The impact of livestock grazing on the spatial pattern of vegetation in north-eastern Patagonia, Argentina

FUNK, FLAVIA; PETER, GUADALUPE; LEDER, CINTIA VANESA; LOYDI, ALEJANDRO; KRÖPFL, ALICIA INÉS; DISTEL, ROBERTO ALEJANDRO

PLANT ECOLOGY & DIVERSITY

TAYLOR & FRANCIS LTD

Lugar: Londres; Año: 2018

1755-0874

p { margin-bottom: 0.25cm; line-height: 120%; }The occurrence ofshrub patches alternating with of either bare soil or low herbaceouscover is a common feature in arid and semi-arid shrublands throughoutthe world. In physically harsh environments this spatial pattern ofvegetation may result from limited amounts of water and theprevalence of positive interactions between plants, whereas in morebenign environments it may result from livestock grazing. Wehypothesize that vegetation patchiness in the semiarid shrublands ofnorth-eastern Patagonia is a consequence of livestock grazing and notthe result of positive shrub- grass interactions. We comparedvegetation cover at three grazing intensities and the growth of arepresentative shrub and grass in the presence and absence of eachother. In grazing exclosures and moderate grazing the vegetationcover in the was higher whereas the shrub aerial cover was lower thanheavy grazing areas. On the other hand, we did not find evidence ofpositive interactions between shrub and grass life forms. Our resultswere consistent with the hypothesis that livestock grazing is aprimary driver of vegetation patch formation in the semiaridecosystems of eastern Patagonia. Revealing the origin of vegetationpatchiness in semiarid ecosystems has important theoretical andpractical implications, as discussed in study.