Salt stress has been a major problem in the soils of the world. Semi-arid and arid soils are the most affected and bring about adverse crop productivity and yield especially in susceptible species. Salinity is usually denoted with electrical conductivity (EC) equal to or greater than 4 deci Siemens per meter (dS/m). With expanding areas affected by salinity, especially with increasing sea water level and incursion of land, rise in salty water table is eminent as consequences of climate change. Sustainable remediation of soil salinity is becoming a major concern, especially in the field of agriculture and climate change mitigation. Remediation of saline soil with application of organic amendments has shown positive results with the added advantage of carbon build up in the soil. Recently with the focus on biochar as one of the recent soil conditioners and amendment, many researchers have tried to find out its remediating capacity on soil salinity. This article will focus on how biochar affects soil salinity with much emphasis on cation exchange capacity (CEC) and anion exchange capacity (AEC). Results from researchers showed that biochar remediates soil salinity due to its inherent characteristics like high CEC and possession of AEC that deprives both cations and anions that form salt in the soil. This positively favour the thrival of crops under salt stress by boosting K⁺ availability, high salt sorption capacity, increased plant water intake, accelerated transpiration, lowered soil EC, increased soil accessible nutrients, increased soil moisture saving, optimizes the water-salt balance of the soil during saline irrigation, extended life span of plant which all favour crop performance. Future studies should explore synergistic effects of combining biochar with other soil management practices like drainage systems to enhance salinity mitigation and crop performance. Additionally, nano-biochar represents a promising direction in biochar development, with more possible potential for salinity amelioration due to higher surface area compared to biochar. While biochar has the potential to mitigate this issue, research on its application in African contexts is limited. More localized studies are needed to develop effective biochar solutions tailored to specific African environments and agricultural practices. Graphical abstract

A decline in rainfall as a source of agricultural water has affected and will continue to affect sustainable crop production globally including in Hungary. Conservation of the greatest water reservoir is important for the sustainable development of agriculture in Hungary. The objective of this study was to evaluate the effects of the different tillage methods on soil moisture content, grain yield, and root weight of wheat (Triticum aestivum) and sunflower (Helianthus annuus) under rainfed conditions. A field study was conducted at the Józsefmajor Experimental and Training Farm (JM) of the Hungarian University of Agriculture and Life Sciences near Hatvan. The experiment consisted of six tillage treatments: disking (D, 16 cm), shallow cultivation (SC, 20 cm), no-till (NT), deep cultivation (DC, 25 cm), loosening (L, 45 cm), and plowing (P, 30 cm). Soil moisture content (SMC) was measured monthly, and grain yield and root weight were measured at the end of the cropping period. Our results showed no significant difference in SMC between conservation and conventional tillage methods in 2018. However, in 2021, greater SMC was significantly conserved under NT compared to P. Regarding the sampling date, a significant increase in moisture with time was observed. A significantly lower SMC was observed on 3 June 2019 between L and D. while on the 9 September 2020, SMC significantly differed between P and all the other treatments (D, SC, NT, DC, and L). Interestingly in 2018, SMC was significantly lower at 10–20 cm depth between L and D. Notably the effect of depth on SMC was observed as moisture significantly increased with increasing depth in all tillage treatments. Root weight was greatest at DC (1.54 t ha⁻¹) in 2018 and under L (3.89 t ha⁻¹) in 2021. Similarly, wheat grain yield was greatest at DC (2.48 t ha⁻¹) in 2018, while sunflower yield in 2021 was greatest at L (3.86 t ha⁻¹). It is comprehensible that conservation tillage methods such as L and NT can increase SMC and grain yield.

Although numerous studies have reported an increased yield upon adoption to improved agricultural practices (IAPs), yet smallholder farmers face limited access to this information. The objective of this study was to assess smallholder farmers' awareness and adoption of IAPs. A total of 206 active and registered households were surveyed by mixed sampling in the Mbeya region. The data was collected from smallholder farmers using the ODK collect tool through a well-structured questionnaire. The probit model and One-way ANOVA test were performed to identify predictor variables. Results pointed out that farming period, top dressing, flood exposure, fallowing time, soil information on IAPs, and knowledge about soil type showed a significant difference (p < 0.05) on the farmers’ adoption of IAPs. Moreover, 81% and 72% of the smallholder farmers surveyed showed a lack of awareness regarding the specific soil type and general soil information related to their farmland, respectively. Only 24% of farmers relied on agricultural experts (extension service officers) to get information on IAPs whereas 65% of the respondents were unfamiliar with neither Agricultural Extension Officers, non-governmental organizations (NGOs), Tanzania Agricultural Research Institute (TARI), nor Researchers from Higher Learning Institution (RHLI). About 59% of the female-headed households were found to have a better soil information on IAPs than men at a 5% significant level. Age and education level do not affect farmers’ adoption of IAPs with 72.5% of respondents motivated to adopt various IAPs in the surveyed area. This study highlights the need to highly consider agricultural extension officers as important agents in linking smallholder farmers with NGOs programs, agricultural research findings, and government programs to improve their livelihood. Graphical abstract

