LaMotte BRASS BOTTOM SAMPLING DREDGE 1061 - Manual

BRASS BOT TOM SAM PLING DREDGE
CODE 1061
IN TRO DUC TION
The LaMotte Bottom Sampling Dredge, a modification of the well-known
Peterson dredge, provides a convenient method for collecting bottom
sediments. It is used for collecting bottom sediments which may contain
mud, sand, ooze, and gravel; however, it is not designed to collect samples
from rock bottoms. By using a bottom sampling dredge, a number of
different analyses can be made. Since the bottom sediments represent a
good area to find macroinvertebrates and benthic algae, the communities
of organisms living on or in the bottom can be easily studied
quantitatively and qualitatively. A chemical analysis of the bottom
sediments can be conducted to determine what chemicals are available to
the organisms living in the bottom habitat. Also, the structural
characteristics of the bottom may be examined and related to the
biological and chemical analysis. All of these different studies are made
possible through the use of a bottom sampling dredge.
Whenever samples of the bottom are taken, every effort must be made to
insure that the samples are truly representative of the whole area. Much of
this depends upon the judgment of the individual taking the sample and
their individual study objectives. In most cases, as many samples as
possible should be taken since one sample has no value statistically. The
time interval between sampling and analysis is not critical for a
mechanical or physical analysis, but immediate analysis is recommended
for both biological and chemical examinations.
L Mott