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The interaction of So2 and root-knot nematode on tomato.
1993
Khan M.R. | Khan M.W.
Relationship between foliar injury and changes in antioxidant levels in red and Norway spruce exposed to acidic mists.
1991
Chen Y.M. | Lucas P.W. | Wellburn A.R.
Vapour of the free acid of the herbicide 2,4-D is toxic to tomato and lettuce plants.
1991
Breeze V.G. | Rensburg E. van
Persistent effects of ozone on needle water loss and wettability in Norway spruce.
1990
Barnes J.D. | Eamus D. | Davison A.W. | Ro Poulsen H. | Mortensen L.
Niveaux d' ozone et endommagement foliaire sur quelques essences mediterraneennes.
2001
Dalstein L. | Teton S. | Cottereau C. | Vas N.
En France, dans les Alpes-Maritimes, une recherche est menee pour connaitre l' impact eventuel de l' ozone sur l' endommagement foliaire repere ces dernieres annees sur peuplements de pins d' Alep, sylvestre et cembro. L' etude s' effectue dans le cadre d' un contrat franco-italien Interreg 2 et d' un programme Primequal. Cet article donne tout d' abord, les resultats pour l' ete 1999, interessant les niveaux de concentration d' ozone mesures depuis le littoral azureen jusqu' au massif du Mercantour au moyen d' analyseurs physico-chimiques et de capteurs passifs. La dose d' AOT 40 et la somme cumulee des concentrations horaires sont indiquees pour les periodes de mesure estivales. Les capteurs passifs se situent notamment parmi des placettes de suivi d' arbres. Afin d' apprehender l' impact de la pollution par l' ozone sur ces ecosystemes forestiers, des notations d' endommagement foliaire sont effectuees. Des correspondances sont recherchees entre les niveaux moyens d' ozone et les degres d' atteinte des trois principales essences suivies (pins d' Alep, sylvestre et cembro). Il semble y avoir une correlation entre augmentation des concentrations d' ozone et endommagement foliaire au moins en ce qui concerne les pins cembro.
Afficher plus [+] Moins [-]Ectomycorrhizal associations in Norway spruce stands influenced by long lasting air pollution (Silesian Beskid Mountains, Poland)
2002
Rokicka-Kieliszewska, B. (Polish Academy of Sciences, Kornik (Poland). Institue of Dendrology) | Rudawska, M. | Staszewski, T. | Kurcynska, E. | Karlinski, L.
Norway spurce (Picea abies L.) is the dominating tree species in the Silesian Beskid Mountains. The mountain forests are under severe climatic conditions, such as low temperatures, short growing season, strong winds, high annual precipitation, a long-time snow cover. The forests have been exposed also for about half century to gaseous and dust pollutants emitted by large industrial centres in the Czech Republic, Germany and Poland. Anthropogenic impacts may influence negatively the growth of tree fine roots, can develop ectomycorrhizas and alter the communities of ectomycorrhizal fungi and other microorganisms in soil. Ectomycorrhizal communities at the both forest sites were dominated by the same two morphotypes, which were further studied using the PCP-RFLP analysis for identification of the fungal species
Afficher plus [+] Moins [-]Long-term effect of alkaline air pollutants on forest ecosytems
2002
Caboun, V. | Mindas, J. | Priwitzer, T. | Pavlenda, P. | Istona, J. | Pavlendova, H. (Forest Research Institute, Zvolen (Slovak Republic))
The effect of alkaline air pollutants appears on 98% of the area of forests in Slovakia. Despite a local impact of magnesite air pollutant type is very significant as to the degree and extent of damage. Despite enormous efforts of magnesite plants only a low reduction of dust fallout was reached. While in the years 1978-1979 emission of Mg dust reached 7396.5 tons and emission of SO2 1133.5 tons, in the years 1990-1991 respective figures were 1174.5 tons of Mg dust and 1114 tons of SO2. It means that the amount of emitted SO2 has not changed but the amount of emitted dust has dropped 6.5 times. On the basis of research results the whole attacked territory was divided into four zones of endangerment and there were tested various reclamation and revitalization measures successfully
Afficher plus [+] Moins [-]Effects of preparatory stands on forest site restoration
2002
Remes, J. | Podrazsky, V. (Czech University of Agriculture, Prague (Czech Republic). Faculty of Forestry)
The main aims of the preparatory stands in air pollution areas are growth development, successfull dynamics of the plants and fast creation of the stand microclimate with favourable effect on soil conditions. This process is documented by height and diameter increment. The results confirm different growth dynamics of the particular species. Larch is the species with the best growth dynamics of selected species on experimental plots. On the other hand, beech is the worst species for reforestation in this condition. One of the causes could be damage by frost
Afficher plus [+] Moins [-]Heavy metals and pedogenic processes in the Krkonose National Park (Czech Republic)
2002
Bonifacio, E. | Santoni, S. | Zanini, E. (Universita di Torino, Grugliasco (Italy). DIVAPRA Chimica Agraria)
Remarkable differences were found in soil development on three sites. At Modru Dul (the least damaged site) Sopdosols and Inceptisols were found, in Alzbetinska (moderately damaged) Entisols are common, while in Mumlavksa hora (highly damaged) the representative soils are several kind of Podzols, with variable degree of drainage restriction and organic soils. The heavy metal content is always rather low and the vertical distribution does not indicate any appreciable contribution of atmospheric contamination
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