PLANAQUA - aquatic mesocosms platform


Enclosed Ecosystem Platform

Parent institution: Ecole normale supérieure and Centre national de la recherche scientifique
Active since 2012
Active through 2017-2025

Fields of study

  • Climatology, Climate Change
  • Environmental sciences, Pollution
  • Geology, Sedimentology
  • Marine biology
  • Oceanography, Fishery
  • Microbiology
  • Hydrology
  • Limnology

Contact Information

Lacroix, Gérard

The research infrastructure provides the scientific community with access to a set of experimental equipment with a high level of instrumentation:

(1) Mesocosms with a volume of several cubic meters to several tens of cubic meters, with a high degree of control over thermal gradients and water mixing; mesocosms equipped with beaters to generate waves, making it possible to generate the physical structure of a column of water linked to the mixing of the medium. These facilities, adapted from systems used in fluid mechanics, are the only such facilities anywhere in the world;

(2) Instrumentation including sensors to do measurement of the physical and biological properties of water bodies, probes to conduct non-automated, spot measurements of environmental data, and analytical techniques implemented in the laboratory.

The Location

Country: France

Latitude: +48 17 14.48

Longitude: +2 40 34.64

Nearest town: Saint-Pierre-lès-Nemours

Distance from neaerst town: 3 km

Relevant Research Questions

The infrastructure at the facility combines multiscale (from mesocosms to artificial lakes) experimental platforms, making it possible to explore the following issues: (1) The effects of disturbances due to targeted human activities on the ecology and evolution of populations and on the biodiversity within and between trophic levels; (2) The effects of variations in trophic network structure and the cascade of such effects on the optimisation of energy flux, optimisation of the compromise between fish production and water quality, element recycling and transfer, the resilience and resistance of the system to human disturbance and the capacity of the environment to attain and maintain a good ecological state; (3) Ecological engineering based on the management of trophic networks, to improve the ecological state of environments and enhance ecosystem services; (4) Development of synthetic indicators of the state of the environment and its resilience and resistance to disturbance by human activity; (5) Development of mathematical models of structure and function, for the sustainable management of aquatic ecosystems.


The PLANAQUA platform makes it possible to overcome four major constraints that currently severely limit scientific potential in the domain of aquatic ecology:

(1) Lack of specific tools for addressing certain environmental questions - Very specific systems are required to address certain scientific questions. For example, we offer large mesocosms (15 m3, 10 m long) equipped with beaters to generate waves, making it possible to control the physical structure of the water column.

(2) Inadequacy of the classical scale of experiments - Human activity often leads to a loss of biodiversity, affecting in particular the species at the top of food chains, such as large carnivores. Understanding and managing the consequences of losing these predators from the top of the food chain in ecological systems requires very large experimental systems. Experiments on the functioning of ecosystems involve volumes and levels of biodiversity often well below the complexity of natural environments. Furthermore, these experimental systems do not generally incorporate the physical complexity of the environment or the spatially heterogeneous nature of ecological processes in natural ecosystems. We offer a new experimental tool integrating complexity at the spatial scales of the real world, through a collection of experimental lakes, each with a large individual volume (about 750 m3).

(3) Low level of replication of most experimental infrastructures - The number of independent experimental structures is generally inversely proportional to the size of these structures. The PLANAQUA experimental platform offers a high level of replication for all the equipment proposed, regardless of its size.

(4) Difficulties of understanding ecology and evolution at multiple scales - Both nationally and internationally, there are currently few infrastructures available for studies on ecological systems at multiple levels of integration, from the individual responses of organisms (physiology, metabolism) to the scale of diversified communities in complex environments. This platform offers a wide range of experimental tools from a few liters to several hundreds of cubic meters.


