Exams is an interactive software application for developing aquatic ecosystem models and rapidly assessing the processes, transport and exposure concentrations of synthetic organic chemicals, including pesticides, industrial materials and waste disposal sites. Exams contains an integrated database management system (DBMS), which is specially used to store and manage the project database required by the software. User interaction is provided by a fully functional command line interface (CLI), the use of flexible help menus, an online data dictionary, and a cli user guide, and maps the ability to check output data.

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.

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.

The development of the lean model and its application in several parts of the continental United States were managed by a team of faculty, staff and students at the University of Illinois at Urbana Champaign. Leam helps others understand the relationship between human economic / cultural activities and biophysical cycles from the perspective of changing land use. Understanding how one system affects another will enable us to make better land use management decisions in the future.

HSPF (hydraulic simulation program - FORTRAN) model is a mathematical model developed by the U.S. Environmental Protection Agency (EPA). It is used for continuous simulation of hydrological and water quality processes in a large watershed under natural and artificial conditions. The model is written in FORTRAN language and based on Stanford hydrological model. It can comprehensively simulate runoff, soil loss, pollutant transport, river hydraulic and other processes, and is widely used in the scenario simulation of watershed water environment effects of climate change and land use change. The model is an excellent representative of semi distributed hydrological and water quality model, HSPF model is widely used in foreign countries. HSPF model includes perlnd, implnd and rchres to simulate the hydrology and water quality of permeable section, impervious section and surface water body respectively. Generally speaking, HSPF model plays an important role in the simulation of hydrology and water quality process in foreign countries, as well as scenario analysis involving climate change and land use impact, But the application of this model in China is very limited

The common land surface model was developed by scientists interested in land model for public use and further development. The main characteristics of the model include sufficient non-uniform interlayer to fully represent soil temperature and soil moisture, and multi-layer parameterization of snow process; clear treatment of liquid water and ice water quality in snow soil system; runoff parameterization under the concept of topmeod; a canopy photosynthetic conductivity model, which describes the simultaneous transfer of carbon dioxide and water vapor in plants; and a model of canopy photosynthesis conductivity; The sub grid fraction of energy and water balance is tiled. CLM has been widely evaluated in offline mode and coupled with the NCAR community climate model (CCM3).

Algorithm model of continuous multi flow confluence