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Nutrient relations and root mycorrhizal status of healthy and declining beech (Fagus sylvatica L.) in southern Britain
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Selected Bibliography
Aerial photographs from 1970 and 1989 were used to assess the recovery of approximately 100 000 ha of smelter-damaged lands near Sudbury, Canada. Recent improvements in air quality enabled conifers to recolonize about 22% of the 'semibarrens', an area that consisted of a newer monoculture of coppiced and stunted white birch (Betula papyrifera). The more heavily damaged 'barren' areas, surrounding the three smelter sites, exhibited very little natural recovery during the study period. A municipal land reclamation program was responsible for most of the observed revegetation within the barren area. Between 1978 and 1988 approximately 2000 ha of barrens were reclaimed through soil treatment, grassing and tree planting. An estimated 7400 ha of the most heavily damaged land is still in need of immediate remedial treatment. Increased rates of natural recovery are expected in the future as SO2 emissions are reduced. Continued municipal and expanded industrial reclamation programs in the 1990s will also greatly reduce the extent of bare land.
Enhanced growth of the macrophyte Juncus bulbosus in S. Norwegian limed lakes. A regional survey. Brandrud T. E. and Roelofs J. G. M. Norwegian Institute for Water Research, PO Box 173, 0411 Kjelsas, Oslo, Norway. Water Air Soil Pollut., 1995, 85/2 (913-918). Summ. in Engl. The effects of liming on the aquatic macrophyte vegetation have been investigated in south and southwest Norway. In the western part of the study area, Juncus bulbosus was considerably more frequent in the limed than in the unlimed lakes, whilst in the eastern part there were no such differences, and the J. bulbosus populations were generally not so vital. In some southwestern areas a luxuriant and massive nuisance growth of Juncus bulbosus in the depth zone 0--4 m was recorded. The most vital plants produced up to 1 m long annual shoots, and developed extensive, dense and vital surface mats in shallow areas (depth zone 0-3 m) after 4-5 years. The original isoetid vegetation had disappearead in the areas of dense J. bulbosus populations, and this development seems to be more or less reversible. The massive J. bulbosus expansion is seen mainly in directly limed lakes with a sometimes visible layer of calcium carbonate on the sediment surface, but enhanced growth has been observed also in lakes downstream of liming. The massive expansion is believed to be due to to an increase of CO2 and ammonium in the sediment pore water, combined with a mild climate with a very high precipitation. In many areas the liming has led to an increase in species diversity, and a (re-)establishment of some acid-intolerant species such as Myriophyllum alterniflorum and Potamogeton spp.
Nutrient relations and root mycorrhizni status of healthy and declining beech (Fagus sylvatica L.) in southern Britain. Power S. A. and Ashmore M. R. Imperial College, Silwood Park, Ascot, Berkshire, SL5 7PY, UK. Water Air Soil Pollut., 1996, 86/1-4 (317-333). Summ. in Engl. Many studies have been carried out to investigate the wide scale problem of forest decline that is affecting vast numbers of trees throughout Europe and North America. Evidence of nutritional disturbances, both above- and below-ground, has been found for a variety of species. Furthermore it has been suggested that differences in above-ground tree health are often reflected below ground, particularly in the root systems of declining trees. An investigation of root vitality, soil and leaf chemistry of healthy and unhealthy beech (Fagus sylvatica L.) was carried out at a number of sites in southern
Britain, covering a wide range of different soil types. At each site, healthy and unhealthy trees growing in very close proximity were compared in order to avoid large scale environmental differences that might be expected when comparing stands of trees at different locations. Healthy trees were found to have significantly greater proportions of live mycorrhizal roots than their unhealthy neighbours at most of the sites investigated. In addition, significant differences in soil chemistry were found between trees in contrasting health, with healthy trees generally growing in soil containing higher concentrations of calcium, magnesium and potassium and lower aluminiurn/calcium ratios. Very few differences were found in leaf nutrient content, suggesting that soil chemistry is not yet limiting nutrient uptake. The importance of root system differences in the tolerance of unfavourable edaphic and climatic conditions is discussed with respect to tree health.
