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The Rias Baixas , owes it’s high biological productivity to it’s unique geographical location. To it’s hydrodynamic characteristics as well as the particular shape of its layout. Finally to the acute timing in the diverse cycles that take place: Physical, Chemical, Geological and Biological. Thus, this semi-closed spaces and of high ecological values are very vulnerable to the atrophic changes, of which contamination and earth filling and moving are uppermost factors, since any change would break the cycles and disrupt the balance.
These particulars render human intervention that would be acceptable in open seas absolutely unacceptable inside the Rias. Unacceptable and dangerous.
| The term “RIA” is universally accepted and recognized as different from “Bays” and “Estuaries” which in itself is a recognition of it’s singularity. |
The fragility of these peculiar spaces along with their fauna and vegetation, the recreational possibilities, fish and shellfish production as well as the future possibilities for development of water cultivation, are important factors to take into account when faced with different initiatives that could endanger actual and future possibilities for development and growth. Objective observation of the immediate and long term impact of the intervening factors is necessary and in case that is proven to be indispensable, the application of the measurements to ensure the lowest possible impact in the environment is also important.
On the other hand, ecological and biological enclaves need protection and careful use of their resources, following the protection tendencies of all developed countries and specifically the mandates of the EU legislation as of Spanish legislation and particularly Galicia’s legislation
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The Ria de Vigo, is a physical-biological functional unity (related to the nearest geological platform) and as such is affected as a whole by any disruption, localized as it might be. |
This is the reason why an analysis of the total impact in the zone must be made, the impact in space and in time, when contemplating new developments. The repercussions that a filling project might have, ought to be carefully considered in reference a previous aggressive works like the ones done in Bouzas and Berbés, in reference at the projected work itself and lastly considering the possibilities of future works.
All said, inspires the consideration of a legislation that clearly defines the proper uses of the coastline. Establishing objectives that are the result of thorough debates, where the necessities and opinions of the inhabitants and beneficiaries are duly considered and respected. In this case, an occupational limit of the use of the waters has to be firmly established in order to avoid the transformation of the Ria in a regular port canal
The most important of these effects can be grouped in the ones produced by the earth fillings and dredging done to the coastline and underwater.
Aesthetic and negative landscaping impact.
Seabed habitat loss.
The disappearance of all organisms in millions of cubic metres of water and sediments that have been altered by the fillings.
Mortalities, in the zones next to the work, of biota marine with reduced or null mobility or that it does not have or it has little developed the reaction of “escape”.
The density of the solid dust from the fillings suspended in the water impedes the indispensable energy from light necessary for photosynthesis, meaning the primary production, thus diminishing the biomass that is so made in the Ria, with the economic and environmental effects that this implies.
The introduction of refuse and lost materials suspended in the water, besides the physical effects on the respiratory system of the species, affects the metabolism of the purifying organisms that have to excrete the non adsorbed particles, with the resulting energetic overuse and lack of growth.
In case that the materials used were not the most adequate, is a possibility that arriving in the sea, these materials could liberate particles in suspension that would endangered the whole environment.
Diminution of the concentration of oxygen
Destruction of the benthonic communities that occupy the removed sediments.
Release of the contaminants associated to the seabed that are thus mixed in the food chain, raising their levels considerably and passing them on to the consumer, rendering the product inadequate for marketing by the UE and Spain legislations.
Chemical contaminants at certain concentrations produce a negative impact in the ocean’s environment at very many levels. Individual organisms, communities, populations and ecosystems, altering the reproduction chain and provoking among other things, biochemical and physiological changes. This affects have more impact in less developed organisms, so phito and zooplankton, eggs, larva and juveniles are the most affected by the phenomenon, and this produces a general diminution of the biomass in every link of the food chain, with the inevitable repercussion on the local economy.
