Sulphur and Heavy Metal Concentrations in Scots Pine Bark in Northern Finland and the Kola Peninsula

Sulphur and heavy metal deposition in northern Finland (= in Lapland) and the Kola Peninsula were surveyed using Scots pine bark samples. Sulphur concentrations in bark close to the Kola smelters were on an average twice as high as on the Finnish side of the border. The Cu and Ni concentrations near the smelters were almost 100-fold the mean values in northern Finland. There was a marked decrease in the sulphur and heavy metal concentrations with increasing distance from the emission sources. The effects of emission from the Kola Peninsula were evident in Finland only close to the border, especially in the eastern parts of Inari (NE corner of Lapland) where the Cu and Ni concentrations were 2- to 6-fold those in western Lapland. The sulphur and heavy metal concentrations in most of northern Finland were low. However were the concentrations of Cr in bark in the SW corner of Lapland considerably high, due to the emissions from the Tornio refined steel plants.     

Acid deposition from the Russian Kola Peninsula: Are sensitive fish populations in north-eastern Finnish Lapland affected?

Sulphur emissions from Russian Kola Peninsula smelters are known to cause surface water acidification in the border areas between Norway and Russia. The sulphur deposition is also high in the eastern part of Finnish Lapland. In 1990, a monitoring programme was started to survey the effects of acid deposition on sensitive fish populations in north-eastern Finnish Lapland. Altogether 103 sites in three areas were electrofished and autumn water samples were taken. Besides the brown trout (Salmo trutta), special attention was paid to the occurrence of minnow (Phoxinus phoxinus) since it is a common species in small waters and is highly sensitive to acidification. During the first three years of monitoring no signs of acidification were recorded. The alkalinity values of brooks generally exceeded 0.1 mmol/1. Brown trout, minnow and burbot (Lota lota) were caught frequently in the study sites. Later the study was focused on the uninhabited Vätsäri area which is receiving the highest sulphur deposition in Finnish Lapland. The alkalinity values of the sampled brooks were in most cases below 0.05 mmol/1, indicating a decreased buffer capacity. However, the electrofishing of the brooks showed no acid-induced damage. The lowest alkalinity values were detected from a group of small upland ponds. In four such ponds the alkalinity was zero or negative. No minnows were caught from these four ponds apart from one, where the minnows were exceptionally large. The results show that the waters near the eastern border of northern Finnish Lapland are threatened by acidification. No damage to fish populations subject to fishing was observed. The absence of minnows in some small waters is possibly the first sign of acid-induced fish population damage.     

Dose-response relationships for the addition of limestone to lakes and ponds in the Northeastern United States

A titration based model (DeAcid) has been used to predict treatment dose and times for reacidification for CaCO₃-treated lakes in the Living Lakes, Inc. (LLI) aquatic liming program. Water quality constitutents (pH, ANC and Ca) were used to measure the effectiveness of the dosing model and reacidification rates. Data from 22 lakes or ponds in 5 northeast states have been collected since June 1986. With few exceptions, pH and ANC values ranged from 4.5 to 6.5 and ?30 to +65 ueq L^?1, respectively, in untreated sites and 6.5 to 7.8 and 120 to 300 ueq L^?1, respectively, in sites approximately 30 days after treatment. Changes in Ca concentration levels have been used to evaluate the utility of the dose model for treatment of both inland and coastal waters. For coastal, seepage lakes application of a single-box mass transfer model to observed post-liming changes in ANC and Ca adequately simulates lake response.     

Element Concentrations in Scots Pine Needles on Radial Transects Across a Subarctic Area

Concentrations of aluminium (Al), arsenic (As), calcium (Ca), cadmium (Cd), chlorine (Cl), chromium (Cr), copper (Cu), iron (Fe), potassium (K), magnesium (Mg), manganese (Mn), nickel (Ni), phosphorus (P), lead (Pb), sulphur (S), silicon (Si) and zinc (Zn) were measured by X-ray fluorescence spectrometry (XRF) in Scots pine needles collected from transects across Finnish Lapland and the Kola Peninsula in Russia. Ni, Cu, Fe, P and S concentrations were significantly higher in the needles collected in the vicinity of the smelters in Monchegorsk, whereas Mn and Zn decreased towards Monchegorsk. No distinct increase of S or decrease of Mn and Zn concentrations in the needles were observed when approaching Nikel. Foliar S concentrations were higher in C needles than in C+1 needles, even in plots close to the smelters. The effect of the emissions from the smelters was clearly seen in the needle chemistry up to 50 km away from smelters and was still perceivable over 100 km away.     

