The detected effects of driptips and leaf wettability on the kinetic energy of throughfall in rubber‐based agroforestry in Xishuangbanna

Driptips play important roles in controlling soil erosion and in the water cycle. The driptips size distribution and the morphology of water droplets on the leaves among rubber (Hevea brasiliensis) and intercropping species (Camellia sinensis, Citrus reticulata, Flemingia macrophylla and Theobroma cacao) were measured. Driptip‐producing experiments were conducted indoors on stabilized leaves of five species with artificially mist spray. In all five foliage species, the diameter of the driptips from rubber leaves was the lowest. Furthermore, the relationship between driptips size and the mean leaf width at 3 mm from the rubber leaf tip was significantly positively correlated. Leaf wettability as measured by water droplets height linearly increase with the total volume of water which dropped on the leaves of all five species. The contact angle of the water droplets and the total volume of the droplet were significantly negatively correlated. Based on physical theory, the kinetic energy of the driptips was calculated by estimating the diameters of the driptip from all five species. The results indicated that it was important to consider the kinetic energy of driptips in selection of intercropping species when constructing rubber‐based agroforestry plantations. Understanding the relationship between driptips size and the development of leaf tips (leaf width at 3 mm from the leaf tip) will require more experiments with different leaf inclinations, and the results also confirmed that using the contact angle of water droplets to assess leaf wettability. This study can help to predict canopy water processes, such as canopy water storage and drainage.