Effects of short-duration kraaling depend on initial conditions in a mesic grassland

Short-duration overnight kraaling has been suggested as a tool for restoring degraded rangelands. However, the response of different plant functional types and communities to such intense livestock impact may vary depending on local context. We thus examined the effects of short-duration overnight kraaling on soil and vegetation characteristics in a mesic montane grassland in South Africa using paired kraal and control sites, as part of a low intensity grazing approach. Kraaling increased soil P and S, as well as soil organic matter (except when initial values were over 12%). The effect of kraaling on vegetation was strongly dependent on initial condition. Basal cover of grasses and forbs increased by approximately 50 and 15%, respectively, if sites had very low initial basal cover, but decreased by up to 15% if initial values were over 50% and 10%, respectively. Kraaling always decreased herbaceous biomass, but especially when initial values were over 2 000 kg ha(-1). In mesic grasslands, short-duration overnight kraaling is promising as a tool for rehabilitating degraded sites or fertilizing abandoned cropland, but should be avoided where the grass sward is intact. We recommend that the suitability of kraaling be evaluated per vegetation type and local context.

Automated summary

Short-duration overnight kraaling has been suggested as an effective tool for restoring degraded rangelands, but its impact on different plant types and communities may vary depending on the local context. This study found that the effects of kraaling on soil and vegetation were strongly influenced by initial conditions. Kraaling increased grass and forb cover if initial basal cover was low, but decreased it if initial values were high. In mesic grasslands, short-duration overnight kraaling can be used to rehabilitate degraded sites or fertilize abandoned cropland, but should be avoided in areas with intact grass sward. The suitability of kraaling should be evaluated based on vegetation type and local context.