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Abstract Soil erosion has become one of the most common environmental problems and threatens food security. This study assessed the short‐term effect of tillage and mulch on soil redistribution using the beryllium‐7 method, soil moisture distribution, and soil organic carbon loss through soil erosion in typical agroecological conditions of Benin. The experiment was conducted on acrisols (at Dan) and ferralsols (at Za‐zounmè) in central Benin. Three tillage practices slope ridging (SR), contour ridging (CR), and no‐tillage (NT), and three mulch doses 0 (0 M), 3 (3 M), and 7 t ha−1 (7 M) on soil erosion under maize were investigated. The results showed a tillage and mulch interaction significantly (p

Abstract Objectives: To investigate the factors associated with Pseudomonas aeruginosa isolates in intensive care unit (ICU) before and after an antimicrobial stewardship program. Materials: Monocentric retrospective cohort study. Patients admitted to the ICU in 2007–2014 were included. Characteristics of P. aeruginosa patients were compared to overall ICU population. Clinical and microbiological characteristics of P. aeruginosa patients before (2007–2010) and after (2011–2014) the beginning of the AMP were compared. Results: Overall, 5,263 patients were admitted to the ICU, 274/5,263 (5%) had a P. aeruginosa isolate during their staying. In 2011–2014, the percentage P. aeruginosa isolates reduced (7% vs 4%, P ≤ .0001). Patients with P. aeruginosa had higher rates of in-hospital death (43% vs 20%, P < .0001) than overall ICU population. In 2011–2014, rates of multidrug-resistant (11% vs 2%, P = .0020), fluoroquinolone-resistant (35% vs 12%, P < .0001), and ceftazidime-resistant (23% vs 8%, P = .0009) P. aeruginosa reduced. Treatments by fluoroquinolones (36% vs 4%, P ≤ .0001), carbapenems (27% vs 9%, P = .0002), and third-generation cephalosporins (49% vs 12%, P ≤ .0001) before P. aeruginosa isolation reduced while piperacillin (0% vs 13%, P < .0001) and trimethoprim-sulfamethoxazole (8% vs 26%, P = .0023) increased. Endotracheal intubation reduced in 2011–2014 (61% vs 35%, P < .0001). Fluoroquinolone-resistance was higher in patients who received endotracheal intubation (29% vs 17%, P = .0197). Previous treatment by fluoroquinolones (OR = 2.94, P = .0020) and study period (2007–2010) (OR = 2.07, P = .0462) were the factors associated with fluoroquinolone-resistance at the multivariate analysis. Conclusions: Antibiotic susceptibility in P. aeruginosa isolates was restored after the reduction of endotracheal intubation, fluoroquinolones, carbapenems, and third-generation cephalosporins and the increased use of molecules with a low ecological footprint, as piperacillin and trimethoprim-sulfamethoxazole.

Abstract Background Top-soil microbiomes make a vital contribution to the Earth’s ecology and harbor an extraordinarily high biodiversity. They are also key players in many ecosystem services, particularly in arid regions of the globe such as the African continent. While several recent studies have documented patterns in global soil microbial ecology, these are largely biased towards widely studied regions and rely on models to interpolate the microbial diversity of other regions where there is low data coverage. This is the case for sub-Saharan Africa, where the number of regional microbial studies is very low in comparison to other continents. Results The aim of this study was to conduct an extensive biogeographical survey of sub-Saharan Africa’s top-soil microbiomes, with a specific focus on investigating the environmental drivers of microbial ecology across the region. In this study, we sampled 810 sample sites across 9 sub-Saharan African countries and used taxonomic barcoding to profile the microbial ecology of these regions. Our results showed that the sub-Saharan nations included in the study harbor qualitatively distinguishable soil microbiomes. In addition, using soil chemistry and climatic data extracted from the same sites, we demonstrated that the top-soil microbiome is shaped by a broad range of environmental factors, most notably pH, precipitation, and temperature. Through the use of structural equation modeling, we also developed a model to predict how soil microbial biodiversity in sub-Saharan Africa might be affected by future climate change scenarios. This model predicted that the soil microbial biodiversity of countries such as Kenya will be negatively affected by increased temperatures and decreased precipitation, while the fungal biodiversity of Benin will benefit from the increase in annual precipitation. Conclusion This study represents the most extensive biogeographical survey of sub-Saharan top-soil microbiomes to date. Importantly, this study has allowed us to identify countries in sub-Saharan Africa that might be particularly vulnerable to losses in soil microbial ecology and productivity due to climate change. Considering the reliance of many economies in the region on rain-fed agriculture, this study provides crucial information to support conservation efforts in the countries that will be most heavily impacted by climate change. Video Abstract

Soil organic carbon storage in agricultural soil constitutes a crucial potential for sustainable agricultural productivity and climate change mitigation. This paper aimed at assessing soil organic carbon stock and its distribution in three particle size fractions across five cropping systems located in Kiti sub-watershed in Benin. Soil samples were collected using a grid sampling method on four soil depth layers: 0–10, 10–20, 20–30 and 30–40 cm in five cropping systems maize–cotton relay cropping (MCRC), yam–maize intercropping (YMI), teak plantation (TP), 5-year fallow (5YF) and above 10-year fallow (Ab10YF) from July to August 2017. Soil organic carbon stock (C stock) was estimated for the different soil layers and particle-size fractionation of soil organic matter was performed considering three fractions. The fractions coarse particulate organic matter (cPOM: 250–2000 µm), fine particulate organic matter (fPOM: 53–250 µm) and non-particulate organic matter (NOM: −1, while cultivated land under tillage MCRC depicted the lowest, C stock 11.48 Mg C·ha−1. The three organic carbon fractions showed a significant variation across the cropping systems with the NOM fraction holding the largest contribution to total soil organic carbon for all the cropping systems, ranging between 3.40 and 7.99 g/kg. The cPOM and fPOM were the most influenced by cropping systems with the highest concentration observed in Ab10YF and 5YF. The findings provide insights for upscaling farm management practices towards sustainable agricultural systems with substantial potential for carbon sequestration and climate change mitigation.

Nitrogen deficiency is a major factor limiting crop production in most African agricultural soils. As legume, soybean can obtain a significant amount of its N requirement through symbiotic N2 fixation when inoculated with effective and compatible Bradyrhizobium strains. An on farmer's fields' study was carried out in Northern and Centre Benin to determine the effectiveness of Bradyrhizobium japonicum strains introduced in Benin cropping systems. Five inoculations treatments (control, FA3, STM3043, STM3045 and USDA110), two phosphorus levels (0 and 50 kg of P2O5 ha-1) arranged in split plot design were established in twelve farmers' fields. Each farmer represented one replication. Results indicated that inoculation with different Bradyrhizobia strains improved significantly (p < 0.001 to p < 0.05) height, grain, biomass yield, nodulation, and nitrogen uptake of soybean but less than treatments where phosphorus application was combined to rhizobial inoculation. The most efficient strains identified were FA3 and STM3043 respectively in Northern and Centre Benin. In Northern Benin, the strain FA3 contributed to the increasing of 73% of the grain yield and 62% of the straw yield compared to the control, while in the Centre Benin the strain STM3043 was found to contribute to the increasing of 60% and 66% respectively of the grain and straw yields. Both strains FA3 and STM3043 could be used in cropping systems for improving soybean productivity in Benin. [ABSTRACT FROM AUTHOR]