Biological recovery of two previously acidified, metal contaminated lakes near Sudbary, Ontario, Canada. Havas M., Woodfine D. G. and Lutz P. et al. Environmental and Resource Studies, Trent University, Peterborough, Ontario, K9J 7B8, Canada. Water Air Soil Pollut., 1995, 85/2 (791/796). Summ. in Engl. Studies are reported on two small lakes at Sudbury, Ontario located close to a nickel-copper smelter which closed in 1972. At that stage, Baby Lake had a pH of 4.0--4.2 while the adjacent Alice Lake had a pH 5.9--6.3. Both lakes were almost entirely devoid of algae and had neither zooplankton nor fish. Soon after the closure of the smelter, with its large airborne volume of sulphur dioxide and of copper and nickel containing particles, the chemistry of the lakes began to change. By 1985, Baby Lake had changed from pH 4.0 to 6.8 and is now at pH 7.2. The pH of Alice Lake increased from a low of 5.9 in the early 1970s to 6.9-7.4 in the mid 1980s and is now at 7.3. Copper and nickel concentrations also decreased in both lakes during this period. The first biota found in the lakes in the post-smelter stage in the early 1980s were benthic red chironomids, planktonic rotifers, and a limited number of phytoplankton species, of which Rhizosolenia was the most common. By the 1990s, 13 phytoplankton species were present in each lake, with a substantial zooplankton fauna (14 species) of rotifers, copepods, and cladocerans. There are now numerous insect larvae in the sediment and some small fish in both lakes. The biological recovery, which followed substantial reductions in acidity and in soluble nickel and copper concentrations in the waters, is a slower process than chemical recovery and is initially characterized by the dominance of a few species. In situ monitoring of dredged material spoil sites using the oyster Crassostrea virginica. Wirth E. F., Scott G. I. and
Fulton M. H. et al. National Oceanic and Atmospheric Administration, National Marine Fisheries Service, Southeast Fisheries Science Center, PO Box 12607, Charleston, SC 29422, USA. Arch. Environ. Contain. Toxicol., 1996, 30/3 (340-348). Summ. in Engl.
In situ and laboratory bioassays using the eastern oyster, Crassostrea virginica, were undertaken in the Wright River Estuary, South Carolina, to determine the toxic potential of effluent and sediment from recently dredged sediments. Current standards (ASTM, USEPA, and USACE) rely solely on laboratory-based bioassays to assess toxicity of dredge spoils prior to disposal. These bioassays do not necessarily replicate the natural physicocbemical estuarine processes, limiting the environmental realism of this approach. In the
Selected Bibliography
Aerial photographs from 1970 and 1989 were used to assess the recovery of approximately 100 000 ha of smelter-damaged lands near Sudbury, Canada. Recent improvements in air quality enabled conifers to recolonize about 22% of the 'semibarrens', an area that consisted of a newer monoculture of coppiced and stunted white birch (Betula papyrifera). The more heavily damaged 'barren' areas, surrounding the three smelter sites, exhibited very little natural recovery during the study period. A municipal land reclamation program was responsible for most of the observed revegetation within the barren area. Between 1978 and 1988 approximately 2000 ha of barrens were reclaimed through soil treatment, grassing and tree planting. An estimated 7400 ha of the most heavily damaged land is still in need of immediate remedial treatment. Increased rates of natural recovery are expected in the future as SO2 emissions are reduced. Continued municipal and expanded industrial reclamation programs in the 1990s will also greatly reduce the extent of bare land.
Enhanced growth of the macrophyte Juncus bulbosus in S. Norwegian limed lakes. A regional survey. Brandrud T. E. and Roelofs J. G. M. Norwegian Institute for Water Research, PO Box 173, 0411 Kjelsas, Oslo, Norway. Water Air Soil Pollut., 1995, 85/2 (913-918). Summ. in Engl. The effects of liming on the aquatic macrophyte vegetation have been investigated in south and southwest Norway. In the western part of the study area, Juncus bulbosus was considerably more frequent in the limed than in the unlimed lakes, whilst in the eastern part there were no such differences, and the J. bulbosus populations were generally not so vital. In some southwestern areas a luxuriant and massive nuisance growth of Juncus bulbosus in the depth zone 0--4 m was recorded. The most vital plants produced up to 1 m long annual shoots, and developed extensive, dense and vital surface mats in shallow areas (depth zone 0-3 m) after 4-5 years. The original isoetid vegetation had disappearead in the areas of dense J. bulbosus populations, and this development seems to be more or less reversible. The massive J. bulbosus expansion is seen mainly in directly limed lakes with a sometimes visible layer of calcium carbonate on the sediment surface, but enhanced growth has been observed also in lakes downstream of liming. The massive expansion is believed to be due to to an increase of CO2 and ammonium in the sediment pore water, combined with a mild climate with a very high precipitation. In many areas the liming has led to an increase in species diversity, and a (re-)establishment of some acid-intolerant species such as Myriophyllum alterniflorum and Potamogeton spp.
