Africa, specifically Nigeria, has witnessed a dramatic increase in population over the last century, prompting efforts to ensure sustainable food production and quality. Concerns for soil sustainability and food security have led to the exploration of cost-effective methods, such as biochar, to enhance soil quality. Researchers in Nigeria and Africa as a whole have investigated biochar’s potential to improve soil fertility and crop performance across various agroecological zones. This paper aims to review recent biochar research priorities on soil fertility and crop performance with an emphasis on various sole biochar applications and combinations with fertilizers to determine the research gaps that need to be developed more in biochar research in Nigeria. From the papers reviewed, sole biochar applications and biochar + macronutrients and biochar + manure combinations were studied more dominantly, while biochar + micronutrients research projects were scanty despite their low content in the semi-arid soils of Nigeria. The studies were spread across the country with the majority taking place in derived savanna and humid forest, while Sudan savanna and Sahel savanna received less research attention despite being characterized by a low-fertile soil and vast area of land. Research involving BC in the context of Sahel savanna (SLS) and Sudan savanna (SS) soils is strongly encouraged in Nigeria. This research should encompass a wide range of investigations, including sole BC applications and combinations of BC with macronutrients, micronutrients, and manure, as well as exploring its potential as a slow-release fertilizer. Incorporating exclusive biochar in substantial amounts appears economically unfeasible within the context of local biochar production. However, it can be utilized in the synthesis of slow-release fertilizers, requiring smaller quantities and potentially offering cost-effectiveness. This approach enhances soil condition and crop productivity. Challenges are faced due to less commercial production as a result of inadequate power and structural facilities. Exploring the modification of local biochar for slow-release fertilizers through future research offers potential profitability.

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

Accurate forest biomass estimation is essential for quantifying carbon stocks, guiding sustainable forest management, and informing climate change mitigation strategies. Kenya’s forests are diverse, ranging from Afromontane and mangrove ecosystems to dryland woodlands and plantations, each presenting unique challenges for biomass measurement. This review synthesizes literature on field-based, remote sensing, and machine learning approaches applied in Kenya, highlighting their effectiveness, limitations, and integration potential. A systematic search across multiple databases identified peer-reviewed studies published in the last decade, screened against defined inclusion and exclusion criteria. The main findings are (1) Field-based techniques (e.g., allometric equations, quadrat sampling) provide reliable and site-specific estimates but are labor-intensive and limited in scalability. (2) Remote sensing methods (LiDAR, UAVs, multispectral and radar imagery) enable large-scale and repeat assessments, though they require extensive calibration and investment. (3) Machine learning and hybrid approaches enhance prediction accuracy by integrating multi-source data, but their success depends on data availability and methodological harmonization. This review identifies opportunities for integrating field and remote sensing data with machine learning to strengthen biomass monitoring. Establishing a national biomass inventory, supported by robust policy frameworks, is critical to align Kenya’s forest management with global climate and biodiversity goals.

Jelen tanulmányban egy egyszerű módszert dolgoztunk ki a felületi ioncsere-folyamatok vizsgálatára -ahol a talajrészecskék felületéről a megkötött foszfátionok által távozó hidrogén-és hidroxidionok mennyiségét tudtuk mérni. Ezt a fajta vizsgálatot a szakirodalomban pH-változással követték -ami sokkal kevésbé pontos eredményeket ad -mint a felületi ionmérleg számítása. A talajmintákat KH2PO4oldattal rázattuk három ismétlésben 0 -4 -8 -12 -16 -20 -24 -32 -40 -48 -56 -64 -72 -88 és 100 mg/l P-tartalommal. Két óra rázást követően a mintákat centrifugáltuk és a P-tartalmat fotometriás módszerrel határoztuk meg. Az egyensúlyi oldatokfoszforkoncentrációját a talajfoszfor adszorpciós izotermájának meghatározására használtuk. Az elválasztott egyensúlyi oldatokból és az adszorpcióhoz használt eredeti oldatokból a hidrogénion-tartalmat a laboratóriumunkban tervezett nagy érzékenységű potenciometriás titrátorral -0,01 M NaOH oldat hozzáadásával határoztuk meg. A kis mennyiségű híg oldatokra kapott -más módszerekkel nehezen értékelhető titrálási görbéket egy saját fejlesztésű számítógépes programmal értékeltük ki a görbe inflexiós pontjainak -azaz az ekvivalenciapontoknak a meghatározására. Az oldatból hiányzó hidrogénionok mennyiségét a megkötött foszfor mennyiségének függvényében ábrázoltuk. Az adatok azt mutatják -hogy a talajhoz adott KH2PO4-oldat hidrogénion-tartalmának az egyensúlyi állapot után mért változása a megkötött foszfátionok mólszámának háromszorosával egyenlő. Az illesztett egyenes meredeksége 0,35, a korrelációs együttható pedig 0,95 volt. Ez azt jelenti -hogy minden egyes mólnyi megkötött foszfáthoz három mólnyi OH-ion deszorpciós folyamata vagy három mólnyi megkötött H+-ionnak megfelelő mennyiség társul. Formálisan ez a mólarány kifejezi a töltés nélküli foszforsavmolekulák kötődését a talajfelszínen. Méréseink alapján az adott körülmények között a különböző hidrogén-foszfátionok megkötésére többféle kötődési mechanizmus feltételezhető. Az eredmények azt mutatják -hogy egyes kémiai reakciók kizárhatók -bár mások megállapíthatók. A foszfátformák adszorpciója során a talajfelszínen csak ioncsere-reakciók játszódnak le -amelyek nem járnak felületi töltésváltozással -és a különböző hidrogén-foszfát anionok hidroxidionokra cserélődnek.

According to climate projections, the Pannonian region is expected to experience an increasing frequency of drought events. This trend affects not only agricultural areas but also natural grasslands. The Festuca wagneri species, selected for this study, is a dominant and well-adapted grass in dry natural habitats. A total of 54 Festuca wagneri individuals were examined across three soil types: sand, loam, and clay. In each soil type, 18 plants were assessed for drought tolerance. Water was applied at three dosage levels: 200, 300, and 400 mL. The experiment was conducted between 4 April and 18 July 2024, during which the total weight of the pots and the amount of drained water were measured regularly. All data processing and statistical analyses were performed in R version 4.3.2. A three-way factorial ANOVA was used to evaluate main and interaction effects. Model residuals were tested for normality (Shapiro–Wilk test) and homoscedasticity using diagnostic plots. The results showed that Festuca wagneri individuals tolerated even the lowest soil moisture levels induced by low water-holding capacity of the soil and low water input. This indicates that the species can be effectively used in grassland management and restoration under future climate change scenarios. The main differences were observed among soil types, highlighting the crucial importance of soil structure when establishing this species. Loam soils, already near optimal, respond best to moderate.