Dependence of dispersion on vegetation density in a tidal creek‐mangrove swamp system
Tóm tắt
The dependence of dispersion in a tidal creek on the vegetation density in a fringing mangrove swamp is discussed through a numerical model. A secondary circulation prevails everywhere in the tidal creek‐mangrove swamp system and is generated by the overflow into the swamp at every high tide. As a result, dissolved and suspended matter moving with the circulation is trapped in the swamp for a fraction of the tidal cycle; it flows out of the swamp at ebb tide and disperses in the creek. The relation between the dispersion coefficient and the mangrove vegetation density is shown to be non‐linear. Dispersion is large both for bare and high vegetation densities and minimum for intermediate vegetation density. The ecological and management applications may be profound as our study suggests that such systems may be unstable and cannot naturally recover from excessive anthropogenic disturbances.
Tài liệu tham khảo
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