开封市公园灰尘重金属含量及潜在生态风险

采集河南省开封市区4个典型公园(清明上河园、龙亭公园、铁塔公园、相国寺)52个地表灰尘样品,采用原子荧光(AFS)法、电感耦合等离子体发射光谱法(ICP)和电感耦合等离子体质谱(ICP-MS)法测定灰尘重金属含量,并用调整后的Hkanson潜在生态危害分级标准对重金属潜在生态危害进行评价。结果表明:灰尘Cd、Hg、Pb、Zn、Cu富集显著。重金属单项生态风险指数(E)顺序为HgCdPbCuNiZnCoCrMnTi,除Hg和Cd出现强烈以上生态风险外,其他重金属风险轻微。所有公园灰尘重金属潜在生态总风险(RI)均在很强等级以上,其大小依次为RI相国寺RI龙亭公园RI铁塔公园RI清明上河园。灰尘Hg和Cd对RI的平均贡献率分别为45.28%和46.77%,是最主要的风险因子。     

土壤释汞通量影响因素研究进展

汞具有独特的物理化学性质和生物毒性,能在大气中长期滞留,对距离污染源较远的地区造成污染。土壤是一个巨大的汞库,土壤和大气界面汞的交换是汞的生物地球化学循环的重要组成部分,能够对周围环境产生显著的影响。土壤释汞通量受到很多环境因素的影响,如土壤中汞的形态、土壤和大气中汞含量、土壤温度、光照、土壤湿度、降雨和灌溉、土壤p H和Eh、植被、气象因素、微生物等。环境因素的变化可能会导致土壤释汞通量的昼夜变化和季节变化。环境因素通常对土壤释汞通量进行复合影响,而最终的影响结果可能表现为协同或是拮抗作用。本文对影响土壤释汞通量的主要因素及其影响机理进行了详细地介绍,提出了对各种环境因素的复合效应的结果的研究需要进一步开展。     

基于P-S-R框架辽宁省2003年-2012年城市生态安全演变趋势研究

着眼于辽宁省经济发展与环境问题凸显的现状,基于压力-状态-响应(P-S-R)生态安全评价模型,选取辽宁省14个城市2003年-2012年的经济、社会与环境等25个指标数据进行生态安全综合评价,对生态安全演变趋势进行分析.结果表明:十年来辽宁省城市生态安全指数呈现整体上升趋势,生态安全综合评价指数基本与生态安全指数变化趋势相似,说明辽宁省生态安全状况正逐步改善,并且总体呈现发展趋势,辽宁省的生态安全建设取得一定进展.     

生活垃圾焚烧飞灰中重金属浸出影响研究

通过浸出液pH测定、全量测定以及(HJ/T 299-2007)硫酸硝酸法和(HJ/T 300-2007)醋酸缓冲溶液法浸提,对生活垃圾焚烧飞灰中重金属浸出特性进行了实验研究.结果表明浸出pH条件、飞灰中重金属含量以及重金属分布形态是影响浸出浓度的主要因素.相比于硫酸硝酸法,醋酸缓冲溶液法重金属提取效率明显较高,尤其是铜锌镉铬.垃圾焚烧飞灰潜在环境风险较大,在填埋处理及综合利用时应充分考虑其浸出特性.     

海南省麒麟菜自然保护区麒麟菜资源研究

2012年对海南省麒麟菜保护区内野生麒麟菜资源进行调查研究。结果表明,海南省麒麟菜自然保护区有琼枝和耳突卡帕藻2种麒麟菜,优势种为琼枝。保护区内麒麟菜分布面积约为19.40 km2,平均覆盖度为0.54%,平均生物量为7.30 g/m2。其中文昌海域约为14.35 km2,平均覆盖度为0.55%,平均生物量为7.85 g/m2;琼海海域约为5.05 km2,平均覆盖度为0.49%,平均生物量为5.78 g/m2。伴生生物有33科50种,其中多毛类有9科14种,软体动物有14科17种,甲壳类9科18种以及棘皮动物1科1种,平均生物量为6.38 g/m2,平均栖息密度为72.72个/m2。优势种为斑纹围沙蚕、地中海巨亮钩虾、雷氏藻钩虾和四肢舟钩虾。受草食性动物、渔业活动、陆源污染和海洋工程影响海南省麒麟菜保护区麒麟菜大面积减少。     

The gap report of global climate change mitigation,finance, and governance after the United States declared its withdrawal from the Paris Agreement

On 1 June 2017, the US President Donald Trump officially announced the withdrawal from the Paris Agreement, thus the study on the reasons of withdrawal, the potential impacts, and coping strategies has become a focus among policy circles and of the international community. Based on the self-developed US Policy Assessment Model, this paper systematically evaluates the three potential “major deficits” in terms of mitigation, climate finance, and global climate governance, as a result of the US withdrawal from the Paris Agreement and puts forward policy suggestions for coping with such transformations accordingly. The study shows that the United States ’withdrawal from the Paris Agreement will affect the existence and implementation of successive climate policies and result in an additional 8.8–13.4% increase in the global emissions reduction deficit. The United States’ withdrawal will also deteriorate the existing climate finance mechanism. The Green Climate Fund (GCF)’s funding gap will increase by US$2 billion, while the gap of long-term climate finance will increase by about US$5 billion a year. Either the China–EU or the “BASIC plus” mechanism could fill the governance deficit caused by the United States and the lack of political momentum may continue for a while in the future.     

