A mesocosm experiment testing the combined effects on plankton community of a terrestrial organic matter runoff and a warming in small freshwater reservoirs

Small freshwater reservoirs are ecosystems of global importance both for the great biodiversity they shelter, the ecosystem services they provide and the freshwater resources they constitute. An increase in temperatures and precipitation intensity due to climate change is expected by the end of the century. These changes should result in an increase in interactions between lakes and watersheds, leading in particular to increased inputs of terrestrial organic matter (tDOM) likely to impact the functioning of small lake ecosystems.
In this context, a mesocosm experiment was carried out to study the combined effect of two disturbances - input of tDOM and temperature rise - on pelagic communities. The experiments were conducted within the National Experimental Platform for Aquatic Ecology (PLANAQUA) at CEREEP-Ecotron Ile-de-France located in Saint-Pierre-lès-Nemours (France). The experiment was carried out in twelve 1m3 mesocosms placed outside during 6 weeks, from June 8 to July 19, 2021. ..., Mesocosms
The mesocosms (called ECORIUM) are made of double-walled 316 stainless steel tanks. The internal diameter is 1300 mm and the height is 820 mm. Glycol water circulates within the double wall to regulate the temperature inside the tank between -10°C and 45°C.
The three in situ control mesocosms were labeled C1, C2, C3, the three mesocosms in which terrestrial runoff was simulated were labeled T1, T2, T3, the three mesocosms in which temperature warming was simulated were labeled W1, W2, W3, the three mesocosms in which both terrestrial runoff and temperature warming were simulated were labeled TW1, TW2, TW3.
Sampling and in situ measurements

Sampling was done using a 2-L sampling bottle (Uwitec Sapling Bailer USB 50020, Mondsee, Austria).
Immersion of a multiparameter probe (YSI EXO2) was performed after stirring to measure the temperature, conductivity, turbidity, salinity, pH, O2 saturation and Chlorophyll a values in surface waters.
Immersion of a multispectral spectrofluoro..., # A mesocosm experiment testing the combined effects on plankton community of a terrestrial organic matter runoff and a warming in small freshwater reservoirs

Dataset DOI: [10.5061/dryad.v15dv428q](10.5061/dryad.v15dv428q)

## Access information

Comments and requests should be addressed to D. Lamy, F.D. Hulot, S. Fiorini and F. Joux.

**Acnowledgements**

These datasets were produced thanks to the help of Francis Dohou from CEREEP, Gwendal Latouche, Clotilde Perrot-Guillaume, Marion Francisque, Élise Cabanne, Geoffrey Devisse, from ESE. This work was part of the RESTORE project, funded by the French National Research Agency under the grant n°ANR-19-CE32-0013.

## Description of the data and file structure

**Temporal extent**: 2021-06-8 – 2021-07-19

**Location**

48.283305N, 2.671189E

### Files and variables

The dataset resulting from this experiment are included in the archive \"Data_WP2_RESTORE_mesocosm_experiment.zip\".

Please note that the variables definitions are included as e...,