Deep and Bottom Currents in the Challenger Deep, Mariana Trench, Measured with Super-Deep Current Meters

Taira, Keisuke; Kitagawa, Sho; Yamashiro, Toru; Yanagimoto, Daigo

doi:10.1007/s10872-005-0001-y

Cited by 73 publications

(44 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This observation suggested that the hadal microbial biosphere was supported by the endogenous recycling of organic matter in the hadal waters associated with the trench geomorphology. similar to previous observations, and the salinity slightly increased at depths greater than 9,000 m below the surface (mbs) (8,9,18). The sea surface temperature was 29.1°C; the potential temperature decreased to 1.02°C at 10,257 mbs.…”

Section: Resultssupporting

confidence: 88%

“…The microbial heterotrophic populations influenced by the suspended organic matter were similar to those found in the Challenger Deep hadal biosphere that were enriched by heterotrophs. A steep slope, narrow geomorphology, slow trench current (8,9), and earthquakes may supply a steady state or the occasional input of sinking and suspended organic matter. Because suspended particulate matters are transported vertically as well as horizontally (42,43), the suspended organic matter from slopes likely influences the geochemical cycle in the entire trench waters.…”

Section: Discussionmentioning

confidence: 99%

“…Trench environments are differentiated from upper abyssal oceans by their elevated hydrostatic pressure and their hydrotopographically isolated nature, whereas other physical and chemical conditions, such as temperature, salinity, dissolved oxygen, and nutrients are comparable to those in abyssal oceans (7)(8)(9). The microbiological and geochemical investigations of hadal waters have been limited (10), in contrast to the long history of hadal benthic microbiological studies occurring since the 1950s (11).…”

mentioning

confidence: 99%

“…The Challenger Deep in the Mariana Trench is the deepest ocean on Earth, and its geology, current patterns, water chemistries, and benthic microbial communities have been relatively well studied (8,9,(13)(14)(15)(16)(17). However, the hadal aquatic microbial communities in the Challenger Deep remain completely uncharacterized.…”

mentioning

confidence: 99%

See 3 more Smart Citations

Hadal biosphere: Insight into the microbial ecosystem in the deepest ocean on Earth

Nunoura

Takaki

Hirai

et al. 2015

Proc. Natl. Acad. Sci. U.S.A.

260

314

View full text Add to dashboard Cite

Hadal oceans at water depths below 6,000 m are the least-explored aquatic biosphere. The Challenger Deep, located in the western equatorial Pacific, with a water depth of ∼11 km, is the deepest ocean on Earth. Microbial communities associated with waters from the sea surface to the trench bottom (0 ∼10,257 m) in the Challenger Deep were analyzed, and unprecedented trench microbial communities were identified in the hadal waters (6,000 ∼10,257 m) that were distinct from the abyssal microbial communities. The potentially chemolithotrophic populations were less abundant in the hadal water than those in the upper abyssal waters. The emerging members of chemolithotrophic nitrifiers in the hadal water that likely adapt to the higher flux of electron donors were also different from those in the abyssal waters that adapt to the lower flux of electron donors. Species-level niche separation in most of the dominant taxa was also found between the hadal and abyssal microbial communities. Considering the geomorphology and the isolated hydrotopographical nature of the Mariana Trench, we hypothesized that the distinct hadal microbial ecosystem was driven by the endogenous recycling of organic matter in the hadal waters associated with the trench geomorphology.hadal | trench | niche separation | nitrification | Challenger Deep

show abstract

Section: Resultssupporting

confidence: 88%

Section: Discussionmentioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%

See 2 more Smart Citations

Hadal biosphere: Insight into the microbial ecosystem in the deepest ocean on Earth

Nunoura

Takaki

Hirai

et al. 2015

Proc. Natl. Acad. Sci. U.S.A.

