Publication Date:
2021-06-29
Description:
The effect of productivity on species variety has been studied by countsof diatom species on glass slides at favorable and unfavorable stations withinSilver Springs. Species variety has been presented in a measure that is independentof sample size, "species per cycle". This measure is based on the linear increase of accumulated species with logarithmic increase of individuals counted, which has been found approximately true for many kinds of populations in many communities. Diatom productivity was measured by the rate of chlorophyll accumulation. The poor station accumulated diatoms and chlorophyll slowly and was characterized by a large species variety. There was little change after 79 days. The rich station accumulated diatoms and chlorophyll rapidly and was characterized by a small species variety that decreased for 93 days as the density of the population increased. These results indicated that species variet was decreased by conditions of high productivity possibly through the action of high densities and competition.Twelve new diurnal production curves were obtained including two more on Silver Springs and one each for 10 different Florida Springs. A shallow oligohaline spring possessed the highest productivity of 58.0 gm/m2/day; a shaded and anerobic spring possessed the lowest producvitiy of 0.66 gm /m2/day. Findings in further studies in Silver Springs indicated a two fold diurnal chlorophyll fluctuation in the pseudoplankton going downstream, photosynthetic quotients corresponding to carbohydrate production on winter or heavily clouded days, and higher quotients corresponding to protein production on sunny, summer days; evidences that bell jar estimates of respiration in flowing water communities lead to underestimates; recalculation of mean depth of plant beds leads to a 5% estimate of photosynthetic efficiency for Silver Springs (rather than 8%). Correlated with a 20% decrease in the discharge associated with widespread drought in 1954-55 the oxygen of the main boil dropped from 2.5 ppm to 1.7 ppm. A production measurement by the diurnal oxygen and carbon-dioxide curve method was made in a somewhat isolated "boat basin." Efficiency of production in this stationary, plankton containing water of Silver Springs origin was about 1%. Further evidence was obtained of nitrate increase in water flowing from anaerobic springs over blue-green algae. The area based chlorophyll of the benthic Silver Springs community was similar to that in forests and lakes of Europe. (63 pages)
Keywords:
Ecology
;
Limnology
;
diatoms
;
Silver Springs
;
Florida
;
productivity
Repository Name:
AquaDocs
Type:
monograph
Format:
application/pdf
Format:
application/pdf
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