Forest monitoring sites network

The developed RemoTrees device prototypes will be tested under field conditions at a number of preselected forest sites, categorized in "Level 1", easier to reach and with good infrastructure and "Level 2" which are hard-to-reach, located in boreal/high altitude, dry and wet tropical zones, where the performance and reliability of prototypes under really extreme environmental conditions will be evaluated.

At Level 1 sites, data collected from Remotrees system (Beta prototype) will be quality assessed against a benchmark based on available high-end instrumentation and state of the art techniques. Quality assessment will include satellite communication and energy harvesting systems. The necessary system improvements will be implemented in a new gamma prototype for installation at Level 2 sites, the data of which will undergo a final scrutiny for system performance and calibration stability.

Identification and collection of site metadata and of ancillary data relative to the field sites (e.g., location, vegetation type, climatic features, soil type, etc.) and to the monitored trees (e.g., stem diameter, height, health status, etc.) will be prepared as well as the definition of installation protocols and field experimental designs.

1. DEMMIN Test Site (Germany)

The DEMMIN (Durable Environmental Multidisciplinary Monitoring Information Network) test site, represents a comprehensive facility in Mecklenburg-Western Pomerania, northern Germany. DEMMIN spans heterogeneous landscapes including agricultural areas and forest components. In 2011, GFZ established a crane facility in the urban forest of DEMMIN as a contribution to the TERENO initiative to acquire hyperspectral measurements. The site's forest areas provide critical validation data for hyperspectral forest classification algorithms and support canopy-level measurements. DEMMIN contributes to long-term ecosystem monitoring across the temperate European forest-agriculture landscape mosaic. 

2. Marburg Open Forest (Germany)

The Marburg Open Forest (MOF) constitutes a 244-hectare research and educational forest facility operated by Philipps-Universität Marburg. The forest extends across elevational gradients from 212 m a.s.l. to 488 m a.s.l. in the Lahn Valley, with the majority of forest stands situated within the subcontinental beech mixed forest zone. Fagus sylvatica dominates the species composition, complemented by approximately 30% Quercus petraea coverage. MOF serves as an innovative teaching and research forest, integrated into the curricula of degree programs such as Physical Geography and Biodiversity and Nature Conservation. The MOF supports diverse research projects in areas such as forest ecology, biodiversity monitoring, and climate adaptation through state-of-the-art infrastructure. The facility maintains comprehensive monitoring infrastructure including climatological, hydrological, and tree physiological sensor networks. 

3. Cembra Valley (Italy)

The Cembra site is an alpine mixed forest (1250 m a.s.l) in the Trentino province. The European beech dominates the stand composition, which includes a limited presence of Norway spruce, and a minor presence of silver fir, silver birch, Scots pine, European larch and rowan. The stand grows on an acidic brown earth soil, over a porphyry bedrock. Since 2017, the site has been subject to experimental nitrogen fertilization treatments, with fertilization delivered both above-canopy and below-canopy to circular plots. The ecological monitoring of beech trees has been since then carried out by means of clusters of traditional and Internet of Things based devices recording trees radial growth, sap flow density and characterizing the forest microclimatic space. The stand is part of AnaEE project.

4. Majadas del Tietar (Spain)

The Majadas del Tietar research site is situated within a Mediterranean dehesa ecosystem in Cáceres, Extremadura (260 m a.s.l.), representing a traditional oak savanna landscape characterized by low-density Quercus ilex subsp. ballota stands (24.8 trees ha⁻¹, 19.8% canopy cover). The site experiences a continental Mediterranean climate with mean annual temperature of 17.2°C and precipitation of 670 mm, exhibiting pronounced summer drought conditions. Since 2014, the site has served as a focal point for the MANIP (Manipulation of Nitrogen and Phosphorus) experiment, incorporating multiple eddy covariance towers, sub-canopy flux measurements, and extensive ground-based instrumentation to investigate ecosystem responses to nutrient manipulation and water availability gradients.

5. San Francisco (Ecuador)

The Estatión Cientìfica San Francisco is located in the Reserva Biológica San Francisco on the Cordillera Real, an eastern range of the South Ecuadorian Andes. The core research area of around 11 km² stretches on the north-facing slopes of the valley from ~1800 m at the valley bottom to the mountain crest at ~3200 m altitude.  The reserve encompasses primary tropical mountain rainforest characterized by evergreen vegetation and exceptionally high species diversity. The elevational gradient creates distinct ecological zones, with cloud forest formations dominating the mid-elevation ranges. The site experiences a tropical mountain climate with pronounced seasonality in precipitation patterns, despite the evergreen nature of the forest canopy. Research infrastructure supports comprehensive ecological monitoring programs including biodiversity inventories, forest dynamics studies, and climate-ecosystem interaction research. Based on the scientific results, the entire area has been awarded the rank of a UNESCO Biosphere reserve.

During the first 18 months of the project, Phillips-Universität Marburg (UMR) led the preparation of protocols for site metadata collection, and the development of the experimental design for device deployment at Level 1 sites. 

Site Metadata Generation (to be collected in situ)

Field metadata requirements were identified and standardized collection protocols were established. Each site will be comprehensively characterized through descriptive documentation that includes forest composition and structure, tree size distribution, age composition, and current and historical management practices. This documentation will be supplemented with plot photographs and aerial imagery where feasible (such as drone-mounted cameras). All selected Level 1 study sites are already well-documented, and existing characterization materials will be compiled.

During summer 2025, each Level 1 site will undergo drone-mounted LIDAR surveys to derive canopy height measurements and perform single-tree canopy segmentation. Additionally, detailed metrics will be recorded for all trees designated for RemoTrees Trunk (RT-T) sensor installation, including GPS coordinates, diameter, height, species identification, and hemispherical photography. The metadata collection protocols are based on established standards and guidelines.

Protocols for device installation

A set of predefined installation procedures to optimise the devices functionality was provided, based on the experience of the consortium members with previous versions of the devices. The installation guidelines included a list of required tools, device placement on the stem and correct sensor installation practice.

Cross-WP Collaboration

• Supported WP7 deliverables with metadata workflows and Individual Tree Structural Metrics documentation

• Contributed to global data management strategy implementation

Data Access and FAIR Compliance

All workflows are publicly available through:

• Repository: DataPlant Git

• Archive: Zenodo DOI 10.5281/zenodo.15635129

The repository includes two fully documented, reproducible workflows:

• Standardized geospatial metadata generation pipeline

• Spatial model for tree-level structural metrics and sensor placement optimization

Quality Assurance

• Internal monitoring through Git version control and milestone tracking

• Metadata validation routines implemented

• Compliance with ISO and INSPIRE international standards

• Consortium review completed with no significant deviations

Impact and Next Steps

Tools developed in WP2 have enhanced the project's capacity for scalable, interoperable solutions. Workflows are currently being deployed in field campaigns and will support expansion to Level 2 sites. External expert evaluation scheduled for future reporting periods.