A LoRaWAN-based environmental sensing network for urban green space monitoring with demonstrated application for stormwater management

Monitoring urban green spaces (UGSs) is crucial for achieving sustainable urban development and ecological resilience. Leveraging LoRaWAN technology, a wireless environmental sensing system was developed and implemented to monitor soil moisture dynamics across seven diverse UGSs over a year. Analyses revealed notable variations in soil moisture influenced by vegetation types, soil conditions and physical settings. Seasonal trends indicated lower summer soil moisture in some UGSs resulting from increased evapotranspiration, while others maintained higher soil moisture due to more frequent irrigation. The soil moisture response to rainfall was quantitatively modeled, demonstrating the increase in soil moisture is highly positively dependent on rainfall amount and negatively dependent on initial moisture level. Both factors were significant (p<0.001) in most cases, and the models’ adjusted R² values were all above 0.65 except for one node. The findings also unveiled more dynamic ranges of UGS runoff coefficients than government guideline values, especially high runoff coefficients (0.4 to 1.0) for rainfall events above 50 mm. Therefore, although existing UGSs can help absorb smaller storms, proactive drainage systems are needed for UGSs to handle extreme events. The study highlights LoRaWAN's efficacy in urban environmental monitoring and provides valuable insights for managing and optimizing UGSs, especially in stormwater management.