sulphur isotope composition of stream water,moss and humus from eight arctic catchments in the Kola Peninsula region (NW Russia,N Finland,NE Norway)

In summer 1994, stream water, moss and humus samples were collected for sulphur isotopic analysis from eight catchments located in the western Kola Peninsula region, where several industrial centres emit high loads of SO₂ and other elements to the atmosphere. Three potential sources of sulphur and their isotopic signatures were identified: (1) marine (δ ³⁴S+20 to +21‰ CDT), (2) anthropogenic emissions (<+10‰), and (3) geogenic (variableδ ³⁴S, mostly <+10‰). Averaged per catchment, the sulphur isotopic composition varies between +6.0 and +16.3‰ for stream water sulphate, +6.0 and +8.4‰ for moss sulphur, and +5.2 and +12.2‰ for humus sulphur. Theδ ³⁴S composition of stream water from the more remote catchments is quite variable, reflecting several natural (geogenic) sources, but it becomes restricted to the range +8 to +10‰ near the pollution sources. A plot ofδ ³⁴S vs. 1:SO₄ in stream water suggests that sulphate originating from the smelters has aδ ³⁴S value ≈+9.5‰, and is a dominant source. Sulphur isotope values for moss and humus are consistent with the deduced composition for the emitted sulphur, though for humus a component of geogenic sulphur incorporated via vegetation uptake may play a role. Further isotopic characterisation of atmospheric emissions, together with environmental samples, is needed to better understand sulphur sources and sinks in the area.     

Trends in the Chemistry of Acidified Bohemian Lakes from 1984 to 1995: I. Major Solutes

Temporal changes in major solute concentrations in six Czech Republic lakes were monitored during the period 1984–1995. Four chronically-acidic lakes had decreasing concentrations of strong-acid anions (C_SA = SO₄ ^2- + NO^{3 -} + Cl^-), at rates of 3.0 to 9.0 μeq L^-1 yr^-1. Decreases in SO₄ ^2-, NO₃ ^-, and Cl^- (at rates up to 5.1 μeq L^-1 yr^-1, 3.2 μeq L^-1 yr^-1, and 0.6 μeq L^-1 yr^-1, respectively) occurred. The response to the decrease in deposition of S was rapid and annual decline of SO₄ ^2- in lake water was directly proportional to SO₄ ^2- concentrations in the acidified lakes. Changes in NO₃ ^- concentrations were modified by biological consumption within the lakes. The decline in C^SA was accompanied in the four most acidic lakes by decreases in Al_T, increases in pH at rates of 0.011 to 0.016 pH yr^{- 1}, and decreases of Ca²⁺ and Mg²⁺ (but not Na⁺) in three lakes. The acid neutralizing capacity (ANC) increased significantly in all six lakes. Increases in base cation concentrations (CB = Ca²⁺ + Na⁺ + Mg²⁺ + K⁺) were the principal contributing factor to ANC increases in the two lakes with positive ANC, whereas decrease in C_SA was the major factor in ANC increases in the four chronically-acidic lakes. The continued chemical recovery of these lakes depends on the uncertain trends in N deposition, the cycling of N in the lakes and their catchments, and the magnitude of the future decrease in S deposition.     

