Earthworms play key roles in soils and sublethal effects of environmental toxicants on these organisms should be taken seriously, since they might have
detrimental effects on higher ecological levels. In laboratory experiments we have assessed sub-lethal effects (body
mass change and cast production) of imidacloprid on two
earthworm species commonly found in different agricultural soils (Lumbricus terrestris and Aporrectodea caliginosa). After 7 days of exposure in contaminated soil, a
significant loss of body mass was found in both species
exposed to imidacloprid concentrations as low as
0.66 mg kg-1
dry soil. These losses ranged from 18.3 to
39% for A. caliginosa and from 7.4 to 32.4% for L. terrestris, respectively. Changes in cast production, a new
biomarker previously validated using L. terrestris, was
assessed by soil sieving using the recommended mesh size
(5.6 mm) for L. terrestris and three different mesh sizes for
A. caliginosa (5.6, 4 and 3.15 mm). The 4 mm mesh size
proved to be the most suitable sieve size for A. caliginosa.
Cast production increased by 26.2% in A. caliginosa and
by 28.1% in L. terrestris at the lowest imidacloprid concentration tested (0.2 mg kg-1
dry soil), but significantly
decreased at higher concentrations (equal to and above
Earthworms play key roles in soils and sublethal effects of environmental toxicants on these organisms should be taken seriously, since they might have
detrimental effects on higher ecological levels. In laboratory experiments we have assessed sub-lethal effects (body
mass change and cast production) of imidacloprid on two
earthworm species commonly found in different agricultural soils (Lumbricus terrestris and Aporrectodea caliginosa). After 7 days of exposure in contaminated soil, a
significant loss of body mass was found in both species
exposed to imidacloprid concentrations as low as
0.66 mg kg-1
dry soil. These losses ranged from 18.3 to
39% for A. caliginosa and from 7.4 to 32.4% for L. terrestris, respectively. Changes in cast production, a new
biomarker previously validated using L. terrestris, was
assessed by soil sieving using the recommended mesh size
(5.6 mm) for L. terrestris and three different mesh sizes for
A. caliginosa (5.6, 4 and 3.15 mm). The 4 mm mesh size
proved to be the most suitable sieve size for A. caliginosa.
Cast production increased by 26.2% in A. caliginosa and
by 28.1% in L. terrestris at the lowest imidacloprid concentration tested (0.2 mg kg-1
dry soil), but significantly
decreased at higher concentrations (equal to and above
การแปล กรุณารอสักครู่..
![](//thimg.ilovetranslation.com/pic/loading_3.gif?v=b9814dd30c1d7c59_8619)