Erosion-preventive crop rotations and water erosion rates on undulating slopes in Lithuania

Abstract

A combination of perennial grass species and selected crop rotations can help prevent soil erosion in upland regions and minimize the risk of soil erosion and associated water pollution (to both terrestrial and aquatic ecosystems). Research data were obtained on sandy loam Eutric Albeluvisols at the Kaltinenai Research Station of the Lithuanian Institute of Agriculture on the undulating hilly topography of the Zemaiciai Uplands of Western Lithuania. The aim was to identify crops and crop rotations that would minimize soil erosion. Measured water erosion rates over 18 yr of field experiments were: 3.2–8.6 m3 ha-1 yr-1 under winter rye, 9.0–27.1 m3 ha-1 yr-1 under spring barley and 24.2–87.1 m3 ha-1 yr-1 under potatoes. Perennial grasses completely prevented water erosion, while the erosion-preventive grass-grain crop rotations (>50% grass) decreased soil losses on arable slopes of 2–5°, 5–10° and 10–14° by 75–80%. The grain-grass crop rotation (<50% grass) decreased rates by 23–24% compared to the field crop rotation. The main attributes of the proposed soil conservation systems were the careful selection of optimum erosion-preventive ecosystems (sod-forming perennial grasses or erosion-preventive crop rotations) with high erosion-resisting capabilities. These selected systems varied in response to slope gradient and thus assist erosion control and ecological stability of the undulating topography of Lithuania. These results may have wider applicability on the undulating landscapes of the temperate agricultural zone. Key words: Undulating upland topography, water erosion rates, erosion-preventive crop rotations, temperate climate