Yoshimi M. Rii

University of Hawaiʻi at Mānoa | UH Manoa · Institute of Marine Biology

Spatial variability in carbon dioxide (CO 2 ) and oxygen (O 2 ) was assessed within an Indigenous Hawaiian fishpond undergoing active ecosystem restoration. The brackish, tidal fishpond is located within Kāne‘ohe Bay, Hawai‘i. Following a year of monthly discrete sampling, a significant shift in DIC and percent O 2 saturation was observed along the...

Surveys of microbial communities across transitions coupled with contextual measures of the environment provide a useful approach to dissect the factors determining distributions of microorganisms across ecological niches. Here, monthly time-series samples of surface seawater along a transect spanning the nearshore coastal environment within Kāneʻo...

A large-volume mesocosm-based nutrient perturbation experiment was conducted off the island of Hawai‘i, USA, to investigate the response of surface ocean phytoplankton communities to the addition of macronutrients, trace metals, and vitamins and to assess the feasibility of using mesocosms in the open ocean. Three free-drifting mesocosms (~60 m ³ )...

We examined variability in the euphotic zone (0–175 m) picoeukaryotic community based on time‐series observations (2011–2013) at Station ALOHA in the North Pacific Subtropical Gyre. By sampling over scales ranging from daily to approximately monthly over 2.25 years, we evaluated the resilience of the picoeukaryotic community to seasonal‐ to episodi...

As the extent of secondary forests continues to expand throughout the tropics, there is a growing need to better understand the ecosystem services, including carbon (C) storage provided by these ecosystems. Despite their spatial extent, there are limited data on how the ecosystem services provided by secondary forest may be enhanced through the res...

Time-series surveys of microbial communities coupled with contextual measures of the environment provide a useful approach to dissect the factors determining distributions of microorganisms across ecological niches. Here, monthly time-series samples of surface seawater along a transect spanning the nearshore coastal environment within Kāneʻohe Bay...

Globally, an increasing recognition of the importance of ecosystem-based management (EBM), Indigenous resource management (IRM), and Indigenous-led research and management is emerging; yet, case studies within scholarly literature illustrating comprehensive application of these theories and philosophies are scarce. We present the collaborative mana...

Here, we expand on the term “ecomimicry” to be an umbrella concept for an approach to adaptive ecosystem-based management of social-ecological systems that simultaneously optimizes multiple ecosystem services for the benefit of people and place. In this context, we define ecomimicry as a strategy for developing and managing cultural landscapes, bui...

Plain Language Summary Coral reefs are threatened by climate change stressors including ocean acidification and ocean warming. One way to measure and monitor coral reef health is to estimate coral reef calcification, which is influenced by several environmental factors including light, temperature, pH, and nutrient availability. By understanding th...

Fixed inorganic nitrogen (N) is persistently scarce in the well-lit regions of the subtropical ocean gyres and its supply plays an important role in controlling phytoplankton productivity. In a series of experiments conducted in the North Pacific Subtropical Gyre (NPSG), we examined changes in primary productivity and eukaryotic phytoplankton commu...

Bathycoccus and Ostreococcus are broadly distributed marine picoprasinophyte algae. We enumerated small phytoplankton using flow cytometry and qPCR assays for phylogenetically distinct Bathycoccus clades BI and BII and Ostreococcus clades OI and OII. Among 259 photic-zone samples from transects and time-series, Ostreococcus maxima occurred in the N...

Picophytoplankton (≤3 μm) are major contributors to plankton biomass and primary productivity in the subtropical oceans. We examined vertical and temporal variability of picophytoplankton primary productivity at near-monthly time scales (May 2012-May 2013) in the North Pacific Subtropical Gyre (NPSG) based on filter size-fractionated and flow cytom...

Picophytoplankton, including photosynthetic picoeukaryotes (PPE) and unicellular cyanobacteria, are important contributors to plankton biomass and primary productivity. In this study, phytoplankton composition and rates of carbon fixation were examined across a large trophic gradient in the South East Pacific Ocean (SEP) using a suite of approaches...

