The California Current System displays a strong seasonal cycle in water properties, circulation, and biological production. Interactions of the alongshore current with coastal and topographic features lead to high spatial variability forced by seasonal winds that displace surface coastal water offshore. This process also supplies nutrients to the euphotic zone by Ekman transport and eventually supports phytoplankton blooms typically dominated by diatoms. Here, we investigate the relationship between biogenic silica production and mesoscale upwelling dynamics along the central region of the California Current System between 2013 and 2015, a period affected by a warm anomaly known as “the Blob.” Changes in the upwelling phenology along California caused by this marine heatwave are investigated using an innovative index and related to patterns of diatom production during upwelling events to evaluate diatom resilience. Based on this new index, we estimated that the nutrient supply to the euphotic zone declined by 50% during the Blob, but the Blob had little impact on local production during individual upwelling events. A statistical analysis evaluating the relationship between production and environmental conditions reveals persistent biological hotspots characterized by high biomass, depleted nutrients, and high specific production rates (up to 0.7 d−1) throughout the study period. Lower observed biogenic silica to Chlorophyll
Spatiotemporal variability in primary producer growth rates is a fundamental aspect of community structure. Understanding drivers of these patterns and their response to climate variability and change are ongoing challenges. Nutrient and light limitations often are invoked as proximate drivers of these patterns, but many other environmental and biological factors vary across spatial and temporal scales. In temperate rocky intertidal habitats, macrophytes are major space occupiers and the base of the food web, and thus their patterns of primary production relate directly to their functions and services in these communities. We investigated spatiotemporal patterns of the primary production of two species of macrophytes, the kelp
- NSF-PAR ID:
- 10443845
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Limnology and Oceanography
- Volume:
- 66
- Issue:
- 3
- ISSN:
- 0024-3590
- Page Range / eLocation ID:
- p. 711-726
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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