Soil and vegetation parameters monitoring system
Soil heat fluxes, temperature and moisture measurements
The soil heat flux between 5 cm and 80 cm depth are measured with a self-calibrating heat flux sensor (HFP01SC-L, Hukseflux) .
The soil temperature profile (STP01-L, Hukseflux) measures temperature versus depth (temperature gradient) in the soil. It contains 5 thermocouples, tc, (at 2, 5, 10, 20 and 50 cm depth) and one reference Pt100 temperature sensor (at 50 cm).
A Water Content Reflectometer (CS616-L, Campbell) measures the volumetric water content of soils. The measurements were made at 5, 10, 20, 40 and 80 cm depth from the surface. The graph (left) shows the volumetric water contents of soils as they change with time.
Soil chemical, physical and biological parameters measurement
Five experimental sites have been set for soil and vegetation parameters measuring (two grasslands (fenced grassland and grazing grassland) and three croplands). The dominant grass at the site was Stipa. bungeana. Three croplands were mainly cropped with Solanum tuberosum L, Setaria italica Beauv, and Semen Sesami Nigrum in rotation. Soil samples are taken to 100cm at seven depths (0–10, 10–20, 20–30, 30–40, 40–60, 60–80 and 80–100cm) and following parameters are measured:
Chemical parameters:SOC (soil organic carbon) , total nitrogen and pH.
Physical parameters:Soil particle size (Automatic Granularity Laser,MALVERN, Germany), soil bulk density and the dynamics of moisture in soil.(Time-domain reflectometer (TDR) ).
Biological parameters:Soil respiration (LI-COR 64009, LI-COR).