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Changes in phytomass and nutrient partitioning in young conifers in extreme alkaline growth conditions
1999
Mandre, M. | Kloseiko, J. | Ots, K. | Tuulmets, L. (Estonian Agricultural University, Forest Research Institute, Department of Ecophysiology, Viljandi mnt.18b, Tallinn 11216 (Estonia))
Genetic Analysis of Black Spruce (Picea mariana) Populations from Dry and Wet Areas of a Metal-Contaminated Region in Ontario (Canada)
2011
Dobrzeniecka, Sylwia | Nkongolo, Kabwe K. | Michael, Paul | Mehes-Smith, Melanie | Beckett, Peter
Genetic variation and genetic structure of black spruce (Picea mariana L.) populations growing in wet land (lowlands) and dry lands (uplands) with different levels of metal contaminations were analyzed using ISSR. Polymorphic loci (P%) ranged from 65% to 90% with a mean of 75%. Nei’s gene diversity (h) varied from 0.264 to 0.359 with a mean of 0.310, and Shannon’s index (I) ranged from 0.381 to 0.524 with a mean of 0.449. The level of genetic variation was higher in populations from wet lands than those from dry lands. Variation within populations accounts for most of total genetic variation. The genetic distance among the black spruce (P. mariana) populations ranged from 0.171 to 0.351. The present study indicates that genetic variation and long-term exposure to metals (more than 30Â years) are not associated. Cytological analysis of black spruce seeds from metal-contaminated and -uncontaminated areas showed normal mitotic behavior during prophase, metaphase, anaphase, and telophase.
显示更多 [+] 显示较少 [-]Lead Exclusion and Copper Translocation in Black Spruce Needles
2009
Aznar, J.-C. | Richer-Laflèche, M. | Bégin, C. | Bégin, Y.
Current-year, 1-year-old, and 2-year-old needles were collected separately on 37 black spruce (Picea mariana Mill. B.S.P.) trees located on a heavy metal contamination gradient around the smelter in Murdochville, Québec (Canada). Needles were analyzed separately by year for the concentrations of Pb and Cu, a nonessential and an essential metal, respectively. Lead concentrations increased significantly with needle age in the highly contaminated area near the smelter. In contrast, Cu concentrations decreased with needle age in the same area. Our results support the hypothesis that the passive sequestration of toxic metals in the senescing foliage is a detoxification process contrasting with the active translocation of essential metals in the nonsenescent part of the foliage.
显示更多 [+] 显示较少 [-]Mining and Smelting Activities Produce Anomalies in Tree-growth Patterns (Murdochville, Québec)
2007
Aznar, J.-C. | Richer-Laflèche, M. | Bégin, C. | Marion, J.
At 94 sites throughout the Gaspésie peninsula, Québec, tree growth patterns and variation in growth rate were examined to determine relationship of tree growth to specific pollutants. Canopy dominant Black Spruce (Picea mariana, (Mill.) BSP) were selected at each site. Basal area increment (BAI) values were derived from increment cores and disks taken at breast height. A sigmoid model (Gompertz) to tree basal area was fitted and used as an estimate of tree growth. The residuals were used in association with other landscape variables to test the hypothesis that the tree-growth was reduced at the vicinity of the Murdochville smelter. Results showed that residuals were well explained by smelter distance, elevation, and slope exposition to the smelter emissions. On the intense activity period, tree growth was reduced within a 25-km radius of the smelter, on slopes exposed to the contaminant flow and located at elevation lower than 580 m. With the interruption of smelting activities, growth was recovered for survival trees.
显示更多 [+] 显示较少 [-]Analyzing tree cores to detect petroleum hydrocarbon-contaminated groundwater at a former landfill site in the community of Happy Valley-Goose Bay, eastern Canadian subarctic
2016
Fonkwe, Merline L. D. | Trapp, Stefan
This research examines the feasibility of analyzing tree cores to detect benzene, toluene, ethylbenzene, and m, p, o-xylene (BTEX) compounds and methyl tertiary-butyl ether (MTBE) in groundwater in eastern Canada subarctic environments, using a former landfill site in the remote community of Happy Valley-Goose Bay, Labrador. Petroleum hydrocarbon contamination at the landfill site is the result of environmentally unsound pre-1990s disposal of households and industrial solid wastes. Tree cores were taken from trembling aspen, black spruce, and white birch and analyzed by headspace-gas chromatography-mass spectrometry. BTEX compounds were detected in tree cores, corroborating known groundwater contamination. A zone of anomalously high concentrations of total BTEX constituents was identified and recommended for monitoring by groundwater wells. Tree cores collected outside the landfill site at a local control area suggest the migration of contaminants off-site. Tree species exhibit different concentrations of BTEX constituents, indicating selective uptake and accumulation. Toluene in wood exhibited the highest concentrations, which may also be due to endogenous production. Meanwhile, MTBE was not found in the tree cores and is considered to be absent in the groundwater. The results demonstrate that tree-core analysis can be useful for detecting anomalous concentrations of petroleum hydrocarbons, such as BTEX compounds, in subarctic sites with shallow unconfined aquifers and permeable soils. This method can therefore aid in the proper management of contamination during landfill operations and after site closures.
显示更多 [+] 显示较少 [-]Distribution of aluminum in black spruce saplings growing on two New Brunswick forest soils with contrasting acid sulfate sorption
1989
Arp, P.A. (New Brunswick Univ., Fredericton, N.B. (Canada). Faculty of Forestry) | Akerley, C. | Mellerowicz, K.
Uptake of Al, Ca and P in black spruce seedlings: effect of organic versus inorganic Al in nutrient solutions
1986
Arp, P.A. (New Brunswick Univ., Fredericton (Canada)) | Ouimet, R.
Water uptake by black spruce seedlings from rooting media (solution, sand, peat) treated with inorganic and oxalated aluminum
1989
Arp, P.A. (New Brunswick Univ., Fredericton (Canada). Faculty of Forestry) | Strucel, I.
Al uptake by black spruce seedlings: persistence of organic acids in Al treated rooting cultures
1989
Arp, P.A. (New Brunswick Univ., Fredericton (Canada). Dept. of Forest Resources) | D'Avignon, H.
Black spruce in the industrial area North-East Estonia
2000
Mandre, M. (Estonian Agricultural Univ., Tartu (Estonia). Forest Research Inst.)
The present paper is based on experiments carried out with black spruce in the industrial area North-East Estonia. Two-year-old seedlings of black spruce were planted in a sample plot affected by a cement plant and by oil-shale processing enterprises and in an unpolluted control sample plot in 1990. At the end of the experiment in 1997 it was ascertained that the impact of industrial alkaline air pollution complexes resulting in the alkalisation and chemical deviations of growth conditions retards the height growth of trees and brings about a decrease in their biomass. The sturdiness quotient was higher and the Dickson quality index was lower than the control, indicating serious damages of trees under air pollution. Increasing share of needles in the total biomass in polluted areas in comparison with control trees suggest that compensation mechanism were started in trees to increase the assimilating mass in order to survive under stress. The state of young black spruces in alkalised industrial areas shows unsuitability of using this species in industrial areas
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