Validation of a Low-Cost MEMS Inclinometer for Static Tree Stability Monitoring

Urban trees and forests provide essential ecosystem services, including carbon sequestration and climate regulation, but their capacity to deliver these benefits can be compromised by increasing disturbances associated with climate change. Tree stability assessment is therefore a key component of adaptive forest and urban green infrastructure management. Visual Tree Assessment (VTA) is typically the first step in risk analysis and is sometimes complemented by instrumental methods such as dynamic and static tests. Static pulling tests provide quantitative information on anchorage and mechanical stability, but their cost and logistical complexity generally limit their application to site-specific investigations.

This study, carried out within the TREESURE project, evaluates the performance of a low-cost Micro-Electro-Mechanical Systems (MEMS) inclinometer for static tree tilt monitoring, with the aim of assessing its suitability for wider and longer-term deployments in support of resilience-oriented tree management. The approach combines a laboratory calibration against a geometric reference with field comparisons against a professional high-precision inclinometer commonly used in static pulling tests. In the laboratory, using a calibrated tilting beam and a 120 s averaging window, the MEMS sensor exhibited absolute errors on the order of a few hundredths of a degree, with maximum deviations of approximately 0.015°. In field conditions, comparisons were performed in the relative domain (baseline defined on the first stable plateau) along the longitudinal component, showing high concordance with the reference inclinometer.

The results demonstrate that low-cost MEMS inclinometers can provide reliable measurements for static tree tilt monitoring. Owing to their battery-powered wireless operation and simplified data processing, such sensors offer potential for scalable and continuous monitoring of tree stability. This capability may support proactive management strategies aimed at reducing storm-related tree failures, enhancing tree longevity, and indirectly contributing to the preservation of forest and urban tree carbon stocks under increasing climate-induced disturbance regimes.