Author
ALSHEIKH, A - CSU | |
Delgado, Jorge | |
BARBARICK, K - CSU | |
SPARKS, R - USDA-NRCS | |
DILLON, M - CSU | |
QIAN, Y - CSU | |
CARDON, G - CSU |
Submitted to: Soil Tillage Research Organization International Conference Proceedings
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 3/27/2005 Publication Date: 11/2/2005 Citation: Alsheikh, A., Delgado, J.A., Barbarick, K., Sparks, R., Dillon, M., Qian, Y., Cardon, G. 2005. Effects of Potato-Grain Rotations on Soil Erosion, Carbon Dynamics and Properties of Rangeland Sandy Soils. J. Soil Tillage Research. 81:227-238. Interpretive Summary: We conducted an assessment of the effects of cropping systems in soil physical and chemical properties of coarse sandy soils. We studied the impact of incorporation of small grain in a potato (Solanum tuberosum L)-grain rotation by sampling an uncultivated rangeland site and three fields that two decades ago were converted from rangeland into cultivated center pivot irrigation sprinkler fields. Plant and soil samples were collected in the rangeland area and the three adjacent cultivated sites. We found that for the rangeland site the brush species is contributing to C sequestration and increases in soil organic matter (SOM) while the bare soil areas of the rangeland are losing significant amounts of fine particles, nutrients and SOM. When we compared the cultivated sites to the uncultivated rangeland, we found that the SOM, soil organic carbon (SOC) and soil organic nitrogen (SON) increased with increases in crop residue returned into the soils. Erosion or losses of fine silt and clay particles were reduced with the inclusion of small grains. Cropping tools, such as crop rotations are universal tools that have the potential to protect soil quality and fertility and thereby contribute to agricultural sustainability. Technical Abstract: We conducted an assessment of the effects of cropping systems in soil physical and chemical properties of coarse sandy soils. We studied the impact of incorporation of small grain in a potato (Solanum tuberosum L)-grain rotation by sampling an uncultivated rangeland site and three fields that two decades ago were converted from rangeland into cultivated center pivot irrigation sprinkler fields. Cultivation and irrigation lowered soil pH by about one unit. The amount of silt and clay was significantly reduced in the cultivated sites. The lower percent of fine particles in the cultivated sites could be due to wind erosion. The content of macro and micro nutrients such as P, Zn, Fe, Mn, and Cu were higher in the cultivated sites than the rangeland. The only nutrient that a loss was measured for was K with about 66% decrease due to K uptake, wind erosion, and K leaching. We also found that for these sandy soils some of the N fertilizer is being sequestered in the soil organic matter. The particulate organic matter-nitrogen was increased. This universal tool (crop rotations) can be used to reduce the potential wind erosion, to reduce losses of fine silt and clay particles, to sequester C, N and nutrients, to increase the soil fertility and productivity levels. Cropping tools, such as crop rotations are universal tools that have the potential to protect soil quality and fertility and thereby contribute to agricultural sustainability. |