Worker policing and nest mate recognition in the ant <Emphasis Type="Italic">Formica fusca</Emphasis>

A conflict over male production arises in social insects where workers are able to lay unfertilized male eggs. This happens because each female (queen or worker) is most closely related to her own sons and is thus predicted to reproduce. The conflict is modulated by worker policing where workers prevent each other from reproducing by aggression or egg cannibalism. In this study, we show that in the ant Formica fusca, worker policing occurs by egg cannibalism rather than by overt aggression among workers. Furthermore, we show that, contrary to bees, wasps and other ant species, egg discrimination in F. fusca is not based only on a universal queen signature chemical and that nest mate recognition of eggs occurs.     

A baseline study on the concentrations of chlordane-, PCB-and DDT-compounds in Finnish fish samples in the year 1982

113 Fishes (pike, vendace and roach) samples were analyzed for chlordane, PCB-and DDT-compounds. The average concentrations in pike ($\text{Esox lucius}$) muscle tissue in Finnish lakes were 0.05, 0.01 and 0.01 mg/kg wet weight for PCB compounds, total DDT and chlordanes respectively. The results show that chlordanes are evenly distributed in the Finnish environment which indicate that the main part of chlordanes in Finnish fish is due to long range transportation.     

GC-profiles of chlorinated terpenes (Toxaphenes) in some Finnish environmental samples

The profiles of chlorinated terpenes in Finnish environmental samples were compared by GLC-SIM technique with those of toxaphene and Eastern European “dark”. The profiles in the seal blubber in the Northern and in the Eastern Baltic Sea proved to be similar. Chlorinated terpenes were found to be present in Finnish human milk.The spent bleach liquor of pine kraft pulp mill contained components having similar retention times and responses to those from toxaphene components.     

Biodiversity, distributions and adaptations of Arctic species in the context of environmental change

The individual of a species is the basic unit which responds to climate and UV-B changes, and it responds over a wide range of time scales. The diversity of animal, plant and microbial species appears to be low in the Arctic, and decreases from the boreal forests to the polar deserts of the extreme North but primitive species are particularly abundant. This latitudinal decline is associated with an increase in super-dominant species that occupy a wide range of habitats. Climate warming is expected to reduce the abundance and restrict the ranges of such species and to affect species at their northern range boundaries more than in the South: some Arctic animal and plant specialists could face extinction. Species most likely to expand into tundra are boreal species that currently exist as outlier populations in the Arctic. Many plant species have characteristics that allow them to survive short snow-free growing seasons, low solar angles, permafrost and low soil temperatures, low nutrient availability and physical disturbance. Many of these characteristics are likely to limit species' responses to climate warming, but mainly because of poor competitive ability compared with potential immigrant species. Terrestrial Arctic animals possess many adaptations that enable them to persist under a wide range of temperatures in the Arctic. Many escape unfavorable weather and resource shortage by winter dormancy or by migration. The biotic environment of Arctic animal species is relatively simple with few enemies, competitors, diseases, parasites and available food resources. Terrestrial Arctic animals are likely to be most vulnerable to warmer and drier summers, climatic changes that interfere with migration routes and staging areas, altered snow conditions and freeze-thaw cycles in winter, climate-induced disruption of the seasonal timing of reproduction and development, and influx of new competitors, predators, parasites and diseases. Arctic microorganisms are also well adapted to the Arctic's climate: some can metabolize at temperatures down to -39 degrees C. Cyanobacteria and algae have a wide range of adaptive strategies that allow them to avoid, or at least minimize UV injury. Microorganisms can tolerate most environmental conditions and they have short generation times which can facilitate rapid adaptation to new environments. In contrast, Arctic plant and animal species are very likely to change their distributions rather than evolve significantly in response to warming.     