Critical loads of acidity to surface waters

The critical load of acidity to surface water is based on the condition that the inputs of acids to a catchment do not exceed the weathering rate less a given amount of ANC (Acid Neutralizing Capacity). The Steady State Water Chemistry (SSWC) Method is used to calculate critical loads of acidity, using present water chemistry. To calculate the weathering, the so-called F-factor is used to estimate the part of the base cation flux that is due to soil acidification. The F-factor has been estimated empirically from historical data comparisons from Norway, Sweden, U.S.A. and Canada and is considered to be a function of the base cation concentration by the formula: F=sin(BC^*/S), where BC^* is the present base cation concentration and S the base cation concentration at which F=1. At higher values for BC^* F is set to 1. For Norway, Sweden and Finland S has been set to 400 μeq/l (ca. 8 mg Ca/l), giving F-values in the range 0.05–0.2. The importance of the F-factor in the calculations of the critical loads of acidity for Nordic surface waters was tested by calculating the magnitude of the area where the critical load of acidity is exceeded in Norway for different values of S. Similar calculations were carried out for the Finnish and Swedish lake data. Varying S from 100 μeq/l to 1200 μeq/l, the exceeded area in Norway decreases from 31,9 to 28,3%. For F=0 (S=∞, i.e. assuming no soil acidification), the exceeded area is reduced to 27,2%. For Finland and Sweden the the percent of lakes exceeded are reduced from 16,6 to 12,9% and 30 to 23,6%, respectively. For F = 0 the percent of lakes exceeded are reduced to 11,4 and 16,4, repectively. These results indicate that the F-factor is not of great importance for calculating critical load and critical load exceedances in Norway, Finland and Sweden.     

Finnish lake survey: the role of organic and anthropogenic acidity

A lake survey consisting of 987 randomly selected lakes was conducted in Finland in autumn 1987. The survey covered the whole country, and the water quality of the lakes can be considered as representative of the approximately 56 000 lakes larger than 0.01 km² in Finland. The median TOC concentration is 12 mg L^-1 and the median pH 6.3. The proportion of lakes with TOC concentrations > 5 mg L^-1 in the whole country is 91 %. Organic anion is the main anion in the full data set (median 89 μeq L^-1). The high organic matter concentrations in Finnish lakes are associated with catchment areas containing large proportions of peatlands and acid organic soils under coniferous forest. The survey demonstrated that organic matter strongly affects the acidity of lakes in Finland. The decreasing effect of organic matter on the pH values was demonstrated by both regression analysis and ion balances. At current deposition levels of ^*SO₄ the pH of humic lakes in Finland is determined to a greater extent by high TOC concentrations than by ^*SO₄ in most areas. In lakes with pH values lower than 5.5 the average organic anion contribution is 56 % and non-marine sulfate contribution 39 %. However, in the southern parts of the country, where the acidic deposition is highest, the minerogenic acidity commonly exceeds the catchment derived organic acidity.     

GIS Analysis of Surface Water Chemistry Susceptibility and Response to Industrial Air Pollution in the Kola Peninsula,Northern Russia

The Kola Peninsula (Figure 1) is the most industrially developed and urbanized region in the Russian North. The main pollution sources are the large smelters Severonickel and Pechenganickel, which are responsible for > 80 % of SO2 emission and nearly 100 % of the Ni and Cu emission in the region. The heterogeneous structure of the hydrologic network and geochemistry across the region cause natural variability in water chemistry. Due to moist and cool climate, large territories on the Kola are sensitive to acid precipitation, but around the smelters, geological peculiarities, erosion and alkaline dust emissions increase buffering capacity of waters to acidification. Lake and river monitoring implemented from 1989-1993 by the laboratory of water ecosystems, Institute of Northern Ecology Problems was a basis for GIS-analysis (ARC/VIEW-2.1) of the major constituents of water chemistry attributed to anthropogenic load in the region. After correction for sea salt, acid-neutralizing capacity (ANC) of waters was calculated. The highest concentrations of anthropogenic non-sea sulfates were confined to the districts with high cation concentrations (Na+ + K+ + Ca2+ + Mg2+) that reduced negative effects. The most vulnerable regions were found in the northern tundra and high mountain tundra.     

Seasonal and long-term temporal patterns in the chemistry of Adirondack lakes

There is considerable interest in the recovery of surface waters from acidification by acidic deposition. The Adirondack Long-Term Monitoring (ALTM) program was established in 1982 to evaluate changes in the chemistry of 17 Adirondack lakes. The ALTM lakes exhibited relatively uniform concentrations of SO₄ ^2?. Lake-to-lake variability in acid neutralizing capacity (ANC) was largely due to differences in the supply of basic cations (Ca²⁺, Mg²⁺, K⁺, Na⁺; C_B) to drainage waters. Lakes in the western and southern Adirondacks showed elevated concentrations of NO₃ ^?, while lakes in the central and eastern Adirondacks had lower NO₃ ^? concentrations during both peak and base flow periods. The ALTM lakes exhibited seasonal variations in ANC. Lake ANC was maximum during the late summer or autumn, and lowest during spring snowmelt. In general Adirondack lakes with ANC near 100 Μeq L^?1 during base flow periods may experience decreases in ANC to near or below 0 Μeq L^?1 during high flow periods. The ALTM lakes have exhibited long-term temporal trends in water chemistry. Most lakes have demonstrated declining SO₄ ^2?, consistent with decreases in SO₂ emissions and SO₄ ^2? in precipitation in the eastern U.S. Reductions in SO₄ ^2? have not coincided with a recovery in ANC. Rather, ANC values have declined in some ALTM lakes. This pattern is most likely due to increasing concentrations of NO₃ ^? that occurred in most of the ALTM drainage lakes.     

