Land cover types and ecological conditions of the Estonian coast

Detailed analysis of the land cover of the Estonian coastal zone is presented based on Estonian laws on coastal zone management, the CORINE Land Cover (CLC) system, the status of protected areas, and administrative division data of Estonia. By law the coastal zone is defined as a 200-m wide zone landward from the mean sea level line. The length of the Estonian coastline (including the islands) is 3794 km. The 200-m zone of the Estonian coast is very diverse. Out of the 34 CORINE land cover types represented in Estonia 30 are found in the coastal zone. Three dominating land cover types in the coastal zone of Estonia are inland marshes, coniferous forest and semi-natural grassland. Their total share is 47%; the other 27 land cover types represented here cover 53% of the coastal zone. The Estonian coastal zone is generally in a good natural condition. The proportion of artificial surfaces throughout the zone is merely 4.7%, while agricultural landscapes cover only ca. 10%. Land cover data for the coastal zone are also presented by county. Of the 200-m coastal zone 24% is under protection, which is more than twice the value for Estonia as a whole (11%). Legislative protection of the coastal zone is presently satisfactory. The use of the CORINE Land Cover system enables comparisons with other European regions since CLC data have been compiled for most of Europe.     

Chemical transformation and flux of different forms of arsenic in the carb Carcinusmaenas

The amount of ingested arsenic assimilated and eliminated by the crab appeared to depend on chemical form of arsenic present in the food. Arsenic-74 was translocated rapidly with a high percentage located in hepatopancreas and exoskeleton. The speciation of radioarsenic determined by sequential extraction of experimental food, feces, muscle and hepatopancreas showed that there is no efficient mechanism within the crab which can covert lipid and water soluble arsenic to arsenite and residual arsenic or vice-versa. The biological mechanism in crab selectively and effectively excretes soluble form of arsenite and residual arsenic much more readily than organic arsenic.     

Estimation of critical submergence for an intake in a stratified fluid media by neuro-fuzzy approach

Most of the large surface reservoirs are stably stratified throughout most or all of the year. One means of assisting in the management is to allow for the selective withdrawal from the reservoir. The value of the intake’s submergence when the upper layer fluids begin to be drawn into the intake is known as “critical submergence”. In this study, the critical submergence for a circular intake pipe in a stratified body is investigated. Experiments were conducted on a vertically flowing downward intake pipe in a still-water reservoir. Experimental results are compared with that of the neuro-fuzzy models.     

Residual Cadmium and Lead Pollution at a Former Soviet Military Airfield in Tartu, Estonia

This paper presents data on the levels and dynamics of cadmium (Cd) and lead (Pb) concentration in the plants, soil, and groundwater of the landing corridor and airfield of a former Soviet military air base in Estonia, immediately at the end of its 40-year service in 1992 and over the following 8 yr. In 1991–92 we found high Cd concentrations in the meadow plants Trifolium pratense and Dactylis glomerata (up to 56 mg kg^-1). In 1993, the Cd concentration had dropped to 0.12–0.19 mg kg^-1, and stabilized in 1997–2000 at 0.04 mg kg^-1. Cd concentration in plants decreased significantly with increasing distance from the landing strip. Elevated Cd concentration (0.012 mg L^-1) was found in the fuel of the TU-22M (Backfire) strategic bombers. In 1991 and 1993, leaded fuel influenced the mean Pb concentration in plants (1.8–4.2 mg kg^-1). Average Pb concentration in both topsoil and the 30–40 cm soil horizon decreased between 1991 and 2000 from 28 to 6.5 and from 13.5 to 4.3 mg kg^-1, respectively. Cd concentration in the topsoil of the landingcorridor showed a significant increase between 1991 and 1993 (0.07–0.3 and 0.3–1.2 mg kg^-1, respectively), but stabilized later on the level of 0.04 mg kg^-1. The concentrations of both Pb and Cd in the soil were higher closer to the fuel bunkers. Current assessment of the movement of these metals from the vegetation to the soil and to groundwater is linked to potential leaching to the surrounding environment.     

Prenatal diagnosis of a fetus with pure partial trisomy 1q32-44 due to a familial balanced rearrangement

We diagnosed a pure partial trisomy of the long arm of chromosome 1 in a fetus with multiple malformations detected prenatally. The father was a carrier of a balanced rearrangement involving 46,XY,inv(1)(qter→p36::q32→qter::p36→q32). The fetus had preaxial polydactyly, low-set ears, macrocephaly, a prominent forehead, a broad and flat nasal bridge, a small mouth, an arched palate, micrognathia and unilateral renal agenesis. The couple had previously an infant with the same phenotypic abnormalities. The aberration was initially detected on amniocentesis with GTG banding and was confirmed by fluorescence in situ hybridization (FISH). Our case and other published pure trisomy 1q32-44 cases showed similarities, which allowed the further delineation of the trisomy 1q syndrome. Copyright © 2002 John Wiley & Sons, Ltd.     