260

314

View full text Add to dashboard Cite

show abstract

“…With the assumed reference level of 5500 dbar, the water was flowing eastwards between the two pairs of stations in the southern area of the short meridional transect along 145°E, and westwards near the corner point 4 . However, several current meters along 142°35′E in the Mariana Trench showed a mean westwards flow 5 . CTD data collected in November 2016 revealed that the average turbulence between 6500 and 8500 m in the Challenger Deep is a magnitude of ten times higher than that between 10300 and 10850 m 6 .…”

Section: Introductionmentioning

confidence: 97%

Seasonal variability of water characteristics in the Challenger Deep observed by four cruises

Huang

Xie

Wang

et al. 2018

Sci Rep

View full text Add to dashboard Cite

Thirty conductivity-temperature-depth profiler casts in the Challenger Deep were conducted during four cruises from December 2015 to February 2017. Two cruises took place in the summer, and two in the winter. The results demonstrated that water characteristics varied seasonally. The temperature minimum values were the same between the four cruises, but its depth was noticeably shallower in the winter than that in the summer. The θ-S diagram indicated that deep water is more saline in the summer than that in winter at the same potential temperature. Mixing is more intense between 5000 and 6800 m in the summer than that in the winter. The dissipation rate and eddy diffusivity vertically averaged between 5000 and 6800 m in the summer were εT = 3.277 × 10−8 m2s−3 and KzT = 2.58 × 10−2 m2s−1, respectively. The geostrophic flows below the reference level of 3000 dbar were cyclonic in the summer, travelling westwards in the northern and eastwards in the southern areas of the Challenger Deep.

show abstract

Sediment Accumulation and Carbon Burial in Four Hadal Trench Systems

Oguri

Masqué

Zabel

et al. 2022

Preprint

View full text Add to dashboard Cite

Hadal trenches are considered to act as depocenters for organic material, although pathways for the material transport and deposition rates are poorly constrained. Here we assess focusing, deposition and accumulation of material and organic carbon in four hadal trench systems underlying different surface ocean productivities; the eutrophic Atacama and Kuril-Kamchatka trenches, the mesotrophic Kermadec trench and the oligotrophic Mariana Trench. The study is based on the distributions of naturally occurring 210 Pb ex , 137 Cs and total organic carbon from recovered sediment cores and by applying previously quantified benthic mineralization rates. Periods of steady deposition and discreet mass-wasting deposits were identified from the profiles and the latter were associated with historic recorded seismic events in the respective regions. During periods without mass wasting, the estimated focusing factors along trench axes were elevated, suggesting more or less continuous downslope focusing of material toward the interior of the trenches. The estimated organic carbon deposition rates during these periods exhibited extensive site-specific variability, but were generally similar to values encountered at much shallower settings such as continental slopes and margins. Organic carbon deposition rates during periods of steady deposition were not mirrored by surface ocean productivity, but appeared confounded by local bathymetry. The inclusion of deposition mediated by mass-wasting events enhanced the sediment and organic carbon accumulations for the past ∼150 years by up to a factor of ∼4. Thus, due to intensified downslope material focusing and infrequent mass-wasting events, hadal trenches are important sites for deposition and sequestration of organic carbon in the deep sea.Plain Language Summary Hadal trenches (>6,000 m water depth) occupy ∼1% of the world's ocean floor yet are largely underexplored, but recent studies have shown that these environments are depocenters for organic material and microbial activity is intensified when compared to shallower abyssal plains. However, transport and accumulation of sediment material to these hadal trenches is poorly understood. This study investigates sedimentation and accumulation dynamics of organic carbon in trenches using results of radionuclide analysis (in sediment from the Atacama, Kuril-Kamchatka, Kermadec, and Mariana trenches). The analysis shows that trench sediments consist of discreet layers representing both periods of continuous deposition and sudden mass-wasting events often triggered by historic earthquakes. Down slope focusing of material, intensified the deposition along the trench axes. However, the deposition rates exhibited extensive site-specific variations that were partly related to mass-wasting events which greatly enhanced not only mass accumulation but also organic carbon accumulation at the trench axes. Our results illustrate that mass-wasting events play an important role on supplying organic carbon to hadal communities and suggest that hadal tr...

show abstract

Deep and Bottom Currents in the Challenger Deep, Mariana Trench, Measured with Super-Deep Current Meters

Cited by 73 publications

References 7 publications

Hadal biosphere: Insight into the microbial ecosystem in the deepest ocean on Earth

Hadal biosphere: Insight into the microbial ecosystem in the deepest ocean on Earth

Seasonal variability of water characteristics in the Challenger Deep observed by four cruises

Sediment Accumulation and Carbon Burial in Four Hadal Trench Systems

Contact Info

Product

Resources

About