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

Accueil du site → Master → Afrique du Sud → 2018 → Analysis of global gully characteristics and the impacts of gabions and grass on sediments and carbon storage

University of KwaZulu-Natal (2018)

Analysis of global gully characteristics and the impacts of gabions and grass on sediments and carbon storage

Dube, Hastings Bangani.

Titre : Analysis of global gully characteristics and the impacts of gabions and grass on sediments and carbon storage

Auteur : Dube, Hastings Bangani.

Université de soutenance : University of KwaZulu-Natal

Grade : Masters of Science in Soil Science 2018

Résumé partiel
Gully erosion has immediate and long-term negative impact on the environment. Rehabilitation effectiveness depends on gully characteristics and the trapped sediments, which can help to sequester carbon (C) and mitigate climate change. The C from the sediments, if not trapped, is either eroded into the ocean or mineralized to CO2, which accumulates into the atmosphere and contribute to global warming. The objectives of the study were to evaluate (1) the main factors that affect gully characteristics at global scale, and (2) the potential impact of gabions and grass, as gully rehabilitation techniques, on sediment retention and C sequestration. In the global analysis of permanent gullies, available literature on factors affecting characteristics of gullies was explored. Data was collected from online search engines such as Google Scholar and electronic bibliographic databases (e.g. Science Direct, Springerlink). A database on published gully channel parameters such as volume (V), length (L), width (W), depth (D), W:D ratio (indicator of incision shape), top-view (A) and crosssectional areas (Ac) for 435 permanent gullies across the world was compiled and used to analyse for the impacts of different climates (tropical, sub-tropical and temperate), land cover, terrain altitude and slope, soil texture and bulk density on the channel dimensions. Potential impact of gully rehabilitation on sediment and carbon storage was evaluated in Okhombe area near the Drankensburg mountain range in KwaZulu-Natal province, South Africa. The rehabilitation techniques used in the studied gully was a combination of stone-checks and vegetative methods. Soil samples (n= 206)) were collected from the 0-5, 5-15, 15-30, 30-60, 60-90 and 90-120 cm depth of lower, mid and upper gully positions, and adjacent positions outside the gully. These soil samples were analysed for particle size distribution, total organic carbon and nitrogen content (OCC, ONC) and soil bulk density.

Présentation

Version intégrale (1,3 Mb)

Page publiée le 5 janvier 2021