Chemical Composition Of Surface Water Research Articles

Toxic Element Contamination Sources in the Surface and Groundwater of the Elbrus Region: Geochemistry and Health Risks

The region surrounding the Elbrus volcano in the Great Caucasus is a popular tourist destination, home to native people and an area of the richest ore mineral resources. Based on the chemical composition of surface water, mineral, and groundwater in the Elbrus area, as well as statistical and thermodynamic calculations, waters with high concentrations of Mn, Cu, Zn, Mo, Ba, W, Pb, and As were identified, possible mineral phases that may lead to these metal concentrations in water were estimated, and risks to human health were assessed. Two main sources of surface water pollution have been identified: (1) water from tailings that are enriched due to oxidation of sulfide minerals is considered a source of As (181 µg/L) and Mo (2070 µg/L) pollution in the area of the Tyrnyauz W-Mo deposit; and (2) CO2-rich waters of deep horizons discharge on the earth surface with high concentrations of As (828 µg/L) and W (504 µg/L). It has been shown that compared to all toxic elements studied, only Mo and As have adverse non-carcinogenic effects on adult health. The estimated carcinogenic risk of As in the mine area was 1.7 × 10−3 and exceeded the generally accepted range of 10−4 to 10−6. In order to minimize the health risks, regular monitoring of water quality is required when mining activities on the Tyrnyauz W-Mo deposit are renewed.

Hydrochemical Characteristics and Control Factors of Surface Water in Kuaize River Basin at the Upper Pearl River

The Kuaize River is a small typical karst watershed in the source area of the Pearl River as well as an important coal mining area in Eastern Yunnan with a fragile ecological environment. Strengthening the research on the water environment in the region plays an important role in supporting the comprehensive management of the ecological environment and water resources in the source region of the Pearl River. Through the systematic collection of surface water, karst groundwater, and mine water samples, mathematical statistics analysis, correlation analysis, ion ratio analysis, absolute principal component scores multiple linear regression(APCS-MLR), and other methods were used to study the characteristics of hydrochemical evolution and control factors in Kuaize River Basin. The results showed that the average pH value of surface water in Kuaize River Basin was 7.8, which was weakly alkaline. The main cations were Ca2+ and Na+, showing the characteristics of Ca2+>Na+>Mg2+>K+. The main anions were HCO3- and SO42-, showing the characteristics of HCO3->SO42->NO3->Cl-. The variation coefficients of Na+, SO42-, and NO3- in surface water were high, showing strong spatial variability. The water chemical type of the trunk stream was mainly HCO3-Ca, whereas the water chemical type of the tributary was relatively complex, mainly HCO3-Ca, HCO3-Ca·Na, and HCO3·SO4-Ca·Na. The chemical composition of surface water was mainly affected by rock weathering, cation exchange, and human activities. Ca2+, Mg2+, Na+, and HCO3- in surface water mainly came from the weathering of carbonate rock and silicate rock; SO42- mainly came from the oxidation of sulfide, such as pyrite in coal seams; K+, Cl-, and NO3- mainly came from domestic sewage and agricultural activities. The APCS-MLR receptor model analysis results showed that the surface water in the Kuaize River Basin was mainly affected by sulfide oxidation, carbonate weathering, weathering of silicate rock in mine water, domestic sewage, agricultural activities, and unknown sources. In general, the contribution rate of human activities such as mining, domestic sewage, and agricultural activities to the surface water reached 47.17%, indicating that human activities were the key driving factor of surface water chemistry in the Kuaize River Basin.

