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- W2070067236 abstract "The concept of critical levels was developed in order to define short-term and long-term average concentrations of gaseous pollutants above which plants may be damaged. Although the usual way in which pollutants in precipitation (wet deposition) influence vegetation is by affecting soil processes, plant foliage exposed to fog and cloud, which often contain much greater concentrations of pollutant ions than rain, may be damaged directly. The idea of a critical level has been extended to define concentrations of pollutants in wet deposition above which direct damage to plants is likely. Concentrations of acidity and sulphate measured in mountain and coastal cloud are summarised. Vegetation at risk of injury is identified as montane forest growing close to the cloud base, where ion concentrations are highest. The direct effects of acidic precipitation on trees are reviewed, based on experimental exposure of plants to simulated acidic rain, fog or mist. Although most experiments have reported results in terms of pH (H(+) concentration), the accompanying anion is important, with sulphate being more damaging than nitrate. Both conifers and broadleaved tree seedlings showing subtle changes in the structural characteristics of leaf surfaces after exposure to mist or rain at or about pH 3.5, or sulphate concentration of 150 micromol litre(-1). Visible lesions on leaf surfaces occur at around pH 3 (500 micromol litre(-1) sulphate), broadleaved species tending to be more sensitive than conifers. Effects on photosynthesis and water relations, and interactions with other stresses (e.g. frost), have usually been observed only for treatments which have also caused visible injury to the leaf surface. Few experiments on the direct effects of polluted cloud have been conducted under field conditions with mature trees, which unlike seedlings in controlled conditions, may suffer a growth reduction in the absence of visible injury. Although leaching of cations (Ca(2+), Mg(2+), K(+)) is stimulated by acidic precipitation, amounts leached are small compared with root uptake, unless soils have been impoverished. This aspect of the potential effects of acidic precipitation is best considered in terms of the long-term critical-load of pollutants to the soil. Given the practical difficulties in monitoring cloud water composition, a method for defining critical levels is proposed, which uses climatological average data to identify the duration and frequency of hill cloud, and combines this information with measured or modelled concentrations of particulate sulphate in the atmosphere, to derive cloud water concentrations as a function of cloud liquid water content. For forests within 100 m of the cloud base the critical levels of particulate sulphate, corresponding to solution concentrations in the range 150-500 micromol litre(-1), are in the range 1-3.3 microg S m(-3). These concentrations are observed over much of central Europe, suggesting that many montane forests are at risk of direct effects of fossil-fuel-derived pollutants in cloud." @default.
- W2070067236 created "2016-06-24" @default.
- W2070067236 creator A5023028117 @default.
- W2070067236 date "1993-01-01" @default.
- W2070067236 modified "2023-09-23" @default.
- W2070067236 title "Direct damage to vegetation caused by acid rain and polluted cloud: Definition of critical levels for forest trees" @default.
- W2070067236 cites W1659014837 @default.
- W2070067236 cites W1966859552 @default.
- W2070067236 cites W1967492470 @default.
- W2070067236 cites W1968358148 @default.
- W2070067236 cites W1968918329 @default.
- W2070067236 cites W1970679606 @default.
- W2070067236 cites W1972640726 @default.
- W2070067236 cites W1975759725 @default.
- W2070067236 cites W1981942665 @default.
- W2070067236 cites W1983250255 @default.
- W2070067236 cites W1984745775 @default.
- W2070067236 cites W1985044810 @default.
- W2070067236 cites W1985510267 @default.
- W2070067236 cites W1987939008 @default.
- W2070067236 cites W1991312936 @default.
- W2070067236 cites W1992193376 @default.
- W2070067236 cites W1997388014 @default.
- W2070067236 cites W1998601912 @default.
- W2070067236 cites W1999780399 @default.
- W2070067236 cites W2001760287 @default.
- W2070067236 cites W2002908502 @default.
- W2070067236 cites W2004963172 @default.
- W2070067236 cites W2007234105 @default.
- W2070067236 cites W2014019981 @default.
- W2070067236 cites W2017077959 @default.
- W2070067236 cites W2017449071 @default.
- W2070067236 cites W2022951491 @default.
- W2070067236 cites W2024284764 @default.
- W2070067236 cites W2026080094 @default.
- W2070067236 cites W2029034307 @default.
- W2070067236 cites W2030229931 @default.
- W2070067236 cites W2032178553 @default.
- W2070067236 cites W2033143306 @default.
- W2070067236 cites W2036389311 @default.
- W2070067236 cites W2042258569 @default.
- W2070067236 cites W2044273220 @default.
- W2070067236 cites W2045376831 @default.
- W2070067236 cites W2047178014 @default.
- W2070067236 cites W2047499133 @default.
- W2070067236 cites W2048428847 @default.
- W2070067236 cites W2051465941 @default.
- W2070067236 cites W2052665336 @default.
- W2070067236 cites W2054369096 @default.
- W2070067236 cites W2058273973 @default.
- W2070067236 cites W2062074620 @default.
- W2070067236 cites W2068742039 @default.
- W2070067236 cites W2072947622 @default.
- W2070067236 cites W2075195750 @default.
- W2070067236 cites W2075414981 @default.
- W2070067236 cites W2075519421 @default.
- W2070067236 cites W2075779949 @default.
- W2070067236 cites W2077494848 @default.
- W2070067236 cites W2077574752 @default.
- W2070067236 cites W2077842605 @default.
- W2070067236 cites W2078079292 @default.
- W2070067236 cites W2078565780 @default.
- W2070067236 cites W2080831029 @default.
- W2070067236 cites W2081292700 @default.
- W2070067236 cites W2082292851 @default.
- W2070067236 cites W2082783822 @default.
- W2070067236 cites W2093681515 @default.
- W2070067236 cites W2099775388 @default.
- W2070067236 cites W2111928162 @default.
- W2070067236 cites W2112950389 @default.
- W2070067236 cites W2137318947 @default.
- W2070067236 cites W2137690785 @default.
- W2070067236 cites W2138680532 @default.
- W2070067236 cites W2139609065 @default.
- W2070067236 cites W2140750314 @default.
- W2070067236 cites W2141995249 @default.
- W2070067236 cites W2152415173 @default.
- W2070067236 cites W2158420671 @default.
- W2070067236 cites W2208041764 @default.
- W2070067236 cites W2399235644 @default.
- W2070067236 cites W2480729330 @default.
- W2070067236 cites W2766869861 @default.
- W2070067236 cites W289623012 @default.
- W2070067236 cites W3022602741 @default.
- W2070067236 cites W4232999418 @default.
- W2070067236 cites W4233462804 @default.
- W2070067236 cites W4236439030 @default.
- W2070067236 cites W4237886313 @default.
- W2070067236 cites W4240282013 @default.
- W2070067236 cites W428378828 @default.
- W2070067236 cites W469172067 @default.
- W2070067236 cites W65004010 @default.
- W2070067236 cites W1989043129 @default.
- W2070067236 doi "https://doi.org/10.1016/0269-7491(93)90114-4" @default.
- W2070067236 hasPubMedId "https://pubmed.ncbi.nlm.nih.gov/15091786" @default.
- W2070067236 hasPublicationYear "1993" @default.
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