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 apart from each other (see figure below).
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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.
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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.
Core Data
Core data includes:​
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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.
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Rates of breakdown of leaf-litter and cellulose.
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Ecosystem respiration and primary production
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N2 fixation, N2 and N2O production, plus production and oxidation of methane
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Invertebrate sampling
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Find here the metadata file for this experiment (71KB)