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Abstract Essential to life on Earth, assessment of marine photosynthesis is of paramount importance. Photosynthesis occurs in spatially discrete microscopic entities at various levels of biological organization, from subcellular chloroplasts to symbiotic microalgae and macroalgae, and is influenced by the surrounding conditions.As such, in situ photosynthetic efficiency mapping on appropriate scales holds great promise for learning about these processes.To achieve this goal, we designed, fabricated, and tested an underwater microscope that incorporates standard colour, epifluorescence, and variable chlorophyllafluorescence imaging with nearly micron spatial resolution that resolves the structure and photosynthetic efficiency of benthic organisms.Our results highlight coral observations with high‐resolution photosynthetic spatial variability and detailed morphology. Our imaging system therefore enables research never before possible on the health and physiology of benthic aquatic organisms in situ, placing it in the context of their physical and biological environment.
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Spatial and temporal patterns in Arctic mosquito abundance
Abstract Organisms that undergo a shift in ontogeny and habitat type often change their spatial distribution throughout their life cycle, but how this affects population dynamics remains poorly understood.We examined spatial and temporal patterns inAedes nigripesabundance, a widespread univoltine Arctic mosquito species (Diptera: Culicidae), hypothesizing that the spatial distribution of adults would be closely tied to aquatic habitat.We tracked adult densities ofA. nigripesnear Kangerlussuaq, Greenland using emergence traps, CO2‐baited traps, and sweep‐nets.In back‐to‐back years of sampling (2017 and 2018) we found two‐fold variation in overall abundance.Adults were spatially patchy when first emerging from aquatic habitats but within a week, mean capture rates for host‐seeking adult females were similar across locations, even in places far from larval habitat.Daily variation in mosquito captures was primarily explained by weather, with virtually no mosquito activity when temperatures averaged less than 8°C or wind speeds exceeded 6 m/s. Gravid females (3% of resting adults) were spatially patchy on the landscape, but not always in the same places where most adults emerged.The spatial distribution of adults is quickly uncoupled from the spatial distribution of larvae becauseA. nigripesfemales may disperse far from their natal habitats in search of a blood‐meal and high‐quality oviposition habitat. 8. This research highlights the value of studying ecological processes that act at disparate life stages for understanding the population biology of organisms with complex life cycles.
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- Award ID(s):
- 2019528
- PAR ID:
- 10443008
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Ecological Entomology
- Volume:
- 48
- Issue:
- 1
- ISSN:
- 0307-6946
- Format(s):
- Medium: X Size: p. 19-30
- Size(s):
- p. 19-30
- Sponsoring Org:
- National Science Foundation
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