、服务对象满意度以及信息供给普惠度。     

海绵城市生物滞留带重金属污染特征及风险评价

生物滞留带作为海绵城市重要的净水和渗水措施,在全国海绵城市建设中得到了广泛的应用.为了探明生物滞留带重金属累积、污染和可能存在的环境风险,以全国首批海绵城市建设示范区重庆市悦来新城生物滞留带为研究对象,探讨其重金属含量与空间分布特征,利用污染系数、地质累积指数和潜在生态风险指数进行污染水平和生态环境风险评价.结果表明,悦来新城生物滞留带中除Mn外,Cu、Zn、Pb、Ni和Cd的含量平均值均超出重庆市土壤背景值的4.14、1.77、4.98、1.23和6.51倍.空间分布上,不同功能区域道路旁的生物滞留带重金属含量呈现出较大差异性,工业区道路生物滞留带中Cu、Zn、Mn、Pb、Ni和Cd的含量均显著高于其他区域生物滞留带中的同种类重金属含量（P<0.05）.污染系数和地质累积指数显示重金属的污染水平排序为：Mn相似文献   

多情景分析的农业面源污染关键源区识别软件开发及应用

为解决农业面源污染关键源区识别过程中情景单一、数据量大、涉及环节多,以及模型复杂、操作繁琐和治理效果不明确等问题,采用GIS技术结合InVEST的产水量与营养物传输率模型,构建可进行农业面污染关键源区识别与治理模拟的信息系统。设计了基于入河负荷、潜在径流浓度、负荷与产水量比值3种不同情景下的关键源区识别功能,模拟了3种情景下关键源区的分布状况;整合了InVEST的产水量、营养物传输率和流失负荷等模型;设计了面源污染关键源区治理模拟功能,可直观展示3种情景下识别出的关键源区的治理效果;并以海河流域为例,应用该软件对农田总氮（TN）面源关键源区进行了识别和模拟治理。结果表明：1）基于入河负荷情景下识别出的关键源区较为分散,分布在除永定河与子牙河水系外的大部分水系;基于潜在径流浓度情景下的关键源区分布较为集中,多分布在流域中部至南部,其余分布在东南部;基于负荷与产水量比值情景下识别出的关键源区分布高度集中,分布在流域中部至南部。2）基于潜在径流浓度、负荷与产水量比值情景在TN、总磷（TP）模拟治理中的效果接近,且明显优于基于入河负荷情景;结合软件中设定的基于入河负荷、潜在径流浓度、负荷与产水量比值3种情景进行分析,能降低复杂地理环境带来的影响,提高面源污染关键源区的识别效率,提升面源污染关键源区治理决策的科学性,具有实用性。

     

环境监测实验室信息管理系统的构建与实施

阐述了环境监测实验室信息管理系统(LIMS)的构建目标,介绍了系统的业务流程、总体设计及实施条件.提出建立环境监测LIMS系统,可提高分析数据的准确性和质量管理水平,全面提升实验室信息运转效率和管理水平,更好地为环境管理服务.     

中国省级环境信息系统设计

介绍覆盖２７个省的中国省级环境信息系统的总体设计、基本结构、主要内容,开发过程和特点,在环境信息资源管理战略规划和规范化研究的指导下,采用结构化生命周期思想同快速原型开发方法相结合的方式,开发了若干基础数据库,环境管理模块和决策支持模块,建成的系统基本达到技术先进、功能实用、设计规范、管理方便的要求,为进一步建设我国的环境信息网络打下了基础。     

基层环保部门环境信息公开存在的问题及对策

《环境信息公开办法(试行)》将从2008年5月1日起正式施行。对环境保护行政主管部门来说,公开环境信息,加强与公众的沟通,接受公众的监督,是当前进一步推进政府公共管理和服务职能转变的要求,是当前强化环境执法、提升环保部门管理水平的迫切需要。本文系统地分析了基层环保部门环境信息公开工作现状,针对实际工作中存在的问题,提出了解决对策。     

Assessing Watershed-Scale, Long-Term Hydrologic Impacts of Land-Use Change Using a GIS-NPS Model

Land-use change, dominated by an increase in urban/impervious areas, has a significant impact on water resources. This includes impacts on nonpoint source (NPS) pollution, which is the leading cause of degraded water quality in the United States. Traditional hydrologic models focus on estimating peak discharges and NPS pollution from high-magnitude, episodic storms and successfully address short-term, local-scale surface water management issues. However, runoff from small, low-frequency storms dominates long-term hydrologic impacts, and existing hydrologic models are usually of limited use in assessing the long-term impacts of land-use change. A long-term hydrologic impact assessment (L-THIA) model has been developed using the curve number (CN) method. Long-term climatic records are used in combination with soils and land-use information to calculate average annual runoff and NPS pollution at a watershed scale. The model is linked to a geographic information system (GIS) for convenient generation and management of model input and output data, and advanced visualization of model results. The L-THIA/NPS GIS model was applied to the Little Eagle Creek (LEC) watershed near Indianapolis, Indiana, USA. Historical land-use scenarios for 1973, 1984, and 1991 were analyzed to track land-use change in the watershed and to assess impacts on annual average runoff and NPS pollution from the watershed and its five subbasins. For the entire watershed between 1973 and 1991, an 18% increase in urban or impervious areas resulted in an estimated 80% increase in annual average runoff volume and estimated increases of more than 50% in annual average loads for lead, copper, and zinc. Estimated nutrient (nitrogen and phosphorus) loads decreased by 15% mainly because of loss of agricultural areas. The L-THIA/NPS GIS model is a powerful tool for identifying environmentally sensitive areas in terms of NPS pollution potential and for evaluating alternative land use scenarios for NPS pollution management.     

Benefits of Collaborative Learning for Environmental Management: Applying the Integrated Systems for Knowledge Management Approach to Support Animal Pest Control

Resource management issues continually change over time in response to coevolving social, economic, and ecological systems. Under these conditions adaptive management, or “learning by doing,” offers an opportunity for more proactive and collaborative approaches to resolving environmental problems. In turn, this will require the implementation of learning-based extension approaches alongside more traditional linear technology transfer approaches within the area of environmental extension. In this paper the Integrated Systems for Knowledge Management (ISKM) approach is presented to illustrate how such learning-based approaches can be used to help communities develop, apply, and refine technical information within a larger context of shared understanding. To outline how this works in practice, we use a case study involving pest management. Particular attention is paid to the issues that emerge as a result of multiple stakeholder involvement within environmental problem situations. Finally, the potential role of the Internet in supporting and disseminating the experience gained through ongoing adaptive management processes is examined.