Effects of biochar application on phreatic water evaporation and water-salt distribution in coastal saline soil

Abstract

A 35-day simulated evaporation experiment was conducted to evaluate the effects of biochar application on phreatic water evaporation and water-salt distribution in coastal saline soil. Three biochar rates (0, 1%, and 5%; w/w) were applied to 65-cm-long soil columns. Results showed that applying the low biochar application rate effectively inhibited soil water evaporation. The 1% biochar treatment resulted in 4.4% lower cumulative soil water evaporation compared with the control, while it caused salt accumulation in the surface soil. By contrast, the high biochar application rate had little effect on cumulative soil water evaporation. Nonetheless, the 5% biochar treatment significantly increased the soil water-holding capacity while decreasing sodium adsorption ratio and salinity in the surface soil. In conclusion, applying a higher biochar rate (e.g., 5%) could improve salt water-distribution in the coastal saline soil under the experimental conditions.

Keywords:

• application rate
• maize biochar
• saline soil
• salt accumulation
• water evaporation
• water migration

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This research was supported by the National Key Research and Development Program of China (2016YFC0400202), and the National Natural Science Foundation of China (41501309 and 41771256).