行道树作为道路绿化的骨干树种，在美化城市和改善生态环境方面发挥着不可替代的作用，但由于城市环境的复杂性和行道树的生长特点，行道树的安全性面临诸多挑战。为科学评估深圳市深南大道行道树安全性，运用树木视觉诊断法（VTA）、仪器检测法测定深南大道行道树树木外观、树种、主干内部受损率、立地环境和根系生长情况等安全性指标，进行分项评价和整体评估。结果表明：1）行道树主干存在不同程度的空腐，部分树木立地生境较差和根系生长情况不良；2）胸径与内部受损程度、外部受损程度呈极显著正相关（P＜ 0.01），树高与内部受损程度呈极显著正相关（P＜ 0.01），树高与外部受损程度呈显著正相关（P＜ 0.05），冠幅只与外部受损程度呈显著正相关（P＜ 0.05）。最后提出选择适宜树种、定期修剪和修整、加强土壤水分和养分管理、防治病虫害等管护建议，以提高城市防范和抵御树木倒伏、折断等安全风险的能力。

As the backbone tree species of road greening, street trees play an irreplaceable role inbeautifying the city and improving the ecological environment. Due to the complexity ofthe urban environment and the growth characteristics of street trees, the safety of streettrees faces many challenges. In order to scientifically evaluate the safety of street trees onShennan Avenue in Shenzhen, this paper uses Visual Tree Assessment (VTA) and instrumentDetection Method to determine the safety indexes of street trees on Shennan Avenue, suchas tree appearance, species, internal damage rate of trunk, site environment and rootgrowth, and carry out sub-item evaluation and overall evaluation. The results showed thatthe main trunks of the street trees had different degrees of hollow rot, and some of thetrees had poor standing habitats and poor root growth. The diameter at breast height hada highly significant positive correlation with the degree of internal damage and externadamage (P<0.01), tree height had a highly significant positive correlation with the degreeof internal damage (P<0.01) and has a significant positive correlation with the degree ofexternal damage (P<0.05), and crown width only had a significant positive correlation withthe degree of external damage (P<0.05). Finally, this paper proposes management andprotection suggestions such as selecting appropriate tree species, regular pruning andtrimming, strengthening soil moisture and nutrient management, and controlling pests anddiseases, to improve the city's ability to prevent and resist safety risks such as tree fall andbreakage.

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