Seasalt Effects on the Acid Neutralizing Capacity of Streamwaters in Southern Norway

1995 ◽  
Vol 26 (4-5) ◽  
pp. 369-388 ◽  
Author(s):  
Espen Lydersen ◽  
Arne Henriksen
Keyword(s):  
Stream Water ◽  
Base Cations ◽  
Acid Neutralizing Capacity ◽  
Neutral Salt ◽  
Exchange Reactions ◽  
Short Term ◽  
Sulphur Compounds ◽  
Neutralizing Capacity ◽  
Southern Norway

Input of neutral salt, primarily NaCl, from sea spray is an important factor for short-term acidification of surface water, primarily in already acidified areas, because Na may substitute for H+ and cationic aluminium by cation-exchange reactions in the soil. By evaluating the variation of non-marine sodium (Na*) separately it is possible to estimate the major effect of seasalt episodes on the neutralizing capacity (ANC) of stream water. At four long-term monitored Norwegian catchments, the Na* in stream water on average explained 28 ± 4% of the monthly variations of ANC in stream water at Birkenes, and 27 ± 3%, 20 ± 2% and 56 ± 5% of the correspondent variations at Storgama, Langtjern and Kaarvatn, during the respective monitoring periods. The remaining variations in acid neutralizing capacity are explained by the difference between non-marine base cations (ΣCa*,Mg*,K*) and non-marine sulphate (SO4*) and NO3. This paper also indicates that seasalt episodes are probably of greater importance for the periodic variations in ANC of stream water than commonly recognized. During the last years, extreme seasalt episodes have occurred in southern Norway, and more frequently at winter-time, which means that seasalt inputs have played a more important role for the short-term variations of ANC in stream water the last years. This tendency is also strengthened by the fact that there has been a significant decline in the input of acidic sulphur compounds and non-marine base cations in stream water during the last 10-15 years. Because the decline in soil-derived base cations in stream water is somewhat lower than the correspondent decline of sulphate, a slowly improving ANC of stream water should be expected on long-term basis. Seasalt episodes of the same magnitude as those present during the last years, will therefore most likely cause less extreme water-chemical conditions in the years to come. Because the seasalt effect seems to be a short-term effect, there is no reason to claim that these effects may cause long-term acidification, a conclusion earlier drawn from several correspondent studies.

scholarly journals Long-term trends of water chemistry in mountain streams in Sweden – slow recovery from acidification

2014 ◽  
Vol 11 (1) ◽  
pp. 173-184 ◽  
Author(s):  
H. Borg ◽  
M. Sundbom
Keyword(s):  
Water Chemistry ◽  
Stream Water ◽  
Base Cations ◽  
Acid Neutralizing Capacity ◽  
Precipitation Trend ◽  
Run Off ◽  
Neutralizing Capacity ◽  
Recovery From Acidification ◽  
Long Term Trends

Abstract. The water chemistry of streams and precipitation in the province of Jämtland, northern Sweden has been monitored since the 1980s to study long-term trends, occurrence of acid episodes, and effects of liming. The acidity in precipitation increased in the 1970s, followed by a loss of acid neutralizing capacity (ANC) and low pH in the streams. Sulfur deposition began to decrease in the 1980s, until approximately 2000, after which the decrease levelled out. Stream water sulfate concentration followed the precipitation trend but decreased more slowly and since the late 1990s a subtle increase was observed. Sulfate concentrations in the snow typically have been higher than or equal to the stream sulfate levels. However, during the period of rapid deposition decrease and also since 2005 stream sulfate has sometimes exceeded snow sulfate, indicating desorption of stored soil sulfate, possibly because of climate-related changes in run-off routes through the soil profiles, following shorter periods of frost. From 1982 to 2000, total organic carbon (TOC) increased by approximately 0.1 mg L−1 yr−1. The mean trends in sulfate and TOC from approximately 1990 until today were generally opposite. Acidic episodes with pH 4.0 at flow peaks occurred frequently in the unlimed streams, despite relatively well-buffered waters at baseflow. To evaluate the main causes for the loss of ANC during episodes, the changes in major ion concentrations during high flow episodes were evaluated. The most important factors contributing to ANC loss were dilution of base cations (Na+, K+, Ca2+, Mg2+), enrichment of organic anions and enrichment of sulfate. Wetland liming started in 1985 after which the earlier observed extreme peak values of iron, manganese and aluminium, did not reoccur. The studied area is remote from emission sources in Europe, but the critical load of acidity is still exceeded. The long-term recovery observed in the unlimed streams is thus slow, and severe acidic episodes still occur.

