Linsley Pond in North Branford Connecticut has provided an ecosystem for
study for many limnologists. It has fallen victim to cultural (human induced,
so accelerated as to be disruptive of community structure) eutrophication.
A series of blooms dominate its waters. In some years blooms are obvious
for 12 months. Figure 1 presents the series of blooms that occurred during
the 2 year study period. Figure 2 offers an explanatory diagram. In all cases
tested (all bloom dominant forms were tested), the heat-labile metabolic
products of each organism would inhibit (or be neutral to) its predecessors,
and would stimulate (or be neutral to) its successors. That is A would favor
B, B would favor C, B would inhibit A, C would inhibit B. If you are curious
as to additional details, the two papers from SCIENCE 1977, 1978
(bibliography for allelochemical page) can provide them. More instances of
effect than of neutrality occurred.
Figure 3 provides evidence for the ubiquitous distribution of allelochemical
activity among the plankton in a eutrophied system. Surely, the confined waters of
a eutrophied lake are rich with biologically active molecules. At times, considering
the bloom pattern of Linsley, these active materials have significant effects
on the selection of the dominant plankon, on the sequence of blooms.
