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, Date/month/year Moisture characteristics

, Less than 10 mm PPT fell within the previous three weeks. 16-18/12/2001 Partially moist BSC surfaces from water drops, which condensed on dry but standing grass blades and dropped wetting surrounding surfaces

, Rates of BSC photosynthesis indicating at least temporary water supra-saturation. 13-15/01/2002 Water condensation on soil surfaces during nights. Intensity of surface moisture and VWC of the upper soil column pointing to a recycling of water from recent infiltration, Recurring PPT alternating between rainstorm and drizzle, p.15

, Fog in the morning of 20/01, subsequent rain and frequent changes of cloudy and sunny conditions with maximum photosynthesis

, Low moisture supply from raindrops (<0.5 mm, 23/11 15:30) and shower (<1 mm around midnight 24-25/11)

, /12) and reduction of BSC activity due to cloudy weather and wind drying the following day. 19-21/01/2003 Repeated rain showers alternating with cloud-free light conditions resulting in maximum photosynthesis rates

, BSC area index for calculations was 0.6. Modifications in the model reflect water supply from (a) rain "r", (b) rain and increased soil moisture "r+sm", and (c) rain, soil moisture, and high relative air humidity "r+sm+rh". Years were cal, Table 4. Inter-annual variability in BSC-related net carbon deposition as assessed by the precipitation-driven activity model (PdAM)

, Yr period PPT (mm) BSC-related carbon deposition, C (kg ha ?1 yr ?1 ) (a) "r" (b) "r+sm

, * as assessed from measured mean values, see paragraph 3.1

, * * note that no field experiments were conducted before the season, 2001.