Cadmium-contaminated soil significantly threatens global food security and human health. This scenario gives rise to significant worries regarding widespread environmental pollution. Biochar and arbuscular mycorrhizal fungi (AMF) can effectively immobilize cadmium in the soil in an environmentally friendly way. Existing studies have separately focused on the feasibility of each in remediating polluted soil. However, their association during the remediation of cadmium-polluted soils remains unclear. This review paper aims to elucidate the potential of biochar, in conjunction with AMF, as a strategy to remediate soil contaminated with cadmium. This paper comprehensively analyzes the current understanding of the processes in cadmium immobilization in the soil environment by examining the synergistic interactions between biochar and AMF. Key factors influencing the efficacy of this approach, such as biochar properties, AMF species, and soil conditions, are discussed. The influences of biochar–AMF interactions on plant growth, nutrient uptake, and overall ecosystem health in cadmium-contaminated environments are highlighted. This review indicates that combining biochar and AMF can improve cadmium immobilization. The presence of AMF in the soil can create numerous binding sites on biochar for cadmium ions, effectively immobilizing them in the soil. Insights from this review contribute to a deeper understanding of sustainable and eco-friendly approaches to remediate cadmium-contaminated soils, offering potential applications in agriculture and environmental management.

Electrical and electronic waste (E-waste) production are not only increasing enormously every day but also continue to pollute water and soil which are very essential elements to assert life completely and crucial to sustainable development and prosperity. With the emergence of information and communication technology (ICT), people are excited to explore emerging innovations, contributing robust demand for and the use of today’s electrical and electronic equipment (EEE). Due to the lack of a precise management and disposal approach, the expired EEE are rapidly discarded as E-waste in mass and dumped in an inapt landfill or stowed where large soil areas are available, such as near industries, institutions, etc. In addition, the majority of those areas are near to the water table and other watercourses. These induce soil and water to be unsuitable for different purposes due to harmful toxic metals. Consequently, they are leading harsh health and environmental problems in developing countries and to some extent in developed countries. This review paper compiles E-waste categories and their effects, as well as soil and water contamination processes, and also advocates viable remediation technology.

Recently, rampant eutrophication induced by phosphorus enrichment in water has been attracting attention worldwide. However, the mechanisms by which phosphate can be eliminated from the aqueous environment remain unclear. This study was aimed at investigating the adsorption performance and regulation mechanisms of the zeolite-biochar composite for removing phosphate from an aqueous environment. To do this, physicochemical properties of the zeolite-biochar composite were assessed by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), Brunauer–Emmett–Teller (BET) specific surface area (SSA) analyzer, and transmission electron microscopy (TEM). Adsorption tests were performed to evaluate the adsorption ability of the composite material for mitigating excess phosphorus in the aqueous environment. The findings evinced that the phosphorus removed by PZC 7:3 (pyrolyzed zeolite and corn straw at a mass ratio of 7:3) can reach 90% of that removed by biochar. The maximum adsorption capacities of zeolite, biochar, and PZC 7:3 were 0.69, 3.60, and 2.41 mg/g, respectively. The main mechanism of phosphate removal by PZC 7:3 was the formation of thin-film amorphous calcium-magnesium phosphate compounds through ligand exchange. This study suggests that PZC 7:3 is a viable adsorbent for the removal of phosphate from aquatic systems.

Flooding can have an effect on each thing of our lives, including road transportation. This study investigated the causes and the effects of flooding on road transportation in Rwanda, Kigali city and contributed to the mitigation measures. The data were collected by administering 150 questionnaires on the respondents within the study area and by physical survey. The hypotheses were formulated and tested using the statistical method of student’s t- test and the data displayed a significant difference (P<0.05). The results of this study revealed that heavy rains, poor drainage systems, illegal disposal of waste in drains, and poor construction and maintenance of roads are the main causes of road flooding in the city of Kigali. The effects of floods on road transportation include traffic jam and increased travel time, damage to road structures, blockage of drains and traffic accidents in the study area. The study recommends green storm water infrastructure practices, good road construction works, controlled dumping sites, the construction and maintenance of drainage systems and an immediate government response to the threat of flooding to address the challenges of flooding on road transportation in the city of Kigali.