区域环境空气质量预报的一般方法和基本原则

为响应公众服务和环境管理对环境空气质量预报的迫切需求,中国环境监测总站率先在京津冀区域开展了区域环境空气质量预报测试。结合目前积累的预报经验和国内外相关研究,探索出区域空气质量预报的一般方法和基本原则,讨论了客观订正环节中大气扩散条件、污染源排放、物理化学过程和空气质量变化规律的分析方法及系统建立、结果确定、天气控制形势分析和信息表述等基本原则,以期为各地开展环境空气质量预报提供技术参考。     

测定地表水中悬浮物的空白校正

进行了测定地表水中悬浮物空白校正与不作空白校正的对比试验 ,得出不作空白校正存在较大误差 ,认为测定地表水中悬浮物时应作空白校正。同时用测定海水中悬浮物的方法作测定地表水中悬浮物的试验 ,试验效果较好 ,符合测定要求。建议可用测定海水中悬浮物的方法来测定地表水中悬浮物     

碱性过硫酸钾消解紫外分光光度法测定水中微量总氮影响因素分析

采用国标《碱性过硫酸钾消解紫外分光光度法》（ HJ 636-2012）测定水中总氮（ TN）,虽然实验步骤简单,但影响因素较多,需严格控制实验条件。本文针对含量在方法检出限0．05 mg/L附近的微量总氮水样,从实验用水、器皿的处置、试剂的配制与存放、消解样品的制作与冷却时间等方面考察了总氮空白值的控制、校准曲线的选取等影响因素,优化了实验条件,结果令人满意。     

Integral transform solutions for atmospheric pollutant dispersion

A transient two-dimensional advection–diffusion model describing the turbulent dispersion of pollutants in the atmosphere has been solved via the Generalized Integral Transform Technique (GITT), by two different schemes. The first approach performs numerical integration of the transformed system using available routines for initial value problems with automatic error control. In spite of the time-consuming character of such a scheme, its flexibility allows the handling of problems involving time-dependent meteorological parameters such as wind speed and eddy diffusivities. The second approach works fully analytically being thus intrinsically more robust and economic, although not directly applicable in dealing with time-dependent parameters. For the test problem used in this work, both methods agree very well with each other, as well as with a known analytical solution for a simpler formulation used as benchmark. The impact of the longitudinal diffusivity on the stiffness of the ordinary differential equation (ODE) system arising from the integral transformation has been assessed through the processing time demanded to solve it when the numerical approach is used. The observed CPU times show that the analytical approach is clearly preferable unless the problem involves time-dependent parameters.     

臭氧一级校准数据读取方式对校准的影响研究

臭氧标准参考光度计同时采用串口连接模式、模拟信号连接模式和仪器数据存储-手动输入模式3种数据读取方式对臭氧二级传递标准进行一级校准,比较不同数据读取方式对校准结果的影响。串口连接模式和仪器数据存储-手动输入模式所得到校准曲线的斜率和截距具有很好的一致性,相差较小。经修正转化截距后的模拟信号连接模式所得到的斜率和截距相对于其他2种数据读取方式有一定的差别,但也在校准指标以内。     

The Seasonal Variation of the Concentrations of Ozone, Sulfur Dioxide, and Nitrogen Oxides in Two Nigerian Cities

A combination of multivariate statistical methods including factor analysis, principal component analysis, principal component regression, and multiple linear regression (MLR) were employed to evaluate the influence of seasons on the concentrations of ozone, sulfur (IV) oxide, and oxides of nitrogen in ambient air of Nigerian cities of Lagos and Ilorin. The former city is located in the coastal area, and it is highly congested with a high intensity of marine, vehicular, and industrial activities, and the latter city is a medium size town, located in the central guinea savannah zone of Nigeria. Samples were collected using a high-volume sampler from near the ground at various sites of diverse human and industrial activities, during wet and dry seasons from 2003 to 2006. The PCA reveals three distinct groupings during the day for all data, which is a reflection of different factors contributing to the atmospheric chemistry of these cities. The predicted ozone concentration values by MLR agree fairly well with the measured data. The dependence of ozone on meteorological parameters including relative humidity, air temperature, and sun exposure and the precursor pollutants depends on weather and the anthropogenic activities. The results for the two cities indicate that reduction in the level of NO₂ is accompanied by an increase in the level of ozone, suggesting the interconversion between the two via photochemical activity.     