Changes in streamwater chemistry after 20 years from forested watersheds in New Hampshire, U.S.A.

2000 ◽  
Vol 30 (8) ◽  
pp. 1206-1213 ◽  
Author(s):  
C W Martin ◽  
C T Driscoll ◽  
T J Fahey
Keyword(s):  
New Hampshire ◽  
Forest Succession ◽  
Stream Water ◽  
Base Cations ◽  
Acid Neutralizing Capacity ◽  
N Saturation ◽  
Old Growth ◽  
Streamwater Chemistry ◽  
Old Growth Forest ◽  
Neutralizing Capacity

Long-term patterns of streamwater chemistry provide valuable evidence of the effects of environmental change on ecosystem biogeochemistry. Observations from old-growth forests may be particularly valuable, because patterns should not be influenced by forest succession. Water samples were collected biweekly from four streams in, and near, the old-growth forest watershed of the Bowl Research Natural Area in the White Mountains of New Hampshire from May 1973 through October 1974, and from June 1994 through June 1997. Average NO3– concentrations, which ranged from 40.8 to 46.1 µequiv.·L-1 in 1973-1974, declined significantly to averages of 14.9-20.1 µequiv.·L-1 during 1994-1997. Concentrations of the base cations, Ca2+ and Mg2+, also declined in stream water between the two sampling periods. The northeastern United States, including the study area, has been subjected to elevated atmospheric deposition of sulfur and nitrogen for more than 40 years. This observation has led to the concern that mature forest ecosystems may exhibit N saturation and depletion of Ca2+ from exchangeable soil pools. While the Bowl exhibits a pattern of elevated concentrations of NO3– throughout the year, suggestive of conditions of N saturation, concentrations have declined markedly over the last 20 years. Concentrations of Ca2+ have also declined suggesting possible depletion from the exchangeable soil pool, but the acid neutralizing capacity of stream water has remained constant or increased, indicating resistance to additional acidification.

Short-Term Changes in the Acid/Base Chemistry of Two Acidic Lakes Following Calcium Carbonate Treatment

1989 ◽  
Vol 46 (2) ◽  
pp. 306-314 ◽  
Author(s):  
G. F. Fordham ◽  
C. T. Driscoll
Keyword(s):  
New York ◽  
Dissolved Inorganic Carbon ◽  
Initial Perturbation ◽  
Acid Neutralizing Capacity ◽  
Short Term ◽  
Acidic Lakes ◽  
Neutralizing Capacity ◽  
Rapid Dissolution ◽  
Additional Release ◽  
Woods Lake

Woods Lake and Cranberry Pond, two chronically acidic lakes located in the Adirondack region of New York, USA, were intensively monitored following CaCO3 treatment in May 1985 to evaluate the mechanisms controlling short-term changes in water column chemistry. Immediately following base application (24 h), both lakes responded like systems closed to atmospheric CO2, because the dissolution of very small CaCO3 particles (median diameter 2 μm) exceeded the rate of atmospheric CO2 intrusion. Rapid dissolution of CaCO3 coupled with very low concentrations of dissolved inorganic carbon (DIC) prior to treatment, resulted in pH increases in the upper mixed waters from 4.9 to 9.4 in Woods Lake and from 4.6 to 9.1 in Cranberry Pond, as waters readily became saturated with CaCO3. pH increases were accompanied by stoichiometric increases in dissolved Ca2+, acid neutralizing capacity (ANC), and DIC. Following this initial perturbation, the upper mixed waters equilibrated with atmospheric CO2 over a 4 wk period, facilitating additional release of dissolved Ca2+ and ANC due to dissolution of suspended CaCO3. The amount of CaCO3 that dissolved during the 4 wk immediately following treatment, calculated from Ca2+ budgets, was very high; 86% in Woods Lake and 79% in Cranberry Pond.

