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Effect of copper smelting air pollution on the mites (Acari) associated with young Scots pine forests polluted by a copper smelting works at Giogów,Poland. I. Arboreal mites
1997
Seniczak, Stanisław | Dąbrowski, Janusz | DŁUGOSZ, JACEK
The arboreal mites and epiphytes in young Scots pine forests (plant association Leucobryo-Pinetum) polluted by a copper smelting works at Głogów, were investigated. The concentration of heavy metals in Scots pine bark and epiphytes increased towards the pollution source. Copper was accumulated mainly by algae, but lead was accumulated mainly by lichens; these epiphytes accumulated more heavy metals than tree bark. A high concentration of heavy metals was harmful to mites, especially to Oribatida, and to lichens, but algae tolerated these pollutants. The number of oribatid species decreased towards the pollution source, along with the increasing concentrations of heavy metals in tree bark and epiphytes. Among mites, the following categories were distinguished: a) sensitive to heavy metals, b) sensitive to a high concentration but tolerant of small concentrations and c) tolerant of these metals. The mites inhabited mainly the lower section of trees.
Mostrar más [+] Menos [-]Diagnosis of boron, fluorine, lead, nickel and zinc toxicity in citrus plantations in villarreal, spain
1997
Aucejo, Antonio | Ferrer, José | Gabaldón, Carmen | Marzal, Paula | Seco, Aurora
In the late 1980s, citrus plantations in the area of Villarreal (Spain) showed injuries similar to those previously reported for boron and fluorine toxicity. The area was affected by the disposal of industrial wastewater, mainly from ceramic industries. Conjunctive uses of surface water, groundwater and wastewater for irrigation had taken place. A survey was conducted at 25 orchards to assess leaves and soil for their boron, fluorine, lead, nickel and zinc contents. Wastewater and groundwater were also analyzed to corroborate the presence of these pollutants. The results showed that both boron and fluorine contents were greater than those reported as excess at the most part of the orchards included in the study. Heavy metals toxicity effects were not confirmed. Boron pollution was attributed to industrial wastewater spills and fluorine contamination from atmospheric pollution.
Mostrar más [+] Menos [-]THE trapping of fly-ash particles in the surface layers of sphagnum-dominated peat
1997
Punning, Jaan-Mati | ALLIKSAAR, TIIU
The movement of fly-ash particles in a sequence of Sphagnum moss was studied in laboratory experiments and field investigations. The data obtained in the laboratory show that only 0.8% of particles, placed on the surface of a 6–10 cm thick Sphagnum layer, were washed out with water (700–750 mm) during the 241 days of the experiment. The majority of added particles were fixed in the upper part (90% in 1–3 cm) of the moss layer. A SEM study indicates that sorption is slightly species-dependent due to the micromorphological parameters of the Sphagnum species. The storage of particles by Sphagnum mosses allows the use of natural sequences to study the history of atmospheric pollution. The distribution of particles in the upper part of moss layers in Viru Bog (50 km east of Tallinn, North Estonia) shows good agreement with the known air pollution history in Tallinn.
Mostrar más [+] Menos [-]A screening procedure to evaluate air pollution effects in Region 1 wilderness areas, 1991
1997
Stanford, Jack | Acheson, Ann | Brakke, David | Eversman, Sharon | Savig, Kristi | Eilers, Joe