Acid deposition and lake chemistry in southwest China

A water quality survey has been performed on selected lakes and streams in southwest China. The purpose of the study was to measure the concentrations of acidic deposition and surface water chemistry in a region of severe air pollution, forest decline, and relatively sensitive geology to acidic deposition. We show that, although there are some high elevation lakes of low acid neutralizing capacity (ANC<150μeq L^?1, acidification of lakes has not occurred in southwest China due to production of base cations in soil and dry deposition of dust that serves to neutralize acidic deposition. Water chemistry is buffered by high base cation concentrations (Ca²⁺, Mg²⁺, Na⁺, and K⁺ greater than 300μeq L^?1, and pH values are always greater than 6.5.     

Temporal trends in low alkalinity lakes of the Upper Midwest (1983–1989)

The Upper Midwest contains a large concentration of low alkalinity lakes located across a west to east gradient of increasing deposition acidity. We present temporal trends in the chemistry of 28 lakes (4 in Minnesota, 13 in Wisconsin, and 11 in Michigan) representative of the acid-sensitive resource of the region. Lakes were sampled three times per year between 1983 and 1989. Temporal trends in SO₄ ^2? were all negative in direction, consistent with a regional decline in SO₂ emissions and atmospheric SO₄ ^2? deposition. However, these trends occurred predominantly in higher ANC (100 to 225 Μeq L^?1), non-seepage lakes and were associated with increases in ANC and pH in only one of the 8 lakes. ANC decreased in a second group of lakes, usually in concert with decreased [Ca²⁺+Mg²⁺], a response we associate with a severe drought. Disruptions in hydrologic flowpaths caused one lake to acidify rapidly after inputs of ANC-rich groundwater ceased and appeared to cause ANC and [Ca²⁺+Mg²⁺] declines in a second lake by reducing stream-water inflow. Our analysis was thus complicated by hydrochemical effects of climatic variability, which confounded trends related to acidic deposition. Periods longer than 6 yr are needed to transcend climatic signals and verify subtle trends related to atmospheric pollutants.     

Relation between sulphur concentrations in the Scots pine needles and the air in northernmost Europe

The SO₂ emissions from the Kola Peninsula in Arctic Russia (totalling around 600 Gg(SO₂) yr^–1 at the beginning of the 1990s) produce an atmospheric SO₂ concentration gradient to the northernmost Europe. This gradient covers the range from >50 g m^–3 in the vicinity of the sources to 1 g m^–3 in Finnish Lapland. In the present study, the measured sulphur concentrations in Scots pine needles were compared with the estimated distribution of atmospheric SO₂. The total sulphur concentrations in the needles ranged from 741 to 2017 mg kg^–1. Strongly elevated concentrations (> 1200 mg kg^–1) were found within 40 km from the smelters corresponding to an area where the annual mean atmospheric SO₂ concentration exceeded 10 g m^–3. The foliar sulphur concentrations (total, organic and inorganic) show a high correlation with the estimated mean SO₂ concentration distribution in the air. Consequently the foliar sulphur concentrations reflected the atmospheric sulphur load well. The data presented here show that uptake via stomata is an important deposition pathway also in the arctic conditions with a short growing season.     

