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Analysis of tree rings using inductively coupled plasma mass spectrometry to record fluctuations in a metal pollution episode
1996
Watmough, S.A. | Hutchinson, T.C. (Environmental and Resource Studies Program, Trent University, Peterborough, Ontario K9J 7B8, Canada)
Change in the dendrochemistry of sacred fir close to Mexico City over the past 100 years
1999
Watmough, S.A. | Hutchinson, T.C. (ERS Program, Trent University, Peterborough, Ontario K9J 7B8 (Canada))
Changes in tree ring chemistry in sugar maple (Acer saccharum) along an urban-rural gradient in southern Ontario
1998
Watmough, S.A. | Hutchinson, T.C. | Sager, E.P.S. (Environmental Resource Studies Program, Trent University, Peterborough, Ontario, K9J 7B8 (Canada))
The Tree-Ring Method of Estimation of the Effect of Industrial Pollution on Pine (Pinus sylvestris L.) Tree Stands in the Northern Part of the Sandomierz Basin (SE Poland)
2016
Barniak, Joanna | Krąpiec, Marek
In the last 40 years of the twentieth century, as a result of the growth in the exploitation and industrial processing of sulphur, the northern part of the Sandomierz Basin was one of the most polluted areas of Poland. Forests growing in this region, predominantly the Scots pine, offered an opportunity to analyse the degradation of the environment during that period using the dendrochronological method. The study was based on 814 samples, taken from 53 research surfaces belonging to nine linear transects. The investigations demonstrated that the highest reduction in growth occurred during the years 1970–1990. After that period, a considerable improvement in the condition of the pine trees was observed in most of the research plots. The spatial schedule of the trees with reductions reveals a clear relationship with the distance from the emitter i.e. the reductions were significantly lower in more distant sites. A distinct weakening of the trees is also indicated by missing rings, recorded in the years: 1964, 1974, 1978, 1979, 1980, 1985, 1990, and 2002. A definite impact on the condition of the tree stands was also due to the cone of depression around the Jeziórko mine, the post-flotation landfills, as well as pollution on a regional scale.
Afficher plus [+] Moins [-]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.
Afficher plus [+] Moins [-]The Influence of Industry on Scots Pine Stands in the South-eastern Part of the Silesia-Krakow Upland (Poland) on the Basis of Dendrochronological Analysis
2007
Danek, Małgorzata
Air pollution is considered a key stress factor affecting the annual ring widths of the trees, especially living in industrialized areas. The Silesia-Krakow Upland is one of the most polluted areas in Poland. Scots pine stands living there have been under influence of air pollution for a long period of time. Dendrochronological analysis in five separated transects, which were performed in this region, showed the abrupt and usually long term reductions observed in radial increments of sampled pines. The abrupt increase of reductions started in the beginning of 1960s. Most of them occurred in the years 1960-1990, after this period the number of Scots pine trees with reduced annual increments decreased considerably. The distribution of reductions in particular sites, especially of the Olkusz transects, indicate a distinct relationship between the amount of reductions and distance from local source of pollution. On the other hand the similarity in temporal distribution of reductions in all transects indicate that the studied area was probably also under influence of air pollution of a regional type.
Afficher plus [+] Moins [-]Growth responses of Scots pine to climatic factors on reclaimed oil shale mined land
2016
Metslaid, Sandra | Stanturf, John A. | Hordo, Maris | Korjus, Henn | Laarmann, Diana | Kiviste, Andres
Afforestation on reclaimed mining areas has high ecological and economic importance. However, ecosystems established on post-mining substrate can become vulnerable due to climate variability. We used tree-ring data and dendrochronological techniques to study the relationship between climate variables and annual growth of Scots pine (Pinus sylvestris L.) growing on reclaimed open cast oil shale mining areas in Northeast Estonia. Chronologies for trees of different age classes (50, 40, 30) were developed. Pearson’s correlation analysis between radial growth indices and monthly climate variables revealed that precipitation in June–July and higher mean temperatures in spring season enhanced radial growth of pine plantations, while higher than average temperatures in summer months inhibited wood production. Sensitivity of radial increment to climatic factors on post-mining soils was not homogenous among the studied populations. Older trees growing on more developed soils were more sensitive to precipitation deficit in summer, while growth indices of two other stand groups (young and middle-aged) were highly correlated to temperature. High mean temperatures in August were negatively related to annual wood production in all trees, while trees in the youngest stands benefited from warmer temperatures in January. As a response to thinning, mean annual basal area increment increased up to 50 %. By managing tree competition in the closed-canopy stands, through the thinning activities, tree sensitivity and response to climate could be manipulated.
Afficher plus [+] Moins [-]Air pollution effects on vegetation including forest ecosystems
1989
Noble, Reginald D. | Martin, Juri L. | Jensen, Keith F.