Application of a DPSIR Modeling Framework to Assess Spatial–Temporal Differences of Water Poverty in China

Water shortage is a common problem around the world, especially in developing countries. Water shortage is closely linked to natural and social conditions, but the linkages between these natural and social conditions and their underlying temporal and spatial variation are less well explored. This paper details an application of the Driving‐Force‐Pressure‐State‐Impact‐Response (DPSIR) model, a holistic and sustainable tool for resources planning and management, and uses comprehensive weights to evaluate the water poverty (wp) in China from 1997 to 2014. This study applies the Kernel density estimation model to analyze the temporal variation trend and uses the least square error model to analyze the spatial pattern of wp. The results show the level of wp is gradually declining over time and the improvements in the coastal and inland wp situation are not spatially harmonious, and there are four primary types of wp in China based on drivers and causal mechanisms: D‐P‐I, D‐P‐I‐R, D‐P‐S‐I, and D‐P‐S‐I‐R. Furthermore, we analyze the main causes of spatial difference of wp and put forward corresponding countermeasures. The research findings are intended to provide a new insight for the evaluation of wp in the context of sustainable development, breaking past limitations that arise in simplified analyses using a single method, and to provide a strategy for regional water resources management to relieve wp.     

Human–wildlife coexistence in a changing world

Human–wildlife conflict (HWC) is a key topic in conservation and agricultural research. Decision makers need evidence-based information to design sustainable management plans and policy instruments. However, providing objective decision support can be challenging because realities and perceptions of human–wildlife interactions vary widely between and within rural, urban, and peri-urban areas. Land users who incur costs through wildlife argue that wildlife-related losses should be compensated and that prevention should be subsidized. Supporters of human–wildlife coexistence policies, such as urban-dwelling people, may not face threats to their livelihoods from wildlife. Such spatial heterogeneity in the cost and benefits of living with wildlife is germane in most contemporary societies. This Special Section features contributions on wildlife-induced damages that range from human perspectives (land use, psychology, governance, local attitudes and perceptions, costs and benefits, and HWC and coexistence theory) to ecological perspectives (animal behavior). Building on current literature and articles in this section, we developed a conceptual model to help frame HWC and coexistence dimensions. The framework can be used to determine damage prevention implementation levels and approaches to HWC resolution. Our synthesis revealed that inter- and transdisciplinary approaches and multilevel governance approaches can help stakeholders and institutions implement sustainable management strategies that promote human–wildlife coexistence.     

新世纪以来国内外生态农业综合评估研究进展

在梳理了新世纪以来国内外文献的基础上,对生态农业的概念进行了溯源与辨析,系统总结了国内外学者对生态农业综合评估指标选取和指标体系建立的主要思路,将现有评估体系归纳为EES框架及其拓展和PSR、DSR模型两类,对评估研究所采用的主要指标进行了频度统计、讨论和中外对比。概括了当前研究中采用的权重确定与综合评估的主要方法并进行了优缺点比较。从农业特征、空间尺度、时间跨度等角度对国内外已有的实证研究进行了分类与总结。研究比较发现,国内生态农业评估在实际指标的选取中,往往将数据易得性放在首要位置,而缺乏对指标之间内在逻辑联系和指标合理性、有效性的审视,指标体系构建缺乏代表性和概括性。此外,在对生态概念的理解上,现有评估体系对农业生产环节的生态影响挖掘的并不深刻,对石油消耗、电力消耗尤其是碳排放等重要的间接生态影响存在遗漏。最后,针对现有农业生态评估存在的问题,研究提出六方面的建议:1鉴于全球气候变化影响的广泛和深入,考察我国和各地区的生态农业需要具有全球视野,应当将农业碳汇/碳源的测度和评估纳入到生态农业综合评估体系中;2评估时应当把握好农业生产效率的提升与生态环境保护两者之间的关系;3重视对农业生态模式和类型的辨识;4以我国农业发展阶段特征作为指标体系设计的基石,避免直接移植国外文献中的指标体系;5注重综合评估的案例导向性,并结合多源异构数据的优势来提高评估准确度;6注重对生态农业发展和变迁情况的长期性、复杂性和综合性的考量,提高评估的空间尺度和时间跨度。     

Toxicity assessment of 2,4-D and MCPA herbicides in primary culture of fish hepatic cells

In this study, we used primary cultures of fish hepatic cells as a tool for evaluating the effects of environmental contamination. Primary hepatic cell cultures derived from the subtropical fish Metynnis roosevelti were exposed to different concentrations (0.275, 2.75 and 27.5 μg L^?1) of the herbicides 2,4-dichlorophenoxyacetic acid (2,4-D) and 4-chloro-2-methylphenoxyacetic acid (MCPA). Cellular respiratory activity was evaluated by polarography using three substrates: 0.5 M glucose, 0.5 M succinate and 0.5 M α-ketoglutarate. Significant changes were observed in cellular oxygen consumption with 0.5 M α-ketoglutarate. Even at low concentrations, 2,4-D and MCPA were potent uncouplers of oxidative phosphorylation. Primary cultures of M. roosevelti liver cells may provide a useful tool for the evaluation of environmental contaminant effects. A review of regulations regarding permitted concentrations of these herbicides is needed.