Optical contact angle of air-dry soil samples

The optical contact angle of the samples was measured by attaching a one-grain layer of the air-dry soil sample to a piece op tape and release a drop of water onto it. The contact angle was determined from the image of the water drop on the soil (see supplementary pictures). The soil samples were taken from cover crop root channels and bulk soil six weeks after the cover crops had been terminated with a herbicide. Research domain: Soil Sciences Research question: How hydrophobic is the material in cover crop root channels.

本研究通过将风干土壤样品铺成单颗粒层并粘贴至胶带表面，随后向其滴加一滴水，以此测定样品的光学接触角。接触角依据土壤表面水滴的图像确定（详见补充图片）。土壤样品采集自使用除草剂灭杀覆盖作物六周后的覆盖作物根通道与原状土壤。研究领域：土壤科学。研究问题：覆盖作物根通道内的物质疏水性如何？