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Exploring the relationships between biodiversity and benthic habitat in the Primeiras and Segundas Protected Area, Mozambique

Teixeira, Luisa LU (2015) In Student thesis series INES NGEM01 20142
Dept of Physical Geography and Ecosystem Science
Abstract (Portuguese)
A Reserva dos Arquipélagos Primeiras e Segundas, localizada no norte de Moçambique, é a maior zona marítima protegida de África, estendendo-se por mais de 200 km de costa. Apesar da sua importância para a economia local, informações sobre os seus ecossistemas marinhos, e particularmente habitats bênticos, são escassas. Doze atóis foram mapeados na região usando object-based image classification de imagens de satélite de muito alta resolução (IKONOS, Quickbird, and WorldView-2). Dados georreferenciados sobre a superficie bêntica e profundidade foram recolhidos em três campanhas de campo, abrangendo um total de quarto atóis e dois baixos. Os mapas produzidos permitem a estimativa de três tipos distintos de superfície coralina (campo,... (More)
A Reserva dos Arquipélagos Primeiras e Segundas, localizada no norte de Moçambique, é a maior zona marítima protegida de África, estendendo-se por mais de 200 km de costa. Apesar da sua importância para a economia local, informações sobre os seus ecossistemas marinhos, e particularmente habitats bênticos, são escassas. Doze atóis foram mapeados na região usando object-based image classification de imagens de satélite de muito alta resolução (IKONOS, Quickbird, and WorldView-2). Dados georreferenciados sobre a superficie bêntica e profundidade foram recolhidos em três campanhas de campo, abrangendo um total de quarto atóis e dois baixos. Os mapas produzidos permitem a estimativa de três tipos distintos de superfície coralina (campo, retalhos e falésias), a diferenciação de areia, cascalho e rocha e a detecção de ervas marinhas e macroalgas castanhas, identificando-se até 24 habitats bênticos, com precisão média superior a 50%. Novas informações recolhidas indicam a presença de superfícies bênticas profundas a prolongarem-se dos atóis, o que sugere a necessidade de pesquisa adicional, e está de acordo com o conhecimento actual da existência de um recife de coral quase contínuo desde o Quénia até Moçambique. A análise da biodiversidade das comunidades coralinas e ictiológicas apoia a percepção local de que os ecossistemas estão em declínio. Não foi, no entanto, possível confirmar a sua ligação a práticas de pesca, nem o pressuposto de que a biodiversidade de peixes é maior nas ilhas mais a sul, i.e. longe do principal porto de pesca. Este trabalho contribui para uma descrição detalhada dos habitats marinhos, adequada a usos de gestão e planeamento típicos, nomeadamente a definição de zonas de pesca e monitorização da superfície coralina, contribuindo simultaneamente para o desenvolvimento da aplicação de detecção remota aos campos da biodiversidade e conservação. (Less)
Abstract
The Primeiras and Segundas Archipelago Reserve, located in the waters of northern Mozambique, is the largest marine protected area in Africa, extending over 200 km of coastline. Despite the region’s importance for the local economic, information on the marine ecosystem, notably benthic habitat, is very scarce. Twelve atolls were mapped in the region using object-based image classification of very-high resolution satellite imagery (IKONOS, Quickbird, and WorldView-2). Geographically referenced data on benthic cover and depth were gathered in the course of three fieldwork expeditions covering a total of four atolls and two shallow reef structures. The resulting maps allow the estimation of three distinct types of coral cover (field, patches,... (More)
The Primeiras and Segundas Archipelago Reserve, located in the waters of northern Mozambique, is the largest marine protected area in Africa, extending over 200 km of coastline. Despite the region’s importance for the local economic, information on the marine ecosystem, notably benthic habitat, is very scarce. Twelve atolls were mapped in the region using object-based image classification of very-high resolution satellite imagery (IKONOS, Quickbird, and WorldView-2). Geographically referenced data on benthic cover and depth were gathered in the course of three fieldwork expeditions covering a total of four atolls and two shallow reef structures. The resulting maps allow the estimation of three distinct types of coral cover (field, patches, spurs and grooves); the differentiation of sand, rubble and rock substrate; and the detection of seagrass and brown macroalgae, identifying up to 24 benthic habitats with overall accuracy above 50%. New information indicates the presence of deep benthic cover extending from the atolls, suggesting the need for further research, and supporting current knowledge of the existence of an almost continuous coral reef from Kenya to Mozambique. The results of the analysis of coralline and ichthyological data support the local perception that ecosystems are in decline. It was not possible to verify its connection with fishing practices and the assumption of greater fish biodiversity farther away from the main fishing harbour, i.e. in the southern islands. This work provides a detailed depiction of marine habitats adequate for standard management and planning purposes, namely in the definition of fishing zones and coral cover monitoring, while contributing to the advance of the application of remote sensing to the biodiversity and conservation fields. (Less)
Popular Abstract
The Primeiras and Segundas Environmental Protected Area, located in the waters of northern Mozambique, is the largest marine protected area in Africa, extending over 200 km of coastline. Despite the region’s importance for the local economic, information on the marine ecosystem, notably benthic habitat is very scarce.

