EVENT 2
Links to publications and pictures of EVENT 2
Experimental Design
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| EVENT 2: Erwärmung |
The experiment is carried out in a two-factorial design manipulating
(1) weather events (early drought, late drought, weekly average precipitation, control), and
(2) mowing regime (2 and 4times/ year).
The design consists of 150 plots, each 1.5 m by 1.5 m in size, with every factorial combination replicated five times. Manipulations are applied in a modified Latin Square design; mowing regimes are blocked and randomly assigned within each manipulation.
Factor 1: weather manipulation / extreme weather events
Available are 5 weather manipulation blocks:
1. minimal variability (CM): compare weekly precipitation sums with long-term average for the same period and irrigate if smaller (CM as carried out last year). Applied between 1.4. and 30.9.
2. ambient (unknown) variability (CA): ambient precipitation regime with updates to CM by irrigating the missing amount at five dates (before D1 starts, before D2 starts, end of D2, mid August, end of September)
3. more extreme 1 (D1): same as Ca with drougth period in spring (amount missed due to drought manipulation will be addes after the drougth treatment)
4. more extreme 2 (D"): same as CA with drought period in summer (amount missed dur to drought manipulation will be added after the drought treatment)
5. roof artefact controll (XX): same amount and timing as CA, but irrigated below roofs with roofs installled during spring drought (daily irrigation if necessary)
All 5 manipulations will add up to the same total sum of precipitation, but differ in the variability. Intensity of drougth is based on the local 1000-year extreme event resulting in a drought period of 42 days. Drougth ist sumulated usind rain.-out shelters.
Factor 2: mowing regime
N1: 2x mowed/year
N2: 2x mowed/year + X
N3: 4x mowed/year
N4: 4x mowed/year + X
N5: 2x mowed/year
N6: 2x mowed/year
X: Plots weill be manipulated additionally to mowing, not yet decided how
N5/N6: reserced for future experiments
Response Parameters
Performance of communities and single species is measured with a variety of parameters, covering all important stages in the life cicle of plants (cover, above and belowground biomass porduction, phenology, seed production, germinabilityor photosynthetic actovity).
Factor (1): weather manipulation/ extreme weather events:
Available are 5 weather manipulation blocks: minimal variability (CM): compare weekly precipitation sums with long-term average for the same period and irrigate if smaller (CM as carried out last year). Applied between 01.04. and 30.09. ambient (unknown) variability (CA): ambient precipitation regime with updates to CM by irrigating the missing amount at five dates (before D1 starts, before D2 starts, end of D2, mid August, end of September) more extreme 1 (D1): same as CA with drought period in spring (amount missed due to drought manipulation will be added after the drought treatment) more extreme. (D2): same as CA with drought period in summer (amount missed due to drought manipulation will be added after the drought treatment) roof artefact control
Factor (2):
Factor (3)
Factor (4)
Factor (5)
Response Parameters
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| EVENT 2:sorting Biomass |
Performance of communities and single species is measured with a variety of parameters, covering all important stages in the life cycle of plants (cover, above and belowground biomass production, phenology, seed production, germinability or photosynthetic activity). Furthermore, abiotic parameters like soil moisture, precipitation and temperature are recorded on site. Through cooperation partners, other important ecosystem parameters are analyzed, e.g. microbial activity, soil fauna, N-cycle, stable isotopes.
Publications EVENT 2