化工厂排放SO2对周围植物的影响

对某厂区及常年盛行风下风向地区植物受ＳＯ２危害情况进行了调查，并测定了部分植物叶片中的硫含量。从植物叶片中的硫含量可间接地判断大气被ＳＯ２污染的程度及植物对ＳＯ２吸收与抵抗能力的强弱。     

FRESH GROUND WATER STORED IN AQUIFERS UNDER THE CONTINENTAL SHELF: IMPLICATIONS FROM A DEEP TEST,NANTUCKET ISLAND,MASSACHUSETTS1

ABSTRACT: A deep water-resource and stratigraphic test well near the center of Nantucket Island, about 40 miles (64 km) off the New England Coast, has encountered freshwater at greater depth than predicted by the Ghyben-Herzberg principle. An uppermost lens of fresh-water, which occupies relatively permeable glacial-outwash sand and gravel to a depth of 520 ft. (158 m), is probably in hydrodynamic equilibrium with the present level of the sea and the height of the water table. However, two zones of freshwater between 730-820 ft. (222-250 m) and 900-930 ft. (274-283 m) are anomalously deep. A third zone extending from 1150-1500 ft. (350-457 m) contains slightly salty ground water (2 to 3 parts per thousand dissolved solids). Several explanations are possible, but the most likely is that large areas of the Continental Shelf were exposed to recharge by precipitation during long periods of low sea level in Pleistocene time. After the last retreat of glacial ice, seawater rapidly drowned the shelf around Nantucket Island. Since then, about 8000 years ago, the deep freshwater zones which underlie dense clay layers have not had time to adjust to a new equilibrium. Under similar circumstances freshwater may remain trapped under extensive areas of the Continental Shelf wherever clay confining beds have not permitted saltwater to intrude rapidly to new positions of hydrodynamic equilibrium. The implications are far reaching because all continental shelfs were exposed to similar hydrologic influences during Pleistocene time.     

Comparison of the Vegetation and Seed Bank on Hedge Banks of Different Ages in Brittany,France

The composition of the herbaceous cover and the seed bank of old and recent hedge banks in Brittany were studied and compared. Concentration method was used for seed bank samples. Grimes plant strategies were used to explain observed patterns. The analysis of the seed bank of these hedge banks showed that the species richness and diversity differed in relation to the date of construction of the hedge banks. The seed banks of recent hedge banks were richer and more diversified than those of old hedge banks. Differences in the floristic composition of the established plant cover between the recent and old hedge banks were determined by multivariate analyses. The species exclusively found in the seed bank and in the herb cover of recent hedge banks were mainly grassland species, whereas the species that only occurred on old hedge banks tended to be woodland species. The floristic composition of the two compartments (established vegetation and seed bank) was very different. A multivariate analysis revealed that the difference between the composition of the seed banks of recent and old hedge banks was less than that between the composition of the established vegetation and seed bank of hedge banks of the same age. Both seed bank and vegetation of recent hedge banks were dominated by ruderal species, whereas old hedge vegetation was dominated by stress-tolerant woodland species, indicating that mechanically constructed hedge banks may impose limitations on colonization by late woodland species.     

九十年代以来全球重大天气气候事件回顾

本文首先揭示了九十年代全球变暖背景下北半球中高纬度地区冬季的异常冷暖气候事件及其相应的环流形势。着重回顾了全球热浪、暴雨洪涝、大范围持续干旱及热带风暴等重大灾害性天气气候事件及其影响，并对其形成的可能原因进行了一些诊断分析。     

RESISTANCE TO FLOW OVER RIPRAP IN STEEP CHANNELS1

ABSTRACT: A series of flume tests were conducted to determine the flow resistance of angular shaped riprap in steep channels. Flow resistance was expressed in terms of the Darcy-Weisbach friction factor and the Manning's roughness coefficient. Prototype channels of 4 ft. (1.2 m) and 12 ft. (3.7 m) in width were constructed at slopes ranging from 0.01 to 0.20. The channel beds were comprised of angular riprap of median diameters of 1, 2, 4, 5, and 6 inches (2.59, 5.59, 10.41, 12.95, and 15.75 cms). The Darcy-Weisbach and Manning's coefficients were determined for each test condition prior to bed failure. The resulting Darcy-Weisbach coefficients were related to the channel energy gradient and the bed relative submergence for highly turbulent flow. Also, Manning's roughness coefficients were related to the product of the median stone diameter and energy gradient. Because of the angular shape of the riprap and the wedging and/or packing of the bed materials, the resistance to flow was found to exceed the flow resistance values predicted by previous studies. Expressions were presented for estimating the resistance to flow for angular riprap in steep channels.     

厨房空气中甲醛卫生标准的研究

通过对甲醛嗅及刺激阈的测试，毒理学资料分析，结合现场流行病学调查，提出了厨房空气中甲醛的一次最高容浓度为０．１３ｍｇ／ｍ＾３。     

城市新增大气污染源合理布局判据的研究

试图提出了一种以环境损失作为评价污染源布局判据的观点，给出了大气环境损失系数的计算方法及污染源合理布局优化计算模型，并结合实例作了进一步的分析。     

颗粒态重金属通过河流与大气向海洋输送

本文综述了河流与大气向海洋输送颗态重金属的过程、特点及输送通量、参考文献８３篇。     

机动车尾气的产生及对人群健康的影响和防治对策

较详细的介绍了机动车燃料和尾气的关系，全面论述了尾气中主要污染物对人体健康的危害，并对防治尾气的污染提出了建议。     

略论公民环境权人类社会全体成员享有在健康、安全和舒适的环境中生活的权利

论述了公民环境权的产生、性质及内容。分析了公民环境权与可持续发展的关系及我国公民环境权的现状。