Manganese and land-use in upland catchments in Scotland.

Manganese (Mn) in surface waters is a micronutrient, but elevated concentrations are toxic to fish and impair drinking water quality. In Scotland, undesirable Mn concentrations (> 0.05 mg l(-1)) occur predominantly in upland freshwaters because the acidic pH and organic nature of catchment soils favour Mn mobilisation. The relationship between upland land-use in Scotland and Mn concentrations in surface waters is reviewed. Conifer afforestation is associated with enhanced Mn in runoff. Mn is leached from conifer foliage and litter, and mature conifers enhance acid deposition and loss of Mn from acidified catchment soils. After harvesting, increased soil pools of water-soluble Mn and elevated Mn concentrations in runoff have been observed. Liming, fertiliser addition, drainage ditch construction and ploughing to improve upland pastures, and muirburn on grouse moors may also increase Mn concentrations in runoff, but the evidence is less clear-cut. The extent to which land-use influences Mn concentrations in upland catchments in Scotland is modified by catchment hydrology and soil type. Catchment geology, instream processes and standing water stratification are probably lesser influences on Mn concentrations in surface waters of upland catchments in Scotland. The location of land-use in upland catchments, especially in the riparian zone, is critical in determining its effect on Mn in runoff. Climate change is expected to increase Mn concentrations in runoff from upland catchments in Scotland because of predicted changes in soil hydrology.

[1]  R. B. Robinson,et al.  Committee Report -- Research Needs for the Treatment of Iron and Manganese (PDF) , 1987 .

[2]  J. Mccoll,et al.  Soluble organics from forest litter and their role in metal dissolution , 1988 .

[3]  William Davison,et al.  Iron and manganese in lakes , 1993 .

[4]  E. J. Wilson,et al.  The effectiveness of catchment liming in restoring acid waters at Loch Fleet, Galloway, Scotland , 1994 .

[5]  C. Ekin,et al.  Water Supply , 1911, Nature.

[6]  K. Nicholson,et al.  Manganese Mineralization: Geochemistry And Mineralogy of Terrestrial And Marine Deposits , 1996 .

[7]  W. A. Norvell Inorganic Reactions of Manganese in Soils , 1988 .

[8]  R. Baker Trace Inorganics In Water , 1968 .

[9]  E. Jenne Controls on Mn, Fe, Co, Ni, Cu, and Zn Concentrations in Soils and Water: the Significant Role of Hydrous Mn and Fe Oxides , 1968 .

[10]  D. Turnbull,et al.  Reversibility of stream acidification in the Cairngorm region of Scotland , 1997 .

[11]  G. Mitchell,et al.  Catchment Characterization as a Tool for Upland Water Quality Management , 1995 .

[12]  R. Graham,et al.  Manganese in Soils and Plants , 1988, Developments in Plant and Soil Sciences.

[13]  The synergism between SO2 oxidation and manganese leaching on spruce needles--a chamber experiment. , 1997, Environmental pollution.

[14]  B. Lazerte,et al.  Manganese speciation in dilute waters of the Precambrian shield, Canada , 1990 .

[15]  W. Broecker,et al.  Effects of Acidification on Mobilization of Heavy Metals and Radionuclides from the Sediments of a Freshwater Lake , 1980 .

[16]  R. Gilkes,et al.  Geochemistry and Mineralogy of Manganese in Soils , 1988 .

[17]  Y.-W. Brodin UK acid waters monitoring network: The first five years , 1996 .

[18]  Richard A. Skeffington,et al.  UK acid waters monitoring network: The first five years , 1997 .

[19]  A. T. Kuiters,et al.  Water-soluble organic matter in forest soils , 1993, Plant and Soil.

[20]  A. W. Damman Distribution and movement of elements in ombrotrophic peat , 1978 .

[21]  J. Shanley Manganese biogeochemistry in a small Adirondack forested lake watershed , 1986 .

[22]  H. Heinrichs,et al.  Distribution and cycling of major and trace elements in two central European forest ecosystems , 1977 .

[23]  G C COTZIAS,et al.  Manganese in health and disease. , 1958, Physiological reviews.

[24]  L. M. Shuman Effect of Liming on the Distribution of Manganese, Copper, Iron, and Zinc Among Soil Fractions1 , 1985 .

[25]  W. Mulder,et al.  Water-soluble organic matter in forest soils , 1993, Plant and Soil.

[26]  D. Kay,et al.  The effects of catchment land use on stream water quality in an acid-susceptible region of West Wales: the implications for compliance with EC drinking water and fishery directives , 1988 .

[27]  M. Hodgkinson,et al.  Deposition of manganese in a drinking water distribution system , 1990, Applied and environmental microbiology.

[28]  B. Cosby,et al.  A dynamic model for assessing the impact of coupled sulphur and nitrogen deposition scenarios on surface water acidification , 1997 .

[29]  M. Cresser,et al.  An assessment of the possible impact of expansion of native woodland cover on the chemistry of Scottish freshwaters , 1995 .

[30]  P. Maitland,et al.  The fresh waters of Scotland: a national resource of international significance. , 1995 .

[31]  K. Nicholson,et al.  Geochemistry of manganese oxides: metal adsorption in freshwater and marine environments , 1997, Geological Society, London, Special Publications.

[32]  M. Hill,et al.  Nutrient Accumulation in Vegetation Following Conventional and Whole-Tree Harvest of Sitka Spruce Plantations in North Wales , 1991 .

[33]  C. Neal,et al.  Forestry Impact on Upland Water Quality , 1992 .

[34]  P. R. Whitney Heavy metals and manganese oxides in the genesee watershed, New York state: effects of geology and land use , 1981 .

[35]  T. Schofield,et al.  Frankley Water‐Treatment Works Redevelopment: Pilot‐Scale Studies , 1991 .

[36]  S. Jarvis The forms of occurrence of manganese in some acidic soils , 1984 .

[37]  E. Degerman,et al.  Labile inorganic manganese — An overlooked reason for fish mortality in acidified streams? , 1995 .

[38]  Konrad B. Krauskopf,et al.  Introduction to geochemistry , 1967 .

[39]  Timothy J. Fahey,et al.  Decomposition and Nutrient Release from Logging Residue Following Conventional Harvest of Sitka Spruce in North Wales , 1991 .

[40]  C. Neal,et al.  Major, minor and trace element mobility in the acidic upland forested catchment of the upper River Severn, Mid Wales , 1986, Journal of the Geological Society.

[41]  D. Macleod,et al.  Factors affecting the chemistry of precipitation and river water in an upland catchment , 1981 .

[42]  M. Zaw,et al.  Lake destratification and speciation of iron and manganese , 1991, Environmental monitoring and assessment.

[43]  W. Davison,et al.  Manganese chemistry in rivers and streams , 1984 .