Advances in research on the use of biochar in soil for remediation: a review

Purpose: Soil contamination mainly from human activities remains a major environmental problem in the contemporary world. Significant work has been undertaken to position biochar as a readily-available material useful for the management of contaminants in various environmental media notably soil. Here, we review the increasing research on the use of biochar in soil for the remediation of some organic and inorganic contaminants.  Materials and methods: Bibliometric analysis was carried out within the past 10 years to determine the increasing trend in research related to biochar in soil for contaminant remediation. Five exemplar contaminants were reviewed in both laboratory and field-based studies. These included two inorganic (i.e., As and Pb) and three organic classes (i.e., sulfamethoxazole, atrazine, and PAHs). The contaminants were selected based on bibliometric data and as representatives of their various contaminant classes. For example, As and Pb are potentially toxic elements (anionic and cationic, respectively), while sulfamethoxazole, atrazine, and PAHs represent antibiotics, herbicides, and hydrocarbons, respectively.  Results and discussion: The interaction between biochar and contaminants in soil is largely driven by biochar precursor material and pyrolysis temperature as well as some characteristics of the contaminants such as octanol-water partition coefficient (KOW) and polarity. The structural and chemical characteristics of biochar in turn determine the major sorption mechanisms and define biochar’s suitability for contaminant sorption. Based on the reviewed literature, a soil treatment plan is suggested to guide the application of biochar in various soil types (paddy soils, brownfield, and mine soils) at different pH levels (4–5.5) and contaminant concentrations ( 50 mg kg−1).  Conclusions: Research on biochar has grown over the years with significant focus on its properties, and how these affect biochar’s ability to immobilize organic and inorganic contaminants in soil. Few of these studies have been field-based. More studies with greater focus on field-based soil remediation are therefore required to fully understand the behavior of biochar under natural circumstances. Other recommendations are made aimed at stimulating future research in areas where significant knowledge gaps exist

The Visual perception of occupants’ on daylight : emphasis on the diversity of luminance ambience due to architecture & effect of glare in office environments

The research investigates the occupant perception of daylight in office buildings in Sri Lanka. Specific focus is drawn to the potential diversity of a luminous ambiance environments, created by daylight and problems associated with glare effect to the visual comfort. The methodology involves an investigationto find the level of occupants‘ perception through a questionnaire survey and analysing the data using the SPSS analytical computer software. In addition, pointed Lux levels in selected areas were measured to find out the activeness of day lighting level using Daylight factor. Simultaneously a photographic survey is used to identify the brighter and darker zones and design intervention of the building designs. According to the data analysis, 97% of responses are found to be less sensitive to day lighting. The results suggest the occupants in investigated office buildings consider daylight as an insignificant component in office environments. Further, it was found that glare; due to extensive difference of lighting level between inside and outside, was an issue to be addressed