<Emphasis Type="Italic">Cochlodinium polykrikoides</Emphasis> blooms and clonal isolates from the northwest Atlantic coast cause rapid mortality in larvae of multiple bivalve species

Globally, many commercial bivalve populations have declined in recent decades. In addition to overharvesting and habitat loss, the increasing frequency and intensity of harmful algal blooms (HABs) are likely to contribute to bivalve losses, particularly in cases where blooms negatively impact larval stages. This paper reports on the lethal effects of clonal cultures and blooms of Cochlodinium polykrikoides from the US Atlantic coast on the larvae of three species of commercially and ecologically valuable bivalves: the Eastern oyster (Crassostrea virginica), the bay scallop (Argopecten irradians), and the Northern quahog (hard clam; Mercenaria mercenaria). Both cultures and blooms of C. polykrikoides were highly toxic to all three species of bivalve larvae causing 80–100% mortality during 24- to 72-h exposures at concentrations of 1–2 × 10³ cells ml⁻¹. Toxicity was dependent on cell densities, growth stage of C. polykrikoides (i.e. cultures in exponential stage growth were more toxic than later stages), exposure time of larvae to cells (i.e. longer exposure caused higher mortality), the age of larvae (i.e. younger larvae were more sensitive), and the relative abundance of C. polykrikoides (i.e. the presence of other microalgae decreased toxicity). Free radical-scavenging enzymes (peroxidase and catalase) and the removal of C. polykrikoides cells (i.e. culture filtrate) significantly increased larval survival suggesting toxicity is maximized by contact with live cells and may involve labile toxins bound by these compounds including e.g. reactive oxygen species. The toxicity of C. polykrikoides to bivalve larvae was generally more severe than other HAB species (e.g. Karenia brevis, Karlodinium veneficum, Alexandrium tamarense, Prorocentrum minimum). Since the bivalves in this study spawn in the months when C. polykrikoides blooms on the east coast of North America, these results suggest that these blooms may have detrimental effects on efforts to restore these already diminished populations.     

冷却塔的噪声特性与控制

某住宅小区建有大型冷却塔,运行时产生的噪声严重干扰了居民的生活。在现场进行噪声测量的基础上,着重分析了冷却塔的噪声特性以及噪声源,进而设计并详细分析了针对不同噪声源的噪声治理方案。实施结果证明,采取的控制措施有效,降噪效果明显,能完全满足国家技术标准的要求。     

湘西金矿沃溪矿区通风系统改造研究

基于矿井目前通风系统存在的问题,运用子域分区单元子系统通风方式、不同类型的中段通风网路、风流净化、入风流预冷、自然风压的合理利用等技术对通风系统进行 了优化改造.系统改造后,风量充足,风流稳定,通风能力与生产能力相适应,较好地解决了深部通风问题,取得了显著的技术效果和节能效益.     

Atmospheric oxidation capacity in the summer of Houston 2006: Comparison with summer measurements in other metropolitan studies

Both similarities and differences in summertime atmospheric photochemical oxidation appear in the comparison of four field studies: TEXAQS2000 (Houston, 2000), NYC2001 (New York City, 2001), MCMA2003 (Mexico City, 2003), and TRAMP2006 (Houston, 2006). The compared photochemical indicators are OH and HO₂ abundances, OH reactivity (the inverse of the OH lifetime), HO_x budget, OH chain length (ratio of OH cycling to OH loss), calculated ozone production, and ozone sensitivity. In terms of photochemical activity, Houston is much more like Mexico City than New York City. These relationships result from the ratio of volatile organic compounds (VOCs) to nitrogen oxides (NO_x), which are comparable in Houston and Mexico City, but much lower in New York City. Compared to New York City, Houston and Mexico City also have higher levels of OH and HO₂, longer OH chain lengths, a smaller contribution of reactions with NO_x to the OH reactivity, and NO_x-sensitivity for ozone production during the day. In all four studies, the photolysis of nitrous acid (HONO) and formaldehyde (HCHO) are significant, if not dominant, HO_x sources. A problematic result in all four studies is the greater OH production than OH loss during morning rush hour, even though OH production and loss are expected to always be in balance because of the short OH lifetime. The cause of this discrepancy is not understood, but may be related to the under-predicted HO₂ in high NO_x conditions, which could have implications for ozone production. Three photochemical indicators show particularly high photochemical activity in Houston during the TRAMP2006 study: the long portion of the day for which ozone production was NO_x-sensitive, the calculated ozone production rate that was second only to Mexico City's, and the OH chain length that was twice that of any other location. These results on photochemical activity provide additional support for regulatory actions to reduce reactive VOCs in Houston in order to reduce ozone and other pollutants.