The nature park at the CSG is French Guiana in miniature

The grounds of the Guiana Space Centre (CSG, Centre Spatial Guyanais) extend from Kourou in the West across to Sinnamary in the East, covering an area of about 70,000 hectares. In addition to its space-related activity, this is also an outstanding natural area due to the great variety of landscapes which can be found here. The different landscapes, which connect the ocean to the evergreen tropical forest, provide an almost exhaustive illustration of the ecosystems to be found in French Guiana: rocky islands at sea, mangrove forests, forests on the sandy coastal strip, dry savannah, freshwater marshes, woody savannah, the flooded forest with moriche and açai palms, inland forest growing on ferralitic* soils, rivers and riverside forest, and inselbergs.

The natural variety of the biotopes, in conjunction with the implicit protection accorded to the site, means that it has been possible to maintain this remarkable biodiversity. Several sensitive ecological zones (especially pripris and savannah) have been placed on the ZNIEFF* inventory.

Forty-eight species of mammals, including the jaguar (Panthera onca) and giant anteater (Myrmecophaga tridactyla), are regularly spotted in the leisure zone (golf course). With regard to amphibians and reptiles: 5 species of lizard have been found, 10 species of snake, 2 species of caiman, 3 species of tortoises and 21 species of amphibians. Birds are also very well represented, including waterbirds, waders and ibis.

The CSG – an industrial site that is monitored and measured

The SPPPI (Secretariat for the Prevention of Industrial Pollution) was set up in July 1997 by a Prefect’s decree following on from the Ariane 501 accident in June 1996. It unites all the local bodies – the National Centre for Space Study (CNES, Centre National d’Etudes Spatiales), state departments, local authorities, industrialists, environmental protection associations, the media, experts, and so on – with a common interest in industrial environmental issues. The aim is to provide answers to the questions that people are asking about the risks of and pollution caused by space sector activity.

The SPPPI currently relies on two specialised committees: an “environment, health, and launcher” committee and a “soil risk” committee.

The results of the Environmental Measurement Plans (PME, Plans de Mesures Environnement) are presented to the “environment, health and launcher” committee. These measurement plans are drawn up by engineers at the CNES and systematically carried out under their responsibility during launches so as to assess the impact on the local environment.

The various aspects which are studied include taking measurements of the air, water, vegetation, and both the land and aquatic fauna. The results show that the impact is local and limited to within a radius of about one kilometre of the launch site.

When an ARIANE 5 rocket is launched, a cloud is formed made up of products produced by the combustion of the propellant (hydrochloric gas and particles of alumina). As a large quantity of water is projected onto the launch pad, this combustion cloud becomes heavier and many of the pollutants fall back to the ground in the area surrounding the launch site. The cloud, once stabilised at an altitude of between 1000 and 1500 metres, is then affected by various different winds. The combustion products are dispersed into the atmosphere and can no longer be measured when they have returned to the ground.

This measurement plan, implemented for Ariane 5, will also be used for the new Soyouz and Vega launchers.

Aquatic fauna and the Hydreco studies

Fish inventories, carried out at the CSG, show a great biodiversity of aquatic fauna with 73 species of fish identified in Malmanoury creek and 53 in Karouabo creek. This aquatic fauna provides an indicator for environmental monitoring of the CSG.

As part of this, the Hydreco laboratory is carrying out studies of the fish and aquatic invertebrates, aiming to take samples of all of the populations present in the creeks.

The method used for fish is surface gillnets as this has the advantage of being standardised and reproducible. Two sets of 10 nets of different size mesh, ranging from 10mm to 70mm but with identical surface areas (50m²), are set up in the evening along the banks where the fish find food, hiding places and calm zones for breeding. They are then inspected the following morning and various measurements are made on each individual captured (size, weight and gender) and samples taken (stomach and flesh) to determine their diet and the level of various metals such as aluminium.

Aquatic invertebrates are the first organisms to be affected by any pollution of the aquatic environment – be it due to human activity or not – and act as a reliable indicator of the water quality. The SMEG (Average Score of Ephemera of French Guiana, or Score Moyen des Ephémères de Guyane) is established for each biannual sample. This score has been monitored, corroborating fish observations since 1998, indicating that Ariane 5 has no major impact on the aquatic environments of the CSG. But the environment and water populations are increasingly subject to climate change. At least another thirty or so samples will be required to confirm this.

Birds and the ECOBIOS studies

Over the past 15 years, particular attention has been paid to birds at the CSG which is managed by Oliver Tostain, the ornithologist who runs the ECOBIOS consultancy in Cayenne. The diversity of habitats found at the space base is illustrative of all of French Guiana’s biotypes and means that birds can be used as a way to describe the quality of ecosystems, as an indicator of the sensitivity of fragile and small populations to industrial activity, and, finally, as a biological marker for any functional disruption that may be caused by the rockets themselves when launched.

Alumina measurement on feathers.

During the first ten years of the Ariane 5 programme, research was carried out so as to detect the geographical extent and impact of alumina particles from the combustion of boosters on the launcher at take off. Dust was collected on the feathers of wild birds which were captured and then released in the biotopes above which the cloud dispersed. Whilst there was an increase in the alumina particles in the ecosystem after a launch, this was never detectable at a distance of more than five or six kilometres from the launch sites. Beyond this, it blends into the naturally occurring background levels of this element. Furthermore, no direct impact was ever observed in