Production and consumption of tropical seagrass fields in eastern Indonesia measured with bell jars and microelectrodes
Lindeboom, H.J.; Sandee, A.J.J. (1989). Production and consumption of tropical seagrass fields in eastern Indonesia measured with bell jars and microelectrodes. Neth. J. Sea Res. 23(2): 181-191
In: Netherlands Journal of Sea Research. Netherlands Institute for Sea Research (NIOZ): Groningen; Den Burg. ISSN 0077-7579; e-ISSN 1873-1406, meer
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| Auteurs | | Top |
- Lindeboom, H.J., meer
- Sandee, A.J.J.
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| Abstract |
During the Indonesian-Dutch Snellius-II Expedition the production and consumption of tropical seagrass species were measured with bell jars at four sampling stations in eastern Indonesia. Applying a conversion factor of 0.29, the amount of carbon fixed and mineralized was calculated from the recorded oxygen evolution. The gross production of the different seagrass communities was found to be between 1230 and 4700 mg C·m-2·d-1. The consumption lay between 860 and 3860 mg C·m -2·d-1. From these data a relatively low net production of 60 to 1060 mg C·m-2·d-1 could be calculated. At one sampling station incubations were carried out at different depths in a sloping Halodule uninervis (Forssk.) Aschers meadow, which indicated that seagrasses above a depth of about 2 m may become subject to photoinhibition. A linear correlation between biomass and measured production was found for Thalassia hemprichii (Ehrenb.) Aschers. Above a biomass of 100 g DW·m-2 the production per unit of biomass decreased due to self shading. Using microelectrodes the oxygen production of epiphytes was found to be 230 mg C·m-2 leaf surface·d-1. at 1900 µE· m-2·s-1 assuming an epiphyte coverage of 40%. This indicated that up to 36% of the primary production in a seagrass community may be attributed to epiphytes. The seagrass fields in Indonesia were found to be healthy ecosystems with a high primary production, but organisms within the communities use the abundance of organic matter very efficiently, creating net production rates of 100 to 300 mg C·m-2·d-2 which are similar to barren areas. |
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