Environmental impact of aquaculture

234 Pages·2011·9.81 MB·English

His Majesty Sultan Qaboos bin Said
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SSUULLTTAANNAATTEE OOFF OOMMAANN - -M MININISISTTRRYY O OF FF IFSIHSHEREIREISE SW WEAELATLHT H- A- AQqUuAaCcUuLlTtUuRrEe CCEeNnTtRrEe
ATLAS OF SUITABLE SITES FOR AQUACULTURE PROJECTS IN THE SULTANATE OF OMAN
Foreword
Aquaculture is one of the fastest growing food production systems in the world and has gained considerable
attention as a significant contributor to socio-economic well-being of developing nations (FAO 1997). With particular
reference to developing countries, aquaculture development has been predicted as one of the major structural shifts
in outlook for fisheries in 2020. With the adoption of sophisticated technologies and science-based policies, and
under the effective regulatory mechanisms the development of aquaculture industry in the Sultanate of Oman has
the potential to make significant contribution to the socio-economic well-being of the community including food
security. Complementary to its present position as net exporter of fish products, the responsible development and
management of aquaculture could provide the Sultanate with a distinct competitive edge in the international and
regional markets.
Realizing the socio-economic potentials, the Ministry of Fisheries Wealth has developed this Atlas which is intended
to be a future reference work on the development of aquaculture industry. The present Atlas is also expected to be of
practical use to the scientific and educational communities, policy and decision-makers, and commercial enterprises.
The Atlas comprises comprehensive information on various key themes along with satellite images essential to the
development of aquaculture industry in the Sultanate. Among these themes are: a) importance of aquaculture site
selection, b) oceanographic and environmental descriptions of the nation’s coastline using satellite imagery, c) brief
history of aquaculture production, d) identification of potential constraints, e) types of aquaculture and species
suitable for Oman, and f) region-specific oceanographic features, environmental characteristics and constraints, and
survey results of various factors.
The successful development of a sustainable and competitive aquaculture industry in the Sultanate of Oman
will depend on a number of critical factors including, amongst others: a) government commitment and support,
b) adoption of effective regulatory guidelines, c) coordination and partnerships among key stakeholders, d) adequate
investment in high priority aquaculture research, education and training programs, and e) public awareness.
Finally, it is hoped that the Atlas will help identifying information and data gaps so that additional research and
appropriate planning for resources could be done in the future to close the gaps.
Ministry of Fisheries Wealth
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SULTANATES OUFL TOAMNAANT E- MOFI NOIMSTARNY O- FM FIINSHISETRRIYES O WF EFAISLHTHER -I EASQ WUEAACLUTLHT U- RAEq CuEaNcTuRlEture Centre
ATLAS OF SUITABLE SITES FOR AQUACULTURE PROJECTS IN THE SULTANATE OF OMAN
SULTANATE OF OMAN
MINISTRY OF FISHERIES WEALTH
Atlas
of Suitable Sites for Aquaculture Projects
in the Sultanate of Oman
Disclaimer
Unless otherwise stated specifically, the Oman National Hydrographic office does not assume any legal liability from any entity whatsoever
for any data or hydrographic information have been included and disclosed in this Atlas. This Atlas was examined and approved and it is
not recommended to be used for navigation and not an authority on international boundaries.
The Atlas project was envisaged and funded by the Ministry of Fisheries Wealth. The Atlas document was prepared by Middle
East Scientific Equipment Corporation LLC (MESEC), Sultanate of Oman and their consulting partners
IDDE, France and CREOCEAN, France.
