玉米秸秆生物炭对贵州黄壤持水能力的影响

生物炭具有丰富的微孔结构,能够影响土壤的持水性能,对植物生长和土壤中养分的保持有着重要意义。而土壤水分特征曲线又是表征土壤持水能力的一个重要指标。本文通过压力膜法测定添加不同比例生物炭的黄壤水分特征曲线,并结合van Genuchten模型对实测结果进行拟合,推导水动力学参数。结果表明,随着生物炭施入量的增加(0、5%、10%),土壤的田间持水量增加,凋萎含水量降低,土壤有效含水量增加。生物炭添加能够显著提高土壤的持水能力,增强水分的可利用性。同时,van Genuchten模型拟合结果同实测值高度相似,可以用作预测生物炭改良土壤的水动力学参数。

Impact of Corn Straw Biochar on Water Holding Capacity of the Yellow Soil in Guizhou Province, China

Owing toits porous structure, biochar amendment in the soil is expected to increase soil water holding capacity and is important for plant growth and nutrition reservation. Soil water retention curve depicts soil water holding capacity. Here we studied the effect of biochar on water retention curve of the yellow soil from Guizhou Province at the application rates 0, 5% and 10%, corresponding to non-biochar, 50t/ha and 100t/ha of biochar, respectively, by using pressure membrane analyzer. And van Genuchten model was used to simulate the observed data to deduce hydrodynamic parameters. We found that biochar amendment increased the field capacity and effective water content but reduced the permanent wilting point, as results, improving the water holding capacity and water availability of the soil. The change of water retention curve abides by the van Genuchten model at the various application rate of Biochar, indicating that the retention curve can be predicted by the model.