Time-series observations are critical to understand the structure, function, and dynamics of marine ecosystems. The Hawaii Ocean Time-series program has maintained near-monthly sampling at Station ALOHA (22°45′N, 158°00′W) in the oligotrophic North Pacific Subtropical Gyre (NPSG) since 1988 and has identified ecosystem variability over seasonal to...

Saying no to a move is not easy, but there could be some very good reasons to stay put, says Yoshimi Rii.

Scientists should find engaging ways to present information to their target audience, says Yoshimi Rii.

Success involves acknowledging past accomplishments as well as looking ahead to future value, says Yoshimi Rii.

Strain HIMB100 is a planktonic marine bacterium in the class Alphaproteobacteria. This strain is of interest because it is one of the first known isolates from a globally ubiquitous clade of marine bacteria known as SAR116 within the family Rhodospirillaceae. Here we describe preliminary features of the organism, together with the draft genome sequ...

E-Flux III (March 10–28, 2005) was the third and last field experiment of the E-Flux project. The main goal of the project was to investigate the physical, biological and chemical characteristics of mesoscale eddies that form in the lee of Maui and the Island of Hawai’i, focusing on the physical–biogeochemical interactions. The primary focus of E-F...

Mesoscale eddies may enhance primary production (PP) in the open ocean by bringing nutrient-rich deep waters into the euphotic zone, potentially leading to increased transport of particles to depth. This hypothesis remains controversial, however, due to a paucity of direct particle export measurements. In this study, we investigated particle dynami...

As part of E-Flux III cruise studies in March 2005, we investigated phytoplankton community dynamics in a cyclonic cold-core eddy (Cyclone Opal) in the lee of the Hawaiian Islands. Experimental incubations were conducted under in situ temperature and light conditions on a drift array using a two-treatment dilution technique. Taxon-specific estimate...

The dynamics of dissolved inorganic carbon (DIC) and processes controlling net community production (NCP) were investigated within a mature cyclonic eddy, Cyclone Opal, which formed in the lee of the main Hawaiian Islands in the subtropical North Pacific Gyre. Within the eddy core, physical and biogeochemical properties suggested that nutrient- and...

Quasi-synoptic observations of the horizontal and vertical structure of a cold-core cyclonic mesoscale eddy feature (Cyclone Noah) were conducted in the lee of Hawai’i from November 4–22, 2004 as part of the E-Flux interdisciplinary collaborative research program. Cyclone Noah appears to have spun up to the southwest of the ‘Alenuihaha Channel (bet...

Macronutrients, photosynthetic pigments, and particle export were assessed in two eddies during the E-Flux I and III cruises to investigate linkages between biogeochemical properties and export flux in Hawaiian lee cyclonic eddies. Cyclone Noah (E-Flux I), speculated to be in the ‘decay’ stage, exhibited modest increases in macronutrients and photo...

Wind-driven cyclonic eddies are hypothesized to relieve nutrient stress and enhance primary production by the upward displacement of nutrient-rich deep waters into the euphotic zone. In this study, we measured nitrate (NO3−), particulate carbon (PC), particulate nitrogen (PN), their stable isotope compositions (δ15N-NO3−, δ13C-PC and δ15N-PN, respe...

Interdisciplinary observations of mesoscale eddies were made to the west of the island of Hawai’i. A central goal of the studies is to improve our understanding of the coupling of physical, biological, and biogeochemical processes that occur within these eddies. A specific objective was to test the hypothesis that the physical mechanisms of mesosca...

As part of the E-Flux project, we documented spatial variability and temporal changes in plankton community structure in a cold-core cyclonic eddy in the lee of the Hawaiian Islands. Cyclone Opal spanned 200km in diameter, with sharply uplifted isopycnals (80–100m relative to surrounding waters) and a strongly expressed deep chlorophyll a maximum (...

Mesoscale eddies may play a critical role in ocean biogeochemistry by increasing nutrient supply, primary production, and efficiency of the biological pump, that is, the ratio of carbon export to primary production in otherwise nutrient-deficient waters. We examined a diatom bloom within a cold-core cyclonic eddy off Hawaii. Eddy primary production...