impoundment, suspended material in the water should not produce any
long term negative effects on surrounding waters. According to the
water samples taken and literature listing local wildlife (Snelson, et
al, 1979), the salinity change will have little effect on the majority
of the resident species. Heinle, D. R., et al, (1976) found that
detritus is more rapidly incorporated into higher trophic levels by
marine amphipods. Theoretically, any setbacks from mortality rates
among freshwater organisms will be equalized within a very short period
of time with an increase in energy flow. Due to the pre-predator limita-
tion factor, the upper levels of the food web, the carnivores, will not
be adversely affected since they have not been dependent upon these or-
ganisms in the past. As the food web expands, the top carnivores will
be drawn into the lagoon by the availability of food.
Submerged vegetation is absent in all of the impoundments; mangrove
leaves and stems mat the bottoms of the three easternmost impoundments.
These three impoundments have their own specialized ecosystem, but con-
sidering the "edge-effect" described by Gucinski (1978) a vast
resource
of energy is being withheld from the estuary. The four impoundments
equal about one-tenth the area of the lagoon they will empty into (see
Figure 3). Yet, they have twice the acreage of shoreline mangroves.
This translates into a two-fold increase of energy resulting from man-
grove leaf detritus alone. Citing a value for mangrove leaf detritus
production from Odum and Heald (1972) of eight tons dry weight per
hectare per year and another from E. P. Edum (1971) of 10,000 to 25,000
kilocalories per square meter of gross production, one can visualize the
extent of the benefits which can be derived from opening energy pathways
to estuaries and other potentially productive waters. According to


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