Twelve islands surrounded by coral reefs were mapped in the region using very high resolution satellite images and descriptions of the sea bottom gathered in the field. The resulting maps allow the differentiation of sand, rubble and rock on the sea bottom; the detection of different types of maritime vegetation; and of three distinct types of coral cover. Three types of maps were produced, with different detail levels.... (More)
The Primeiras and Segundas Environmental Protected Area, located in the waters of northern Mozambique, is the largest marine protected area in Africa, extending over 200 km of coastline. Despite the region’s importance for the local economic, information on the marine ecosystem, notably benthic habitat is very scarce.

Twelve islands surrounded by coral reefs were mapped in the region using very high resolution satellite images and descriptions of the sea bottom gathered in the field. The resulting maps allow the differentiation of sand, rubble and rock on the sea bottom; the detection of different types of maritime vegetation; and of three distinct types of coral cover. Three types of maps were produced, with different detail levels. The most detailed map has a maximum of 24 classes with an overall accuracy above 50%.

The analysis of coral and fish biodiversity data indicate the local ecosystems decline – both quantity and diversity of coral and fish have registered a decrease when compared to 2006 values. It was not possible to verify that fish stocks are decreasing because of current fishing practices, nor that the southern islands, further away from the main fishing harbour, support larger and healthier fish communities.

Unidentified structures extending from mapped coral were observed, suggesting the existence of a deeper benthic cover. Further research is recommended, as this additional extension of the coral reef systems could prove of great importance for local and regional ecosystems.

With this work it was possible to provide a detailed description of local marine habitats and its coral and fish biodiversity, essential to the Protected Area management and planning, while contributing to the advance of the application of remote sensing to nature conservation. (Less)
Please use this url to cite or link to this publication:
author
Teixeira, Luisa LU
supervisor
organization
course
NGEM01 20142
year
type
H2 - Master's Degree (Two Years)
subject
keywords
fish biodiversity, coral reef, benthic habitats, object-based image classification, very-high resolution remote sensing, geography, physical geography
publication/series
Student thesis series INES
report number
353
language
English
id
7440159
date added to LUP
2015-06-24 09:53:42
date last changed
2015-06-24 09:53:42
@misc{7440159,
  abstract     = {The Primeiras and Segundas Archipelago Reserve, located in the waters of northern Mozambique, is the largest marine protected area in Africa, extending over 200 km of coastline. Despite the region’s importance for the local economic, information on the marine ecosystem, notably benthic habitat, is very scarce. Twelve atolls were mapped in the region using object-based image classification of very-high resolution satellite imagery (IKONOS, Quickbird, and WorldView-2). Geographically referenced data on benthic cover and depth were gathered in the course of three fieldwork expeditions covering a total of four atolls and two shallow reef structures. The resulting maps allow the estimation of three distinct types of coral cover (field, patches, spurs and grooves); the differentiation of sand, rubble and rock substrate; and the detection of seagrass and brown macroalgae, identifying up to 24 benthic habitats with overall accuracy above 50%. New information indicates the presence of deep benthic cover extending from the atolls, suggesting the need for further research, and supporting current knowledge of the existence of an almost continuous coral reef from Kenya to Mozambique. The results of the analysis of coralline and ichthyological data support the local perception that ecosystems are in decline. It was not possible to verify its connection with fishing practices and the assumption of greater fish biodiversity farther away from the main fishing harbour, i.e. in the southern islands. This work provides a detailed depiction of marine habitats adequate for standard management and planning purposes, namely in the definition of fishing zones and coral cover monitoring, while contributing to the advance of the application of remote sensing to the biodiversity and conservation fields.},
  author       = {Teixeira, Luisa},
  keyword      = {fish biodiversity,coral reef,benthic habitats,object-based image classification,very-high resolution remote sensing,geography,physical geography},
  language     = {eng},
  note         = {Student Paper},
  series       = {Student thesis series INES},
  title        = {Exploring the relationships between biodiversity and benthic habitat in the Primeiras and Segundas Protected Area, Mozambique},
  year         = {2015},
}