Impacts of land use and topography on soil organic carbon in a Mediterranean landscape (north-western Tunisia)

Abstract

Abstract. This study evaluated the impact of land use and landscape forms on SOC within the Wadi Beja watershed in north-western Tunisia. A soil spectral library was set to assess the variation of the SOC of 1440 soil samples from four land use types (field crops, permanent crops, forest, and grazing land), three slope categories (flat, moderate, and steep) and two aspects (north- and south-facing). For field crops, only one factor – slope – significantly affected SOC, which SOC levels in north-facing areas appear higher in flat areas (0.75 %) than in hilly areas (0.51%). However, in south-facing areas, SOC levels were also higher in flat areas (0.74 %) than in hilly areas (0.50 %). For permanent crops, which was interplanted with field crops, the slope significantly affected SOC levels where SOC levels have been improved to 0.97 % in flat north facing and 0.96 % in flat south-facing areas, which are higher than hilly south – and north-facing areas (0.79 %). In the grazing land use system, both investigated factors – aspect and slope – significantly affected the SOC levels which, SOC levels were significantly higher in flat areas (north-facing: 0.84 %, south-facing: 0.77 %), compared to hilly areas (north-facing: 0.61 %, south-facing: 0.56 %). For the forest, none of the factors had a significant effect on the SOC, which they are higher in flat areas (north-facing: 1.15 %, south-facing: 1.14 %), compared to 1.09 % in north and 1.07 % in south-facing in steep areas. This study highlights the importance of the land use and landscape forms in determining the variation in SOC levels.

Carbon management Index under different land uses of Conoor region of Western ghats in Tamil Nadu

“…Land-use change from native forest land to other land resulted in the degradation of soil and its organic carbon concentration (Jendoubi et al, 2019). Native lands (FOR), owing to their carbon inputs and tree architecture, sequester enough carbon within their ecosystem, resulting in higher TOC in FOR soils (Nath et al, 2018) than in other ecosystems.…”

Weed Types and Dynamics Associations with Catena Landscape Positions: Smallholder Farmers’ Knowledge and Perception in Zimbabwe

“…e average landholding is less than 3 ha per household [30]. Homestead settlements were built on a crest along the road for easy access to transport communication or foothills where there is good drainage [31]. e crest/upper catena is generally characterised by sandy soils, and while most outer fields are on the lower catena, mainly, located close to the water source and used for both field crop, and horticultural production and grazing.…”