Effect of grazing on carbon sequestration and tree growth that is developed in a silvopastoral system under wild cherry (Prunus avium L.)

Abstract Silvopastoral systems have been considered a good tool for carbon sequestrationby taking up atmospheric carbon dioxide and storing it in the soil. The effect of animal presence on carbon sequestrationin this type of agroforestrysystem has been studied recently. However, the soil carbonstorage in these systems is influenced by the stocking rate. In addition, soil fractions have been known to influence carbon storage. This study was undertaken in order to examine the effects of livestock grazing at two different stocking rates [Light Stocking Rate (LS; 4 sheep ha − 1 ) and Heavy Stocking Rate (HS; 8 sheep ha − 1 )]. This was compared with the soil chemical and physical properties of No Grazing (NG) pastures, the amount of C stored in the whole soil, in three different soil fractions (250–2000, 53–250, and Prunus avium L. The presence of animals in silvopastoral systems plays an important role in carbon sequestrationby the direct or indirect modifications of the pH, the soil bulk density, and the soil fraction proportions. The LS treatment promoted carbon sequestrationlinked to macroaggregates in the upper soil layers when compared with the HS treatment and the NG treatment. However, in deep horizons, the NG treatment enhanced the soil organic carbon storage more than did the grazing treatments and this carbon was linked to microaggregates, increasing the soil density. A better carbon concentration was found when 1 m of soil depth was evaluated in an LS treatment, but no differences were apparent in the carbon storage per hectare that were found due to a high soil bulk densityin an NG treatment.