Douglas-fir plantations impact stream and groundwater chemistry in western Europe: Insights from three case studies in France and Luxembourg

In rural areas, nitrate concentrations in surface waters most often originate from the leaching of excess N fertilizer in agricultural lands, whereas forested catchments often have good water quality. However, Douglas-fir plantations may induce nitrogen cycle unbalances which may lead to an excess of nitrate production in the soil. We hypothesize that the excess of production of nitrate in the soil and nitrate leaching to streamwater is greater in catchments planted with Douglas fir. We used paired catchments in both France and Luxembourg with different land covers (Douglas-fir, Spruce, Deciduous, Grassland and clearcut) which were monitored over a 3–5 year period in order to assess the effect of Douglas-fir plantations on the chemical composition of surface water. Nitrate concentration in the soil and groundwater were also monitored. The results show that nitrate concentrations in streams draining Douglas-fir catchments were two to ten times higher than in streams draining other land covers, but were similar to the clearcut catchment. Nitrate concentrations under Douglas-fir in groundwater (up to 50 mg L−1) and in the soil were also higher than under all other land covers. Soil nitrate concentration was related to stream nitrate concentration. This suggests that soil processes, through excessive nitrate production under Douglas-fir, are driving the nitrate concentration in the stream water and our hypothesis of a transfer of a fairly large proportion of this excessive production from the soil to the stream is supported. This study also shows that nitrate concentrations in surface and ground waters in rural areas could also originate from Douglas fir forested catchments. The impact of Douglas-fir is nevertheless reduced downstream through a dilution effect: mixing tree species at the catchment scale could thus be a solution to mitigate the effect of Douglas-fir on nitrate concentration in surface waters.

Unravelling the occurrence of trace contaminants in surface waters using semi-quantitative suspected non-target screening analyses

Several classes of anthropogenic chemicals such as pesticides and pharmaceuticals are frequently used in human-related life activities and are discharged into the aquatic environment. These compounds can exert an unknown effect on aquatic life and humans if the water is used for human consumption. Thus, unravelling their occurrence in the aquatic system is crucial for the well-being of life and monitoring purposes. To this end, we used nanoflow-liquid and ion-exchange chromatography hyphenated with orbitrap high-resolution tandem mass spectrometry to detect several thousands of features (chemical entities) in surface water. Later, the features were narrowed down to a few focused lists using a stepwise filtering strategy, for which the structural elucidation was made. Accordingly, the chemical structure was confirmed for 83 compounds from different application areas, mainly being pharmaceuticals, pesticides, and other multiple application industrial compounds and xenobiotic degradation products. The compounds with the highest concentration were lamotrigine (27.6 μg/L), valsartan (14.4 μg/L), and ibuprofen (12.7 μg/L). Some compounds such as prosulfocarb, fluopyram, and tris(3-chloropropyl) phosphate were found to be the most abundant and widespread contaminants. Of the 32 sampling sites, nearly half of the sites (47%) contained more than 30 different compounds. Two sampling sites were far more contaminated than other sites based on the estimated concentration and the number of identified contaminants they contained. Our triplicate analysis revealed a low relative standard deviation between replicates, advocating for the added value in analysing more sampling sites instead of sample repetition. Overall, our study elucidated the occurrence of organic contaminants from a variety of sources in the aquatic environment. Furthermore, our findings highlighted the role of suspected non-target screening in exposing a snapshot of the chemical composition of surface water and the localized possible contamination sources.

Hydrogeochemistry Characteristics of Groundwater in the Nandong Karst Water System, China

The hydrogeochemical characteristics of groundwater are an important element in the study of the spatial and temporal variation of groundwater resources, which is crucial to water resources utilization, ecological environmental protection, and human development. Water samples were collected at eight observation of Nandong Karst Water System (NKWS) sites in each month of 2019, and the main ions and isotopes of the water samples were examined. The hydrogeochemistry characteristics of groundwater and its differences with surface water were explored by using the methods of multivariate statistics, Gibbs model. Results showed that the water chemistry types of groundwater were mainly HCO3–Ca and HCO3–Ca·Mg. The analysis of hydrogen and oxygen isotope showed that the initial recharge source of surface water and groundwater were atmospheric precipitation, and the measured hydrogen and oxygen isotopes of surface water were heavier due to the strong evaporation effect. The natural and anthropogenic processes contributed to the chemical composition of surface water and groundwater in the study area. However, the main factor affecting the quality of surface water and groundwater was the input of anthropogenic contaminants. In terms of natural factors, the main chemical ions of surface water and groundwater were mainly controlled by water-rock action originating from weathering and hydrolysis of rocks and soils. Ca2+, Mg2+, and HCO3− mainly originated from natural dissolution of carbonate rocks. K+, Na+, SO42−, and Cl− were partly from atmospheric precipitation. For human activities, Na+ and Cl− were partly from domestic water for local residents. SO42− in surface water mainly came from mining. NO3− in groundwater mainly came from chemical fertilizers, and NO3− in surface water were mainly from human waste and domestic sewage.

