Managing biogeocycles in forage and cropping systems for environmental and economic benefits

Background: Most of modern agriculture and mono-crop production systems rely on inorganic fertilizer inputs for crop nutrition, a paradigm shift from conventional systems that used organic inputs such as crop residues and animal waste through mixed cropping with legumes and livestock. Lower organic carbon status and high N and P fertilization costs are common production constraints in mechanically managed systems, a common cultivation practice in the Great Plains of USA, Texas and other parts of the world. Moreover, the N use efficiency (NUE) in most cereals and forages is about 30-50%. Significant proportion of applied N in agricultural systems is lost as nitrate through leaching, ammonia volatilization and NOx gas emission, with consequences on water quality and climate. Food production with minimal environmental consequences will be further complicated by increased demand for food and global climate change. Prolonged droughts (moisture stress conditions) are predicted to persist for decades in Southern USA and several other parts of the world and overall global soil moisture status is projected to decrease. Decreased soil moisture status over long time can impact C, N and P biogeocycling and accelerate soil fertility loss and nutrient imbalances over time. Not much is known about the plant-microbe interactions and C, N and P cycling under prolong droughts..........

Managing biogeocycles in forage and cropping systems for environmental and economic benefits Grant