New paper presents the eLTER Framework of Standard Observations for long-term, integrated environmental monitoring

A new study published in Earth’s Future introduces the eLTER Framework of Standard Observations (eLTER SO) - a structured, harmonized system designed to support consistent long-term environmental observation across Europe. The paper, "Achieving harmonized and integrated long-term environmental observation of essential ecosystem variables - The eLTER Framework of Standard Observations", explains how the eLTER Research Infrastructure (eLTER RI) is improving the comparability and coordination of environmental data across diverse ecosystems and research fields.

The eLTER RI is a pan-European network of long-term research sites focused on observing, analyzing, and modeling environmental and ecosystem change. Its work is guided by the Whole System Approach for in-situ research on Life Supporting Systems (WAILS), which considers interactions among the atmosphere, geosphere, hydrosphere, biosphere, and the anthroposphere. This integrated perspective supports research on how ecosystems function and respond to long-term pressures.

Environmental data are often collected using different methods and at different scales, making it difficult to compare findings across sites or disciplines. The newly proposed eLTER SO aim to address this challenge by defining:

  • Essential ecosystem variables across major system components

  • Harmonized protocols for observing and measuring these variables

  • Cross-sphere observation concepts that link ecological, physical, and socio-ecological processes

By combining scientific requirements with the operational needs of in-situ observatories, the framework supports both academic research and long-term infrastructure management. The authors note that harmonized observations are particularly important for studying gradual or cumulative environmental changes and for supporting interdisciplinary work in Earth system and sustainability science.

“The Standard Observations provide a common foundation for the work carried out across the eLTER infrastructure”, said Dr. Steffen Zacharias, researcher at the Helmholtz Centre for Environmental Research (UFZ) and a leading contributor to the eLTER. “By agreeing on shared variables and methods, we enable comparisons across sites and countries, and we improve our ability to understand long-term environmental trends. This framework strengthens collaboration and helps ensure that the data collected today will remain valuable for future research.”

The development of the eLTER SO builds on many years of collaboration among European long-term ecological research networks. While these networks have contributed valuable data, their observation approaches historically varied in scope, frequency, and methodology. As the need for coordinated, interoperable data grew—particularly in the context of climate change, land-use transitions, and biodiversity loss—scientists and infrastructure operators began working toward a more unified system.

This process advanced within the eLTER community through workshops, expert consultations, and alignment with international Essential Variable frameworks. The introduction of the WAILS concept helped connect observations across different spheres of the Earth system. Over time, these efforts produced a shared set of variables and protocols that reflect both scientific priorities and the practical considerations of long-term field sites. The resulting eLTER SO framework now serves as a reference for consistent environmental monitoring across the eLTER network and beyond.

The eLTER Standard Observations are designed to facilitate research that is:

  • Integrative, combining insights from multiple disciplines

  • Place-based, respecting local environmental characteristics

  • Long-term, supporting observations over decades

  • Cross-scale, linking local measurements to broader regional and global processes

By providing common standards, the framework improves data interoperability and supports collaboration across the environmental research community. It offers a foundation for future work in areas such as ecosystem modeling, sustainability assessments, and evidence-based environmental policy.

Link to publication: https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2025EF006743

Cite as:
Zacharias, S., Lumpi, T., Weldon, J., Dirnböck, T., Gaillardet, J., Haase, P., et al. (2026). Achieving harmonized and integrated long-term environmental observation of essential ecosystem variables - The eLTER framework of standard observations. Earth's Future, 14, e2025EF006743. https://doi.org/10.1029/2025EF006743



Read the feature interview with Dr. Steffen Zacharias - eLTER will be a flagship for the European commitment to a progressive Global Environmental Policy

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