景观环境常用有机地表覆盖物的吸水性能研究

有机地表覆盖物具有滞留雨水、降低地表径流的作用。为优选适用于城市雨水管理的有机地表覆盖物，选择16种景观环境常用有机地表覆盖物材料，对其材料密度、质量吸水倍率、质量吸水速率、体积吸水倍率、体积吸水速率和饱和时长进行了测定。结果表明：1)质量吸水倍率：锯末和花生壳表现最好，蚯蚓粪表现最差；2)质量吸水速率：各材料0~10min内的质量吸水速率均为最高，而后下降较快，第10min时，16种材料的质量吸水率占比平均为75.60%，最低的核桃壳为51.22%，最高的复叶槭粉碎物达89.42%；3)体积吸水倍率：锯末、蚯蚓粪、花生壳和柳树皮的体积吸水倍率表现较好，松针和打磨松树皮(3~5cm)表现较差；4)体积吸水速率：各材料0~10min内的体积吸水速率规律与质量吸水速率一致，打磨松树皮(3~5cm)、松针和核桃壳的体积吸水速率较小，最高的锯末是打磨松树皮(3~5cm)的8.83倍；5)饱和时长：花生壳用时最短，25min就达到饱和状态，松塔壳用时最长，为60min。研究结果可为城市地面及屋顶绿化所需有机地表覆盖物的优选提供参考依据。

Study on Water Absorbency of Organic Mulch Used in Landscape Environment

Organic mulch has the function of retaining rainwater and reducing surface runoff. In order to select organic mulches suitable for urban rainwater management, this study selected 16 kinds of common organic mulch materials, and the material density, mass absorbent rate, mass absorbent speed, volume absorbent rate, volume absorbent speed and saturation time were measured. The results showed that: 1) According to the mass absorbent rate, sawdust and peanut shells performed best, and earthworm dung performed worst; 2) Mass absorption speed: The mass absorption rate of each material in 0-10min is the highest, and then the decline is faster. At the time of 10min, the total mass absorbent ratio of 16 kinds of materials accounted for an average of 75.6%, the lowest walnut shell was 51.22%, and the highest compound leafhopper was 89.42%; 3) Volume absorbent rate: The volume absorbent rate of sawdust, earthworm dung, peanut shell and willow bark performed better, and the performance of pine needles and polished pine skin (3-5cm) was poor; 4) According to the volume absorption speed: the volume absorption rate in each material 0-10min is the same as the mass absorption rate, and the volume absorption rate of pine bark (3-5cm), pine needles and walnut shells is minimized. The highest sawdust is 8.83 times that of polished pine bark (3-5cm); 5) Saturation time: The shortest time for peanut shells is 25 minutes, and the longest time for pine shell is 60 minutes. This study can provide a reference for the optimization of organic mulch materials required for urban ground and roof greening.