The ability of biochar to enhance the physical and hydrological properties of light textured soils is highly dependent on the characteristics of biochar including its particle size. To investigate the effect of biochar particle size on water characteristics and soil structure of a sandy loam soil, date palm biochar prepared at a pyrolysis temperature of 450-500 °C was fractioned by dry sieving into four sizes: 2-1, 1-0.5, 0.5-0.1, and < 0.1 mm, and mixed in soil pots with a sandy loam soil at an application rate of 4%. The soil pots were incubated in a greenhouse for 120 days, and water content was kept at field capacity throughout the experiment. Water retention, hydraulic conductivity, and soil structure parameters were measured. Results showed that the largest increase in both water content at field capacity and available water content was observed with the smallest biochar particle size due to increased microporosity as a result to the larger internal surfaces and the porous structure of the biochar particles. Condense particle packing and increased tortuosity due to increased microporosity resulted in a reduction in saturated hydraulic conductivity and bulk density of the soil and biochar mixtures. Soil structure was improved in the soil and biochar mixtures at all biochar particle sizes, nevertheless, no significant increase in soil structures was observed among biochar particle sizes < 1 mm. The application of biochar with particle sizes < 1 mm can enhance the physical and hydrological properties of light textured soils and increase water conservation in the soil, which will help to reduce the amount of water required for irrigation. However, assessment under field conditions is required to assess the long-term effect of biochar on water characteristics and soil structure.

生物炭增强轻质土壤的物理和水文特性的能力高度取决于生物炭的特性，包括其粒径。为了研究生物炭颗粒尺寸对沙质壤土水分特征和土壤结构的影响，通过干筛将在450-500°C的热解温度下制备的椰枣生物炭分为四个尺寸：2-1、1-0.5 ，0.5-0.1和<0.1 mm，并在砂锅壤土中以4％的施用量混合。将土壤盆在温室中温育120天，并且在整个实验中将水含量保持在田间容量。测量了保水率，水力传导率和土壤结构参数。结果表明，由于微孔增加，由于生物炭颗粒较大的内表面和多孔结构，在田间持水量和可用水含量上都观察到最大的增长，而生物炭颗粒尺寸最小。凝结的颗粒堆积和由于增加的微孔率而导致的曲折性导致土壤和生物炭混合物的饱和水力传导率和堆积密度降低。在所有生物炭粒径下，土壤和生物炭混合物中的土壤结构均得到改善，但是，在<1 mm的生物炭粒径中，未观察到土壤结构的显着增加。粒径<的生物炭的应用 1毫米可以增强轻质土壤的物理和水文特性，并增加土壤中的节水能力，这将有助于减少灌溉所需的水量。但是，需要在野外条件下进行评估，以评估生物炭对水质和土壤结构的长期影响。