No major technical upgrade to further improve the platform is foreseen since the infrastructure is ending up the construction phase in 2015 with the installation of all sensors, the upgrade of the terrace to host the mesocosms (currently on a temporary terrace) and the construction of a new building (shared with Ecotron IleDeFrance) to host labs and analytical facilities, as well as some growth chambers. Funding is available to cover all these expanses. We plan to install water purification tools (in partnership with the private sector) and invest in new sensors. technical staff has to be strengthened. We will need to recruit a permanent technician.

Experimental Capabilities

Experimental Facilities

Two ponds (each 2000 m2) are available to host in-situ enclosures, rafts with floating emergent macrophytes, or immerged systems for experiments with periphyton. Aquatic microcosms are also available to do experiments on communities of microorganisms in the more controlled environmental conditions of Ecotron IleDeFrance. Instruments, laboratory space and some personnel are shared with the Ecotron IleDeFrance infrastructure.

Experiments duration: Weeks, Months, Years;

Experimental Aerea

Total area: 15000 m²

A fenced study area including a terrace for more than 80 mesocosms (tanks), 1 water storage pond (2000 m2) , 1 water purification pond (2000 m2)

Available area: 7000 m²

Space is available to host for more ex-situ mesocosms (tanks), and 2 ponds (each 2000 m2) are available to host floating mesocosms, water purification systems, or other experimental facilities.

Experimental Unit Size

unit size: 5 m²

The mesocosm area varies between 1 m2 and 10 m2, and their height varies between 10 cm and 150 cm. Moreover, additional enclosures (Area: 0,25 m2 to 18 m2; depth: 0 cm to 350 cm) can be suspended in the water storage pond. The number of these additional experimental units varies accroding to their volume: from 4 large enclosures (50 m3) to 288 small enclosures (0,7 m3).


Replicates number: 12

Cross-Ecosystem Manipulation

Pelagic-benthic or aquatic-terrestrial boundaries

Manipulation Techniques

Temporary storage

  • Dark room
  • Drying oven
  • Freeze drier
  • Freezer
  • Liquid N
  • Refrigerator
  • Other

Available Instruments

  • Fluoroprobe for microalgae characterisation (BBE)
  • BenthoTorch for microphytobenthos characterisation (BBE)
  • Mulitiparametres probe, temperature, conductivity, dissolved O2, pH, total chlorophyll (YSI Exo2)

Electricity available on site.

Distance from Laboratory facilities


Years measured:


Mean Temperature: 11.2 °C

February Mean Temperature: 1 °C

July Mean Temperature: 13.5 °C


Mean Annual Speed: m/s

Max. Annual Speed: m/s

Dominant Direction:


Precipitation type: Rain;

Total annual precipitation: 633 mm

Mean snow cover duration: 0 days

State Variables

Continuously Measured

  • (aquatic) Oxygen content
  • (aquatic) Water temperature
  • Air humidity
  • Air temperature
  • Atmospheric pressure
  • Incident PAR
  • Incident shortwave radiation

Spot Measured

  • (aquatic) Chlorophyl
  • (aquatic) Conductivity
  • (aquatic) Current speed
  • (aquatic) Nutrient levels
  • (aquatic) pH
  • (aquatic) Turbidity
  • Phenology
  • Population densities
  • Species richness
  • Other
  • (aquatic) PAR

Environmental Pressures

Variable Ecosystem Status
CO2 Lake Planned
Warming Lake Active
Precip Lake Active
Hydro Lake Planned
UV Lake Planned
Watereutroph Lake Active
Soilerosion Lake Active
Management - Nutrients (levels or nutrient type) Lake Active
Management - pesticides (or other non-nutrient chemicals) Lake Active
Management - grazing Lake Active
Management - species and/or ecotype combinations Lake Active
Management - traditional (or native) vs. new (or non-native) species Lake Active
Management - other Lake
Habitatfrag Lake Planned
Pests Lake Active
Biodiversity Lake Active

On site Staff and Accomodation

Peak season staff

Up to 15 people

Off season staff

Up to 15 people

Visiting personnel

Up to 15 visitors

Bedrooms available

Up to 36 beds

Showers on site

Showers on site

Laundry on site

Laundry on site