Nutrient relations and root mycorrhizni status of healthy and declining beech (Fagus sylvatica L.) in southern Britain. Power S. A. and Ashmore M. R. Imperial College, Silwood Park, Ascot, Berkshire, SL5 7PY, UK. Water Air Soil Pollut., 1996, 86/1-4 (317-333). Summ. in Engl. Many studies have been carried out to investigate the wide scale problem of forest decline that is affecting vast numbers of trees throughout Europe and North America. Evidence of nutritional disturbances, both above- and below-ground, has been found for a variety of species. Furthermore it has been suggested that differences in above-ground tree health are often reflected below ground, particularly in the root systems of declining trees. An investigation of root vitality, soil and leaf chemistry of healthy and unhealthy beech (Fagus sylvatica L.) was carried out at a number of sites in southern
Britain, covering a wide range of different soil types. At each site, healthy and unhealthy trees growing in very close proximity were compared in order to avoid large scale environmental differences that might be expected when comparing stands of trees at different locations. Healthy trees were found to have significantly greater proportions of live mycorrhizal roots than their unhealthy neighbours at most of the sites investigated. In addition, significant differences in soil chemistry were found between trees in contrasting health, with healthy trees generally growing in soil containing higher concentrations of calcium, magnesium and potassium and lower aluminiurn/calcium ratios. Very few differences were found in leaf nutrient content, suggesting that soil chemistry is not yet limiting nutrient uptake. The importance of root system differences in the tolerance of unfavourable edaphic and climatic conditions is discussed with respect to tree health.
Biological recovery of two previously acidified, metal contaminated lakes near Sudbary, Ontario, Canada. Havas M., Woodfine D. G. and Lutz P. et al. Environmental and Resource Studies, Trent University, Peterborough, Ontario, K9J 7B8, Canada. Water Air Soil Pollut., 1995, 85/2 (791/796). Summ. in Engl. Studies are reported on two small lakes at Sudbury, Ontario located close to a nickel-copper smelter which closed in 1972. At that stage, Baby Lake had a pH of 4.0--4.2 while the adjacent Alice Lake had a pH 5.9--6.3. Both lakes were almost entirely devoid of algae and had neither zooplankton nor fish. Soon after the closure of the smelter, with its large airborne volume of sulphur dioxide and of copper and nickel containing particles, the chemistry of the lakes began to change. By 1985, Baby Lake had changed from pH 4.0 to 6.8 and is now at pH 7.2. The pH of Alice Lake increased from a low of 5.9 in the early 1970s to 6.9-7.4 in the mid 1980s and is now at 7.3. Copper and nickel concentrations also decreased in both lakes during this period. The first biota found in the lakes in the post-smelter stage in the early 1980s were benthic red chironomids, planktonic rotifers, and a limited number of phytoplankton species, of which Rhizosolenia was the most common. By the 1990s, 13 phytoplankton species were present in each lake, with a substantial zooplankton fauna (14 species) of rotifers, copepods, and cladocerans. There are now numerous insect larvae in the sediment and some small fish in both lakes. The biological recovery, which followed substantial reductions in acidity and in soluble nickel and copper concentrations in the waters, is a slower process than chemical recovery and is initially characterized by the dominance of a few species. In situ monitoring of dredged material spoil sites using the oyster Crassostrea virginica. Wirth E. F., Scott G. I. and
Fulton M. H. et al. National Oceanic and Atmospheric Administration, National Marine Fisheries Service, Southeast Fisheries Science Center, PO Box 12607, Charleston, SC 29422, USA. Arch. Environ. Contain. Toxicol., 1996, 30/3 (340-348). Summ. in Engl.
In situ and laboratory bioassays using the eastern oyster, Crassostrea virginica, were undertaken in the Wright River Estuary, South Carolina, to determine the toxic potential of effluent and sediment from recently dredged sediments. Current standards (ASTM, USEPA, and USACE) rely solely on laboratory-based bioassays to assess toxicity of dredge spoils prior to disposal. These bioassays do not necessarily replicate the natural physicocbemical estuarine processes, limiting the environmental realism of this approach. In the