Comparative analysis of small mammal communities in Chisinau and Yaroslavl, two European cities located in different biomes

Comparative analysis of the structure of small mammal communities has been performed in two European cities located in different biomes: Chisinau (2008?C2009) and Yaroslavl (1994?C2002). The parameters studied included abundance, species composition, similarity and difference of faunas, species diversity, and proportions of groups differing in predisposition to synanthropy. It has been found that the structure of small mammal communities in these cities depends on specific physiographic conditions of the surrounding areas and on the distinctive features of the cities themselves (their structure, age, etc.). The similarity between the faunas is accounted for by the common ecological patterns of fauna formation in the biota of urban cenoses.     

Effect of anthropogenic pollution on oxidative processes in the liver of fish from the Rybinsk Reservoir

The levels of total lipids, peroxidation products, and antioxidant activity in the liver were studied in fish species living in unequally polluted areas of the Rybinsk Reservoir and differing in their ecology and taxonomic position: the bream (Abramis brama L.), roach (Rutilus rutilus L.), burbot (Lota lota L.), and zander (Stizostedion lucioperca L.). The fish from polluted water areas were characterized by higher levels of total lipids and malonic dialdehyde and a deficiency of antioxidants. It is shown that the test parameters depend on the type of feeding and mode of life of the fish species.     

基于地貌指数的汶川地震灾区单沟泥石流总量计算方法

现行的泥石流总量计算方法普遍存在计算参数较难获取或难以精确获取的问题,加上汶川地震灾区沟谷内分布大量的由崩塌、滑坡体等形成的固体松散物质;所以多数泥石流总量计算公式在汶川震区存在局限性.参考适用于以崩塌、滑坡体为主要物源的泥石流总量计算公式;分析研究区范围内地形地貌发育状态与降雨因素及其地质条件之间的影响关系;将地貌指数(Strahler积分)应用于泥石流总量计算,尝试解决缺乏降雨数据情况下泥石流总量计算问题.根据“8.13”四川清平群发性泥石流数据初步回归分析得到适合于汶川震区的泥石流总量计算模型.     

Some Effects of Atmospheric Fluoride on Plant Metabolism

Leaves of Tendergreen bean plants exposed to atmospheric fluoride concentrations in the range 1.7 to 7.6 μg/m³ showed increased levels of enolase and catalase activity and decreased levels of pyruvate and α-ketoglutarate. Phosphoenolpyruvate carboxylase activity and oxalacetate were not affected. The leaves of Milo maize plants exposed to 5.0 μg F/m³ showed increased levels of enolase and pyruvate kinase activity and a decreased level of pyruvate. Oxalacetate and α-ketoglutarate levels were not affected. Catalase activity was increased, then decreased by IIF fumigation. The changes induced by HF were greatest six to 10 days after the start of fumigation and disappeared or decreased in magnitude during the post-fumigation period.     

Review of Recent Studies of Sulfur Oxides as Air Pollutants

The current literature on the role of sulfur dioxide in air pollution     

The Effect of Nucleating Particulates on Photochemical Aerosol Formation

The role of nucleating particulates in the formation of photochemical aerosols has been studied in a steady, laminar flow of ultrafiltered air containing NO₂ and octene-1 in the concentration range of (30 to 170 ppm) when subjected to intense irradiation under isothermal conditions. The particulates consisted of monodisperse polystyrene latex (d = 0.36 μ.) in concentrations similar to those in the atmosphere (6 × 10¹ to 3 × 10³ cm^–3); the irradiation intensity varied between (6 to 40 × 10³ lumen/liter) and the mean exposure duration between 30 and 180 sec. Samples of the flow prior to and after its photoactivation were withdrawn either by an Aerosol Spectrometer (AS) or by a Royco Aerosol Photometer (PH). While these indications refer thus to the same system, they differ, because the photometric data include all colloidal components in the airborne state, whereas the counts obtained from the AS deposits refer only to the nucleated latex particles. The following pattern becomes evident: The photochemical reaction yields fractional products (less than three percent) which have the tendency to agglomerate (or polymerize) due to their relatively low volatility—independent of the presence or absence of nucleating particulates. In their presence, this reaction becomes kinetically more probable and thus faster, hence the accumulant formation occurs preferably on the nuclei and causes their growth such that, e.g., a 10-fold higher nuclei concentration will produce under the same conditions 10 times the accumulant mass while autonucleation is suppressed. The growth process appears thus principally different from that of fog formation by H₂O-condensation, whereas for identical super saturation it is inversely proportional to the nuclear concentration. In the absence of nuclei autonucleation, i.e., self-agglomeration, occurs at a much lesser reaction rate and higher photon demand. The growth rate of the nuclei, when present, depends on the concentration of the oxidation catalyst (NO₂), its interaction with the nuclei surface is indicated. Under identical conditions the mass of nuclear accumulant is directly proportional to the concentration of the reactive hydrocarbon, while the growth rate depends on the light intensity and the exposure duration. The findings indicate that density and nature of particulate matter present in an air mass prior or during photo-activation are—aside from the chemical reactant levels—of major significance in aerosol formation.     

Apparent Photosynthesis as a Measure of Air Pollution Damage

A system has been developed to automatically measure the effects of air pollutants in the ambient air on the rate of CO₂ exchange by intact leaves of citrus trees growing in the field. A miniaturized system utilizing the same nondispersive infrared CO₂ analyzer has been designed to study individually the effects of different concentrations of air pollutants on photosynthesis and respiration by plants.     

Polynuclear Aromatic Hydrocarbons Associated with Particulates in Pittsburgh Air

Pittsburgh air was sampled continuously at one site for 886 hrs./sample at 45 cfm with a high volume sampler equipped with a horizontal elutriator as a first stage of separation, and an MSA 1106B glass fiber filter as a final particulate collection stage. The horizontal elutriator was designed to simulate the particulate deposition characteristics of the human respiratory tract. Samples were collected during the period June 1964 to February 1965. Respirable and non-respirable particulate samples were analyzed for polynuclear aromatic hydrocarbon content by a new technique which utilized dual column, flame ionization gas chromatography. It was possible to quantitatively analyze a concentrated benzene extract of the particulate sample for the following individual components: 1, 2 benzanthracene; chrysene; pyrene; 3,4 benzofloranthene; 1, 12 benzoperylene. It was not possible to distinguish between 3,4 benzopyrene, 1,2 benzopyrene and perylene; only the total quantity of these compounds present was detected. This analytical technique is comparable in sensitivity to formerly reported, more time-consuming methods and is very rapid, requiring less than one hour to perform after benzene extraction. Amounts of the above compounds associated with the two particulate fractions collected are reported and discussed.