Location: Watershed Management Research
Project Number: 2052-13610-012-02-I
Project Type: Interagency Reimbursable Agreement
Start Date: Sep 22, 2015
End Date: Sep 30, 2018
BLM is requesting assistance from the USDA Agricultural Research Services to support an effort to update the SEM Model making it more user friendly. This Intra-Governmental Order (IGO) describes work that will be conducted to meet this objective and provides funding to reimburse ARS for costs incurred during the three-year project.
The vegetative productivity of western rangelands is strongly dependent on the amount of plant available water stored in soil, especially where winter precipitation is substantial. This productivity is critical for rangeland management because it is a primary constraint on the amount of grazing the land supports without degradation. Productivity not only varies from site to site, but also within and between years at a given site. Thus, productivity estimation is complex, depending on site characteristics as well as weather variations within a site. The Soil Ecohydrology Model (SEM) uses a water balance approach that integrates site characteristics and weather to estimate rangeland vegetative productivity and water loss to groundwater or streamflow on upland soils. It has been proven to effectively simulate plant water use in sagebrush environments (Seyfried et al., 2009; Finzel et al., 2015). The model can potentially provide information to managers regarding the relative productivity of different locations and/or provide estimates of future production either within a season or given differing climatic scenarios. Although SEM is a relatively simple model, it has been used in a research context and is not “user friendly”. At present the user must determine appropriate soil and vegetation parameters and then find and enter the required weather data in the correct format. This all requires knowledge of ecology, hydrology and the program. In addition, the current program is designed to run simulations at one specific site at a time, requiring the user to enter data for each site, one at a time. This is fine if there are a limited number of sites of interest, but problematic if numerous sites are of interest. This project will enhance the SEM model by developing a user interface that facilitates user input of the required parameters, provides guidance for determining those parameters and is capable of running multiple sites in a single “batch”.