Prövning av bekämpningsmedel mot skadedjur 1975

vokKirjasto Aj-

Tuhoeläinten tarjunta-aineiden koetulokset 1975

vokKirjasto Aj-

Water striders (Heteroptera, Gerridae) as bioindicators of heavy metal pollution

Heavy metal contents of water striders collected near a steel factory and from control sites were analyzed by AAS. The average concentrations µg/g of dry weight found near the factory vs. the control areas were: Al 76, 65; Fe 840, 330; Mn 49, 37; Zn 310, 280; Cu 44, 42; Cd 1.6, 6.5, respectively. In most cases Ni and Pb concentrations were below the determination limit in both sites. There were significant differences between sites in the concentrations of iron and cadmium. Fifth instar larvae had higher iron content than adults, but sexes did not differ in heavy metal content. There were also significant differences between different water strider species as accumulators of zinc, aluminium and cadmium. It is concluded that water striders seem suitable as bioindicators of heavy metals

Cadmium in insects after ash fertilization

Ash fertilization of forests returns nutrients to forest ecosystems and has a positive effect on soil pH, but it also may elevate Cd concentrations of forest biota. Cadmium concentrations of some forest insects (Formica ants, carabids and Coleopteran larvae from decaying wood) were investigated in southern Finland, where two plots were fertilized with wood ash, while two other plots represented unfertilized control plots. In ants, mean Cd concentration was 3.6 ± 1.4 mg/kg, with nest workers having significantly higher concentrations than workers trapped in pitfall traps. Concentrations at fertilized and unfertilized plots were similar. In carabid beetles, the average Cd concentration of Carabus glabratus was 0.44 ± 0.36 mg/kg, with no significant difference between control plots and fertilized plots. In another carabid beetle, Pterostichus niger, mean Cd concentration was higher at fertilized plots compared to control plots. We conclude that the variation of Cd concentrations in the insects studied is more efficiently controlled by species-specific differences than fertilization history of the forest floor

Prövning av bekämpningsmedel mot skadedjur 1976

Nimekkeen selvennys: Avdelningenför skadedjursforskning.Prövning av bekämpning smedelmot skaddejur 1976 Resultat.vokKirjasto Aj-

Tuhoeläinten torjunta-aineiden koetulokset 1976

Nimekkeen selvennys: 532-2 Torjunta-ainelain edellyttämät tehtävät Tutkimustuloksia vuodelta 1976.vokKirjasto Aj-