摘要
该文选取2种粒径（细炭0.013-0.048 mm、粗炭0.3-0.7 mm）的生物炭,以2种质量百分比（3%、6%）施入一种粉黏壤土,通过测定不同粒径生物炭及施加比例下土壤的水分特征曲线、饱和水力传导度、收缩性及饱和膨胀率,研究生物炭对粉黏壤土水力参数及胀缩性的影响。结果表明,2种粒径及添加比例的生物炭均降低了粉黏壤土的持水能力。但4种添加生物炭处理相互之间持水能力差异不显著。生物炭可降低粉黏壤土中极微孔隙和中大孔隙的比例,提高微孔隙和小孔隙所占的比例。生物炭的添加降低了该粉黏壤土的饱和含水率和凋萎系数。细炭对粉黏壤土的田间持水率没有显著影响,粗炭降低了粉黏壤土的田间持水率。两种粒径的生物炭均可提高粉黏壤土的有效含水率,并降低离心失水过程中土壤的收缩,在这2方面细炭的影响效果比粗炭显著;细炭的添加对粉黏壤土饱和膨胀率没有显著影响,粗炭则降低了粉黏壤土的饱和膨胀率。2种粒径生物炭的添加均降低了该粉黏壤土的饱和水力传导度。3%和6%的添加比例在大部分研究指标中未表现出明显差异。该研究可为生物炭在土壤环境修复应用方面提供一定的理论指导。
Biochar is an effective soil amendment. Its effects on soil chemical properties have been widely studied but little is known about its influence on soil hydraulic properties. In this study, we aimed to investigate sizes and addition proportion of biochar on silty clay loam. The loam was collected from 0-10 cm paddy field in Qujialing research base of State Key Laboratory of Water Resources and Hydropower Engineering Science（ which located on Jingzhou City, Hubei province）. Two kinds of biochar sizes were designed including fine biochar with size of 0.013-0.048 mm and coarse biochar with size of 0.3-0.7 mm. They were added to loam in two ratios of 3% and 6%, respectively. The hydraulic parameters and shrinkage-swelling rate of silty clay loam were determined. The centrifugal method was used to measure soil water characteristic curves, and vernier caliper was used to measure shrinkage properties in the process of the centrifugation. Results showed that： 1） Both fine and coarse biochar addition could decrease water retention ability of tested soil, but the effects of biochar sizes and addition ratios were not significantly different; Biochar addition increased the proportion of very fine（〈0.3 μm） and middle-large（〉30 μm） pores in total pores, but increased that of minor and small pores（≥0.3-30 μm）; Fine biochar addition could enhance development of pores ≥0.3-5 μm while coarse biochar addition facilitated pore development of ≥5-30 μm; In general, addition ratios did not significantly affect pore distribution; 2） Biochar application decreased the saturated moisture content and wilting coefficient of tested soil but increased effective moisture content in soil; Fine biochar had the highest capacity to increase soil effective moisture, and the effects were not affected by biochar addition ratios; Soil water holding capacity was greatly affected by coarse biochar addition but not by fine biochar addition, and coarse biochar could decrease water holding capacity; 3） Both fine and co
出处
《农业工程学报》
EI
CAS
CSCD
北大核心
2015年第17期136-143,共8页
Transactions of the Chinese Society of Agricultural Engineering
基金
国家科技支撑计划(2015BAD05B02)
国家自然科学基金(51109166)
中央高校基本科研业务费专项资金(2042014kf0280)
关键词
土壤
胀
缩
生物炭
粉黏壤土
水分特征曲线
饱和水力传导度
soils
swelling
shrinkage
biochar
silty clay
water characteristic curves
saturated hydraulic conductivity
