Enhancing plant utilization of livestock manure: a cropping system perspective

摘要

This paper highlights some key features of cropping systems coupling quantitative approaches and experimental data collected on poliennial experiment fertilized with pig slurry in the area of the lower Po Valley. In areas with intensive livestock activities the contamination of surface and ground water is a crucial environmental concern. The type and the sequence in which crops are cultivated play an important role in determining sustainability of land use. Through the choice of proper crop rotations an efficient use of natural resources maybe achieved, nutrient uptake can be optimized and losses of nutrients can be kept at a tolerable level. The aims of maximizing nutrient uptake by the plants and diminishing nutrient leaching can be pursued by the adoption of the so-called "intensive cropping". Increasing the time and the extent of green leaf covering during the growing season leads to full use of solar radiation, efficient use of water resources and maximum nutrient uptake by the crops. Conversely, cropping systems that leave the soil uncovered for long periods between subsequent crops, may lead to high risk of nitrate leaching even when fertilization levels are moderate. Consequently, farmers should be encouraged to the adoption of croppingsystems assuring a maximum leaf cover during the growing season.