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RECIPE meeting, Charquemont October 23, 2003. Andy Siegenthaler Swiss Federal Research Institute WSL Antenne romande CH-1015 Lausanne / Switzerland. Close collaboration with Estelle, sharing sites an methane measurements. La Chaux d’Abel / Le Russey. Le Russey. La Chaux d’Abel.
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RECIPE meeting, CharquemontOctober 23, 2003 Andy Siegenthaler Swiss Federal Research Institute WSL Antenne romande CH-1015 Lausanne / Switzerland
Close collaboration with Estelle, sharing sites an methane measurements
La Chaux d’Abel / Le Russey Le Russey La Chaux d’Abel
Bog regeneration typology of the Jura - Thesis from Yvan Matthey, 1993 • Yvan Matthey’s work concerned the description of 369 situations along the Jura chain. He used factorial analyses using 6 common environmental descriptors. • He describes three progressive series which differentiate into two independent (aquatic and terrestrial), and two parallel terrestrial progressive (changing) series. The ultimate stages of the 3 series’ evolutions show an obvious physiognomic “uniformisation” of the environments. • Terrestrial: • Hummocks’ serie (Eriophorum vagintum) • Moss-lawns’ serie (Polytrichum strictum and Polytrichum commune) Aquatic: • Trembling marsh (Potentilla palustris …Phagnum magellanicum) • He also points out the importance of the mosaïc aspect in the early stages. At la Chaux d’Abel, we have a mixture of the two terrestrial situations that appear in mosaïc plus a gradient in the progressive stages.
Choice of keystone species (WPI & WPII) Baubt: Eriophorum angustifolium, Eriophorum vaginatum ? Triglochin sp?, Molinia caerulea? Finland: Sphagnum sp, Eriophorum vaginatum, …? Question: common plant species in order to compare climatic gradient (at least Sphagnum sp + 1 specie)? Chaux d’Abel / Russey: Sphagnum sp, Eriophorum vaginatum, E. angustifolium and Polytrichum strictum Scottland: Sphagnum sp, Eriophorum vaginatum, …?
8 8 7 7 8 7 8 7 8 7 7 7 7 7 7 8 7 2 2 1 1 5 5 5 5 5 5 5 5 5 5 3 3 3 3 3 3 3 3 3 3 3 6 6 6 6 6 6 6 6 6 6 6 4 4 4 4 4 4 4 4 4 4 4 I. Semi-systematic II. Systematic Taken for the analyses (i.g.) I II Sub-sampling strategy I and II in various situations Vascular plants’ litter Mosses or peat: 0<h≤5 cm below surface Peat: 22.5-27.5 cm below the surface Peat: 32.5-37.5 cm below the surface Vascular plants’ stems and leaves Mosses or peat: 5-10 cm below surface Peat: 12.5-17.5 cm below the surface Peat: 42.5-47.5 cm below the surface some analyses 2 New peat 1 some analyses 0 = c = 10 Median water table 20 30 40 = c 50 Old peat 60 Nb of samples: 4(6) 4(6) 5(7) 5(7) 5(7) 4(6) 4(6) 4(6) 3(5) 4(6)
This part has to be filled up with porous peat in order to allow for a horizontally mowing ground water level The trenches at le Russey Buffer zone of 3.50 cm between trenches Low water level: upper part of the pot 30 cm above the highest H Intermediate water level High water level: upper part of the pot 10 cm above the median H Level zero Free water 50 cm Filing up 50 cm 85cm cm Scale 200% Peat in place 11 m If necessary, put a lateral drain to evacuate the water if the trenches fills up H(water level) = min. = -33 cm H = mediane Scale 100% H = max. = old surface peat
Water level I Sp 1 Sp 1 Sp 0 Sp 2 Sp 3 Sp 0 Sp 2 Sp 3 Sp 1 Sp 2 Sp 3 Water level II Slope 5 cm 5 cm Water level III 10 cm 10 cm 10 cm 15 cm 15 cm 15 cm 15 cm 30 cm 30 cm 30 cm 30 cm Assignment of tubes 1 out of 3 trenches (= replicates) Year 1 Year 2 WP 2: Species We would decide to continue for another year looking at some plant-pots. Enough space for handling the corer by two persons 3 m 1.2 m Spare species; litter should not be a problem over two years L 0 L 2 L 1 L 3 WP3: Litter chamber tube Total = 15 pots x 3 water levels x 3 replicates = 135 pots, from which only 72 will be analysed!
Depth /cm Mean temperature profiles - October ‘03
Mean temperatures (ANOVA and Fisher’s PLSD) - October ‘03 a b a/c
a b a/c a a/b c Comparisons of the 3 situations in October ‘03 (ANOVA and Fisher’s PLSD)
Evolution of the pH with depth and sites’ comparison - Sept.’03
Parallel evolution of CO2 and CH4 CA-5(zone C) CA-2(zone A)
Peat sampling - use of a cartridge • PET sheet of 50 cm long, hold in place with a stop-piston, capped at the bottom • minimise the duration of time at which the anoxic peat can be oxidised • less manipulations on the field • makes the transportation easier • enables to store the samples for some time until they can be processed • Preparing the cartridges doesn’t take long
Anoxic slicing of cores • Soft gas-chamber that allows to sample in a O2-free environment • The advantage is that the bag’s air can be emptied before filling with N2-gas - it takes less gas to purge • Easy to make, can be done by all the dispatchers and could even be used in the field • There should be a small N2-flux and we could use PEWA strips to control if there is no oxygen left. • Question: 1) Where do we cut the corer? 2) Do we need to separate the oxic part before introducing the core into the chamber? Who needs preserved samples?
Wooden-peepers for gas, cations and anions measurements • These wooden logs would replace Philipp Steinman’s Plexiglas model • The wooden-peepers would be inserted where we extract the cores - this would ensure a 1 to 1 wedging • There would be plastic pots (diam. 50 mm) with a polysulfon membrane (0.2 µm) on two or four sides (depending on the needs) • The pots can be placed at different depths (0-5, 5-10,…cm), at convenience • More solution can be retrieved (about 100 ml for one pot) than in the Plexiglas model • Should be easier to handle • Question: who does the analyses (PhS, AJF, AS)? (see Philipp’s table)
The fluorescence transient from Strasser et al. 2000