The impact of beaver dam removal on the chemical properties of water in drainage ditches in peatland forests

ABSTRACT Despite near-extinction in the nineteenth century, after efficient restoration measures the population of Eurasian beaver (Castor fiber L.) in Latvia currently is viable and growing. While the ecological effect of the species on water quality and biodiversity is generally positive, the high number of animals in production forests often creates challenges for management. Drainage ditches are among the most favoured habitats of beavers resulting in flooded stands, reduced tree growth and economical losses. The aim of the study was to evaluate the chemical properties of water in forest drainage ditches, affected by beaver activity, and their changes after the dam removal. Chemical composition of surface water in ditches was analysed in sampling points above dam, below dam and in the ditch itself after removal of the dam; results compared to pristine beaver site nearby on a small stream. Results did not show significant differences between concentrations above and below dams. After removal of the dams, significant increase in DOC, N-NO3 -, N-NH4 + and TSS concentrations and significant decrease in TP concentrations were observed in some of the sites. Observed concentrations of all measured parameters were significantly lower in pristine beaver site than in beaver sites on drainage ditches.

Researches of the chemical composition of surface water in Ukraine, 1920-2020 (review)

The development of researches of the chemical composition of surface waters (rivers, lakes, reservoirs and ponds) is due to problems that are solved at one stage or another in the development of the country’s economy and are related to water quality issues. Depending on the tasks set during hydrochemical researches, attention is paid to a particular group of chemical components in water: 1) the main ions and their total amount (water mineralization); 2) dissolved gases; 3) biogenic elements; 4) organic matter; 5) microelements (including heavy metals); 6) radioactive elements; 7) specific pollutants. The article presents an analytical review of studies of the chemical composition of surface waters of Ukraine from the beginning of systematic research in the first half of the 20th century to the present day (1920-2020). The authors identified four typical chronological periods in the history of hydrochemical studies of surface waters in Ukraine. I period (1920s-1950s) – the beginning of systematic hydrochemical studies of surface waters; the appearance of regular observations of the chemical composition of water at the posts of hydrometeorological service on the Dnipro and Southern Bug rivers (1930s) and publication of these data in “Hydrological Yearbooks”; hydrochemical studies for selected large projects (Dnipro hydroelectric power station). II period (1950s-1970s) - expansion of hydrochemical research to meet the needs of water and hydropower construction, forecasting their possible impact on the country’s water resources; increasing the number of observation points for the chemical composition of water on large and medium-sized rivers; development of hydrochemistry of reservoirs. III period (1970s – at the beginning of the 2000s) – development of complex hydrochemical researches in the conditions of increasing anthropogenic load on water objects; creation of a system of hydrochemical monitoring of water bodies within the framework of the national system of observation and control of the environment (1973); application of sanitary and hygienic criteria for assessment of water quality – universal maximum acceptable concentrations (MAC); publication of quarterly “Hydrochemical Bulletins” (since 1967); development of radioecological studies of natural waters after the Chernobyl accident (1986); first publication in Ukraine of textbooks on hydrochemistry. IV period (after the beginning of the 2000s) – reformatting of hydrochemical research (monitoring system) to the requirements of the Water Framework Directive of the European Union, especially after the signing of the EU-Ukraine Association Agreement in 2014; reforming the water monitoring system based on environmental rationing with the identification of reference indicators; components of state monitoring of surface waters are the monitoring of biological, hydromorphological, chemical and physico-chemical parameters. The article also describes scientific hydrochemical schools: Institute of Hydrobiology of NAS of Ukraine; Taras Shevchenko National University of Kyiv; Ukrainian Hydrometeorological Institute of the State Emergency Service of Ukraine and NAS of Ukraine.

