Seasonal variability and mitigation options for N2O emissions from differently managed grasslands

abonos nitrogenados application rates climatic factors cutting frequency dose d'application facteur climatique frecuencia de las cosechas frost gel grasslands groundwater table harvesting frequency helada herbage microorganisme microorganismos microorganisms nappe souterraine natural grasslands nitrogen balance nitrogen fertilizers nitrogen metabolism nitrous oxide oxyde nitreux pastizal permanente permanent grasslands permanent pastures praderas prairie permanente soil sol suelo