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The Anthropocene is characterized by complex, primarily human‐generated, disturbance regimes that include combinations of long‐term press (e.g. climate change, pollution) and episodic pulse (e.g. cyclonic storms, floods, wildfires, land use change) disturbances. Within any regime, disturbances occur at multiple spatial and temporal scales, creating complex and varied interactions that influence spatiotemporal dynamics in the abundance, distribution and biodiversity of organisms. Moreover, responses to disturbance are context dependent, with the legacies of previous disturbances affecting responses to ensuing perturbations. We use three decades of annual data to evaluate the effects of repeated pulse disturbances and global warming on gastropod populations and communities in Puerto Rico at multiple spatial scales. More specifically, we quantify 1) the relative importance of large‐scale and small‐scale aspects of disturbance on variation in abundance, biodiversity and species composition; and 2) the spatial scales at which populations and communities integrate information in the spatially heterogenous environments created by disturbances. Gastropods do not exhibit consistent decreases in abundance or biodiversity in association with global warming: abundance for many species has increased over time and species richness does not evince a temporal trend. Nonetheless, gastropods are sensitive to hurricane severity, spatial environmental variation and successional trajectories of the flora. In addition, they exhibit context dependent (i.e. legacy effects) responses that are scale dependent. The Puerto Rican biota has evolved in a disturbance‐mediated system. This historical exposure to repeated, severe hurricane‐induced disturbances has imbued the biota with high resistance and resilience to the current disturbance regime, resulting in an ability to persist or thrive under current environmental conditions. Nonetheless, these ecosystems may yet be threatened by worsening direct and indirect effects of climate change. In particular, more frequent and severe hurricanes may prevent the establishment of closed canopy forests, negatively impacting populations and communities that rely on these habitats.
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This content will become publicly available on September 25, 2026
Plant Community Assembly on Volcanic Debris Avalanche Deposits around the World
Volcanic debris avalanches are among the largest and most severe disturbances known. Therefore, studying processes of ecosystem formation on the deposits emplaced by these landslides provides insights into the patterns of community assembly after the most severe disruptions. In this review we synthesize findings of 60 vegetation studies from 15 volcanic debris avalanche deposits. One of the most impactful drivers of the speed with which communities reestablish is the climatic region in which the debris avalanche occurs. The fastest recovery occurs in the tropics and slowest in the boreal latitudes. The existence of biotic legacies, or remnant soils or biota from the previous communities accelerates community establishment, and these legacies are found more frequently on smaller debris avalanche deposits. Where these legacies exist, recovery proceeds many times more rapidly than in primary successional areas of the deposits. Similar patterns across mountains are observed in the species guilds that arrive and become established on the deposits with nitrogen fixers and early seral species doing particularly well. Complete recovery, meaning that communities match those of surrounding undisturbed areas, from this extreme class of disturbance takes a very long time, decades in the tropics and centuries to millennia at higher latitudes. Secondary disturbances are frequent and often reshape the direction of community development. Understanding of community development on debris avalanches would be greatly expanded if continuous time series over decadal to millennial scales were available on more disturbances. This could be achieved through repeat monitoring of permanent plots, remote sensing, or use of pollen core analysis. Such studies may enable inference about whether long-lasting community differences from surrounding areas are due to alternative stable states or simply the slow turnover of long-lived species on volcanic debris avalanches. Further study of these topics will foster better management of human disturbed landscapes, such as those from large-scale mining.
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- Award ID(s):
- 2043870
- PAR ID:
- 10649073
- Publisher / Repository:
- Canadian Science Publishing
- Date Published:
- Journal Name:
- Environmental Reviews
- ISSN:
- 1181-8700
- Subject(s) / Keyword(s):
- long-runout landslides, vegetative succession, ecosystem regeneration, community change, large infrequent disturbance, disturbance ecology, legacies, landscape ecology
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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