jordtemperaturen

Jordtemperaturen, or soil temperature, is the temperature of soil at a given depth, typically reported in degrees Celsius. It influences biological processes such as microbial activity, root growth, and nutrient availability, as well as physical processes like water movement and soil respiration.

Measurement and data collection commonly rely on probes inserted into the soil connected to thermometers or data loggers. Surface temperature can be measured with infrared sensors or shallow probes. Reference depths frequently used in research and practice include 5 cm, 10 cm, 20 cm, and 50 cm, though deeper measurements are used for frost and permafrost studies.

Temporal patterns of jordtemperaturen vary with depth. The topmost centimeters exhibit strong diurnal and seasonal fluctuations that track air temperature but are damped and delayed. Deeper layers show smaller fluctuations and longer lag times, with seasonal cycles extending to greater depths in colder climates. Snow cover acts as an insulating layer, reducing winter heat loss. Soil moisture and texture also modulate temperature dynamics, with dry soils heating and cooling more quickly but moist soils having higher heat capacity.

Determinants include solar radiation, air temperature, snow and ice cover, soil moisture content, soil texture and organic matter, and ground cover. Variations in land use and vegetation, as well as irrigation practices, can alter local jordtemperaturen.

Applications span agriculture, where soil temperature informs planting and germination timing; horticulture and greenhouses for optimizing root activity; civil engineering for frost depth and freeze–thaw risk assessment; and climate research, where soil temperature is a key variable in land-surface models and climate-change studies.