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Title: Explaining Patterns of Biodiversity Across Neon Sites Using Landsat-Based Disturbance Metrics
Disturbance regimes can strongly influence geographic patterns of biodiversity. The types of disturbances and their frequencies can have varying impacts on different dimensions of biodiversity and taxonomic groups, and their influence can also vary with spatial scale. Yet disturbance layers are lacking at sufficiently high spatial resolution and extent to uncover these relationships with biodiversity. We detected disturbances for the conterminous United States from Landsat time series using the established LandTrendr temporal segmentation with a novel secondary classification that incorporates spatial context. We then included these disturbance layers, aggregated to metrics at different temporal and spatial scales, into model of species richness at National Ecological Observatory Network sites.  more » « less
Award ID(s):
1926567
NSF-PAR ID:
10364230
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
2021 IEEE International Geoscience and Remote Sensing Symposium IGARSS
Page Range / eLocation ID:
6252 to 6255
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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  3. Abstract

    Multiple disturbances can have mixed effects on biodiversity. Whether the interaction of sequential disturbances drives local extinctions or promotes diversity depends on the severity of biomass reductions relative to any stabilizing and/or equalizing effects generated by the disturbance regimes.

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    A freePlain Language Summarycan be found within the Supporting Information of this article.

     
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    Spatial connections between habitats are important to allow movement of organisms across heterogeneous landscapes with diverse disturbances and management. Similarly, species providing functional connections between subnetworks of species interactions (modules) are important for ecosystem services across these landscapes. These functional connectors have received less study.

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    Rapid climate change is altering plant communities around the globe fundamentally. Despite progress in understanding how plants respond to these climate shifts, accumulating evidence suggests that disturbance could not only modify expected plant responses but, in some cases, have larger impacts on compositional shifts than climate change. Climate‐driven disturbances are becoming increasingly common in many biomes and are key drivers of vegetation dynamics at both species and community levels. Palaeoecological records provide valuable observational windows for elucidating the long‐term impacts of these disturbances on plant dynamics; however, sparse resolution and difficulty in disentangling drivers of change limit our ability to understand the impact of disturbance on plant communities. In this targeted review, we highlight emerging opportunities in palaeoecology to advance our understanding about how disturbance, especially fire, impacts the ecological and evolutionary dynamics of terrestrial plant communities.

    Location

    Global examples, with many from North America.

    Conclusions

    We propose a set of palaeoecological and integrative approaches that could greatly enhance our understanding of how disturbance regimes influence global plant dynamics. Specifically, we identify four future study areas: (1) focus on palaeoecological disturbance proxies beyond fire and leverage multi proxy research to examine the influence of interacting disturbances on plant community dynamics; (2) use advances in disturbance and vegetation reconstructions, including ancient sedimentary DNA, to provide the spatial, temporal and taxonomic resolution needed to resolve the relationship between changing disturbance regimes and corresponding shifts in plant community composition; (3) integrate palaeoecological, archaeological and Indigenous knowledge to disentangle the complex interplay between climate, human land use, fire and vegetation structure; and (4) apply “functional palaeoecology” and the synergy between palaeoecology and genetics to understand how fire disturbance has served as a long‐standing selective agent on plants. These frameworks could increase the resolution of disturbance‐driven plant dynamics, potentially providing valuable information for future management.

     
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