Influence of grazing and precipitation on ecosystem carbon cycling in a mixed-grass prairie

摘要: Grasslands sequester and store large amounts of soil carbon, which is primarily controlled by herbivory precipitation. However, few studies have examined the combined effects these two factors quantified how they control carbon cycling in temperate grasslands. The objective this study was to quantify grazing intensity affects magnitudes patterns net CO2 exchange mixed-grass prairie, largest native grassland ecosystem North America. conducted during contrasting precipitation years (dry vs. wet summer), allowed investigation interaction between on exchange. Our three regimes been place for 20 consist light heavy ungrazed exclosures. Ecosystem rates were strongly influenced changes summer Decreasing reduced respiration (RE) 45%, gross production (GEP) 75%, (NEE) 70%. lightly grazed pastures had greatest RE, GEP, NEE summer; however, did not differ treatments dry summer. These results indicate that interact influence prairie ecosystems.