SOURCES OF TRACE METALS IN STREAMS AND HEADWATER LAKES IN FINLAND

Distributions of Mn, Zn, Cu, Ni, Cr, Pb, As, and Cd in Finnish surface waters were studied by comparing two data sets: samples from 154 headwater lakes collected by the Water and Environment Administration in 1992 and samples from 1165 headwater streams collected during the environmental geochemical mapping program of the Geological Survey of Finland in 1990. It was expected that headwater lakes with catchments smaller than 1 km² and high lake percentage (ratio of lake area to catchment size) would be more influenced by atmospheric trace metal deposition than the streams, with average catchment size of 30 km². The lakes with highest arsenic concentrations lie in an area with greenstones and arsenic-rich black schists. The same lakes have high copper concentrations, which evidently are derived from the Cu-rich greenstones of the catchment. The high copper concentrations of streams and lakes in the industrialized region of the southwest coast are due to several anthropogenic sources. The highest concentrations of chromium occur in brown stream and lake waters rich in humic matter, while manganese and zinc concentrations, which are controlled by acidity, tend to be elevated in low-pH waters. The high nickel concentrations in lakes in southwestern Finland probably are due to anthropogenic input, while Ni anomalies in stream and lake water in eastern Finland are correlated with high Ni contents of glacial till. The lead concentrations in lakes are mainly of airborne anthropogenic origin. The pattern of atmospheric deposition is reflected in the concentrations of Cd, As, Cu, Zn, and Ni in headwater lakes, but land-use, the natural distribution of metals in the overburden, water acidity, and the amount of humic substances influence the distribution of trace metals in both lakes and streams. Thus the trace metal distribution in headwater lakes cannot be used alone to estimate the contribution of anthropogenic atmospheric deposition to metal anomalies in Finnish surface waters.     

Effect of industrial emissions on membrane permeability of epiphytic lichens in Northern Finland and the Kola Peninsula industrial areas

The impact of air pollution on membrane permeability of the epiphytic lichens Hypogymnia physodes and Bryoria fuscescens was studied in northern Finland and the Kola Peninsula to assess the effects of the Kola industrial emissions. The conductivity and quantity of K⁺ in leachates of the lichens were determined both as absolute and relative leakage. The K⁺ leakage from the lichens was the most sensitive indicator of membrane disturbance. Positive relationships between K⁺ leakage and decreasing distance from pollution sources and modelled atmospheric SO₂ concentrations were found and the K⁺ leakage and Cu and Ni concentrations of Scots pine bark were also highly correlated. The relative conductivity of leachates was inversely related to distance from sources, while the absolute conductivity of leachates from lichens was positively correlated with bark S. The ion leakage was higher in fruticose Bryoria fuscescens than in foliose Hypogymnia physodes, but the overall response to pollution was similar in both species. The methods used were able to identify areas of disturbed membrane function around the Kola industrial areas and local point sources in northern Finland. However, the majority of the studied sites in Finnish Lapland can be regarded as undisturbed background areas with respect to these sensitive lichens.     

Effects of Acidification Due to Emissions from the Kola Peninsula on Fish Populations in Lakes Near the Russian Border in Northern Norway

In this paper we document the effects of acidification on fish populations in lakes in Sør-Varanger near the Russian border in northern Norway. We used questionnaires in order to assess the current status and distribution of different fish species, and conducted test-fishing to determine relative abundance (CPUE-T) and age structure. Acidification of surface waters in this area is due to emissions of SO₂ from smelters on the Kola Peninsula in Russia (Nikel and Zapoljarnij) between 10 and 30 km from the Norwegian border. Sulphur deposition in Sør-Varanger ranges from 0.6 to 2.0 g S m-² yr-¹, which is similar to levels in the most acidified areas in southern Norway. However, a dominant fraction of the acidic deposition reaches the ground in particulate form during summer and autumn. Coastal areas in Sør-Varanger receive small amounts of precipitation; the annual mean is 580 mm. We obtained fish status from 401 lakes, about 40% of all lakes larger than 3 ha, which were inhabited by 236 and 293 populations of Arctic charr (Salvelinus alpinus) and brown trout (Salmo trutta), respectively. The extent of fish damage was small as only three populations of Arctic charr were lost, while three populations of Arctic charr and eight populations of brown trout were at various stages of reduction. Damaged and lost fish populations were identified in smaller lakes at relatively high elevations (172–349 m) in six areas in the Jarfjord Mountains, covering a land area of 30.0 km². Most of the damage probably occurred during the 1970s and 1980s. In lakes that supported or had supported Arctic charr and brown trout, we found a significant relationship between CPUE-T, and acid neutralizing capacity (ANC) and pH, and also between alkalinity and the concentration of inorganic Al for brown trout. In both species, the catch of fish in age groups 1+ and 2+ (CPUE-R) increased significantly with CPUE-T. Affected populations typically exhibited irregular age composition, and age-classes were missing, indicating that reductions in fish populations were due to recruitment failure. The limited fish damage is related to relatively good catchment resistance to acidic inputs, small amounts of wet deposition as well as precipitation. These conditions result in low accumulation of acidic compounds, producing less acidic run-off waters and few episodes of unfavourable water quality.     

