Improving Soil Physical Fertility and Ecosystem Services by Sod-Based Rotation and Conservation Technology.

Integrating livestock, crops, and perennial grasses using conservation tillage has shown to benefit soil quality and crop productivity. Perennial grass such as Bahia (Paspalum notatum Flugge) in rotation with cotton (Gossypium hirsutum L.) and peanut (Arachis hypogaea L.) has advanced crop yields and economic gains in a sod-based rotation at the University of Florida IFAS-NFREC in Quincy. It also has a positive effect on pest/disease reduction. Oats (Avena sativa L.) were included as winter-cover crop to recycle nutrients in the root zone. While preliminary data on the success of such systems has been fairly well documented, the mechanisms generating these benefits within the systems require more attention. Rearrangement of soil-inherited and external-stimulated processes often occurs in soils but the effect of different loading rate of conservation-till system with short-term (2 yr) bahiagrass on soil physical properties is rarely discussed. We are addressing the impact of different row- to sod-crop sequences on soil aggregation, bulk density, penetration resistance, and porosity. Sod has an effect on soil aggregation, but the number of years of sod in the rotation affects the quantification of aggregate size distribution. Irrigated peanut in sod-based rotation yielded higher than conventional peanut in a cotton-cotton-peanut rotation; under no irrigation, both cotton and peanut had higher yields. Therefore, especially under no irrigation, sod-based system mitigated stress by improving water/nutrient-use efficiency. The sod-based rotation gives benefits above conservation tillage; crop/sod-livestock integration seeks to close nutrient cycling within the system, improve soil microbial activity, and increase soil organic matter through carbon sequestration. The impact of conservation tillage under both conventional and sod-based rotations on ecosystem services will be discussed, as well as the effects of organic matter additions from perennial grass, summer/row crops and winter/sod cover crops. Relationships between management practices and provisional/regulating/supportive services will be emphasized.