Know more

Our use of cookies

Cookies are a set of data stored on a user’s device when the user browses a web site. The data is in a file containing an ID number, the name of the server which deposited it and, in some cases, an expiry date. We use cookies to record information about your visit, language of preference, and other parameters on the site in order to optimise your next visit and make the site even more useful to you.

To improve your experience, we use cookies to store certain browsing information and provide secure navigation, and to collect statistics with a view to improve the site’s features. For a complete list of the cookies we use, download “Ghostery”, a free plug-in for browsers which can detect, and, in some cases, block cookies.

Ghostery is available here for free:

You can also visit the CNIL web site for instructions on how to configure your browser to manage cookie storage on your device.

In the case of third-party advertising cookies, you can also visit the following site:, offered by digital advertising professionals within the European Digital Advertising Alliance (EDAA). From the site, you can deny or accept the cookies used by advertising professionals who are members.

It is also possible to block certain third-party cookies directly via publishers:

Cookie type

Means of blocking

Analytical and performance cookies

Google Analytics

Targeted advertising cookies


The following types of cookies may be used on our websites:

Mandatory cookies

Functional cookies

Social media and advertising cookies

These cookies are needed to ensure the proper functioning of the site and cannot be disabled. They help ensure a secure connection and the basic availability of our website.

These cookies allow us to analyse site use in order to measure and optimise performance. They allow us to store your sign-in information and display the different components of our website in a more coherent way.

These cookies are used by advertising agencies such as Google and by social media sites such as LinkedIn and Facebook. Among other things, they allow pages to be shared on social media, the posting of comments, and the publication (on our site or elsewhere) of ads that reflect your centres of interest.

Our EZPublish content management system (CMS) uses CAS and PHP session cookies and the New Relic cookie for monitoring purposes (IP, response times).

These cookies are deleted at the end of the browsing session (when you log off or close your browser window)

Our EZPublish content management system (CMS) uses the XiTi cookie to measure traffic. Our service provider is AT Internet. This company stores data (IPs, date and time of access, length of the visit and pages viewed) for six months.

Our EZPublish content management system (CMS) does not use this type of cookie.

For more information about the cookies we use, contact INRA’s Data Protection Officer by email at or by post at:

24, chemin de Borde Rouge –Auzeville – CS52627
31326 Castanet Tolosan CEDEX - France

Dernière mise à jour : Mai 2018

Menu Logo Principal

Home page


All news

Christmas paper

"Local human pressures influence gene flow in a hybridizing Daphnia species complex", by Alric et al, in Journal of Evolutionary Biology
Read more
Léman, hiver 2009

New Year's Paper

Reconsidering the drivers of lake CO2 over time...
Read more

Publication of a review paper on the results of the overall IPER-RETRO research program

A synthetic review of all the results and papers from the IPER-RETRO project published in July 2015 in 'Frontiers in Ecology and Evolution"
Read more

IPER-RETRO Research: spotlight in EOS

Past Phosphorus Runoff Causes Present Oxygen Depletion in Lakes
Read more

IPER-RETRO as Keynote of the session 'From the Holocene to the Anthropocene: the history of human-environmental interactions' at the COP 21 Scientific conference

IPER-RETRO review invited to present at the CFCC
Read more

New papers on line

New papers, on line
Read more



Studies covering long-term climatic variability have shown that the similar climate change can lead to completely opposite consequences on lake ecological status, depending on its location and morphological characteristics. Our knowledge of climate influences on lake ecology is then considerably hampered by the complexity of the pathways under which climate can act on these ecosystems. Indeed, such a singularity of lake responses to climate results from the fact that the different climate components can affect the lake directly, through modifications of the water column physical, chemical and biological properties, but also indirectly through their impacts on the watershed characteristics and subsequent inputs to the lake (Leavitt et al, 2009). Depending on the lake context, one pathway or the other shall predominate, leading to a lake-specific response to climate change.
Since local anthropogenic pressures exert strong structuring effects on lakes or their watersheds, our assumption in this work is that the impact of climate change on lake ecological and geochemical processes will depend on the intensity of local pressures.
We use, for that purpose, a set of three peri-alpine lakes (Annecy, Bourget, Geneva) exhibiting rather similar morphologies and submitted to the same climatic variability. These lakes have undergone, over the last century, similar local forcings (changes in nutrient inputs and fisheries management practices) but with varying intensities.
The first step of the program has been dedicated to the paleolimnological reconstruction of the lakes ecological and geochemical processes over the last 150 years. To reach a large picture of ecological processes, we implemented the classical paleolimnological approach by several new proxies developed within the program (molecular methods for microbial diversity, stable isotope analysis for food web structure and geochemical indicators of anoxia). We could then achieve a holistic and ecosystem-wide view on how these three lakes changed over the last century.
A second, on-going step consists in hierarchizing the drivers of the ecological changes observed over time. For instance, detected changes in food web structure resulted from the interactions between local and global forcings in all cases. However, using adequate models, we could show that climate impacts on food webs increased with the intensity of local stressors, and especially eutrophication. We could also detect the appearance of lake bottom anoxia, a major symptom of ecosystem degradation, from the 1950’s and its persistance since then, in spite of undertaken remediation measures. The contribution of climate change to the persistance of lake bottom anoxia was shown to be uneven between the three lakes.
The take-home message is then that morphologically comparable ecosystems under similar climate forcing are not evenly sensitive and these differences in vulnerability to climate warming depend on local stressors. Our conclusion fuels the debate about the predictability of the impacts of climate change on ecosystems and emphasises that local forcings should be considered when extrapolating from one site to another.

This program was funded by the "Vulnérabilité, Milieux, Climat et Sociétés" call for proposals from the French National Research Agency.

Read more