Three-year field study on grass growth and soil hydrological properties in biochar-amended soil  

作　　者：Haowen Guo Charles Wang Wai Ng Junjun Ni Qi Zhang Yuchen Wang 

机构地区：[1]Department of Civil and Environmental Engineering,The Hong Kong University of Science and Technology,Hong Kong,China [2]School of Transportation,Southeast University,Nanjing,China

出　　处：《Journal of Rock Mechanics and Geotechnical Engineering》2024年第7期2764-2774,共11页岩石力学与岩土工程学报（英文版）

基　　金：the financial sponsorship from the National Natural Science Foundation of China(Grant Nos.U20A20320,52308342);the Fundamental Research Funds for the Central Universities(Grant No.RF1028623071).

摘　　要：Field monitoring was conducted to investigate and quantify the long-term effects of peanut shell biochar on soil-grass interaction over three years.Three 10 m5 m grassed plots were constructed in completely decomposed granitic soil.Two of them were amended,respectively,with 5%and 10%biochar contents(m^(3)/m^(3))for grass growth,while the third was without biochar amendment.During the threeyear monitoring,plant characteristics,saturated water permeability(k_(s))of grassed soil and soil suction were measured.The monitored results show that the grass leaf area index(LAI)and root length density(RLD)with biochar amendment were improved by 38%and 200%,respectively.In the grassed plot without biochar,a threshold RLD existed with a value of 1.7 cm/cm^(3),beyond which k_(s) raised pronouncedly.The threshold RLD increased by 52%when biochar content increased from 0%to 10%.This implies that biochar may restrict the increase in k_(s) of grassed soil due to the rise in the threshold RLD.The presence of biochar and grass can retain over 100%higher suction after heavy rainfalls,while 54%lower peak suction under evapotranspiration(ET)compared with the non-amended plot.Biochar can alleviate the negative effects on hydraulic properties caused by plant growth and reduce ET-induced excessive water loss.A 5%peanut shell biochar content is recommended for the long-term management of vegetated earthen infrastructures.

关 键 词：Soil-grass interaction BIOCHAR LONG-TERM Water infiltration Soil drying 

分 类 号：TU473.1[建筑科学—结构工程]