Xu Yaowen, Jiao Jiejie
Zhejiang Academy of Forestry, Hangzhou, China.
Zhejiang Hangzhou Urban Ecosystem Research Station, Hangzhou, China.
Front Public Health. 2025 Jun 17;13:1597966. doi: 10.3389/fpubh.2025.1597966. eCollection 2025.
Negative air ions (NAIs) are recognized as critical indicators of air quality and environmental well-being, with urban green spaces serving as vital sources of these beneficial ions. However, the spatiotemporal dynamics of NAIs across heterogeneous urban green infrastructure and their environmental determinants remain understudied. In this study, we examined the spatial and temporal distribution of negative air ions concentrations within various urban green spaces, specifically suburban forests, parks, roadside greenery, and community green spaces. A stratified sampling design was implemented across 240 georeferenced sites. At each site, NAIs concentrations were quantified using a three-phase measurement protocol:morning (8:00-9:30), midday (12:30-14:00) and evening (17:00-18:30). Field campaigns were conducted during the summer months (June to August) of 2024. Suburban forest areas showed significantly ( < 0.05) elevated NAIs levels compared to park, roadside greenery, and community green spaces, while roadside greenery displayed the lowest NAIs levels. We found that environmental factors, including relative humidity, temperature, air pressure, and particulate matter (PM) concentration, significantly influence NAIs concentrations. Notably, relative humidity and temperature demonstrated a positive impact on NAIs levels, whereas air pressure and PM concentration showed a negative influence. These findings suggest that vegetation type, microclimatic conditions, and air quality have a crucial role in regulating NAIs generation and distribution. The study provides valuable insights for urban green space planning and management to enhance air quality and promote public health through optimized green infrastructure design.
负氧离子被视为空气质量和环境福祉的关键指标，城市绿地是这些有益离子的重要来源。然而，负氧离子在异质城市绿色基础设施中的时空动态及其环境决定因素仍未得到充分研究。在本研究中，我们考察了各类城市绿地（具体为郊区森林、公园、路边绿化和社区绿地）中负氧离子浓度的时空分布。在240个地理参考地点实施了分层抽样设计。在每个地点，采用三相测量方案对负氧离子浓度进行量化：早晨（8:00 - 9:30）、中午（12:30 - 14:00）和晚上（17:00 - 18:30）。于2024年夏季（6月至8月）开展了实地调查。与公园、路边绿化和社区绿地相比，郊区森林地区的负氧离子水平显著升高（ < 0.05），而路边绿化的负氧离子水平最低。我们发现，包括相对湿度、温度、气压和颗粒物（PM）浓度在内的环境因素对负氧离子浓度有显著影响。值得注意的是，相对湿度和温度对负氧离子水平有积极影响，而气压和PM浓度则有负面影响。这些发现表明，植被类型、微气候条件和空气质量在调节负氧离子的产生和分布方面起着关键作用。该研究为城市绿地规划和管理提供了有价值的见解，以便通过优化绿色基础设施设计来改善空气质量和促进公众健康。
