城市垃圾问题及处理对策

中国的城市垃圾问题已经成为比较严重的环境问题之一,目前的垃圾处理存在很多问题.以全过程控制思想为基础,在可持续发展和"三化"原则的指导下,运用环境管理的经济、法律、行政等方法,提出解决城市垃圾问题的城市垃圾管理对策和技术对策,提出了城市生活垃圾多元化综合处理的设想,以求建立适合中国国情的城市垃圾管理体系和垃圾产业化体系.     

EFFECTS OF PLACER MINING DISCHARGE ON HEALTH AND FOOD OF ARCTIC GRAYLING1

ABSTRACT: During the summers of 1982, 1983, and 1985, we assessed the effects of placer mining sedimentation on Arctic grayling, Thymallus arcticus, in the headwaters of Birch Creek, northeast of Fairbanks, Alaska. We compared differences between two streams (one that was undisturbed and one with mining activity upstream) near the confluence. Studies of caged fish demonstrated that, if grayling could not escape from streams carrying mining sediments, they would either die at high rates (sac fry) or suffer gill damage, starvation, and slowed maturation (age-O fingerlings and age-2 juveniles). Indirect effects of sedimentation, through loss of summer habitat for feeding and reproduction, may more severely affect grayling populations than the direct effects of sedimentation on the health and survival of individual fish.     

基于RuO2-IrO2/Ti和Fe0电极的电氧化-电絮凝处理含Tl废水

基于RuO₂-IrO₂/Ti形稳电极和Fe⁰牺牲电极实现电氧化-电絮凝(EO-EC)一体化处理含Tl (I)废水,并与单一的电絮凝(EC)进行比较,探讨了EO-EC处理含Tl废水的机理.结果表明,相较于单一EC,EO-EC (1:1)组合技术适应于宽pH (4-10)以及电流密度范围(5-20mA/cm²)下含Tl废水高效处理,且不易发生钝化;活性氯以及氧化还原电位在Tl (I)间接氧化Tl (III)过程中扮演重要角色,沉淀分析表明生成的Tl (OH)_3(s)与絮体Fe (OH)_3(am)共沉淀,纤铁矿位点可吸附残留Tl (I).EO-EC一体化技术可满足实际含Tl废水达标处理(<2µg/L)且具有经济可行性.     

HIV risk and prevention in emergency-affected populations: a review

While basic guidelines on HIV prevention in emergencies have been available for several years, international agencies involved in the provision of health services have not placed sufficient priority on the prevention of the human immune deficiency virus (HIV) and other sexually transmitted infections (STIs) in complex emergencies. This paper reviews the factors that may increase the risk of HIV transmission in populations affected by complex emergencies and outlines recommendations for research and programmes. Research into the most appropriate methods of carrying out HIV surveillance and interventions in these settings is needed. In the post-emergency phase programmes need to be far more extensive than those offered under the Minimal Initial Services Package (MISP). While the potential for stigmatization represents an important constraint, there is a need to prioritize HIV/STI interventions in order to prevent HIV transmission in emergency-affected populations themselves, as well as to contribute to regional control of the epidemic.     

Studies of primary productivity in coastal waters of southern Long Island,New York

Phytoplankton productivity of the tidal estuaries and coastal waters of southern Nassau Country, Long Island, New York, USA was determined monthly at 28 stations during 1966. Diatoms alternated with dinoflagellates in dominating the standing crop in the coastal area. The estuaries were characterized by sustained blooms of green flagellates and dinoflagellates during the spring/summer period, 1966. Chlorophyll a ranged from 1.0 to 27.6 mg/m³ in the estuarine area, and 1.45 to 10.15 mg/m³ in adjacent coastal waters. Rate of phytosynthesis per unit weight chlorophyll a for surface samples in the region under study a veraged from 3.1 to 3.5 mgC/mg chlorophyll a/h. At light saturation, however, the ratio varied according to water temperature and species' composition. Primary productivity decreased seawards, with mean values for 1966 of 0.35, 0.22, and 0.16 gC/m³/d for the estuarine, nearshore and offshore areas, respectively.This study was carried out at the Lamont Geological Observatory of Columbia University Palisades; New York, USA.The study was conducted with financial assistance from Nassau County, New York, and the G. Unger Vetlesen Foundation.     

泥石流灾情综合评估模式

泥石流灾情综合评估模式是在灾情绝对评估的基础上建立的。首先，建立了泥石流灾情评估的步骤框图；然后依据已有的泥石流灾情评估指标体系对各项指标进行量化分析处理，将得了各灾情评估指标公值分布及其量纲换算法，确定了反映直接损失的灾情绝对评估指标和相对评估指标（直接经济损失占灾区国民收入的比例），并对绝对和相对评估结果的等级进行了划分；最后，建立了绝对评估和相对评估结果对比的灾情综合评估模式。经过实例应用验证，评估结果能较好地反映灾情。     

A versatile and effective trap for detecting and monitoring stored-product coleoptera

