| dc.description |
Breakdown and nutrient dynamics of submerged macrophytes were studied in Myall Lake, Australia. Mass
loss of Myriophyllum sulsagineum was the lowest (64.90%) among the studied macrophytes during the
322 days followed by charophytes (60.79%), whereas Najas marina and Vallisneria gigantea lost 91.15 and
86.02% of their respective initial mass during that time. The overall exponential breakdown rates of Najas
marina and Vallisneria gigantea were similar, with k-values of 0.24 and 0.23 day 1
, respectively. These rates
were significantly higher than the break down rates of charophytes (0.007 day 1
) and M. sulsagineum
(0.008 day 1
). During growth phase, water column depicted lower nutrient concentrations while during
decay period, significant increase in water column nutrients resulted. Release of nutrients from decomposing
macrophytes and incorporation of these nutrients into sedimentary phase as well as uptake of
nutrients by the growing macrophytes, can present a considerable cycling pathway of nutrients in Myall
lake system. The results of this study suggest that different submerged macrophytes may differ appreciably
in quality and may exhibit different decomposition rates, patterns and nutrient dynamics in aquatic ecosystems
in general, and Myall lakes in particular. |
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