Environmental Engineering Reference
In-Depth Information
Table 1.
Pearson product-moment correlation matrix of organic matter pools, sources and
sinks within the Cariaco Basin; oxic layer (
<
250 m), redoxcline (250-450 m) and anoxic waters
(
>
450 m). NPP = net primary production, POC = particulate organic carbon, PON = particulate
organic nitrogen, DOC = dissolved organic carbon and Microbial Variables = abundances of
prokaryotes, flagellates and viruses as well as BNP and dark DIC assimilation (all calculated
separately). Numbers in parentheses = minimum number of variates compared (n).
NPP
POC
PON
DOC
Microbial variables
Chlorophyll a
1
<
250 m
0.62***
0.61***
0.59***
ns
ns
250-450 m
na
ns
ns
ns
ns
>
450 m
na
ns
ns
ns
ns
(6-79)
2
(91)
(74)
(77)
(46)
NPP
1
<
250 m
0.39***
0.42***
ns
ns
250-450 m
ns
ns
ns
ns
>
450 m
ns
ns
0.47**
ns
(73)
(76)
(45)
(8-78)
POC
<
250 m
0.82***
ns
ns
250-450 m
0.62***
ns
ns
>
450 m
0.72***
ns
ns
(71)
(40)
(6-73)
PON
<
250 m
ns
ns
250-450 m
ns
ns
>
450 m
ns
ns
(43)
(7-71)
DOC
<
250 m
ns
250-450 m
ns
>
450 m
ns
(6-42)
1 - measured in upper 100 m only
2 - range in sample size (n) for abundances of prokaryotes, flagellates and viruses as well as BNP and dark
DIC assimilation
na = not applicable
ns = not significant (p
>
0.05); *=p
<
0.05; **=p
<
0.01; *** = p
<
0.001)
bial communities in this layer are explored below and include; accumulation
of particle-bound cells on water density surfaces within a pycnocline, parti-
cle translocation by migrating animals, lateral transport of organic-rich waters
at depth, lower prokaryotic mortality rates and in situ production of organic
matter.
The Cariaco Basin's pycnocline typically is found between 30 and 200 m,
where σ
θ
increases from
24.890 to 26.390 kg m
−
3
. Water densities below
∼
