For most of the summer, the metalimnion
acts as a barrier to walleyes.
Therefore, most of the veligers observed in the current study might come from the metalimnion
and some from the epilimnion, although this needs to be confirmed in further experiments by sampling veligers at different depths.
Deeper, in the metalimnion
at 3.2-6.6 m, P[O.sup.3-.sub.4] showed a sharp increase.
All three daphniid treatments reduced resources to similar levels in the hypolimnion (9-10[degrees]C), but in the metalimnion
(19-21[degrees]C) and epilimnion (25-26[degrees]C) the rank order of relative exploitative ability was consistently D.
A third period between 10:00 am and 10:00 pm on September 13th exhibited the same sequence of heat penetrating the upper layers and generating the stepped pattern in the thick metalimnion
. From 1:00 pm on September 13th the air temperature rose from 17[degrees]C to 29.8[degrees]C (at 4:00 pm), leading to the strongest thermal stratification recorded in the period of study.
Flagellates in the fertilized lakes did not increase relative to the reference lake except for the metalimnion
of Peter Lake.
In July we observed about 450 mV in the epilimnion, after which the ORP increased up to 500 mV in the metalimnion
, and slightly decreased towards the bottom.
and E.Bic.) were concentrated in deeper layers in daytime; at night there was a large decrease, especially in the layers near the metalimnion
. Group J (Coelastrum sphaericum Nag) also contributed more during the morning, mainly between 1.0 and 3.0 m, with biomass reduction beginning at 9:00 PM (Figure 5).
The shallow enclosures were nonstratified from the surface to the sediments, whereas the deep enclosures were thermally stratified with a summer metalimnion
between 3 and 5 m [ILLUSTRATION FOR FIGURE 1 OMITTED].
The region of greatest change in temperature and/or oxygen content below the epilimnion is called the metalimnion
while the deepest, coldest, and relatively undisturbed region is the hypolimnion.
Respiration rates of zooplankton community of epilimnion and metalimnion
layers of Lake Dom Helvecio during stratified and overturn periods.