| Autor: |
Sullivan, Michael J., Moncreiff, Cynthia A. |
| Předmět: |
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| Zdroj: |
Journal of Phycology; Mar1988, Vol. 24 Issue 1, p49-58, 10p |
| Abstrakt: |
Primary production roles of edaphsc algae associated with the sediments beneath four monospecific canopies of vascular plants were determined over an annual cycle in a Mississppi salt marsh. The edaphic algal flora was dominated by small, motile pennate diatoms. Algal production (as measured by [SUP14]C uptake) was generally highest in spring-early summer and lowest in fall. Hourly rates ranged from a lou of 1.4 mg C/m[SUP2] in Juncus roemerianus Scheele to a high of 163 mg C/m[SUP2] beneath the Scirpus olneyi Gray canopy. Stepwise multiple regressions identified a soil moisture index and chlorophyll a as the beat environmental predictors of hourly production; light energy reaching the marsh surface and sediment and ate temperature proved of little value. Adding the relative abundances of 13 diatom taxa to the set of independent variables only slightly increased R[SUP2]; however, virtually all variables selected were diatom taxa. R[SUP2] was only 0. 38 for the Spartina alterniflora Loisel. habitat but ranged from 0. 70 to 0.87 for the, remaining three vascular plant zones. Annual rates of algal production (g C/m[SUP2] were estimated as follows: Juncus (28). Spartina (57). Distichlis spicata L. Greene (88). and Scirpus(151). The ratio of annual edaphic algal production to vascular plant net aerial production (EAP/VPP) was 10-12% for the first three habitata and 61% for Scirpus. Chlorophyll a concentrations, annual algal production rates, and EAP / VPP values were comparable to those determined in Texas. Delaware, and Massachusetts salt marshes but lower than those reported for Georgia and particularly California marshes. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
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