One variation of a method includes, during a test period: triggering release of a tracer test load into air in an environment, according to a set of release parameters, by a dispenser arranged within the environment, the first tracer test load comprising a first concentration of tracers of a first type in solution; and triggering an air sampler, located in the environment, to record a timeseries of aerosol data representing amounts of aerosol particles detected at the air sampler during the test period. The method further includes: deriving a tracer signal, representing changes in amounts of tracers in air detected at the air sampler during the test period, based on the timeseries of aerosol data and the set of release parameters; based on characteristics of the tracer signal, characterizing a set of aerosol flow metrics representing behavior of aerosols in the environment during the test period.

An automatic sampling device and method for determining greenhouse gas emission flux from farmland are provided. The device includes a static chamber, a flow meter, and a collection box. The static chamber communicates with a gas inlet of the collection box. The flow meter is arranged in a gas pipe between the static chamber and the collection box. The static chamber is used to cover plants to be tested and to keep the plants to be tested in a closed environment. The flow meter is used to determine a gas flow rate in the gas pipe between the static chamber and the collection box in real time. The collection box is internally provided a plurality of collection loops and a controller. Each collection loop is used to collect a gas in the static chamber at different time according to collection settings of the controller.