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There are many interactions between fisheries,
including aquaculture and capture fisheries as well
as their intermediate forms in freshwater and
marine environments, and other uses of the aquatic
systems such as agriculture, flood control, power
generation, tourism, mining, transportation, land
development (e.g. housing), and urban and
industrial effluent disposal.
Synergistic interactions
Synergistic interactions between fisheries and
agriculture are primarily derived from the
recycling of livestock or farming wastes and
nutrients and optimal use of scarce land and water
resources. In aquaculture, the active search for
synergies has led to a number of development and
management concepts such as Integrated
Agriculture-Aquaculture (IAA), Integrated
Irrigation-Aquaculture (IIA), as well as to
livestock-fish or rice- fish production systems.
These synergies have been enhanced by improving the
use of water and reducing agricultural impacts on
aquatic systems, e.g. through the Integrated
Pest Management concept (IPM). These
improvements have been beneficial in improving
water and fish quality and productivity. Unexpected
synergies have also been detected in marine
fisheries where the nutrients of continental origin
(e.g. phosphates, nitrates), often a source of
eutrophication and red tides, are believed to have
increased productivity (e.g. in the Mediterranean
and the North Sea).The development of reservoirs
and other small-water bodies for agricultural and
other purposes offers additional opportunities for
both aquaculture, culture-based fisheries through
stocking, and capture fisheries.
Antagonistic interactions
Antagonistic interactions between agriculture
and fisheries occur where these two sectors compete
for the same kinds of resources, especially land
and water, where rising productivity in one
production system leads to reducing productivity in
the other. For example, bad farming practices and
deforestation impact on aquatic habitats and water
resources - and therefore on fishery resources
productivity and quality - through erosion,
siltation, pollution and eutrophication (and red
tides) resulting from excessive use of pesticides
and fertilisers. Similarly, extensive saltwater or
brackish water culture on coastal land areas
affects the quality of soils (salinization, water
logging) and the quality and level of the water
table. Dams established for the purpose of
irrigation, flood control or energy production
impair fish migration and reproduction routes and
change the qualitative nature of the habit which in
turn influences the aquatic communities, e.g.
changing species composition from riverine to
lacustrine species. Efficiency in the use of water,
primarily fresh water, and land resources is
becoming of central importance to sustain increases
in fisheries so as to provide for rural village
communities and supply urban areas with the needed
quantity, quality and variety of food. In many
areas where human activities have rapidly expanded
during the last decade, there is increasing
pressure on limited land and water resources.
There are also interactions between capture
fisheries and aquaculture. Development of
aquaculture may adversely impact capture fisheries
through habitat change associated with farming
systems or impacts of introduced species. There is
competition for space between the production
systems; for habitat and resources between wild and
farmed species; for the market between respective
harvests and products; for wild seeds. Pollution
from aquaculture may also be a problem. On the
other hand, aquaculture may provide alternative
employment in overexploited areas or additional
resources for fishing through enhancement, and may
be an important alternative source of fish for
rural communities thus reducing the fishing
pressure and helping in the rehabilitation of wild
fish stocks.
The negative sides of these numerous
interactions is progressively being recognised by
Governments and industry and integrated management
of natural resources is the strategy of choice to
improve efficiency despite obvious implementation
difficulties. The integrated management of
watersheds, river basins and coastal areas (and of
productive ecosystems in general) aims at managing
sectoral components as parts of a functional whole.
The overall objective of better integration between
fisheries and other sectors in policy development
and management is to maximize synergistic
interactions and minimize antagonistic ones.
Awareness of inter-sectoral dependencies,
through the environment and the global economy, is
rapidly rising, stimulated inter alia by growing
media coverage of ecological catastrophes, advances
in data processing and information technology,
development of ecological economics, increased
mobilisation of social forces through NGOs
communications. The abilities of local communities
to participate in information gathering, analysis,
decision-making and enforcement is better
recognised together with the need to involve them
directly in decisions regarding common property
resource use. All of this has created favourable
conditions to fully realize the benefits of better
integration between fisheries and agriculture as
well as of these sectors with the rest of the
economy.
Numerous difficulties remain on the way towards
better integration. Among these:
- the technical difficulty of integrated
development planning;
- the political and economic difficulty of an
equitable allocation of resources;
- the organisation of a balanced leadership of
the interaction between sectors;
- the decentralisation of rights and
responsibilities;
- the development of the human resources
necessary for effective decentralisation;
- the cost of better understanding of the
ecosystems functioning and resilience;
- the application of the precautionary
approach when information is lacking;
- the development of integrated indicators of
sustainability.
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