Order this information in Print

Order this information on CD-ROM

Download in PDF Format

     

Click here to make tpub.com your Home Page

Page Title: G.3.1.2 Taxonomy.
Back | Up | Next

Click here for a printable version

Google


Web
www.tpub.com

Home


   
Information Categories
.... Administration
Advancement
Aerographer
Automotive
Aviation
Combat
Construction
Diving
Draftsman
Engineering
Electronics
Food and Cooking
Math
Medical
Music
Nuclear Fundamentals
Photography
Religion
USMC
   
Products
  Educational CD-ROM's
Printed Manuals
Downloadable Books
   

 

next generation of cocoons. E. fetida has a maximum life expectancy of 4 to 5
years, although between 1 and 2 years is more usual.
Eisenia fetida is an epigeic species (i.e., they live and feed on the surface)
that rarely inhabits agricultural soils but is found in compost piles, manure piles,
and other disturbed sites rich in organic matter. The rate of soil consumption in
the laboratory by E. fetida individuals weighing 300 mg has been estimated at 16
mg soil/individual/day (Stafford and Edwards 1985).
Worms digest the microorganisms from ingested soil and organic debris,
which illustrates their interactions with the soil environment. Independently of
whether mineral matter or fibrous organic material was ingested, approximately
2.5 h were required at 25 EC for E. fetida to pass ingesta from mouth to anus
(Hartenstein, Neahauser, and Narahara 1981).
G.3.1.2 Taxonomy.
The taxonomic status of what Bouch (1992) calls the complex is unclear in
the literature. Some authors consider this complex to consist of two subspecies,
E. fetida fetida and E. fetida andrei, while other authors consider the complex to
consist of two separate species, E. fetida and Eisenia andrei. This guide chooses
to use the subspecies designations. The dorsal surface of E. f. andrei is uniformly
reddish, while E. f. fetida is striped or banded. Bouch (1992) states that the
andrei form is relatively homogeneous, while fetida may be multispecific. It is
recommended that the andrei form be used as the test organism, that is,
E. f. andrei.
G.3.2 Laboratory procedures
Culture of Test Organisms. Earthworms are obtained through either
culture procedures or from commercial vendors.
Age. Tests with E. fetida tests should use sexually mature fully clitellate
earthworms.
Experimental Design. Decisions concerning the various aspects of
experimental design, such as the number of replicates, the number of test
containers, and the mass of earthworms, should be based on the amount of tissue
material needed for chemical analysis.
Test Material. Test materials are (1) the dredged material being evaluated,
(2) reference soil, and (3) control material such as earthworm culture media for
use in evaluating test acceptability.
Test Containers. Test material is placed in transparent Plexiglas cylinders
30 cm deep and 15 cm in diameter. The cylinder ends are closed with a 17-cm
PVC and either 340 Nytex mesh or cotton muslin cloth. The bottom end is then
placed in a 20-cm-diam plastic dish of test water to allow water movement into
the substrate and allow earthworms to move into areas of optimum moisture.
G4
Appendix G Animal Bioaccumulation Test Procedures

Privacy Statement - Press Release - Copyright Information. - Contact Us - Support Integrated Publishing

Integrated Publishing, Inc. - A (SDVOSB) Service Disabled Veteran Owned Small Business