The full impact of rapid environmental changes on natural ecosystems remain poorly understood as complex interactions between biological systems add emergent properties that can only be understood using an interdisciplinary and holistic approach. Artificial ponds (mesocosms) at Silwood Park are helping to assess the impacts of warming, drought and chemical pollution in freshwater systems by studying multiple levels of biological organisation, from genes to food webs and whole ecosystems.

The mesocosm facility is part of the Georgina Mace Centre for the Living Planet. Experiments run in the facility have been funded by NERC grants awarded to several academics from Imperial College London including Professor Guy Woodward, Professor Thomas Bell, Dr. Samraat Pawar,  Dr. James Rosindale and Dr. Emma Ransome and to colleagues from University of Essex, Queen Mary, University of London, and other institutions in the UK.

Mesocosms video playlist

GCEE Research Focus - Dr. Guy Woodward

Professor Guy Woodward talk about the goals for Silwood mesocosm project and his research exploring the effects of environmental stress on multi-species ecosystems 

Listen to Dr. Woodward talking about the mesocosms

GCEE Research Focus - Dr. Guy Woodward

Professor Guy Woodward talk about the mesocosms and his research program

Professor Guy Woodward talk about the goals for Silwood mesocosm project and his research exploring the effects of environmental stress on multi-species ecosystems 

Birdview of the ponds in October 2016

Silwood pond mesocosm

Birdview of the ponds in October 2016

Birdview of the mesocosm in October 2016 before Masters students sampled the ponds

The making of Silwood mesocosm

The making of Silwood mesocosm

Teamwork in a sunny day!

Teamwork in a sunny day!

Experimenting with pond bacteria in the lab

GCEE Research Focus - Dr. Thomas Bell

Experimenting with pond bacteria in the lab

Dr. Bell explain the importance of bacteria in ecosystems and his research describing natural communities and experimeting with them in the lab to understand how community assembly is affected by environmental stress.  Some of these microcosm experiments will address the effect of temperature in communities of bacteria collected in Silwood pond mesocosms.

GCEE RESEARCH FOCUS: DR. SAMRAAT PAWAR

GCEE RESEARCH FOCUS: DR. SAMRAAT PAWAR

Understanding complex ecosystems

Dr. Samraat Pawar talk about his research aiming to predict the effects of environmental change on ecosystems

Mesocosm google map

details mesocosm

Publications

Jackson MC, Pawar S, Woodward G (2021) The temporal dynamics of multiple stressor effects: from individuals to ecosystems Trends in Ecology and Evolution, 36: 402-410

Morris OF, Loewen CJG, Woodward G, Schäfer RB, Piggott JJ, Vinebrooke RD, Jackson MC (2022) Local stressors mask the effects of warming in freshwater ecosystemsEcology Letters, 25: 2540-255

Facility

The facility counts with six pond mesocosms (271 ponds), a water purification system and tanks with the capacity of storing up to 18,700 litres of rain or distilled water.

Pond mesocosms are artificial tanks with capacity of about 1 or 1.8 cubic metres set above ground. They were stablished with a thin layer of sand and gravel, filled to the top and with tap or rain water and seeded with freshwater organisms. Seeding consisted on adding to each pond a combination of water and sediment collected from streams in Silwood Park and neighbouring areas. 

Warming treatments in one set of ponds started on 5th of September 2018. Ponds are warmed from 1 to 8 oC above ambient water temperature: 36 ponds with ambient temperature, 4 ponds at +1oC, 14 at +2oC, 4 at +3oC, 22 at +4oC, 4 at +5oC, 4 at +6oC, 4 at +7oC and 4 at +8oC. The mesocosm control system was designed and implemented by Martin Rouen from Lakeland Instrumentation Ltd.

Find out more about the Mesocosms facility summary and its experiments.

seeding March 2016

Seeding of tanks with help of master's students, March 2016 (courtesy of Bruno Gallo)

G8 tank

Artificial ponds

heating elements

Pond with heating element (From September 2018)

february 2018

February 2018

heating

Autumn 2018

mesocosms pond

Algal growth in mesocosms ponds by November 2016