环境变化背景下北极生物的多样性、分布及其适应性

生物个体是对气候变化和紫外线B(UV－B)辐射变化产生反应的基础,而且这种反应会在各种时间尺度上发生.北极地区的动物、植物以及微生物种类的多样性从表面上看是低的,而且从北方针叶林到极地荒漠逐渐减少,但其原始物种却很丰富.与这种物种多样性随纬向梯度减少的趋势相反,一些空间分布范围很广的单一优势物种的优势度则呈增长趋势.全球气候变暖可能会减少该地区的物种多样性,并限制到这些物种的分布范围,尤其是在该地区生物分布的北部边缘,一些极地特有的动物和植物种类会面临着灭绝的危险.最有可能侵入苔原地带的物种是那些目前生存在极地外缘的北方地区生物.许多植物都具有自身的特征使它们能够在以下环境中生存短暂的无冰雪覆盖的生长季节,低的太阳高度角,永久冻结地带及低的土壤温度,贫乏的养分获取条件以及极少的物理扰动.以上这些特征有些可能会限制当地物种对气候变暖的反应,但其最主要的因素是这些物种与那些潜在的入侵物种相比缺乏竞争能力.北极地区陆生动物拥有许多适应特性,这使它们能够适应北极地区剧烈的温度变化.许多动物通过冬眠或迁移来逃避极地地区的恶劣天气和资源短缺.北极地区动物生存的生物环境则相对简单几乎没有天敌、竞争者、疾病、寄生生物,但同时食物资源也很短缺.极地陆生动物可能对由气候变化带来的温暖而干旱的夏季非常不适应,这种变化将会影响到动物的迁移路线、途中栖息地,并会改变冬季积雪的状况和冻融的循环过程.气候变化还会改变动物繁殖和发育的季节,并会引来新的竞争者、捕食者、寄生生物以及疾病等.极地微生物也能很好地适应该地区的气候一些微生物甚至在-39℃的低温下还能进行代谢活动.蓝藻细菌和藻类生物有着很广泛的适应策略,这能够使它们避免(至少可以减少)紫外线的伤害.微生物能够忍受许多环境条件,而且其生长周期很短,这些特点将使它们能很快适应新的生存环境.与此形成对比的是,极地植物和动物很可能通过改变其分布范围而不是积极的生物进化来适应环境的变暖.     

Nonparasitic Nematoda provide evidence for a linear response of functionally important soil biota to increasing livestock density

Soil acidity, nutrient availability and livestock density have a major influence on the belowground ecological community. As fast decomposition rates are due mostly to bacterial-based pathways and slower decomposition rates mostly to fungal-based pathways, it is helpful to condense empirical information in the so-called Nematode Channel Ratio (NCR). The NCR is shown to be a good indicator of efficiency in soil decomposition processes. We argue that in intensive agroecosystems, other fungivore members of the decomposer food web may outcompete the hyphal-feeding nematodes. We demonstrate how the NCR can be used to set ecological standards for sustainable use of the soil in agroecosystems. To summarize the interactions between the microbial resources and the decomposer nematofauna according to increasing land management, we propose the use of the fifth percentile as proxy for a sustainable environmental quality of grasslands on sandy soils, and the NCR mean as the upper threshold for low-stocked farms.     

The Effect of Traction Sanding on Urban Suspended Particles in Finland

Springtime urban road dust forms one of the most serious problems regarding air pollution in Finland. The composition and origin of springtime dust was studied in southern Finland with two different methods. Suspended particles (PM10 and TSP) were collected with high volume particle samplers and particle deposition was collected with moss bags. The composition of the PM(1.5-10) fraction was studied using individual particle analysis with SEM/EDX. The deposition in the moss bags was analysed with ICP-MS. The results showed that during the study period, approximately 10% of both PM(1.5-10) particles and the deposition originated from sanding. Other sources in the springtime PM(1.5-10) were e.g. asphalt aggregate or soil and combustion processes. It can be concluded that sanding produced a relatively small amount of particulate matter under the investigated circumstances.     

Impact of unleaded gasoline introduction on the concentration of lead in the air of Dhaka, Bangladesh

Airborne particulate matter (APM) samples collected at a semiresidential area in Dhaka, Bangladesh, during the periods of 1994 and 1997-2000 have been studied to assess the impact of the use of unleaded gasoline in Bangladesh. According to scanning electron microscopy/ energy-dispersive X-ray microanalyzer studies, lead (Pb) was found as Pb sulfates and Pb halides in motor-vehicle exhaust particles, whose diameters were some hundreds of nanometers. No significant changes in the annual averages of APM mass and black carbon concentrations have been observed over the period. The yearly average Pb concentration reached a maximum value of 370 ng/m3 in the particulate matter with an aerodynamic diameter < 2.5 microm fraction in 1998. In 2000, the concentration decreased to approximately one-third (106 ng/m3) of the high earlier values after the introduction of unleaded gasoline in 1999. A significant lowering of the blood Pb level of the population over next few years is expected as a result of this great decrease in Pb concentration.