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- Karlsson, Per Erik, 1957, et al.
(author)
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A cumulative ozone uptake-response relationship for the growth of Norway spruce saplings
- 2004
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In: Environmental Pollution. - : Elsevier BV. - 0269-7491. ; 128:3, s. 405-417
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Journal article (peer-reviewed)abstract
- Norway spruce saplings [Picea abies (L.) Karst.] were exposed during four growing seasons to different ozone treatments in open-top chambers: charcoal filtered air (CF), non-filtered air (NF) and non-filtered air with extra ozone (NF+, 1.4xambient concentrations). The CF and NF + ozone treatments were combined with phosphorous deficiency and drought stress treatments. The total biomass of the trees was harvested at different intervals during the experimental period. The ozone uptake to current-year needles of the Norway spruce saplings was estimated using a multiplicative stomatal conductance simulation model. There was a highly significant correlation between the reduction of total biomass and the estimated cumulative ozone uptake, which did not vary when different thresholds were applied for the rate of ozone uptake. The reduction of the total biomass was estimated to 1 per 10 mmol m(-2) cumulated ozone uptake, on a projected needle area basis. (C) 2003 Elsevier Ltd. All rights reserved.
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| 2. |
- Karlsson, Per Erik, 1957, et al.
(author)
-
Impact of ozone on the growth of birch (Betula pendula) saplings
- 2003
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In: Environmental Pollution. - 0269-7491. ; 124:3, s. 485-495
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Journal article (peer-reviewed)abstract
- Saplings of one half-sib family of birch, Betula pendula, were exposed to three levels of ozone in open-top chambers (OTCs) during two growing seasons 1997-1998. The ozone treatments were non-filtered air (NF, accumulated daylight AOT40 over the two growing seasons of 3.0 mul l(-1) h), non-filtered air with extra ozone (NF +, accumulated daylight AOT40 of 27.3 mul l(-1) h) and nonfiltered air with additional extra ozone (NF++, accumulated daylight AOT40 of 120 mul l(-1) h), The birch saplings, including the roots, were harvested after the first and second growing seasons. After the first growing season, the NF++ treatment reduced the total wood biomass by 22%, relative to the NF treatment. There was no further reduction of the total wood biomass in the NF++ treatment after the second growing season. The root biomass was reduced by 30% after the first growing season. The shoot/root ratio, as well as the proportional biomass of leaves, were increased by ozone during both years. The ozone impact on the relative growth rate was estimated to -2% per 10 mul l(-1) h daylight AOT40 per growing season. (C) 2003 Elsevier Science Ltd. All rights reserved.
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