Change in the acid-base status of an appalachian mountain catchment following forest defoliation by the gypsy moth

Infestation by the gypsy moth (Lymantria dispar) can alter biogeochemical conditions in affected catchments. Stream-water concentration data obtained over the period of 1980–1993 for White Oak Run, a stream in Shenandoah National Park, Va., indicate that change in catchment acid-base status is associated with forest defoliation by the moth larva. Stream-water concentration changes following defoliation included increasing concentrations of strong-acid anions, base-cations, and hydrogen ion, as well as decreasing concentrations of acid-neutralization capacity (ANC) and sulfate. The largest change was in the concentration of nitrate; annual discharge-weighted mean concentrations increased from predefoliation levels consistently less than 5 μeq L^?1 to postdefoliation levels greater than 50 μeq L^?1. An intensification of acidification was indicated by record-high hydrogen ion concentrations and record-low ANC concentrations. The long-term biogeochemical implications of the infestation are uncertain due to the nonlinearity of the observed responses and unknown patterns of recovery and recurrence.     

Chemistry of soft-water seepage lakes in the upper midwest: Lacustrine alkalinity production in summer

A total of 26 soft-water, seepage lakes in the Northern Highlands (NH) of Wisconsin (N =16) and the Upper Peninsula (UP) of Michigan (N=10) were sampled four times between early May and mid October 1984 as part of the ‘PIRLA’ Project (Paleolimnological Investigations of Recent Lake Acidification). Because of low antecedent recharge of the local water-table, this ‘summer’ interval likely featured minimal groundwater inputs (<2 cm over lake surface) to most of these seepage lakes. Based on this hydrogeologic relationship, and on regional deposition data, I evaluated short-term net epilimnetic (June–August) and whole-lake (May–October) sediment-water exchange of ANC, base cations, acid oxy-anions, Al, DOC and silicic acid in these lakes using a simplified mass balance algorithm. Silica, nitrate and ammonium were all efficiently retained in these seepage lakes. The assimilation of NO₃ ^? (19±4 meq m^?2) slightly exceeded assimilation of NH₄ ⁺ (16±4), resulting in a net internal ANC production of only +3 meq m^?2 over 161 d between early May and mid October 1984. Over this same interval ANC production resulting from lacustrine S retention averaged +35±8 meq m^?2 in the NH, but was too variable to be statistically significant (+21±21 meq m^?2) in the UP. Epilimnetic S retentions in mid summer were more comparable (21±4 in NH; 14±5 meq m^?2 in UP). McNearney Lake (UP) illustrates how high sulfate, linked to low alkalinity, high Al, low P, and low productivity, can become a negative correlate of lacustrine S retention. Temporal changes in base cations in the 26 lakes were generally small and erratic compared with uncertainties in deposition inputs and analytical errors, rendering estimates of related ANC production inconclusive. Even small analytical biases can be critical when designing and interpreting lake monitoring studies.     

Acidity status of surface waters in Massachusetts

The Massachusetts Acid Rain Monitoring project surveyed 80.5% of the state's 5294 named water bodies between 1983 and 1985. PH and acid neutralizing capacity (ANC) were measured monthly the first 14 mo and semi-annually afterwards. Sample collection and analysis were performed by volunteers. The majority of surface waters in Massachusetts were found to be sensitive to possible long term acidification, with 63% exhibiting ANC less than 200 μeq L^?1 and 22% with ANC less than 40 μeq L^?1. Seasonal patterns in ANC were observed, the median ANC being 384 μeq L^?1 in summer/fall and 134 μeq L^?1 in winter/spring. Geographical differences were also found across the state: the streams and lakes with lowest pH and ANC were located in the southeastern and north-central parts of the state, while the most alkaline surface waters were found in the western-most part of the state, which is the only area of the state with significant limestone deposits.