How long do population level field experiments need to be? Utilising data from the 40-year-old LTER network
Sarah Cusser1,2, Jackson Helms1,3, Christie A Bahlai1,4
1W.K. Kellogg Biological Station, Department of Integrative Biology, Michigan State University, Hickory Corners, MI, USA.
Ecology Letters
|February 22, 2021
Summary
Long-term ecological research (LTER) studies in dynamic environments or on plants require more time to yield consistent results. Multi-decadal experiments are crucial for understanding ecological trends.
Area of Science:
- Ecological research
- Environmental science
- Long-term ecological studies
Background:
- The Long-Term Ecological Research (LTER) network provides extensive data spanning 40 years.
- Understanding the time required for ecological studies to achieve consistent results is vital for data interpretation.
Purpose of the Study:
- To investigate how environmental factors and taxa influence the duration needed for ecological research to yield consistent findings.
- To assess the consistency of results in long-term ecological experiments.
Main Methods:
- Analysis of long-term (over 10 years) press experiments from the LTER network focusing on organismal abundance.
- Application of a moving-window algorithm to determine the time to consistent results.
Main Results:
- Studies in dynamic abiotic environments require longer research durations for consistent results compared to stable environments.
- Plant studies were more prone to spurious results than animal studies.
- Nearly 50% of the investigated studies needed 10 years or more to reach consistency; 4% required over 20 years.
Conclusions:
- Environmental dynamism and study taxa significantly impact the time needed for ecological research consistency.
- The findings underscore the critical importance of long-term data and multi-decadal experiments for robust ecological understanding and prediction.
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