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Bias in Discontinuous Elevational Transects for Tracking Species Range Shifts
Shixuan Li1, Jiannan Yao1, Yang Lin2,3
1Zhejiang Tiantong Forest Ecosystem National Observation and Research Station, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China.
Plants (Basel, Switzerland)
|January 25, 2025
Summary
Discontinuous elevational transects used to track species range shifts are highly inaccurate. A new study suggests a 50 m quadrat spacing and 60-year interval optimizes monitoring for conservation planning.
Area of Science:
- Ecology
- Conservation Biology
- Climate Change Science
Background:
- Climate change is driving species to migrate towards higher elevations and latitudes.
- Traditional methods using discontinuous elevational transects may introduce significant biases in tracking species movement.
- Inaccurate data on species range shifts can lead to flawed biodiversity conservation policies.
Purpose of the Study:
- To evaluate the accuracy of discontinuous elevational transect methods for monitoring species range shifts.
- To assess the impact of quadrat spacing and survey time intervals on bias in estimating species movement.
- To identify optimal parameters for discontinuous transects to improve conservation planning.
Main Methods:
- Utilized species distribution data from a novel continuous elevational transect.
- Analyzed the effects of varying quadrat spacing and survey time intervals on bias.
- Compared results from discontinuous transects with data from a continuous transect.
Main Results:
- Discontinuous transects failed to detect 7.2% of species and inaccurately estimated shift distances for 78%.
- An overall error rate of 86% was observed with widely used discontinuous transect settings.
- Wider quadrat spacing increased error rates, while longer survey intervals generally reduced them; underestimation of shift distances was consistent.
Conclusions:
- A 50 m quadrat spacing and 60-year survey interval optimize monitoring of species range shifts for conservation.
- Discontinuous transect methods require methodological refinement to accurately inform biodiversity conservation.
- Supplementary, frequent surveys for high-elevation species can enhance accuracy and cost-effectiveness.
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