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Rapid climatic warming in the past: reconstruction and modelling
2000
Vandenberghe, J. | Isarin, R.F.B. | Renssen, H.
Sustainability and the cultural factor: results from the Dutch Goes Mass Public Module
2000
Ester, P. | Vinken, H.
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.
Mostrar más [+] Menos [-]Air pollution and the forests of developing and rapidly industrializing regions
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.
Mostrar más [+] Menos [-]Forests in Virumaa
2000
Ratas, R. (Estonian Agricultural Univ., Tartu (Estonia). Inst. of Environment Protection) | Ratas, J. (Tallinn Technical University, Tallinn (Estonia))
Virumaa has the richest forest resources in Estonia. The area covered with forests in Virumaa amounts to 51.3 per cent (total in Estonia 49 per cent). Pine, birch and spruce forests dominate. A large part of forests are under technogenous pressure (oil-shale mining, power engineering etc.). The total amount of all the fellings in 1999 was 1.061 million cubic metres (in Estonia totally 6.704 mln. cubic metres). The volume of fellings has reached the critical level close to the annual increment of forests. Therefore, the volume of cutting down forests should not be increased
Mostrar más [+] Menos [-]On the geochemistry of soil humus horizon in North-East Estonia
2000
Petersell, V. | Mottus, V. (Geological Survey of Estonia, Tallinn (Estonia))
The paper is based on the data of geochemical mapping of the humus horizon of soil and geochemical monitoring of soil carried out in 1986-94. These data have been supplemented with results of later investigations. The authors describe the formation of parent rock of soil in NE Estonia and its major geochemical features. The main plant nutrient elements and those having a negative influence of plant growth and the development of animate nature in the case of their elevated concentration in soil are observed. Components are areal distribution of technogenous atmospheric pollution falling on the ground surface in NE Estonia are also dealt with. The chemical composition of the humus horizon of soil in NE Estonia is variable, the variation coefficient of several elements exceeding 100 per cent. The trends of lateral changes in the concentration of elements are accidental. Such heterogeneity is mainly due to great variability of parent rocks of soil. Glacial deposits formed from Proterozoic crystalline rocks of Fennoscandian origin, as well as the Vendian and Paleozoic sedimentary rocks, among the latter mineralised or ore-bearing varieties, Dictyonema shale and phosphorite. Mean concentrations of elements in the humus horizon of NE Estonian soils are close to the respective concentrations of the whole Estonian territory, but differ considerably from the mean concentrations of all continents
Mostrar más [+] Menos [-]Defoliation of conifers in the North Estonian industrial region
2000
Ots, K. | Rauk, J. (Estonian Agricultural Univ., Tartu (Estonia). Forest Research Inst.)
In 1985-99 studies were carried out in the area of the Kunda cement plant on North Estonian coastal plain on sample plots stretching 1.5 and 2.5 km east and 2 km and 3 km west, where changes in crown damages and radial increment of pine and spruce were estimated. The selected stands were with 0.7-0.8 density and II quality class, with moderately dense or sprase understorey, 75-85-year-old Myrtillus site type pine or spruce stands. Practically every tree in the area of intensive dust pollution had signs of damage. The relations between the defoliation and radial increment in the region were not linear. Weak defoliation (up to 25 per cent) influences slightly the radial growth. The correlations were more evident on Pinus sylvestris with more than half of the trees in the area having moderate or strong defoliation (at least 30-35 per cent). We suppose that defoliation, which leads to a decrease in the assimilating area of trees, causes essential changes in physiological processes. In the region of intensive pollution stress the radial increment decreased along with the defoliation level on both Pinus sylvestris and Picea abies
Mostrar más [+] Menos [-]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
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