The dynamics of the chemical composition of surface water in the zone of influence of North-West Phosphorous Company JSC

Long-term monitoring studies of the chemical composition of water of Lake Komarinoe (Murmansk Region, North-West Russia) have been carried out in order to assess the quality of surface water in the territory of the development of the apatite-nepheline deposit Oleniy Ruchey. A clear reliable tendency has been revealed to increase the pH water value, mineralization, the content of basic ions, nitrate ion NO3 – in recent years, as well as a number of trace elements (Sr, Cu, Mo, F), several times higher than the maximum permissible concentrations of harmful substances for water of fishery ponds. According to the content of nutrients, the lake is characterized at the present time as eutrophic. The sharp increase in the content of compounds of the biogenic element (nitrogen) can lead to the bloom development of potentially toxic algae and cyanobacteria. Lake Umbozero, which receives water from Lake Komaninoe, is also at risk of developing water bloom processes and pollution.

Spatial Differences in the Chemical Composition of Surface Water in the Hornsund Fjord Area: A Statistical Analysis with A Focus on Local Pollution Sources

Surface catchments in Svalbard are sensitive to external pollution, and yet what is frequently considered external contamination may originate from local sources and natural processes. In this work, we analyze the chemical composition of surface waters in the catchments surrounding the Polish Polar Station in Svalbard, Hornsund fjord area. We have pooled unpublished and already published data describing surface water composition in 2010, related to its pH, electrical conductivity (EC), metals and metalloids, total organic carbon (TOC) and selected organic compound concentrations, including persistent organic pollutants (POPs) and surfactants. These data were statistically analyzed for spatial differences, using Kruskal–Wallis ANOVA and principal component analysis (PCA), with distance from the station in the PCA approximating local human activity impact. The geological composition of the substratum was found to be a strong determinant of metal and metalloid concentrations, sufficient to explain significant differences between the studied water bodies, except for the concentration of Cr. The past and present human activity in the area may have contributed also to some of the polycyclic aromatic hydrocarbons (PAHs), although only in the case of naphthalene can such an effect be confirmed by an inverse correlation with distance from the station. Other likely factors contributing to the chemical concentrations in the local waters are marine influence, long-range pollution transport and release from past deposition in the environment.

ОЧЕРК ИСТОРИИ ГИДРОХИМИИ ПОВЕРХНОСТНЫХ ВОД В УКРАИНЕ

The article presents an review of reserchs of the chemical composition of surface water in Ukraine from the beginning of systematic research in the first half of the twentieth century and to this day (1920-2020). Four characteristic chronological periods in the history of hydrochemical studies in Ukraine are identified. First period (1920s – 1950s) – the beginning of systematic hydrochemical studies of surface waters. Second period (1950s – 1970s) – the expansion of hydrochemical research to meet the needs of water and hydropower construction, the development of hydrochemistry of reservoirs. Third period (1970s – at the beginning of the 2000s) – development of integrated hydrochemical studies in the context of a growing anthropogenic load on water bodies; creation of a system of hydrochemical monitoring of water bodies within the framework of the national system of monitoring and environmental control. Fourth period (after the beginning of the 2000s) – reformatting of hydrochemical studies (monitoring systems) to the requirements of the European Union Water Framework Directive. The article also describes the scientific hydrochemical schools: Institute of Hydrobiology, NAS of Ukraine; Taras Shevchenko National University of Kyiv; Ukrainian Hydrometeorological Institute of the SES of Ukraine and NAS of Ukraine

Chemical composition of surface water in the main tributaries of Lake Baikal – the Selenga and the Barguzin Rivers

Lake Baikal is one of the oldest fresh water bodies on the planet, where the largest available water reserves are concentrated. River runoff plays an important role in the overall balance of substances entering the Lake. The Selenga River is the main tributary of Lake Baikal, in the basin of which, unlike other tributaries, a large number of industrial, agricultural, processing enterprises, settlements and cities are concentrated. The Barguzin River is the third largest river flowing into Lake Baikal, is the basin where intensive development in agriculture and forestry has undertaken. This paper presents the results of the analysis of surface water samples of the Selenga and Barguzin rivers collected during 2015-2016. In 2015, the water level for the Selenga and Barguzin rivers was characterized by extremely low water content, which caused an increase in the concentrations of major ions and trace elements in surface waters. The more favorable water regime in 2016 caused a significant decrease in ion concentrations. Maximum concentrations of iron and manganese are observed in winter and during flooding in the spring. In conditions of low water content, increased copper and zinc contents were also observed in the surface water of the Lake tributaries.

