Mangroves

In Lac Bay, Bonaire, a part of the mangrove forest is dying partly because of reduced water circulation through the forest. Tidal waves are the main drivers of the water circulation in the forest. In this study, the tidal behaviour is analysed based on water depth measurements from earlier studies in 2012 in Lac Bay. Time series are used to determine the tidal range (difference between minimum and maximum water depth), the dominant tidal constituent (harmonic analysis) and the water circulation through the forest (difference between the timing of highest water depth). The results show that locations close to open water in the bay have on average a large tidal range (27.8-28.1 cm) than locations in the forest (3.4-8.1 cm), with limited to no seasonal fluctuations. The dominant tide in Lac Bay is the lunisolar diurnal constituent (K1). Water depth changes from stations close to open water could be explained reasonably but in other locations they were distorted by the forest and could not be fully explained. It was found that the water moves slowly through the forest in a circular manner, moving around the islands and through the forest, thereby creating a delay in high water depths up to five-and-a-half hours.

Key words: Mangroves; Lac Bay; Water depths; Tidal range; Dominant tide; Tidal constituents

Jr Ranger presentation about the importance of mangroves and seagrasses.

Presentation from the Mangrove Restoration Workshop.  

Overview of St. Lucia's Mangroves

Used to draw comparisons with the mangroves of Aruba, Bonaire, Curacao and St. Maarten

Presented in 2021 Mangrove Restoration Workshop

How blue lcarbon supports sustainable development goals.

Presented in 2021 Mangrove Restoration Workshop

Presentation given during 2021 Mangrove Restoration Workshop

Presentation given during the 2021 Mangrove Restoration Workshop

Bonaire Mangrove Restoration Overview

Presented in 2021 Mangrove Restoration Workshop

Lac Bay is the lagoon of Bonaire; in that lagoon a mangrove forest of red and black mangroves grows. The mangrove forest of Lac provides birds and fishes of the surrounding
area with several important ecosystem services, as breeding ground, nursery and feeding area. These eco-­‐services are threatened by a reduced water circulation which causes low
water heights in the backlands and thus a reduction of the area which is available to fishes. Water in the backland was measured hypersaline, the obtained result of low water circulation and high evaporation in the backlands.

This hypersaline values may reduce the area of viable mangroves in the backlands. The lagoon and the backlands are connected  through two feeder channels and those natural channels will overgrow when no maintenance is applied causing even less water flowing into the backlands. Calculating appropriate channel dimensions and formulating a maintenance plan a certain discharge into the backlands can be ensured, which may reduce the degradation of ecosystem services.

Map of Mangrove Populations of Lac Bay

Erdmann, W., Scheffers, A. 2006. Mangrove Population of Lac (Bonaire) 1961 and 1996,  Universität Duisburg-Essen - Institut für Geographie