2010
Registration No. 123/2010
SULTANATE OF OMAN - MINISTRY OF FISHERIES WEALTH - Aquaculture Centre
Objectives 8
Introduction 9 - 11
The importance of the site selection 12
Oceanographic and environmental description of the coast of Oman 13
Meteorology 13
Precipitation 13
Temperatures 14
Solar radiation and clearness index 15
Wind conditions 16
Physical Oceanography 20
General characteristics of the north-western Indian ocean 20
Hydrodynamics 22
Hydrology of coastal waters 29
Synthesis on hydrodynamics and hydrology of coastal waters 44
Waves 45
Biological Oceanography 50
Turbidity, nutrients and phytoplankton 50
Seagrasses and algae 55
Mangroves 56
Corals and other marine invertebrates 56
Marine turtles 58
Coastal and marine birds 60
Coastal protected areas 60
Aquaculture Production In Oman 62
Methodology 64
Identification Of The Constraints 66
Physical and environmental constraints 66
Biological constraints 69
Logistical constraints 71
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SULTANATE OF OMAN - MINISTRY OF FISHERIES WEALTH - AQUACULTURE CENTRE
ATLAS OF SUITABLE SITES FOR AQUACULTURE PROJECTS IN THE SULTANATE OF OMAN
Different Types Of Aquaculture Suitable For Oman 72
Cage Farming 72
Site selection 73
Traditional cage farming 73
Immersed cage farming 74
Cages supplemented with aeration/oxygenation 74
Land - Based Aquaculture 76
Pumping systems 76
Earthen ponds 78
Raceways 80
Recirculating aquaculture system 81
Restocking Programmes 82
Physical And Environmental Atlas 84
Region I: Rakhyut To Sawqrah 85
Oceanographic characteristics 86
Environmental constraints 88
Seawater survey results 89
Soil survey results 91
Regional ports, public and investment services 91
Aquaculture survey 92
Cartographic illustrations 94
Region Ii: Sawqrah To Madrakah 116
Oceanographic characteristics 117
Environmental constraints 119
Seawater survey results 120
Soil survey results 122
Regional ports, public and investment services 122
Aquaculture survey 123
Cartographic illustrations 124
Region Iii: Gulf Of Masirah 132
Oceanographic characteristics 133
Environmental constraints 135
Seawater survey results 136
Soil survey results 138
Regional ports, public and investment services 139
Aquaculture survey 140
Cartographic illustrations 142
SULTANATE OF OMAN - MINISTRY OF FISHERIES WEALTH - AQUACULTURE CENTRE
ATLAS OF SUITABLE SITES FOR AQUACULTURE PROJECTS IN THE SULTANATE OF OMAN
Region Iv: From Masirah To Ras Al Had 156
Oceanographic characteristics 157
Environmental constraints 159
Seawater survey results 160
Regional ports, public and investment services 162
Aquaculture survey 163
Cartographic illustrations 164
Region V: Ras Al Had To Muscat 172
Oceanographic characteristics 173
Environmental constraints 175
Seawater survey results 176
Soil survey results 178
Regional ports, public and investment services 178
Aquaculture survey 179
Cartographic illustrations 180
Region Vi: Muscat To Shinas 186
Oceanographic characteristics 187
Environmental constraints 189
Seawater survey results 190
Soil survey results 192
Regional ports, public and investment services 192
Aquaculture survey 193
Cartographic illustrations 194
Region Vii: Musandam 208
Oceanographic characteristics 209
Environmental constraints 211
Seawater survey results 212
Regional ports, public and investment services 216
Aquaculture survey 217
Cartographic illustrations 218
Recommendations 224
References 230-234
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SULTANATE OF OMAN - MINISTRY OF FISHERIES WEALTH - AQUACULTURE CENTRE
ATLAS OF SUITABLE SITES FOR AQUACULTURE PROJECTS IN THE SULTANATE OF OMAN
Objectives
The principal objective of this Atlas is to facilitate the implementation of new aquaculture projects in the Sultanate of
Oman with due consideration to the suitability of specific environmental conditions and sustainability. Aquaculture
in Oman can take advantage of the nation’s 3,165 km of coastline. This Atlas focuses on identifying potential sites and
describing possible aquaculture systems that can be deployed along the Omani coastline.
The key development factor for aquaculture is the recognition and development of suitable sites for aquaculture
system to be implemented. Aquaculture development should take into consideration the biological requirements of
candidate species to be cultured and their appropriate match to prevailing environmental conditions. Secondly the
typology of the recommended aquaculture system should provide the optimum solution for establishing aquaculture
at a suitable site or area either at sea or on land. The Atlas offers an overview of different types of aquaculture system
suited to various marine environments. The selected production systems are considered to have least environmental
impact when better management practices are employed.
Also a survey was carried out along Oman’s coast in order to identify key problems to development of sea-based
aquaculture (cage farming), namely the occurrence of harmful algal blooms (HABs). HABs have been reported along
the coast of Oman for many years but their recurrence had caused massive losses from existing facilities in recent
years.