An efficient multi-species trap of corrugated paper and utilizing plastic pitfall devices containing a vegetable-oil based food attractant, was developed for the purpose of detecting and monitoring stored-product insects. Adults of Oryzaephilus surinamensis (L.), Tribolium confusum Jacquelin duVal and larvae of Trogoderma variabile Ballion were trapped successfully in laboratory assays.Using a multiple-choice olfactometer, Tribolium confusum and Tribolium castaneum (Herbst) adults were shown to respond to 4,R-8,R-dimethyldecanal, their natural aggregation pheromone, and to distinguish between this and other diastereomers when tested simultaneously. The S-R and S-S diastereomers may be slightly inhibitory to T. castaneum response. Tribolium confusum was attracted to racemic 4, 8-dimethyldecanal applied to rubber septa lures. High doses of the pheromone reduced attraction. The pheromone is currently being used with food attractants in the trap for monitoring field populations of Tribolium and other stored-product insects.     

海外耕地保护的社会化扶持对策及其启示

由于耕地为公众提供了大量的、具有强烈外部性的非生产性功能,很多国家都把耕地保护作为一个公共目标,并通过社会化扶持手段来得到实施.中国作为一个人多地少,人均耕地占有量低的国家,耕地保护任务更加突出,虽然"切实保护耕地"成为我国的一个基本国策,提出要执行"世界上最严格的耕地保护",并制定了耕地总量动态平衡、土地用途管制等一系列耕地保护政策,但耕地保护整体效果却不窖乐观,其中一个原因就是没有形成全社会共同保护耕地的氛围.本文对当今世界耕地保护社会化扶持的政策依据及实践手段进行综合与分析,并结合我国耕地保护的形势,提出了我国耕地保护社会化扶持的一系列对策措施,包括加快耕地产权制度建设,明确耕地保护的责任主体;重视耕地的非生产功能,提高全社会的耕地保护意识;采用综合优惠措施,激励农户的耕地保护行为;完善城镇发展规划,严格控制城镇对耕地的侵占;延长农产晶产业链,增加农业产业的经济收入.     

Long-Term Effects of Changing Land Use Practices on Surface Water Quality in a Coastal River and Lagoonal Estuary

The watershed of the Neuse River, a major tributary of the largest lagoonal estuary on the U.S. mainland, has sustained rapid growth of human and swine populations. This study integrated a decade of available land cover and water quality data to examine relationships between land use changes and surface water quality. Geographic Information Systems (GIS) analysis was used to characterize 26 subbasins throughout the watershed for changes in land use during 1992–2001, considering urban, agricultural (cropland, animal as pasture, and densities of confined animal feed operations [CAFOs]), forested, grassland, and wetland categories and numbers of wastewater treatment plants (WWTPs). GIS was also used together with longitudinal regression analysis to identify specific land use characteristics that influenced surface water quality. Total phosphorus concentrations were significantly higher during summer in subbasins with high densities of WWTPs and CAFOs. Nitrate was significantly higher during winter in subbasins with high numbers of WWTPs, and organic nitrogen was higher in subbasins with higher agricultural coverage, especially with high coverage of pastures fertilized with animal manure. Ammonium concentrations were elevated after high precipitation. Overall, wastewater discharges in the upper, increasingly urbanized Neuse basin and intensive swine agriculture in the lower basin have been the highest contributors of nitrogen and phosphorus to receiving surface waters. Although nonpoint sources have been emphasized in the eutrophication of rivers and estuaries such as the Neuse, point sources continue to be major nutrient contributors in watersheds sustaining increasing human population growth. The described correlation and regression analyses represent a rapid, reliable method to relate land use patterns to water quality, and they can be adapted to watersheds in any region.     

汕头红树林湿地表层沉积物环境因子对PAHs分布的影响

为了探明红树林湿地表层沉积物环境因子对多环芳烃分布的影响,野外采集了汕头红树林湿地表层沉积物样品,实验室内有机溶剂提取、氧化铝硅胶柱净化和气质联用分析了沉积物多环芳烃的质量分数、CHN元素仪分析了沉积物有机碳和黑碳的质量分数、激光粒度仪分析了沉积物的粒级组成,研究了沉积物有机碳、黑碳和粒度等各环境因子与多环芳烃的相关性.结果表明:有机碳与2～3环、4环和总多环芳烃的质量分数显著相关(P<0.05),表明表层沉积物有机碳的质量分数对PAHs的分布产生了显著的影响;黑碳与2～3环、4环、5～6环和总多环芳烃的质量分数显著相关(P<0.01),表明表层沉积物黑碳的质量分数对PAHs的分布产生了显著的影响;粘粒与2～3环多环芳烃的质量分数显著相关(P<0.05),与4环、5～6环和总多环芳烃的质量分数显著相关(P<0.01),表明表层沉积物粘粒的质量分数对PAHs的分布也产生了显著的影响;多元线性逐步回归分析显示,各回归方程黑碳的偏回归系数值都是最大,沉积物黑碳的质量分数对多环芳烃的质量分数贡献最大,表明黑碳是多环芳烃分布的主要影响因素.