Modelling stream water chemistry with snowmelt

1984 ◽  
Vol 305 (1124) ◽  
pp. 427-439 ◽  
Keyword(s):  
Ion Exchange ◽  
Water Chemistry ◽  
Seasonal Variations ◽  
Stream Water ◽  
Acid Precipitation ◽  
Exchange Reactions ◽  
Stream Water Chemistry ◽  
Reservoir Models ◽  
Southern Norway ◽  
Adsorption Desorption

Simple hydrochemical reservoir models based on the mobile anion concept are described for the Birkenes and Storgam a catchments in southern Norway with acidified stream water. Key processes modelled include water routing, sulphate adsorption-desorption, ion-exchange reactions, weathering and a gibbsite equilibrium condition. The models reproduce much of the daily and seasonal variations in stream water chemistry which have been observed over several years. Model considerations have been used in an attempt to explain the acidification of stream water in these two areas. It is hypothesized that soil acidification has occurred and that acid precipitation is at least partly responsible. The results are tentative largely because the models are derived from present-day stream water chemistry.

Base cation reservoirs in soil control the buffering capacity of lakes in forested catchments

2006 ◽  
Vol 63 (3) ◽  
pp. 471-474 ◽  
Author(s):  
Daniel Houle ◽  
Rock Ouimet ◽  
Suzanne Couture ◽  
Christian Gagnon
Keyword(s):  
Surface Water ◽  
North America ◽  
Surface Waters ◽  
Base Cations ◽  
Base Cation ◽  
Acid Neutralizing Capacity ◽  
Forested Catchments ◽  
Northeastern North America ◽  
Poor Recovery ◽  
Neutralizing Capacity

The acidification of forest soils and surface waters and their relatively poor recovery record following reductions in atmospheric sulphur emissions is a major ongoing environmental problem, particularly in northeastern North America. The slow recovery of surface water is widely hypothesized to result from depletion of reservoirs of base cations in soil. This is concordant with the theory that the acid-neutralizing capacity (ANC) of lakes is likely proportional to the size of the exchangeable base cation reservoirs present in surrounding watershed soils. However, data describing these linkages are still nonexistent in the literature. Here we show that lake ANC is highly predictable (r2 = 0.75) based on the size of the exchangeable Ca2+ reservoir in soil in 21 catchments representative of soil and lake conditions encountered in northeastern North America. This finding indirectly supports the hypothesis that the poor recovery of surface water from acidification is governed by the size of base cation reservoirs present in catchment soils. The size of the base cation reservoir in soil is thus a strong indicator of the acid–base status of both soils and surface waters.

The long-term acid neutralizing capacity of steel slag

2000 ◽  
Vol 20 (2-3) ◽  
pp. 217-223 ◽  
Author(s):  
Jinying Yan ◽  
Luis Moreno ◽  
Ivars Neretnieks
Keyword(s):  
Steel Slag ◽  
Acid Neutralizing Capacity ◽  
Neutralizing Capacity

scholarly journals Winter climate affects long-term trends in stream water nitrate in acid-sensitive catchments in southern Norway

2007 ◽  
Vol 4 (5) ◽  
pp. 3055-3085 ◽  
Author(s):  
H. A. de Wit ◽  
A. Hindar ◽  
L. Hole
Keyword(s):  
Snow Depth ◽  
Stream Water ◽  
N Deposition ◽  
Climatic Changes ◽  
N Leaching ◽  
Forested Catchments ◽  
Discharge Temperature ◽  
Long Term Trends ◽  
Southern Norway