An assessment of metal contamination in the shelf sediments at the southern exit of Bosphorus Strait,Turkey

Concentrations and areal distribution of Al, As, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, V, and Zn were determined in the surficial sea bottom sediments along the coastal areas of Istanbul at the southern exit of the Bosphorus Strait, ?stanbul, Turkey. The pollution status of shelf sediments was evaluated by employing pollution indicators (enrichment factors, geo-accumulation, and ecological risk indexes) and sediment quality guidelines (threshold effect level/probable effect level, effect range median (ERM)/effect range low). The results demonstrated that Cd, Cr, Zn, Cu, and Pb were enriched minor to moderate. The net sediment transport patterns show terrestrial inputs in front of the short streams. Another polluted region is at the western margin of the southern Bosphorus exit, where sediment transport is mainly controlled by the secondary currents driven by the Bosphorus jet, and depending on a sand ridge extending offshore. Based on the sediment quality guidelines, Cu, Pb, As, and Cr were likely the most dangerous chemicals to pose environmental risk, and may show toxic biological results. The areal distribution of ecotoxicological index (m-ERM-Q) suggested that 20% of the sediment sample sites fall in the medium–high priority zone and scattered at some specific areas along the coast.     

Primary Productivity in the Golden Horn

The shores of the Golden Horn—once most important seaport of the region—represented throughout history a romantic and recreational venue. This tributary to the Bosphorus, however, became seriously polluted with the extensive industrialization and rapid population growth in Istanbul over the past century. Two main tributaries, the Alibeykoy and the Kagithane, dumped both liquid and solid waste from residential areas and industry (small and large-scale) into the Golden Horn. As a result of this pollution, the landward three to four kilometers of the estuary became swamped with sediment. The dominance of anaerobic activity resulted in a highly unpleasant smell, and the shallow depth as one progressed up the bay restricted navigation. In early 1997 The Istanbul Metropolitan Municipality began a dredging operation and gradually diverted all domestic and industrial wastewater discharge from the Golden Horn. Since then there have been remarkable improvements in water quality. This paper presents the state of eutrophication through the water body of the Golden Horn; parameters such as DO, TKN, NH₃-N, NO₃-N, the total phosphorus (TP) and dissolved phosphorus (PO₄-P), phytoplankton and chlorophyll-a have been were analyzed in samples of water taken from various points in the Golden Horn. The presence of DO and the phytoplankton, both indicators of primary productivity in an aquatic body, has been evaluated in relation to former conditions.     

Designing a conservation reserve network with minimal fragmentation: A linear integer programming approach

In the biological conservation literature, the optimum reserve site selection problem has often been addressed by using the prototype set covering and maximal covering formulations, assuming that representation of species is the only criterion in site selection. This approach usually results in a small but highly fragmented reserve, which is not useful for practical conservation planning. To improve the chances of species' persistence, it may be desirable to reduce habitat fragmentation. This paper presents a linear integer programming formulation to minimize spatial gaps between selected sites in a reserve network, which is applied to a data set on breeding birds. The authors express their willingness to share the database used in this study. Those readers who wish to have access to the data may contact Robert A. Briers at r.briers@napier.ac.uk.     

近10年来三峡消落带土壤氮、磷时空分布特征研究

消落带是位于水陆交错带的一种特殊生态系统.消落带土壤作为生态系统中氮、磷元素重要的“源”与“汇”,在生物地球化学循环研究中具有重要意义.该研究基于中国知网CNKI以及Web of Science数据库检索近10年三峡消落带土壤氮、磷研究文献,提取w（TN）、w（TP）数据并进行统计,从宏观尺度上分析w（TN）、w（TP）的时空分布特征.结果表明:①高程分布上,当高程高于155 m时,土壤w（TN）（0.75~1.17 g/kg）随着高程增加呈下降趋势,土壤w（TP）未发生显著变化（0.53~0.60 g/kg）;当高程低于155 m时,土壤w（TN）处于较低水平（0.66~0.86 g/kg）,但w（TP）维持较高水平（0.60~0.76 g/kg）.②时间分布上,消落带土壤w（TN）整体呈现逐年递减的趋势,Pearson相关系数为-0.64,但是w（TP）没有显著变化.③地区分布上,三峡上游库区消落带土壤w（TP）出现显著高值,下游库区w（TN）出现显著高值.研究显示:不同高程土壤受植物残体分解等因素影响,在落干期w（TN）上升,在浸没期向上覆水体释放TN;水位调节导致的淹没强度变化对消落带土壤中TN产生淋溶作用,而对TP的影响较小;对于消落带上游地区应更关注土壤中高w（TP）带来的环境风险,而对于消落带下游地区应更关注因水土流失和非点源输出导致的高w（TN）所致环境风险.      

Dimethoate-induced oxidative stress and DNA damage in Oncorhynchus mykiss

The present study was conducted in order to investigate pro-oxidant activity of dimethoate in liver and brain tissues following sublethal pesticide exposure for 5, 15 and 30 d by using SOD, GPx, CAT enzyme activities and lipid peroxidation as biomarkers as well as DNA damaging potential via detecting% Tail DNA, Tail moment and Olive tail moment as endpoints in erythrocytes of Oncorhynchus mykiss in an in vitro experiment. Antioxidant enzyme activities were found to elicit two staged response which was an initial induction followed by a sharp inhibition in liver tissue while a sustained increase in GPx activity and slight stimulation in SOD activity were detected in brain tissue. Lipid peroxidation showed an ascending pattern throughout the exposure period in both tissues and a decreasing trend was determined in tissue protein levels which was proved to be positively correlated with duration. Similar findings were obtained from outcomes preferred to quantify DNA damage and TM was decided to reflect the extent of damage more sensitively because of determined positive correlation with concentrations applied. Considering these results, it can be concluded that oxidative stress condition evoked by dimethoate could not be responded effectively and genotoxic nature of pesticide was proven by determined clastogenic effect possibly via being an alkylation agent or stimulating the production of reactive species.