Learn more about the Agricultural Policy Environmental eXtender model
APEX, a comprehensive process-based agroecosystem model developed and maintained by the Blackland Research Center (BREC) at Texas A&M AgriLife Research, is similar to EPIC. It simulates the interactions between climate, soil, water, nutrients, and agricultural management practices to assess their impacts on crop yields, soil erosion, water quality, and greenhouse gas emissions. APEX extends EPIC’s capabilities by simulating land management impacts for small-medium watersheds and heterogeneous farms through its unique capability to simulate hydraulic connections between different parts of the simulated area.
Key Features
Water routing
APEX simulates the movement of water through channels or flood plains, along with sediment, nutrients, and pesticides dissolved in the water or attached to the sediment.
Crop growth
APEX simulates the growth of a wide range of plants, considering factors such as temperature, precipitation, sunlight, soil characteristics, nutrients availability, and land management. It can also model multiple plants growing simultaneously in the same field, including competition for light, water, and nutrients.
Soil erosion
APEX predicts water- and wind-driven soil erosion, helping in the evaluation of agricultural and conservation practices for preventing or reducing soil loss in farms and small watersheds.
Water quality assessment
APEX simulates the movement of nutrients and pesticides through the soil and into water bodies, assessing agricultural impacts on water quality. Its water routing component enables the simulation of water-transported sediment, nutrients, and pesticides within farms or watersheds.
Carbon cycling
Using the same approach adopted in the EPIC model, APEX can simulate carbon dynamics in the soil-plant system. It models the transfer between pools of soil organic carbon and the mineralization of plant residues based on climatic conditions, soil characteristics, and land management.
Nutrients cycling
The model tracks the dynamics of nitrogen and phosphorus, simulating several processes such as fertilization, plant uptake, mineralization, losses with runoff and leaching, and for nitrogen losses by denitrification and volatilization.
APEX can perform long-term continuous simulations to model the impacts of various nutrient management practices, tillage operations, conservation practices, alternative cropping systems, and other management practices on surface runoff and losses of sediment, nutrients, and other pollutant indicators, crop yield, and conservation of natural resources.
More information about the APEX model are available here.
Ask us about the APEX model
Do not hesitate to contact us if you need more information on the APEX model and how it can help in your research.