Genesis, goals and achievements of Long-Term Ecological Research at the global scale: A critical review of ILTER and future directions

Since its founding in 1993 the International Long-term Ecological Research Network (ILTER) has gone through pronounced development phases. The current network comprises 44 active member LTER networks representing 700 LTER Sites and similar to 80 LTSER Platforms across all continents, active in the fields of ecosystem, critical zone and socio-ecological research. The critical challenges and most important achievements of the initial phase have now become state-of-the-art in networking for excellent science. At the same time increasing integration, accelerating technology, networking of resources and a strong pull for more socially relevant scientific information have beenmodifying themission and goals of ILTER. This article provides a critical review of ILTER's mission, goals, development and impacts. Major characteristics, tools, services, partnerships and selected examples of relative strengths relevant for advancing ILTER are presented. We elaborate on the tradeoffs between the needs of the scientific community and stakeholder expectations. The embedding of ILTER in an increasingly collaborative landscape of global environmental observation and ecological research networks and infrastructures is also reflected by developments of pioneering regional and national LTER networks such as SAEONin South Africa, CERN/CEOBEX in China, TERN in Australia or eLTER RI in Europe. The primary role of ILTER is currently seen as a mechanismto investigate ecosystemstructure, function, and services in response to awide range of environmental forcings using long-term, place-based research. Wesuggest fourmain fields of activities and advancements for the next decade through development/delivery of a: (1) Globalmulti-disciplinary community of researchers and research institutes; (2) Strategic global framework and strong partnerships in ecosystem observation and research; (3) Global Research Infrastructure (GRI); and (4) a scientific knowledge factory for societally relevant information on sustainable use of natural resources. (c) 2018 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license.