The full text of this item is not available at this time because the student has placed this item under an embargo for a period of time. The Libraries are not authorized to provide a copy of this work during the embargo period, even for Texas A&M users with NetID.
Cover- and Double-Cropping Impacts on Soil Health and Moisture of a Dryland Winter Wheat System in the Texas Rolling Plains
MetadataShow full item record
Constraints on food, land and water resources pose a need for conservation practices to maintain viable agricultural lands. Wheat - a staple cereal grain for humans and animals worldwide - has been heavily cultivated in the Great Plains of the United States well before the 1900s. Historically in this region, tillage and fallow periods were implemented as a means to conserve soil moisture during summer months. However, almost 100 years ago, these practices in conjunction with long periods of drought followed by large wind events resulted in the Dust Bowl of the 1930s and brought immense erosion and loss of topsoil to the southern Great Plains. Advances in conservation management to provide crop cover to soil surfaces and reduction in tillage have helped protect the soil in the Great Plains; however, adoption of these practices remains low in part due to concerns for soil moisture preservation. Although the potential for no-tillage and cover crops to protect the soil, build organic matter, and improve soil health has been demonstrated across much of the USA, little research has focused on the application of these techniques to the Texas Rolling Plains region. The objective of this study was to evaluate cover and double cropping practices in a wheat monocropping system under no-till management and their effects on soil health and soil moisture. A wheat-fallow control was compared to seven treatments with various cover crops in rotation including legumes and mixtures treated as cover crops or double crops. Soils were collected and analyzed for biological, chemical and physical properties including microbial biomass, mineralizable carbon, soil carbon and nitrogen fractions, soil aggregate distribution and water content. After three years of cover crops in rotation, there was generally greater soil microbial biomass and activity with treatments receiving cover. In addition, by implementing cover and double crops, soil moisture was not negatively impacted during the study period and those treatments had greater volumetric water content following precipitation events compared to the wheat-fallow control. Some parameters of soil health did not respond to the intensified wheat system; however, many soil characteristics (such as soil organic carbon) change on decadal time scales, and longer-term studies may be needed to more fully evaluate their potential responses. Results indicate cover and double crops can be a viable method to build soil health and sustainability without reducing soil moisture in wheat-monocropping systems in the Texas Rolling Plains.
Schirmacher, Marie Theresa (2019). Cover- and Double-Cropping Impacts on Soil Health and Moisture of a Dryland Winter Wheat System in the Texas Rolling Plains. Master's thesis, Texas A&M University. Available electronically from