Assessing tree effect on total soil carbon in agroforestry parklands systems along a rainfall gradient in Burkina Faso (West Africa)

Abstract

Trees contribution in improving soil carbon is well established, but few works addressed how this was affected by a climatic gradient. This research investigated effects of Vitellaria paradoxa C. F Gaertn and Parkia biglobosa (Jacq.) Benth on total soil carbon in parklands along a rainfall gradient for recommendations of tree species which better improve soil carbon under specific climatic conditions for parklands adaptation to climate change. Total soil carbon at topsoil and subsoil layers measured using spectrophotometry infrared method, was higher when rainfall increased and were respectively (1.598 ± 0.040; 1.033 ± 0.022; 0.834 ± 0.014; 0.857 ± 0.016%). It was higher at topsoil (0.529 ± 0.015%) and subsoil (0.282 ± 0.019%) under V. paradoxa when rainfall decreased while it was higher under P. biglobosa and V. paradoxa when rainfall increased slightly. Its improvement was higher under V. paradoxa and P. biglobosa when rainfall respectively decreased and increased. A decrease trend of total soil carbon under both tree species from trunk to outside the canopy whatever rainfall levels and soil layers was observed. Tree species choice could play an important role in improving total soil carbon and crop productivity according to rainfall level for parklands adaptation to climate change.

Evaluating Sorghum bicolor (L.) Moench (Sorghum) Vigour at Juvenile Stage in Agroforestry Parklands Systems According to a Climatic Gradient in Burkina Faso (West Africa)

“…The Karite could be the tree species to promote in agroforestry parklands for improving sorghum productivity under climate change. This recommendation is in line with our result, which showed that the sorghum height was higher under the Karite than Nere at all three study sites and with the results of the research work of Coulibaly et al (2020). For each of the two tree species, the sorghum height was higher at the sites with low precipitations.…”

“…For all the zones, the sorghum height was higher at Tougouri and Nobere. Compared to Sokouraba, the soils of these sites are less fertile due to the high population, high population density, overgrazing, and low precipitation (Coulibaly et al, 2020). The limited precipitations at these sites could have led to droughts at these sites during the crop-growing season, and the higher sorghum growth is an indicator of these droughts.…”

Livestock feed resources in the West African Sahel

“…Unmanaged silvopastures are common practice across the Sahel, as trees are an integral part of grazing lands. Silvopastures improve soil fertility, forage quality, productivity and as a result animal productivity, as well as CO 2 sink of grazinglands as compared to conventional, grass‐dominated pasture lands (Bayala et al., 2007 ; Coulibaly et al., 2020 ). For instance, phosphorus and nitrogen availability has been observed to be higher under canopy trees than in areas beyond canopies in a white acacia [ Feidherbia albida (Delile) A.…”

Hydrological Investigation and Characterization of Sokouraba Watershed, Burkina Faso

“…The specific gradient of the watershed was determined by multiplying the corrected overall slope index by the square root of the watershed area. The Gravelius Compactness Index (K G ), the equivalent rectangle length (L éq ), the overall slope index (I g ), the corrected overall slope index, the gradient (D), and the Density of Drainage ge (D d ) of the watershed were determined using the following relationships (Equation 4 to 8): (4) Where K G represents the compactness index, P is the watershed perimeter and S represents the watershed area.…”

“…This rainfall deficit has led to a situation of severe water stress in the region in general and in Burkina Faso in particular, which has been affected by this continuous drought situation [3]. The country is further subject to climatic hazards that make water resources unavailable [4]. In addition, the population size has increased from 10,312,000 in 1996 to about 20,000,000 in 2019 [5,6,7].…”