Informations et ressources scientifiques
sur le développement des zones arides et semi-arides

Accueil du site → Master → Afrique du Sud → 2021 → Impacts of foraging behavior by Cape porcupines and their effects on nutrient cycling in mesic savannas.

University of KwaZulu-Natal (2021)

Impacts of foraging behavior by Cape porcupines and their effects on nutrient cycling in mesic savannas.

Kraai, Unathi Masiobi

Titre : Impacts of foraging behavior by Cape porcupines and their effects on nutrient cycling in mesic savannas.

Auteur : Kraai, Unathi Masiobi

Université de soutenance : University of KwaZulu-Natal

Grade : Master of Science (MS) Ecology 2021

Résumé partiel
Through feeding and associated activities, herbivores play a major role in determining the structure of savannas. The Cape porcupine (Hystrix africaeaustralis) is a semi-fossorial, large (ca. 12 kg) herbivorous rodent with a generalist foraging strategy that feeds on plant parts occurring above- and below ground. Subterranean foraging by porcupine may influence biotic and abiotic processes in that area. The extent of soil and vegetation perturbation may be pervasive on the landscape so that these animals may be considered as ecosystem engineers. The digging activities of ecosystem engineers are significant as they influence soil properties (e.g. nutrient cycling) including germination of trapped seeds and establishment of seedlings. These changes may occur at small and large scale on a landscape. The utilisation of woody vegetation and ecosystem engineering by such animals, particularly by shy and nocturnal species, is understudied in African savannas. The study was aimed at : (1) quantifying the extent of herbivory by the porcupines on target trees during the wet and dry season in three mesic savanna sites, and (2) evaluating the effects of Cape porcupines’ digging on nutrient cycling (total carbon and total nitrogen) and quantify establishment of vegetation on the mounds. Sampling was undertaken at three mesic savanna sites in South Africa : (i) Roodeplaat Farm in Gauteng Province ; (ii) Goss Game Farm ; and (iii) Bisley Valley Nature Reserve, both in KwaZulu-Natal Province. I used 30 m × 30 m plots to quantify porcupine foraging holes and bark damage on adult trees at Roodeplaat and Goss while 10 m × 10 m plots were used at Bisley where porcupines foraged on seedlings and saplings of woody plants. I also collected porcupine dung samples over the dry and wet season for micromorphological examination of porcupine diet. I collected soil samples from the mound soil of foraging holes and from adjacent locations within 0.5 m of the hole for analysis of amounts of total carbon and total nitrogen. Measurements of foraging holes comprised of two perpendicular diameters on the soil surface and the maximum depth.

Présentation

Version intégrale (2,7 Mb)

Page publiée le 22 avril 2022