1

UMR Carrtel

Research Center on Trophic Networks andLake Ecosystems

- Unit- Lake Observatory- Some results

Bernard MONTUELLE

2

1-1. Global scientific context

functionning of alpine lakes ecosystems related to their watershed and the atmosphere

the effect of drivers , especially in the context of the present re-oligotrophisation dynamics and the climate change. 

Integers the global change issues

Land U

sesP

ollutions

RegulationsStandarts

Climate

- 3 Sub systems and specific functionnings

-Fluxes and internal exchanges

- External drivers and exchanges

Lake

Water uses(fishing, recreational…)

flux./proc.

Flux./proc.

Watershed- rivers

ACTIVITES HUMAINES

soils

Flux./proc

Atmosphere

T, light, deposits,

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Issue 1: Fluxes and processes at the interfaces

Issue 2: Structuring ecological processes

Issue 3 : Quality and management of the lakes and their ressources (environmental drivers changes)

► biogeochemical hot spots► upstream-downstream fluxes ► fluxes modelling

Lac

usages(pêche…)

fluxflux

Bassin versant - affluents

sols

flux

ATMOSPHERE

T, lumière, dépôts

► measurements► quality indicators► helping managers

Biodiversity

Functions

Structure

3 organisation

levels

► role of biodiversity► biological models►productivity- trophic fluxes►ecotoxicology

1-1. Global scientific context

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2 – Operational issues

PAST status Today status Surveys

and data

LEMAN MESOTROPHIC(from1957)

CIPEL

BOURGET MESOTROPHIC(from 1990)

CISALB

ANNECY OLIGOTROPHIC OLIGOTROPHIC(reference)

(from 1980) SILA

Annecy

Bourget

Léman

Re-oligotrophisation and climate vs fishing

Micropollutants (new or old)

Changes of land uses (practices..) Gobal management (lake+watershed)

Current questions(Ministery –Water Agency –Lake managers)

1950-1980* eutrophication

1980-1990: *control of P fluxes* re-oligotrophication

Taking into account the managers/stakeholders questions

Lake uses:- fishing- water resources- recreational- ecological services

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Head (1)

Watershed group:Watershed,

fluxes, sediments(5)

BIO-FEEL group:Biodiversity,

Functions and Evolution of Lake Ecosystems (5)

Environmental Research Observatory

Technical group (University of Savoie(3 )

Chemistry lab(4)Biodiversity and Molecular Biology Group (5 )

Outdoor experimental devices

(2)

Sampling group(5)

Secretariat andAccounting (2) Resource Center (1) Computing and database

(2) Workshop

(2)

45 full time 20 scientists 10PhD + post

3.1 The Unit and it’s scientific topics Thonon

Chambéry

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3.2 The Unit and it’s scientific topics

Group WaterShed: Transferts and functionning at interfaces

Main topic: The Watershed as a transfer system to the lakes♦ Functional spatialization of watershed ♦ Fluxes from terrestrial to aquatic ecosystems

Lac

usages(pêche…)

fluxflux

Bassin versant - affluents

sols

flux

ATMOSPHERE

T, lumière, dépôts

Group » Biodiv- Funct »: Ecological processes and biological responses

Main topic: « Functionning and regulation of trophic networks» ♦ Pelagic communities ♦ Functional role of biodiversity

Group « Fish & Ecotox »: Environmental quality and Resources management

Main topic: « Halieutic and stocking »♦ Drivers of fish productivity (lakes and rivers)

Main topic: « Algal and microbial ecotoxicology (biofilms, ..) » ♦ Contamination dynamics and impacts (pesticides)

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ACADEMIC (60 to 70 %)

► Producing generic knowledges (25 internat. papers/year + books)

► Building environmental Observatory: Alpine Lake Observatory

► Contributing to scientific networks

RESULTS for SOCIO-ECONOMIC Instances and Public stakeholders (20%)► Expert reports (Soils, Taxonomy), study reports, assessments,..► Decision-making assistance, developing partnerships (lakes, fishing, agriculture),producing documents ( technical guides, reports, …)

RESULTS for education and training for research (<10%)►University and engineer Schools.►PhD formation►PhD: ± 3/year

3.3 The Unit and it’s scientific topics

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OBJECTIVES  • Organize data collection, their storage, their use and their accessibility• Scrutinizing, understanding and modelling the trajectories and the ecological mechanisms controling the lake systems exposed to changes in anthropic and climatic pressures, at a 10 years time steps ».

The Environmental Research Observatory « Alpine Lakes »(LTER)

Le Bourget Mesotroph

(re-oligotrophisation)

Léman Mesotroph

(re-oligotrophisation

Annecy Oligotroph

±1950

± 1980

± 1990

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Observatory

Long term limnology

Short and mid term processes

Associated projects

- Long term surveys- Physicochemical and biological processes controling water quality - Ecological trends- Consequences of global change

- Small mountains lakes- Micropollutants ecodynamics

> 10 years

1< < 10 years

1010

Parameters - Physico-chemistry - Phytoplancton- Zooplancton - Bacterio & virioplankton - Chlorophyll- Primary production- Probes- Weather - Fish catches (annual)

Information Systems – data base

data

Database

Public access

11Multiparameters Probes

1920 1960 1970 1980 1990 2000 2010

Perch O+

Zooplancton (net 2)

Bacterioviroplancton

Primary production

Meteo data

Flurorometric probe

Fishes surveys

Zooplancton (net 1)

Phytoplancton

Physico-chemistry

Transparency (Secchi)

General conditions

Léman

On paper ……………………………………………….

Annecy

On paper………………………………………………………………….

{…..on paper …………….}

Bourget

Historical data

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0

20

40

60

80

100

120

56 59 62 65 68 71 74 77 80 83 86 89 92 95 98

ANNECY

LEMAN

BOURGET

µg/l PO4Increasing pollution Control of wastewater

Long term dynamics of lakes: Eutrophication - Reoligotrophication

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Phosphorus = limiting factor

Bottom -up control Anneville et al., 2007 Journal of¨Plankton Research)

Long term dynamics of lakes: Trophic network changes

Abondance

Abondance

Abondance

Temps

Temps

Temps

PO4

EffetEffet

RéponsRéponsee

RéponsRéponsee

Abondance

Temps

RéponsRéponsee

Abondance

Temps

EffetEffet

Abondance

Temps

RéponsRéponsee

Abondance RéponsRépons

eeA

bondance RéponsRépons

ee

050

100150200250300

Bio

volu

me

(m

l.m-2)

050

100150200250300350

Cat

che

s (t

ons)2.52.72.93.13.33.53.7

74 80 86 92 98 04Log

(B

iov+

1)

(µg.

l-1)

PO

4 (

µg/

L)

020406080

100

74 80 86 92 98 04

Lake Leman Top-Down control

Changes in fish diversity(oligotrophy)

Coregonus albula

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LACS

Thank you for attention

http://www.dijon.inra.fr/thonon