Biochar

Urban regions in sub-Saharan Africa are growing significantly more rapid than their also growing rural counterparts. However, the employment perspectives in rural areas are decreasing, and thus the urban growth can become a driver for enhanced livelihoods in the rural areas.
There is a wide array of biomass utilisation pathways to mitigate greenhouse gas emissions. The characteristic of biomass, the demand for products, and the local constraints determine the sustainability of utilisation. Generic principles and criteria can be applied to the analysis of specific instances. This work develops a decision-making tool for determining the most sustainable use of biomass for carbon management. The mathematical principles are based on break-even analysis and are visualised in the form of a graphical display for transparent communication of results to decision-makers.
Soil contamination by potentially toxic elements (PTEs) has led to adverse environmental impacts. In this review, we discussed remediation of PTEs contaminated soils through immobilization techniques using different soil amendments with respect to type of element, soil, and amendment, immobilization efficiency, underlying mechanisms, and field applicability. Soil amendments such as manure, compost, biochar, clay minerals, phosphate compounds, coal fly ash, and liming materials are widely used as immobilizing agents for PTEs.
When biochar (BC) ages in soil, its properties change substantially: cation exchange capacity (CEC), surface area and porosity increase and water repellency decreases, consequently affecting the interactions with soil microorganisms. Activation of BC by organic acids may be regarded as artificial aging. Here, we study the effect of acid-activated BCs on soil microbial enzyme activities (EA) in comparison to several different control treatments without activated BC. A greenhouse pot experiment was conducted using a vineyard soil treated with multiple soil additives (four replications).
Multiple nutrient deficiencies related to severe soil fertility depletion have emerged as the major constraint to the sustainability of agriculture on a global scale. Use of biochar and biochar-compost mixtures from different alternative organic sources have been proposed as an option for improving soil fertility, restoring degraded land, and mitigating the emissions of greenhouse gasses associated with agriculture.
Previous studies already demonstrated that biochar addition reduces nitrogen (N) leaching in soil, but little information is available about its effects on N leaching and bacterial community structure under the application of organic N. This study investigated the effects of corn-straw biochar under the application of urea (250 kg N ha-1) in layered soil columns. The PCR-amplified partial 16S rRNA genes in soil were sequenced before and after biochar treatment in order to assess the change of bacterial diversity and community structure utilizing the Illumina technology.