| Sea Cage Aquaculture
Water Quality in Conn Creek
Water samples were collected along a transect running from the north of
the farm area, through the farm and to the south of the farm. A reference
site was also included in a nearby creek unaffected by aquaculture
activities.
Sampling sites used
for water quality measurements. The station notation indicates
approximate distance (m) north or south of the Cage site.
The major factor determining the concentration of water quality
variables within Conn Creek is the season – all water quality variables
tested had significantly higher values during the wet season. Only 5 water
quality variables showed differences between locations. Of these, 3 are
dissolved species of nitrogen (NH4, NO3 and TDN) and
indicate local enrichment around the farm lease area.
Box plot of ammonium vs. location in both wet and dry
seasons. The boxes represent the 25th and 75th
percentile, the whiskers represent the 10th and 90th
percentiles. The black bar represents the median, the white bar the mean.
Outliers are indicated by symbols.
Box plot of dissolved phosphate vs. location in both
wet and dry seasons, as above.
Box plot of chlorophyll a vs. location in both wet and dry
seasons, as above.
Box plot of total dissolved nitrogen vs. location in both wet and
dry seasons, as above.
November 24, 2008 |