Application of multivariate statistical approach to identify trace elements sources in surface waters: a case study of Kowalskie and Stare Miasto reservoirs, Poland

The paper reports the results of measurements of trace elements concentrations in surface water samples collected at the lowland retention reservoirs of Stare Miasto and Kowalskie (Poland). The samples were collected once a month from October 2011 to November 2012. Al, As, Cd, Co, Cr, Cu, Li, Mn, Ni, Pb, Sb, V, and Zn were determined in water samples using the inductively coupled plasma with mass detection (ICP-QQQ). To assess the chemical composition of surface water, multivariate statistical methods of data analysis were used, viz. cluster analysis (CA), principal components analysis (PCA), and discriminant analysis (DA). They made it possible to observe similarities and differences in the chemical composition of water in the points of water samples collection, to uncover hidden factors accounting for the structure of the data, and to assess the impact of natural and anthropogenic sources on the content of trace elements in the water of retention reservoirs. The conducted statistical analyses made it possible to distinguish groups of trace elements allowing for the analysis of time and spatial variation of water in the studied reservoirs.

Rocks control the chemical composition of surface water from the high Alpine Zermatt area (Swiss Alps)

The study presents composition data of 87 surface water samples from high alpine catchments of the Zermatt area (Swiss Alps). The investigated area covers 170 km2. It was found that the surface runoff acquires the dissolved solids mostly by reaction of precipitation water with the minerals of the bedrock. Total dissolved solids (TDS) vary from 6 to 268 mg L−1. All collected water shows a clear chemical signature of the bedrock mineralogy. The contribution of atmospheric input is restricted to small amounts of ammonium nitrate and sodium chloride. NH4 is a transient component and has not been detected in the runoff. Evaporation is not a significant mechanism for TDS increase in the Zermatt area. The chemical composition of the three main types of water can be related to the mineralogy of the dominant bedrock in the catchments. Specifically, Ca-HCO3 (CC) waters develop from metamorphic mafic rocks and from carbonate-bearing schists. Mg-HCO3 water originates from serpentinites and peridotites. Ca-SO4 (CS) waters derive from continental basement rocks such as pyrite-rich granite and gneiss containing oligoclase or andesine. The collected data suggest that, together with reaction time, modal sulfide primarily controls and limits TDS of the waters by providing sulfuric acid for calcite (CC waters) and silicate (CS waters) dissolution. If calcite is present in the bedrock, its dissolution neutralizes the acid produced by sulphide weathering and buffers pH to near neutral to weakly alkaline conditions. If calcite is absent, the process produces low-pH waters in gneiss and granite catchments. The type of bedrock and its mineral assemblage can be recognized in water leaving very small catchments of some km2 area. The large variety of water with a characteristic chemical signature is an impressive consequence of the richly diverse geology and the different rock inventory of the local catchments in the Zermatt area.

An assessment of surface water chemistry with its possible sources of pollution around the Barapukuria Thermal Power Plant impacted area, Dinajpur, Bangladesh

This study aims at analyzing the current hydrochemical condition for understanding the factors and processes controlling the chemical composition of surface water with their possible relation to environmental pollution around the Barapukuria Thermal Power Plant (BTPP) impacted area. In this study, the Hill-piper diagram, ratio plots and cross plots were used to recognize the various hydrogeochemical mechanisms involved in the evolution of the water chemistry and quality around the area. The basic statistics, IQR value, correlation matrix, cluster analysis were appealed to implicate the complex interrelationships between the ionic components of water. The principal component (PC) and factor analysis (FA) were computed to detect the possible source of water environmental pollution influenced either by natural or multiple anthropogenic sources like BTPP, existing agriculture activity and so on. The Hill-piper diagram presents two distinct hydrochemical facies such as CaHCO3 and Ca-Mg-Cl facies. The PC/FA revealed that three principal components explained about 63.63% of the total variability. The factor 2 indicated active mixing environmental process like natural and anthropogenic influence. Whereas the high positive loading ions like SiO2, Cr3+, PO3-4, As3+, Cd2+ and Fe3+ of factors 1 and 3 represent the existence of industrial waste like BTPP while waste water with fly ash has high affinity with such components of water bodies. Thus these results confirmed that discharged from BTPP is the possible source of water environmental pollution for present and future.

