What’s more, scientists have used this data to draw new connections between the levels of faunal diversity and the heterogeneity of submarine canyon landscapes at various spatial scales.
Researchers sampled diversity in Hawaii's submarine canyons, including these off Kaneohe Bay.
“Submarine canyons encompass myriad habitat types,” said Fabio C. De Leo, a doctoral graduate from UH Mânoa’s department of oceanography and the lead author on a new paper that was recently published in the scientific journal Deep Sea Research Part II. “This heterogeneity at the landscape-scale helps to enhance local biodiversity in canyon seafloor sediments.”
De Leo and colleagues, including oceanography professor Craig Smith, the study’s principal investigator (PI), conducted 34 submersible dives into six underwater canyons and their nearby slopes. Plumbing depths of up to 1,500 meters (~5,000 feet), their study area ranged across the Hawaiian archipelago, from the main Hawaiian Islands through Papahânaumokuâkea Marine National Monument in the Northwestern Hawaiian Islands.
The scientists evaluated and mapped landscape metrics of each canyon habitat, including the roughness of the seafloor and the steepness of canyon walls. At depths of 350, 650, and 1,000 meters in each location, they collected sediment core samples on the canyon floor. From these samples, they carefully sorted out and identified all of the marine organisms called macrobenthos—including worms, clams and shrimp-like crutaceans— that range in size from a millimeter to several centimeters. The scientists then correlated the macrobenthos species data with the landscape metrics.
The scientists found that submarine canyons can serve as species oases in the sea by channeling ocean currents, capturing and trapping sinking particles, funneling migrating animals, and generally providing a varied physical landscape. As a result, canyons promote high species diversity.
Researchers say this is the first study of its kind to thoroughly examine submarine canyons on island margins. The research effort had previously yielded reports of high species diversity of fish and large invertebrates, the so-called megafauna, in Hawai‘i’s submarine canyons. This corroboration led them to conclude: “Canyons may be particularly important in the Hawaiian islands, in part because they supply organic matter to the typically food-limited deep sea,” De Leo said. “When there’s more food, there’s more life.”
One thing that became evident from this study was that canyons near the main Hawaiian islands tended to collect and hold much more land-based organic matter than canyons in the Northwestern Hawaiian Islands. Materials such as branches, leaves, nuts and algae were abundant off Moloka‘i and O‘ahu, washed into the ocean by rain and carried out deep onto the canyon floors by ocean currents. These decomposing materials, scarcer in the islands of Nihoa and Maro Reef, serve as valuable food sources for the seafloor invertebrates, themselves a food source for other, larger fish.
The scientists have already documented four new species discovered during the course of their research dives, including three new types of crustaceans. Up to 60 percent of the species that taxonomists identified in the submarine canyon seafloor samples are only recognized to the family level.
“There is room for discovery of many more new species,” De Leo said. “The deep sea fauna of Hawai‘i is poorly sampled and poorly understood. Every time we go to sea and sample a new area, it’s likely that we’ll find a new species.”
This series of dives was conducted on the Pisces IV and Pisces V manned submersibles operated by the Hawai‘i Undersea Research Laboratory (HURL). The research was conducted in partnership with Hawai‘i Pacific University and the New Zealand National Institute of Water and Atmospheric Research.
Citation: Fabio C. De Leo, E.W. Vetter, C. R. Smith, A. R. Ashley, and M. McGranaghan. Spatial scale-dependent habitat heterogeneity influences submarine canyon macrofaunal abundance and diversity off the Main and Northwest Hawaiian Islands. Deep Sea Research Part II: Topical Studies in Oceanography. 11 July 2013.
Support: This study of submarine canyons off the main and Northwestern Hawaiian Islands was supported by grants from NOAA Office of Ocean Exploration and Research (PIs C.R. Smith and E.W. Vetter), HURL, and the Census of Diversity of Abyssal Marine Life (CeDAMar, PI C.R. Smith). F. De Leo was also funded through a 4-year Ph.D. fellowship from the Brazilian Ministry of Education (Capes) in partnership with Fulbright.
For more information, visit: http://www.soest.hawaii.edu/HURL/
GPM sees deadly tornadic storms moving through US Southeast
01.12.2016 | NASA/Goddard Space Flight Center
Cyclic change within magma reservoirs significantly affects the explosivity of volcanic eruptions
30.11.2016 | Johannes Gutenberg-Universität Mainz
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.
The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...
Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water
In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...
The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.
Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with partners have investigated how these materials can be used to make power...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
02.12.2016 | Medical Engineering
02.12.2016 | Agricultural and Forestry Science
02.12.2016 | Physics and Astronomy