Line of action:

Status:

Execution date:

General Objective:

Improve the environmental integration of aquaculture developed in Sites of Community Interest and/or Protected Natural Areas.

Specific objectives:

1. Quantify the degree of integration of aquaculture facilities into their environment.
2. Minimization/mitigation of environmental impacts of aquaculture through its integration into natural habitats.
3. Improvement of the integration of aquaculture into the environment, providing added value to the activity, from an environmental perspective.

The project has made it possible to improve knowledge about the environmental repercussions of aquaculture in protected natural areas and the opinion of those responsible for the facilities regarding the possibilities of implementing the mitigation and minimisation measures previously identified has been known.

The project has carried out information collection and environmental monitoring of the environmental effects of aquaculture in 10 land crops and 15 rafts. 80% of the farmers say that they do not know the quality of the water or that they have not taken samples under the rafts, identifying the loss of ropes as the main problem and, at the production level, the speed of the current, toxins, storms and wastewater discharges.

The surveys carried out with the Directorate of the Bay of Cadiz Natural Park and the Territorial Delegation responsible for water quality reflect that the surveillance and investigation of discharges from aquaculture facilities through official analyses is considered essential, thus complying with the discharge inspection plan. Likewise, both entities pointed out that the main incidents are due to the entrapment of birds in the protection nets against ichthyophagous predators and the abandonment of marine farms, with the consequent loss of environmental quality.

To evaluate the degree of integration of mussel farming in the environment, six points have been sampled in three estuaries – two in Andalusia and one in Galicia – in which monthly samples of the water column and sediment have been taken. In the area of Andalusia, two points of the Guadalquivir estuary and three of its bay have been sampled, for two months and every two weeks. The data obtained from the rafts show a lower pH under them, with a lower concentration of oxygen and an increase in the concentration of ammonium, nitrate and nitrite at greater depths. The physicochemical variables in the case of land-based aquaculture facilities are not affected or do not show notable variations, with a clearer evolution for nutrients (ammonium and nitrite).

In view of the results, it can be concluded that the aquaculture facilities evaluated have a good degree of integration into it. In all cases, acceptable levels are observed for all variables, with rapid assimilation of the same. The data obtained in the rafts suggest the use of ammonium, nitrate, nitrite, pH and oxygen as environmental indicators of the integration of mussel farming in the Galician estuaries, due to the degree of sensitivity they demonstrate. In land-based aquaculture facilities, the taking of indicators will depend on the area.

A good practice guide has been designed with nine minimisation and mitigation measures and six indicators for aquaculture facilities in earthen ponds, in addition to another nine measures and two indicators for mussel raft farming facilities.