Automating lichen monitoring in ecological studies using instance segmentation of time-lapse images

Safwen Naimi; Olfa Koubaa; Wassim Bouachir; Guillaume-Alexandre Bilodeau; Gregory Jeddore; Patricia Baines; David Correia; Andre Arsenault

arXiv · 2310.17080

Automating lichen monitoring in ecological studies using instance segmentation of time-lapse images

Safwen Naimi·Olfa Koubaa·Wassim Bouachir·Guillaume-Alexandre Bilodeau·Gregory Jeddore·Patricia Baines·David Correia·Andre Arsenault

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Abstract

Lichens are symbiotic organisms composed of fungi, algae, and/or cyanobacteria that thrive in a variety of environments. They play important roles in carbon and nitrogen cycling, and contribute directly and indirectly to biodiversity. Ecologists typically monitor lichens by using them as indicators to assess air quality and habitat conditions. In particular, epiphytic lichens, which live on trees, are key markers of air quality and environmental health. A new method of monitoring epiphytic lichens involves using time-lapse cameras to gather images of lichen populations. These cameras are used by ecologists in Newfoundland and Labrador to subsequently analyze and manually segment the images to determine lichen thalli condition and change. These methods are time-consuming and susceptible to observer bias. In this work, we aim to automate the monitoring of lichens over extended periods and to estimate their biomass and condition to facilitate the task of ecologists. To accomplish this, our proposed framework uses semantic segmentation with an effective training approach to automate monitoring and biomass estimation of epiphytic lichens on time-lapse images. We show that our method has the potential to significantly improve the accuracy and efficiency of lichen population monitoring, making it a valuable tool for forest ecologists and environmental scientists to evaluate the impact of climate change on Canada's forests. To the best of our knowledge, this is the first time that such an approach has been used to assist ecologists in monitoring and analyzing epiphytic lichens.

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BibTeX RIS

Safwen Naimi, Olfa Koubaa, Wassim Bouachir, Guillaume-Alexandre Bilodeau, Gregory Jeddore, Patricia Baines, David Correia, Andre Arsenault. 2023-10-26. Automating lichen monitoring in ecological studies using instance segmentation of time-lapse images. https://arxiv.org/abs/2310.17080

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