At present, the plastic tarpaulin used in soil fumigation process has been proved to be able to penetrate into the fumigation steam and cause obvious loss to the atmosphere. New low permeability membranes are being developed to reduce fumigant emissions and improve efficacy. A fast, reliable and sensitive method is needed to measure the permeability of various membranes that may be used in new management practices. Filmpc provides a method for estimating the mass transfer coefficient (H) of fumigants in agricultural films. H is a measure of diffusion resistance. Unlike other permeability measurement methods, h is an attribute of film chemical combination, independent of the concentration gradient of the whole film. The model relies on a mass balance method, and adsorption and diffusion are carried out on the membrane. The results show that this method produces a sensitive and reproducible method for measuring membrane permeability.

Parflow is an open source, object-oriented and parallel watershed scale model. It includes a fully integrated land flow with the ability to simulate complex topography, geology and heterogeneity, as well as land surface processes including land energy budget, biogeochemistry, and snow (through CLM). It can run on multiple platforms. Parflow is the result of a long, multi agency development history and is now a collaboration between CSM, LLNL, uni Bonn and UCB. Parflow is combined with mesoscale, weather code ARPS and NCAR code WRF.

Gawser is a temperature index snow melting model which can be used to verify the hydrology of the basin. It is most suitable for agricultural or forest watersheds, but can be used to demonstrate the hydrology of other types of watersheds, such as urban or suburban water sheds. Gawser is suitable for basins with different development levels and can be used to show the impact of development on watershed hydrology. For example, in order to observe the hydrological impact of deforestation on agriculture, data can be used to simulate hydrological conditions in forest basins, and then reprogrammed to simulate hydrology in agricultural watersheds. We can study the behavior of runoff, infiltration, base flow and other hydrological conditions in each watershed.