Екобезпека водних об’єктів у зоні розташування підприємств теплоенергетики

This paper work evaluated the impact of Pridniprovsk thermal power stations on the ecological status of surface water in the area where is the object located. Particular attention was paid to the state of water in the area of the strait. Shyyanka because it is close to the ash dumps of the power station. The chemical composition of surface water studied and the content of the following components determined: sulfate ions, nitrate ions, nitrite ions, phosphate ions, chlorine ions, suspended solids, ammonia nitrogen, BSK5, heavy metals and oil products. The research results revealed the following. In certain places the value of mineralization (the strait. Shyyanka) were higher pH and sulfate ions. A river Dnieper observed an increase of chloride ions and total water hardness. Meanings of suspended solids exceed MAC almost 55 times. In the summer, their number is much higher than in the winter. The content of phosphate ions in surface waters near the power station almost 3 times more than MCL, leading to putrid processes in the pond. Consumption of such water for drinking can cause dermatitis in humans and violations of the gastrointestinal tract. In addition, analysis of the surface waters of substances such as oil and technical oils that do not have to be in the water, set the MCL of these substances almost 5 times more. Results about changing the chemical composition of the surface waters of the Dnieper in the operation of thermal power plants led to the following conclusions. In creating water intake, the averages of salt, can be estimated as fresh, hydrocarbonate-calcium type II. With the amount of ions they belong to Class I (general water status excellent), according to the degree of purity of category 1 (very clean), for including chloride water belongs to Class II (good), Category 3 (very clean), for including the sulfates class III (fair), Category 4 (slightly polluted). Generalized microbiological assessment characterizes the quality of water within the IV-V grade, 4-5 categories (mild - moderately polluted). The content of the toxic effect of pollutants and for the content of petroleum products water quality corresponds to category 7 (very dirty). Thus, the water quality in the Dnipro River and the Strait Shyyanka near the Prydniprovsk thermal power plant as a whole remains within category - fresh water. The degree of contamination of water is characterized Category 4 (slightly polluted), with the trend with transition into category 5 (moderately polluted). The content of oil condition of water corresponds to the category very dirty. In terms of mineral content (dry residue, sulfates, chlorides), pH, BSK5 water quality comply with the composition and properties of water surface sources of drinking water supply.

Hydromagnesite precipitation in the Alkaline Lake Dujiali, central Qinghai-Tibetan Plateau: Constraints on hydromagnesite precipitation from hydrochemistry and stable isotopes

The mineral hydromagnesite, Mg5(CO3)4(OH)2·4H2O, is a common form of hydrated Mg-carbonate in alkaline lakes, yet the processes involved in its formation are not well understood. This study focuses on Dujiali Lake, in the central Qinghai-Tibetan Plateau (QTP), which is one of the few environments on the earth's surface with extensive Holocene precipitation of hydromagnesite. The hydrogeochemistry of surface waters, and the mineralogical, stable isotope (δ13C and δ18O), and radiogenic isotope content of hydromagnesite deposits were analyzed to investigate formation mechanisms. The chemical composition of surface water around Dujiali Lake evolved from the rock-weathering-type waters of T1 (CaMgHCO3 water type) to more concentrated sodic waters of T2 (NaSO4Cl water type) due to evaporation. XRD results show that the mineralogical composition of samples is pure hydromagnesite. Analysis of oxygen isotopes in the hydromagnesite indicates that supergene formation with authigenic carbonate crystallization from evaporation water is the dominant precipitation process. Combined carbon-oxygen isotope analysis suggests atmospheric CO2 provided a carbon source for the precipitation of hydromagnesite. These findings suggest that hydromagnesite precipitation at Lake Dujiali is mainly inorganic in nature, and the greenhouse gas, CO2, is trapped and stored in the hydromagnesite directly from the atmosphere. AMS radiocarbon dating of samples indicates CO2 was sequestered between 5845 ± 30 to 6090 ± 25 cal a BP in the Dujiali Lake hydromagnesite deposit. The study contributes to improved understanding of hydromagnesite formation in modern and ancient playas.

