The inherent spatial heterogeneity of soils means that a soil CO₂ flux reading taken at one location can be significantly different from a reading taken even meters away. The Survey configuration provides a way to rapidly take measurements in multiple locations in order to calculate a spatial average. The system is quickly and conveniently moved from collar to collar to "survey" flux rates over a larger area of interest.

A Survey System is easily carried by the user. The Analyzer Control Unit comes with a shoulder strap, and each chamber is lightweight and comes with a handle. A soil temperature sensor is included with Survey chambers, and a soil moisture sensor is optional - readings from these auxiliary sensors are integrated into the dataset. Power is provided by an onboard, rechargeable battery. The user can easily configure and monitor the system on a PDA while out in the field using the Wireless Communications Package (recommended). Data can be stored either on internal flash memory or a Compact Flash card (included).

Integrating GPS Coordinates with Soil Flux Data

The 8100-405 CO₂ Mapping Kit is designed to interface with the LI-8100A Soil CO₂ Flux System, to allow spatial data (latitude, longitude) to be integrated with observations of soil CO₂ flux. The CO₂ Mapping kit can be used with either of the instrument's survey chambers (8100-102 and 8100-103) to map soil CO₂ fluxes across a given area (Figure 1).

Figure 1: Soil CO₂ fluxes measured in a forest edge/mowed field transition.
Fluxes (µmol m-2 s-1) were measured on August 18, 2011 in the late afternoon, and are plotted in false color. Isotherms for soil temperature (C) measured at 5 cm depth are included. Soil temperature correlates positively with soil CO₂ flux over much of the study area, with the exception of the region where the highest temperatures were observed. In this small area vegetation is sparse and the soil is predominantly exposed.