Study

Colonization of non-planted mangrove species into restored mangrove stands in Gazi Bay, Kenya

  • Published source details Bosire J.O., Dahdouh-Guebas F., Kairo J.G. & Koedam N. (2003) Colonization of non-planted mangrove species into restored mangrove stands in Gazi Bay, Kenya. Aquatic Botany, 76, 267-279.

Actions

This study is summarised as evidence for the following.

Action Category

Directly plant trees/shrubs: brackish/saline wetlands

Action Link
Marsh and Swamp Conservation
  1. Directly plant trees/shrubs: brackish/saline wetlands

    A replicated, paired, before-and-after, site comparison study in 1994–1999 involving three areas of planted mangroves in southeast Kenya (Bosire et al. 2003) reported that the planted areas had a similar density of trees to mature natural forests after five years, but contained fewer adult tree species and differed in other structural metrics. Unless specified, statistical significance was not assessed. The three planted areas were initially bare sediment. After five years, they contained 3,330–7,640 trees/ha (vs natural: 3,770–4,300 trees/ha; see original paper for on individual species density). Each planted area contained only one species of adult tree (i.e. the planted species), whereas natural areas contained 1–4 species of adult tree (but were always dominated by a single species, comprising 69–100% of individuals). Planted areas contained 4–5 species of seedling (vs natural: only 3 species). Vegetation in planted areas was less structurally complex than in natural areas (reported as a complexity index), was only 3–5 m tall on average (vs natural: 6–8 m) and had a basal area of only 3–12 m2/ha (vs natural: 27–42 m2/ha). In two of three comparisons, planted areas contained significantly fewer seedlings than natural areas (but more in the other comparison). After five years, denuded areas that were not planted remained unvegetated. Methods: In 1994, mangrove saplings were planted into three areas (0.3–6.7 ha) of bare, tidal sediment (historically logged mangrove forest). Each area was planted with one species: grey mangrove Avicennia marina, mangrove apple Sonneratia alba or loop-root mangrove Rhizophora mucronata. In 1999, vegetation was surveyed in the planted areas (three 100-m2 plots/area). For each planted area, an area of natural forest and denuded but unplanted sediment were also surveyed.

    (Summarised by: Nigel Taylor)

Output references
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