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How fragmentation and corridors affect wind dynamics and seed dispersal in open habitats.

ABSTRACT: Determining how widespread human-induced changes such as habitat loss, landscape fragmentation, and climate instability affect populations, communities, and ecosystems is one of the most pressing environmental challenges. Critical to this challenge is understanding how these changes are affecting the movement abilities and dispersal trajectories of organisms and what role conservation planning can play in promoting movement among remaining fragments of suitable habitat. Whereas evidence is mounting for how conservation strategies such as corridors impact animal movement, virtually nothing is known for species dispersed by wind, which are often mistakenly assumed to not be limited by dispersal. Here, we combine mechanistic dispersal models, wind measurements, and seed releases in a large-scale experimental landscape to show that habitat corridors affect wind dynamics and seed dispersal by redirecting and bellowing airflow and by increasing the likelihood of seed uplift. Wind direction interacts with landscape orientation to determine when corridors provide connectivity. Our results predict positive impacts of connectivity and patch shape on species richness of wind-dispersed plants, which we empirically illustrate using 12 y of data from our experimental landscapes. We conclude that habitat fragmentation and corridors strongly impact the movement of wind-dispersed species, which has community-level consequences.

SUBMITTER: Damschen EI

PROVIDER: S-EPMC3948294 | biostudies-literature | 2014 Mar

REPOSITORIES: biostudies-literature

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How fragmentation and corridors affect wind dynamics and seed dispersal in open habitats.

Damschen Ellen I EI Baker Dirk V DV Bohrer Gil G Nathan Ran R Orrock John L JL Turner Jay R JR Brudvig Lars A LA Haddad Nick M NM Levey Douglas J DJ Tewksbury Joshua J JJ

Proceedings of the National Academy of Sciences of the United States of America 20140224 9

Determining how widespread human-induced changes such as habitat loss, landscape fragmentation, and climate instability affect populations, communities, and ecosystems is one of the most pressing environmental challenges. Critical to this challenge is understanding how these changes are affecting the movement abilities and dispersal trajectories of organisms and what role conservation planning can play in promoting movement among remaining fragments of suitable habitat. Whereas evidence is mount ...[more]

PMID: 24567398

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How fragmentation and corridors affect wind dynamics and seed dispersal in open habitats.

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How fragmentation and corridors affect wind dynamics and seed dispersal in open habitats.

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