Environmental Engineering Reference
In-Depth Information
Fig. 6.2 A long-handled sampling pole with a collection bottle on the end can be used to avoid
disturbing sediments and/or facilitate collecting water samples from deeper areas of the wetland
to contact sediments since this can significantly influence readings for parameters
such as dissolved oxygen. This can sometimes be challenging in shallower systems
or if it is necessary to wade into the wetland to access open water. If the wetland is
large and deep enough, accessing open water by boat can help avoid these issues
although attention must still be paid to where the water quality probe is located in
the water column. The use of a long-handled sampling pole with a collection bottle
on the end (Fig.
6.2
) can be used to pull grab samples of water that can be analysed
on shore with a water quality meter or transferred to appropriate containers for
determination of wet chemistry parameters. In wetlands with deeper basins, depth-
specific samples for wet chemistry analyses can also be collected using a commer-
cial sampling device such as a Van Dorn sampler (Wetzel and Likens
2000
). Basic
quality assurance for wet chemistry procedures includes following appropriate
sample storage and preservation techniques and conducting the analyses within
the prescribed time frame to ensure sample viability (Table
6.2
). The use of
properly cleaned glassware to avoid inaccurate readings due to contamination is
also a key issue if conducting sample analyses in house. Appropriate sample
labelling and tracking methods are also important considerations. Guidance on
analytical quality assurance and data handling is provided by Briggs (
1996
) and
APHA, AWWA and WEF (
2005
)