Features of water chemical composition of oligotrophic and eutrophic bogs in the South of the Tomsk region

On the basis of the actual material the analysis of chemical composition of bog waters in the territory of the South of the Tomsk region is carried out. The data on average concentration of macro and trace components, organic matter, pH of bog waters are obtained. Significant distinctions in a chemical composition of surface water for different types of bogs are revealed. The composition and macrostructure of humic acids by the example of eutrophic bogs is studied.

The Specific Nature of Chemical Composition of Water from Volcanic Lakes Based on Bali Case Study

The research area was localized in the Indonesian Archipelago, at the latitude of eight and nine degrees S on the one of the Lesser Sunda group island provinces, Bali (563,3 km2). Two massive calderas (Mount Batur 1717 m above sea level.; Mount Sangiyang 2093 m above sea level) are one of the most prominent landforms in the chain of volcanic mountain ranges of the Bali Island. Lake Batur (17,18 km2) and Batur Spring (which are part of the freshwater lake system of Mt. Batur caldera) and also Danau Bratan Lake (one of the unconnected lakes next to the Mt. Sangiyang caldera), were selected for studies on the pollutants concentration levels in this volcanic area located in tropical climate. The research was aimed at determining the concentration of pollutants of natural (volcanic) and anthropogenic origin occurring in both lakes. The following parameters were determined: anions, metals, pH and conductivity. Based on the obtained dataset of initial studies it can be stated that the localization of aquatic ecosystems has the significant impact on the chemical composition of surface water.

Water migration of elements in Ornithogenic ecosystems of the North Pacific islands

Specific features of the chemical composition of surface water and water migration of elements in North Pacific islands with large population of marine colonial birds were analyzed. Ornithogenic factor was found to be determining in the composition of surface water in such ecosystems. The concentrations of nutrients (N, P, S, K) are informative hydrochemical parameters reflecting the effect of birds on the intensity of their migration in water. Spacious areas subjected to biogeochemical impact are formed around the islands populated by seabird colonies.

Spatial variations of surface water chemistry and chemical denudation in the Erdalen drainage basin, Nordfjord, western Norway

This study conducted over an investigation period of six years (2004–2010) focuses on spatial variation in chemical components of drainage water from sub-areas within a confined drainage basin of 79.5km2 (Erdalen drainage basin, inner Nordfjord, western Norway) for detection of spatial diversity and relation to environmental factors. The Erdalen drainage basin is homogenously composed of gneisses, which is reflected in a homogenous relative (as a percentage) chemical composition of surface water across the entire drainage basin system. At the same time, the mean annual TDS values of surface water sampled in creeks draining defined subsystems within Erdalen show a rather high spatial variability. The main controls of this spatial variability are (i) differences in slope deposit/regolith thickness, (ii) differences in slope angle, (iii) differences in areal regolith cover, (iv) differences in vegetation cover, (v) differences in snow cover and ground frost conditions, and (vi) differences in elevation (ma.s.l.). Altogether, the mean annual TDS values in Erdalen are rather low, which can be explained by (i) the shallow thickness of regolith across the very steep drainage basin, (ii) the small percentage of surface areas showing a significant cover of regolith, (iii) the cool climate in the fjord landscape of western Norway and (iv) the weathering resistance of the predominant gneisses within Erdalen. The annual chemical denudation rates in Erdalen are in a similar range of magnitude to rates published for numerous other cold environment catchments worldwide. Despite the rather low mean annual TDS values, chemical denudation is a comparably important and spatially very variable denudational process and should therefore not be neglected when studying slope development as well as slope- and catchment-wide denudation rates and mass budgets in this kind of steep, mountainous cold climate drainage basins.