This phenomenon may also have an adverse impact on the land-based farms if not taken seriously into account
during the design and planning phases of production systems. Some of the aquaculture systems presented in the
Atlas aims at providing solutions to the HAB problem, offering a more sustainable approach to sector development.
Finally, the potential for aquaculture production in the Sultanate is estimated on a regional and per species basis.
Tables incorporated into the text provide an indication of possible production capacity following full development
of the sector. This goal may be achieved in a few years under strong financial support from both public and private
sectors, acting individually or in unison.
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SULTANATE OF OMAN - MINISTRY OF FISHERIES WEALTH - AQUACULTURE CENTRE
ATLAS OF SUITABLE SITES FOR AQUACULTURE PROJECTS IN THE SULTANATE OF OMAN
Introduction
The coast of Oman is surrounded by the Arabian Sea to the south and by Sea of Oman to the north. This coastline can be
divided into two geographical regions which are distinguished by their hydrodynamic and hydrological characteristics.
This feature is detailed within the present report.
The Sea of Oman is positioned between 22° and 26° N and 56° and 60° E. In its northwestern part, it is connected to
the Arabian Gulf by the Strait of Hormuz; its southern part opens into the Indian Ocean. The southern coast of Oman
lies between 18° and 22° and 53° and 60° E and abuts the Arabian Sea which corresponds to the north–western Indian
Ocean.
The southern Arabian Gulf has been the
focal point for human settlement for well
over 8,000 years (Thomas et al., 1988;
Macchiarelli, 2005). During this time of
coastal colonization, the bounty of the seas
represented a vital source of food and this
marine dependency has been established
by examining and comparing ancient teeth
samples from the Arabian Peninsula. The
odontological evidence strongly points to a
predominantly fish and mollusk-based diet
for coastal Omanis (Kunter, 1996; Littleton
and Frohlich, 1993), a conclusion that is
further strengthened by the discovery of
large shellfish middens scattered throughout
the country. For over 80 centuries, the people
of Oman have thus maintained a close
association with the maritime environment,
perhaps first as marine hunter-gatherers and
later as active fishers. Even given this long
Figure 1.1 - Map showing deliniations of the Arabian Gulf, Strait of
marine association and fishing tradition,
Hormuz, Sea of Oman & Arabian Sea
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SULTANATE OF OMAN - MINISTRY OF FISHERIES WEALTH - AQUACULTURE CENTRE
ATLAS OF SUITABLE SITES FOR AQUACULTURE PROJECTS IN THE SULTANATE OF OMAN
Ras Al Had
Figure 1.2 - Geographic and bathymetric map of the Sea of Oman and north-western Arabian Sea. (Pous, 2005)
other than small trading of salted and dried fish to interior settlements by Bedouin, seafood was, until 1970 the main
part of national economy. When oil revenue became the mainstay of economy, wise investments were made to develop
national infrastructure and, as a part of this process, the Fishery Subsidy Project was set up to provide direct subsidy
for the purchase of new boats and outboard engines (Ministry of Agriculture & Fisheries, 1990). The introduction of
modern technologies prompted development of a vibrant and contemporary fishing sector (Al-Oufi et al., 2004). Today,
Oman’s fisheries landings account 34% of the agricultural economy and provide employment for 2.4% of the nation’s
labor force (FAO, 2008). In 2009, the value of the combined artisanal and commercial fish landings was estimated at
around OMR 104 million. A characteristic of the artisanal fishery is its diversity, not only in terms of gears used and
species taken, but also in manning (Stengel and Al Harthy, 2002). Oman’s artisanal fishing grounds are used by full-
time, part-time and infrequent fishers which, in the case of certain shellfish and holothurian stocks, include women.
Globally speaking, bathymetry of Oman coastal waters is mainly characterized by a narrow continental shelf on the
Arabian Sea coast, especially in its south-western part where the isobath 200 m is very close to coastline. The continental
shelf is also narrow along the Sea of Oman coast but the continental slope is gentler.
Perhaps because of the diversity and numbers of people engaged in fishing, by the late 1990s indications of
overexploitation of various marine resources were detected. This included sharks (Al-Kharusi et al., 2002), demersal
and pelagic species (Al-Oufi et al., 2002; De Rodellec et al., 2002) and shrimp. The downward trend in fish catch and
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