Abstract. Controls of stream water NO3 in mountainous and forested catchments are not thoroughly understood. Long-term trends in stream water NO3 are positive, neutral and negative, often apparently independent of trends in N deposition. Here, time series of NO3 in four small acid-sensitive catchments in southern Norway were analysed in order to identify likely drivers of long-term changes in NO3. In two sites, stream water NO3 export declined ca 50% over a period of 25 years while in the other sites NO3 export increased with roughly 20%. Discharge and N deposition alone were poor predictors of these trends. The most distinct trends in NO3 were found in winter and spring. Empirical models explained between 45% and 61% of the variation in weekly concentrations of NO3, and described both upward and downward seasonal trends tolerably well. Key explaining variables were snow depth, discharge, temperature and N deposition. All catchments showed reductions in snow depth and increases in winter discharge. In two inland catchments, located in moderate N deposition areas, these climatic changes appeared to drive the distinct decreases in winter and spring concentrations and fluxes of NO3. In a coast-near mountainous catchment in a low N deposition area, these climatic changes appeared to have the opposite effect, i.e. lead to increases in especially winter NO3. This suggests that the effect of a reduced snow pack may result in both decreased and increased catchment N leaching depending on interactions with N deposition, soil temperature regime and winter discharge.

scholarly journals Linking groundwater travel times to stream chemistry, isotopic composition and catchment characteristics

2020 ◽  
Author(s):  
Elin Jutebring Sterte ◽  
Fredrik Lidman ◽  
Emma Lindborg ◽  
Ylva Sjöberg ◽  
Hjalmar Laudon
Keyword(s):  
Travel Time ◽  
Stream Water ◽  
Base Cations ◽  
Base Cation ◽  
Isotopic Signature ◽  
Stream Chemistry ◽  
Travel Times ◽  
Underlying Assumption ◽  
Tracking Model

Abstract. Understanding travel times of rain and snowmelt inputs transported through the subsurface environment to recipient surface waters is critical in many hydrological and biogeochemical investigations. In this study, a particle tracking model approach in Mike SHE was used to investigating the travel time of stream groundwater input to 14 partly nested, long-term monitored boreal sub-catchments. Based on previous studies in the area, we hypothesized that the main factor controlling groundwater travel times was catchment size. The modeled mean travel time (MTT) in the different sub-catchments ranged between 0.5 years and 3.6 years. Estimated MTTs were tested against the observed long-term winter isotopic signature (δ2H, δ18O) and chemistry (base cation concentration and pH) of the stream water. The underlying assumption was that older water would have an isotopic signature that resembles the long-term average precipitation input, while seasonal variations would be more apparent in catchments with younger water. Similarly, it was assumed that older water would be more affected by weathering, resulting in higher concentrations of base cations and higher pH. 10-year average winter values for stream chemistry were used for each sub-catchment. We found significant correlations between the estimated travel times and average water isotope signature (r = 0.80, p 

scholarly journals Acid-neutralizing capacity of Finnish mineral soils

1985 ◽  
Vol 57 (4) ◽  
pp. 279-283
Author(s):  
Helinä Hartikainen
Keyword(s):  
Clay Soils ◽  
Acid Neutralizing Capacity ◽  
Significant Variable ◽  
Exchange Reactions ◽  
Organic C ◽  
Neutralizing Capacity ◽  
Heavy Clay ◽  
Mineral Soils ◽  
The Relationship ◽  
Soil Groups

The acid-neutralizing capacity (ANC) was determined graphically from curves obtained in HCI titration (at a constant ionic strength I = 0.1) and was expressed as a quantity of acid (meq kg-1) needed to reduce the soil pH to 3.8. The relationship between ANC3.8 g and soil characteristics was studied statistically. In 84 soil samples, ANC3.8 ranged from 12 to 184 meq kg-1. The average ANC3.8 was highest in the heavy clay soils and lowest in the non-clay soils, but the differences between the various textural soil groups were not significant. In all soil groups the initial pHCaCl2 was relatively the most important factor explaining the variation in ANC3.8. Organic C was also a significant variable; this was considered to indicate the importance of cation exchange reactions of organic matter in acid-buffering. With the exception of heavy clay soils, oxalate-soluble Al significantly explained the variation in ANC3.8, suggesting that dissolution of Al hydroxides acted as a sink for H+ ions and contributed to the neutralizing capacity at the reference pH of 3.8.

Sign in / Sign up

Export Citation Format

Share Document