Assessment of regional and local biodiversity in tropical and subtropical coastal habitats in the East African Marine Ecoregion

Abstract

The transboundary networks of Marine Protected Areas (MPAs) project, TRANSMAP, assessed local turnover and regional biodiversity across the East African Marine Ecoregion, where inter-governmental co-operation has been working to connect local MPAs. The benthic fauna in the three most dominant habitats on this coastlinebeaches, mangroves and seagrasses-were studied in two Regions (Northern Region, 10-13°S; Southern Region, 25-28°S). Meiofaunal taxa were used as the model faunal group owing to their diversity and abundance across habitat types and environmental conditions. Meiofaunal abundance averaged 2,500 individuals 10 cm -2 and was generally higher in mangrove and seagrass sediments than on the beaches, and was significantly different between habitats 9 Regions. In total, 18 taxa were recorded with highest diversity in the beach samples. Diversity indices and assemblage structure were significantly different between habitats, but also Regions.

Relationships between Meiofaunal Biodiversity and Prokaryotic Heterotrophic Production in Different Tropical Habitats and Oceanic Regions

“…A comparative analysis of nematode diversity among different habitats, including reef sediments [60] , temperate seagrass beds [61] , [62] and mangrove sediments in Australia, Africa, Asia and South America [59] , [63] – [65] is difficult as different estimates (indices) of diversity have been used in different studies. Moreover, such a comparison could be biased because of the different geographic locations and sampling efforts [66] as well as by the lack of temporal replication of the surveys.…”

“…Meiofauna and nematodes, based on laboratory and in situ experiments, are in fact able to influence microbial activities and to graze their production [17] , [26] . Meiofauna and nematodes are also very sensitive to the broad variations in natural environmental conditions (tidal influence, river inputs and local rainfall, food availability, sediment chemistry, bottom current regimes, habitat heterogeneity, among the others) [17] , [27] that characterize marine sediments across all spatial scales and water depths [28] – [31] .…”

Use of satellite remote sensing for coastal conservation in the Eastern African Coast: advantages and shortcomings

“…The map of coastal habitats for 2005 constituted a reference for subsequent studies, specifically for identifying smaller areas of interest that were looked at in greater detail. It was also the base for the development of a Geographic Information System (GIS) that integrated information obtained by the various tasks of the project, namely mapping the distribution of fauna with a special interest for conservation [Barnes et al, 2011], which allowed for the mapping of biodiversity "hotspots", and a number of socio-economic factors, including the distribution of fishing boats and gears, and fishing intensity [Transmap, 2008]. This GIS was intended to have the highest possible dissemination among interested researchers and third parties, especially local and regional organizations and authorities.…”

Meiobenthic assemblages as ecological indicator of natural variability induced by ecosystem engineers

“…Seagrass beds constitute a conspicuous feature of sheltered soft-shores worldwide, and are amongst the most productive marine communities (Mateo et al, 2006;Leduc and Probert, 2011). They are key intertidal habitats and important nursery grounds (Barnes et al, 2011). Seagrasses are considered to be ecosystem engineers or structural species and are known to influence their surroundings in complex ways (i.e.…”

“…macrofauna, shrimps, small fishes and juveniles of larger fishes) are well documented in seagrass systems, but meiobenthos of seagrass free sediments is comparatively more investigated (e.g. De Troch et al, 2006;Barnes et al, 2011;Leduc and Probert, 2011;Semprucci et al, 2019;Ravaglioli et al, 2020).…”