Remote sensing and GIS for Integrated Management of Aquaculture potentialities

摘要

The Aquaculture constitutes a real potential for the Moroccan economic activity related to the sea products. The efficient development and the exploitation of this potential require on the one hand a thorough knowledge of the ecosystems and their potential and, on the other, the setting of management tools allowing a regular follow-up and the orientation of the policies and strategies of development. In this context, and in the framework of the APPUIT project co financed by the European Union, the Royal Centre for Remote Sensing and the National Institute of Haheutic Research carried out a project for the development of operational tools systems for the valorization and the management of the aquacole areas along the Moroccan coast. Thus, a methodology of delimitation of the optimal zones for the installation of aquacole farms was elaborated while being based on the combination of satellite data and in situ measurements realizing an adapted geographical information system. This system currently covers thre sites corresponding to 3 different situations: off shore site of M'diq, the lagoon of Nador and the semi opened bay of Dakhla. This project was proceeded in two phases: 1. The development of a data base, as complete as possible, to improve knowledge on the dynamics of water and its average characteristics in the three sites. In addition to the alphanumeric documents (weather data and socio-economic aspects), the database contains a series of high resolution satellite images (Spot and Landsat) acquired during particular periods corresponding to specific conditions of wind and pluviometry. Two indexes were calculated: an index of turbidity and an index of the sea surface temperature. Moreover, the spatialization of the oceanographic data campaigns, collected through INRH was used to generate layers of information related to the physicochemical aspects of water. Lastly, a hydrodynamic model was built for simulating extreme situations. At this stage, a series of thematic charts were elaborated (maps of the environmental characteristics, maps of risks, maps of water quality). 2. The development of an analysis instrument using tools related to the geographical information systems for the combination of various layers of information in the database. Four types of criteria were retained: environment of the site (Exploitation of maritime space and rivers contributions); the coastal structures (bathymetry and features of the coast); the water quality (anoxia risks and toxic algae) and the dynamics of water (hydrodynamics and exceptional turbidity). The "thresholds of aquacole potentiality" of each criterion has been identified. At the end of this second phase, a model was developed for the automation of the process related to potential zones delimitations for the aquaculture. The use of this model could be extended for prospecting the entire Moroccan coastal zone. Lastly, a user interface "AquaMaroc", was developed to facilitate the use of the database, the consultation of the thematic maps sets and the delimitation of the aquacole zones based on species and breeding techniques.