title: Feasibility of biochar application on a landfill final cover-a review on balancing ecology and shallow slope stability.
abstract: Due to the increasing concerns on global warming, scarce land for agriculture, and contamination impacts on human health, biochar application is being considered as one of the possible measures for carbon sequestration, promoting higher crop yield and contamination remediation. Significant amount of researches focusing on these three aspects have been conducted during recent years. Biochar as a soil amendment is effective in promoting plant performance and sustainability, by enhancing nutrient bioavailability, contaminants immobilization, and microbial activities. The features of biochar in changing soil physical and biochemical properties are essential in affecting the sustainability of an ecosystem. Most studies showed positive results and considered biochar application as an effective and promising measure for above-mentioned interests. Bio-engineered man-made filled slope and landfill slope increasingly draw the attention of geologists and geotechnical engineers. With increasing number of filled slopes, sustainability, low maintenance, and stability are the major concerns. Biochar as a soil amendment changes the key factors and parameters in ecology (plant development, soil microbial community, nutrient/contaminant cycling, etc.) and slope engineering (soil weight, internal friction angle and cohesion, etc.). This paper reviews the studies on the production, physical and biochemical properties of biochar and suggests the potential areas requiring study in balancing ecology and man-made filled slope and landfill cover engineering. Biochar-amended soil should be considered as a new type of soil in terms of soil mechanics. Biochar performance depends on soil and biochar type which imposes challenges to generalize the research outcomes. Aging process and ecotoxicity studies of biochar are strongly required.
authors.affiliation: Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China.
authors.forename: Xun-Wen
authors.initials: XW
authors.lastname: Chen
authors.affiliation: Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China.
authors.forename: James Tsz-Fung
authors.initials: JT
authors.lastname: Wong
authors.affiliation: Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China. cecwwng@ust.hk.
authors.forename: Charles Wang-Wai
authors.initials: CW
authors.lastname: Ng
authors.affiliation: Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China. minghwong@ied.edu.hk.|Consortium on Health, Environment, Education and Research (CHEER), Department of Science and Environmental Studies, The Hong Kong Institute of Education, Office B3-2/F-33, Tai Po, Hong Kong SAR, China. minghwong@ied.edu.hk.|Croucher Institute for Environmental Sciences, and Department of Biology, Hong Kong Baptist University, Kowloon Tong, Hong Kong SAR, China. minghwong@ied.edu.hk.
authors.forename: Ming-Hung
authors.initials: MH
authors.lastname: Wong
mesh_terms: D000818:Animals; D057965:Carbon Sequestration; D002606:Charcoal / Q000737:chemistry*; D005240:Feasibility Studies; D057232:Global Warming; D006801:Humans; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis; D012987:Soil / Q000737:chemistry; D012989:Soil Pollutants / Q000032:analysis; D064091:Waste Disposal Facilities
chemical_list: D011084:Polycyclic Aromatic Hydrocarbons; D012987:Soil; D012989:Soil Pollutants; C540010:biochar; D002606:Charcoal
keywords: Bio-resource; Ecosystem restoration; Nutrient cycle; Slope engineering; Soil mechanics; Terrestrial ecology