Author
Ahuja, Lajpat | |
Green, Timothy | |
Erskine, Robert - Rob | |
Ma, Liwang | |
Ascough Ii, James | |
Dunn, Gale | |
Shaffer, Marvin | |
MARTINEZ, ANA - COLORADO STATE UNIV |
Submitted to: CRC Book: Agricultural Sys Models in Field Research and Technology Transfer
Publication Type: Book / Chapter Publication Acceptance Date: 11/20/2001 Publication Date: 4/29/2002 Citation: Ahuja, L.R., Green, T.R., Erskine, R.H., Ma, L., Ascough Ii, J.C., Dunn, G.H., Shaffer, M.J., Martinez, A. 2002. Topographic analysis, scaling and models to evaluate spatial/temporal variability of landscape processes and management. CRC Book: Agricultural Sys Models in Field Research and Technology Transfer. April 2002. Chapter 13, pp 265-272. Interpretive Summary: Topography is an important factor to consider in land management systems. Through its effects on long-term soil formation and short-term seasonal effects, the topography greatly influences the spatial variability of soil properties, soil processes, and their interaction with variable weather conditions. With the availability of high precision global positioning systems, a landscape's topography can be determined to within a few centimeters. We explore the hypothesis that accurate topographic analysis, available soil map data, and process-level agricultural ecosystem models can be combined to improve spatial characterization of soils and soil processes on a landscape, and this characterization can then be used to evaluate and guide spatial and temporal land management. We review the literature on the relationship of certain topographic attributes (elevation, slope, aspect, contributing or catchment area, and their combinations) with the variability of soil properties (e.g., texture, depth, organic matter content), soil processes (soil water and related variables), and crop growth. Contributing area, slope, and curvature may be used to delineate sub-units of land for differential management, and then appropriate models can be used to evaluate their responses to alternate management practices or land uses under varying weather conditions during a season and from year to year. Technical Abstract: Topography is an important factor to consider in land management systems. Through its effects on long-term soil formation and short-term seasonal effects, the topography greatly influences the spatial variability of soil properties, soil processes, and their interaction with variable weather conditions. With the availability of high precision global positioning systems, a landscape's topography can be determined to within a few centimeters. We explore the hypothesis that accurate topographic analysis, available soil map data, and process-level agricultural ecosystem models can be combined to improve spatial characterization of soils and soil processes on a landscape, and this characterization can then be used to evaluate and guide spatial and temporal land management. We review the literature on the relationship of certain topographic attributes (elevation, slope, aspect, contributing or catchment area, and their combinations) with the variability of soil properties (e.g., texture, depth, organic matter content), soil processes (soil water and related variables), and crop growth. Contributing area, slope, and curvature may be used to delineate sub-units of land for differential management, and then appropriate models can be used to evaluate their responses to alternate management practices or land uses under varying weather conditions during a season and from year to year. |