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Representation of the seasonal hydrological cycle in climate and weather prediction models in West Europe
2000
Dolman, A.J.
Patterns of low-frequency climate variability: a model-paleodata comparison
2000
Weber, S.L. | Shabalova, M.V.
Air pollution and the forests of developing and rapidly industrializing regions
2000
Innes, John L. | Haron, A. H (Abu Hassan)
This text examines the importance of air pollution for the forests of rapidly industrializing countries and regions. The problems presented by air pollution are placed within the more general context of sustainable development and the historical legacy that they are attempting to deal with.
Afficher plus [+] Moins [-]Air pollution and the forests of developing and rapidly industrializing regions Texte intégral
2000
Innes, John L. | Haron, A. H (Abu Hassan)
This book examines the importance of air pollution for the forests of rapidly industrializing countries and regions in 12 main chapters contributed by different authors. Its geographical coverage includes South and Central America, Africa and Asia, including Siberia, China and Korea. The problems presented by air pollution are placed within the more general context of sustainable development within these regions and the historical legacy that they are attempting to deal with. Attention is drawn to the very serious problems associated with poor air quality in cities such as Mexico City and Chongqing, China. Air pollution in these areas is amongst the worst in the world. Several chapters examine the importance of forest fires as a source of air pollution, with particular reference being made to the Southeast Asian fires in recent years. The available information about the effects of this pollution on the surrounding forests is reviewed, and recommendations are made for a better understanding of the impacts. The final main chapter of the book reviews recent developments in air pollution control policies in the different regions covered. This chapter is followed by conclusions (by the editors) and a subject index. The book is of interest to postgraduates and researchers in forestry, pollution studies and environmental science. The 12 main chapters of the book are all noticed separately on the CAB ABSTRACTS database.
Afficher plus [+] Moins [-]Air pollution impact on the content of carbohydrates in the needles of Norway spruce
2000
Mandre, M. | Kloseiko, J. (Estonian Agricultural Univ., Tartu (Estonia). Forest Research Inst.)
It was ascertained that the content of soluble sugars, starch and ratios between different forms of carbohydrates varied in the trees growing in areas affected by industrial production in Kohtla-Jaerve and Kunda. The ratio of soluble sugars to starch is a good indicator of the state of trees in industrial areas. This ratio depends on the level of air pollution. In the studied areas a strong relationship between the content of soluble sugars and N, Mg and K was observed in the needles of Norway spruce
Afficher plus [+] Moins [-]Content of pigments in the needles of Norway spruce and Scots pine in an area of cement production
2000
Mandre, M. | korsjukov, R. (Estonian Agricultural Univ., Tartu (Estonia). Forest Research Inst.)
The influence of air pollution from a cement plant on chlorophylls and carotenoids of the needles of Scots pine and Norway spruce was studied on the sample plots established at different distances from the emission centre in 1992, 1994 and 1999. No essential difference was observed in pigment concentrations in needles between 1992, when the emission of cement dust from the plant was very high, and 1999, when dust pollution had practically stopped. The negative influence on the synthesis of pigments in needles occurred through the alkalisation of soil and disbalances of mineral nutrients accumulation into the organism
Afficher plus [+] Moins [-]Epicuticular waxes on the needles of Norway spruce and Scots pine in the area of the Kunda cement plant
2000
Mandre, M. | Bogdanov, V. (Estonian Agricultural Univ., Tartu (Estonia). Forest Research Inst.)
The aim of the study was to compare the amount of epicuticular waxes of Norway spruce and Scots pine needles from the area of cement production in Kunda. The amount of Norway spruce waxes decreased under air pollution influences and with ageing. The quantity of waxes of Scots pine needles showed an increasing tendency in the polluted area and in one-year-old needles compared with the current-year ones. A rapid decrease in the amount of waxes was established also in the older needles of Scots pine
Afficher plus [+] Moins [-]Concentration of chemical elements in the xylem wood of Scots pines growing in different environmental conditions
2000
Paern, H. (Estonian Agricultural Univ., Tartu (Estonia). Forest Research Inst.)
Element concentrations in the xylem wood of Scots pines (Pinus sylvestris L.) growing in different soil and pollution load conditions at Narva-Joesuu and Haeaedemeeste, Estonia, were studied for temporal trends with respect to soil properties. The upper horizons of the Haeaedemeeste stand soil profile were strongly acidic compared with those of Narva-Joesuu, which were weakly acidic. Element concentrations for K, Ca, Mg, Mn and Zn in upper soil horizons were higher at the Narva-Joesuu stand and for Pb at Haeaedemeeste. Concentrations of xylem elements Mg, K, P, Pb and Cu were higher in the Narva-Joesuu sample and of Ca, Mn and Zn in the Haeaedemeeste sample. The concentrations of xylem elements except for K, Mg and Cu were poorly associated with those in soil. The increasing concentrations of Ca, K, P and in the Narva-Joesuu sample during the last decades can be explained by the larger amounts of emissions of the oil-shale fly ash by the neighbouring thermal electric power stations. Thus, the alteration of the concentrations of these elements in the xylem offer a promise for determining deposition-mediated changes in the environment
Afficher plus [+] Moins [-]Changes in forest ecosystems of Viru county influenced by industrial air pollution
2000
Mandre, M. (Estonian Agricultural Univ., Tartu (Estonia). Forest Research Inst.)
Prolonged effects of the multicomponent air pollution complexes emitted from the cement production in Kunda and oil shale processing in Kohtla-Jaerve, North-East estonia, on the forest ecosystems are discussed. It was found that atmospheric input substantially affects biogeochemical cycling in forest. The comparatively high concentrations of alkaline dusts and ash and various gaseous pollutants in the atmosphere of the investigated areas over 40 years have caused qualitative and quantitative changes in the forest soil, soil water and precipitation and in the state of forest and trees. Although the levels of air pollutants emitted by the industry have seriously decreased in recent years, alkalisation of the growth environment of trees is still essential in some regions. Alkalisation of soil and soil water in the vicinity of Kunda and Kohtla-Jaerve complicated mineral nutrition processes and disbalanced mineral elements composition in tissues, which resulted in a decrease in the increment and quality of trees
Afficher plus [+] Moins [-]Increment of conifers and its air pollution-related tendencies in Ida-Viru and Laeaene-Viru counties
2000
Ots, K. | Rauk, J. (Estonian Agricultural Univ., Tartu (Estonia). Forest Research Inst.)
The research was conducted in 1990-99 in forest observation sites in the neighbourhoods of industrial enterprises of Kohtla-Jaerve-Johvi and the cement plant of Kunda and in the control area in Lahemaa National Park. Differences between the radial increments of conifers growing under pollution and in a relatively unpolluted area were estimated. The stands selected for investigation were similar as to their edaphic conditions and forest survey indicators. The high sensitivity of conifers to long term emissions of pollutants into the atmosphere from oil shale based power engineering and chemical industry, production of building materials and fertilisers and other industrial enterprises in the investigation area is expressed as changes in the radial increment of trees with the changes depending on the pollution load and alterations in precipitation and soil
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