Biochar and Water Quality

Area of Science:

• Environmental Science
• Soil Science
• Water Quality Management

Background:

• Biochar application is an emerging strategy for enhancing soil ecosystem services.
• The impact of biochar on water quality parameters remains under-explored.
• This review synthesizes current research on biochar's effects on water pollution.

Purpose of the Study:

• To review and synthesize existing literature on biochar's impact on water quality.
• To assess biochar's effectiveness in reducing water erosion, nitrate leaching, and other pollutants.
• To identify factors influencing biochar's efficacy and highlight knowledge gaps.

Main Methods:

• Systematic literature review of studies on biochar and water quality.
• Analysis of reported data on runoff, soil loss, and nutrient/pesticide leaching.
• Synthesis of findings regarding influencing factors and potential concerns.

Main Results:

• Biochar generally reduces runoff (5-50%) and soil loss (11-78%), with co-application enhancing effects.
• Nitrate leaching is reduced (2-88%), while phosphate and dissolved carbon leaching show mixed results.
• Biochar filters urban runoff, adsorbs pollutants, and reduces pesticide losses, but impacts vary.

Conclusions:

• Biochar shows potential for improving water quality by reducing erosion and pollutant losses.
• Factors like feedstock, pyrolysis, application method, and amendments significantly influence outcomes.
• Further field-scale research is crucial to fully understand biochar's water quality benefits and limitations.