Anthropogenic activities around local villages in mesic savanna landscapes of West Africa have resulted in soil improvement and forest establishment outside their climatic zones. Such unique ‘forest islands’ have been reported to provide ecosystem services including biodiversity conservation. However, the science underpinning their formations is limitedly studied. In 2015 and with funding support from the Royal Society-DFID (now FCDO), we set out to investigate the biogeochemistry of the forest islands in comparison with adjacent natural savanna and farmlands across 11 locations in Burkina Faso, Ghana and Nigeria. Our results showed that the forest islands do not differ significantly from the adjoining ecosystems in soil mineralogy implying that their formation was anthropogenically driven. We observed greater soil organic carbon and nutrient distributions in the forest islands, which also had more stable macro (>500 μm) and meso-aggregates (500–250 μm) than the adjoining agricultural lands. We found that soil micro-aggregate (250–53 μm) stability was climate (precipitation) driven in the West African ecosystems while meso- and macro-aggregate stability was land-use driven. In one of the unique forest islands we studied in the Mole National Park of Ghana, we found its mineral-associated organic carbon over 40% greater than the adjoining natural savanna with potential implications for the achievement of the global initiative of the ‘4p1000’ in West Africa. We conclude that the North–South–South research collaboration has established clearly, the science underlying the age-long West African forest island phenomenon and has, among many successes, led to capacity building of young scientists driving cutting-edge research in climate change adaptation and food systems transformation in the sub-region.

The conservation tillage method is a more holistic method introduced in Hungary two decades ago. Its environmental benefits in agriculture were widely studied and documented. The impact of conservation tillage on soil compaction and penetration resistance remains debated, necessitating further research to clarify its long-term effects in different soil types and cropping systems. The present study evaluates the impact on soil penetration resistance following 16 years of implementation of six distinct tillage practices. The study was conducted at Józsefmajor Experimental and Training Farm (JM) of the Hungarian University of Agriculture and Life Sciences near Hatvan. The study employed a randomized complete block design (RCBD) to evaluate six distinct tillage methods. These methods encompassed disking (D) at 12–14 cm depth, shallow cultivation (SC) at 18–20 cm depth, no-tilling (NT), deep cultivation (DC) at 22–25 cm depth, loosening (L) at 40–45 cm depth, and plowing (P) at 28–30 cm depth. In this study, soil compaction was assessed by measuring soil penetration resistance (SPR) at different depths (0–50 cm) and periods of the cropping year. Disking and NT significantly increased SPR between 10 and 20 cm, likely due to increased soil densification and reduced porosity in the absence of deep soil disturbance. While under sunflower cropping season significantly higher SPR was measured. In March 2021, the SPR at D and NT differed significantly from other measurement dates (September, October, November, and April). Regarding the difference between the depths, SPR increased with increasing depths in all treatment plots. The study findings revealed that NT and D tillage methods significantly increased soil penetration resistance in both cropping years, whereas L and P reduced SPR and enhanced the soil moisture storage potential of the soil particularly for the sunflower cropping period. The significance of the Spearman correlations observed suggested that SPR could be a valuable indicator of root growth potential under certain tillage conditions. Based on our results, we recommend the adoption of occasional deep soil loosening for reduced tillage systems (SC, D, DC, and NT) for both wheat and sunflower. This will create a compact-free zone for greater crop root proliferation, nutrient access, and SMC storage.

The enforcement of the European Union Deforestation Regulation (EUDR) may reduce the supply of natural rubber to the European Union (EU), potentially leading to price increases due to the inelastic nature of rubber demand. This study assesses the potential financial implications for smallholder producers in Ghana, considering both the opportunities and risks associated with the evolving regulatory environment under EUDR and local market access conditions. A cost–benefit analysis (CBA) was conducted to evaluate the impact of different EUDR-related export decline scenarios on the net present value (NPV) of a standard 4-hectare plantation. The results suggest that even a minor 2.5% decline in global exports to the EU could increase the NPV by 17% for an independent compliant producer. However, a simulated COVID-19-like crisis in the fifth year of production leads to a 20% decline in NPV, reflecting vulnerability to external shocks. Based on these findings, the study identifies two priorities. This first is improving the coordination and harmonization of compliance efforts across the value chain to enable more producers to benefit from potential EUDR-related price increases. The recent creation of the Association of Natural Rubber Actors of Ghana (ANRAG) presents an opportunity to support such collective mechanisms. Second, minimizing losses during demand shocks requires the Tree Crops Development Authority (TCDA) to establish clear rules and transparent reporting for authorizing unprocessed rubber exports when factories reduce purchases due to low international prices—thus preserving market access for vulnerable producers. Together, these approaches would ensure that the potential benefits of the EUDR are realized inclusively, remain stable despite market downturns, and do not undermine value addition in domestic processing factories.