Silwood Park pond mesocosm
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.
We are studying the impacts of warming and extreme temperature events using an array of 96 pond mesocosms. On September 2018 we started a long-term warming experiment with treatments that match climate projections, including constant warming from 1 to 8oC above ambient temperature and events of periodic extreme warming that mimic heat waves. In 2019 chemical stressors will be also applied to a set of ponds. The Silwood Park pond mesocosms are part of the Ring of Fire project that integrates information generated from a global collection of naturally warmed freshwater habitats across a circumpolar ring of geothermal activity, hundreds of large-scale artificial streams and ponds (mesocosms) in the field, and thousands of robotically-assembled microbial communities in the laboratory (microcosms).
With a set of 32 pond mesocosms we aim to help understanding the effects or drought in freshwater systems. This experiment replicates the design used in a network of six mesocosm facilities located along a thermal gradient in the Iberian Peninsula (freshwater systems).
The Ring of Fire project is one of the experiments of The Grand Challenges in Ecosystems and the Environment Initiative (GCEE) and the Aquacosm, an international network of experimental infractrusctures that facilitates transnational research in marine and freshwater ecology. This experiment by funded is NERC grants awarded to Professor Guy Woodward, Dr. Thomas Bell, Dr. Samraat Pawar, Dr. Alex J. Dumbrell, Professor Mark Trimmer and colleagues from Imperial College London, 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 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
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
Teamwork in a sunny day!
Teamwork in a sunny day!
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
Understanding complex ecosystems
Dr. Samraat Pawar talk about his research aiming to predict the effects of environmental change on ecosystems
Mesocosm google map
details pond mesocosm
Experimental design
The 96 pond mesocosms are artificial tanks about 2m diameter and 1 m deep. They were set above ground in Autumn 2015 and then filled with a thin layer of sand and gravel and with tap water to the top. Tanks are set in 8 columns (A to H) and 12 rows (1 to 12) about 4m appart from each other.
During March 2016, all ponds were seeded with a similar pool of freshwater organisms. Seeding consisted on adding to each pond a combination of water and sediment from creeks in Silwood Park and neighbouring regions. Tap water was used to fill the rest of each pond.
On 5th of September 2018 warming treatments started. 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.
The 32 pond mesocosms are a set of artificial 1000L above ground tanks that in Summer 2017 were filled with a thin layer of sand and gravel and then with tap water to the top.
Data
Core data includes:
- Metagenomic and metatranscriptome data from ponds to characterize the microbial community composition and gene expression with focus on genes related with C and N cycling.
- Rates of breakdown of leaf-litter and cellulose.
- Ecosystem respiration and primary production
- N2 fixation, N2 and N2O production, plus production and oxidation of methane
- Invertebrate sampling
Find here the metadata file for this experiment (71KB)