Picophytoplankton abundance and community structure in the Philippine Sea, western Pacific

2010 ◽  
Vol 28 (1) ◽  
pp. 88-95 ◽  
Author(s):  
Sanjun Zhao ◽  
Jianwei Wei ◽  
Haidong Yue ◽  
Tian Xiao
Keyword(s):  
Community Structure ◽  
Western Pacific ◽  
Philippine Sea

scholarly journals Interdecadal Change of the South China Sea Summer Monsoon Onset

2012 ◽  
Vol 25 (9) ◽  
pp. 3207-3218 ◽  
Author(s):  
Yoshiyuki Kajikawa ◽  
Bin Wang
Keyword(s):  
South China Sea ◽  
Summer Monsoon ◽  
South China ◽  
The South China Sea ◽  
Western Pacific ◽  
Significant Advance ◽  
Interdecadal Change ◽  
The South ◽  
China Sea ◽  
Philippine Sea

A significant advance in the onset dates of the South China Sea summer monsoon (SCSSM) is detected around 1993/94: the epochal mean onset date is 30 May for 1979–93 and 14 May for 1994–2008. The relatively late onset during the first epoch is primarily determined by the northward seasonal march of the intertropical convergence zone, whereas the advanced onset during the second epoch is affected by the enhanced activity of northwestward-moving tropical disturbances from the equatorial western Pacific. During 1994–2008, the intraseasonal variability (ISV) over the western Pacific was enhanced during the period from mid-April to mid-May; further, the number of tropical cyclones (TCs), which passed through the South China Sea (SCS) and Philippine Sea during the same period, is about doubled compared with those occurring during 1979–93. This enhanced ISV and TC activity over the SCS and Philippine Sea are attributed to a significant increase in SST over the equatorial western Pacific from the 1980s to 2000s. Therefore, the advanced SCSSM onset is rooted in the decadal change of the SST over the equatorial western Pacific.

Diversity and Community Structure of Archaea in Deep Subsurface Sediments from the Tropical Western Pacific

2009 ◽  
Vol 60 (6) ◽  
pp. 439-445 ◽  
Author(s):  
Wei Zhang ◽  
Gaowa Saren ◽  
Tiegang Li ◽  
Xinke Yu ◽  
Linbao Zhang
Keyword(s):  
Community Structure ◽  
Western Pacific ◽  
Deep Subsurface ◽  
Tropical Western Pacific ◽  
Subsurface Sediments

scholarly journals Nutrient ratios driven by vertical stratification regulate phytoplankton community structure in the oligotrophic western Pacific Ocean

Ocean Science ◽  
2021 ◽  
Vol 17 (6) ◽  
pp. 1775-1789
Author(s):  
Zhuo Chen ◽  
Jun Sun ◽  
Ting Gu ◽  
Guicheng Zhang ◽  
Yuqiu Wei
Keyword(s):  
Spatial Distribution ◽  
Community Structure ◽  
Pacific Ocean ◽  
Phytoplankton Community ◽  
Western Pacific ◽  
Vertical Stratification ◽  
Nutrient Ratios ◽  
Western Pacific Ocean ◽  
Phytoplankton Community Structure ◽  
Phytoplankton Abundance

Abstract. The stratification of the upper oligotrophic ocean has a direct impact on biogeochemistry by regulating the components of the upper-ocean environment that are critical to biological productivity, such as light availability for photosynthesis and nutrient supply from the deep ocean. We investigated the spatial distribution pattern and diversity of phytoplankton communities in the western Pacific Ocean (WPO) in the autumn of 2016, 2017, and 2018. Our results showed the phytoplankton community structure mainly consisted of cyanobacteria, diatoms, and dinoflagellates, while the abundance of Chrysophyceae was negligible. Phytoplankton abundance was high from the equatorial region to 10∘ N and decreased with increasing latitude in spatial distribution. Phytoplankton also showed a strong variation in the vertical distribution. The potential influences of physicochemical parameters on phytoplankton abundance were analyzed by a structural equation model (SEM) to determine nutrient ratios driven by vertical stratification to regulate phytoplankton community structure in the typical oligotrophic ocean. Regions with strong vertical stratification were more favorable for cyanobacteria, whereas weak vertical stratification was more conducive to diatoms and dinoflagellates. Our study shows that stratification is a major determinant of phytoplankton community structure and highlights that physical processes in the ocean control phytoplankton community structure by driving the balance of chemical elements, providing a database to better predict models of changes in phytoplankton community structure under future ocean scenarios.

Chemical Geodynamics of Asthenospheric Outflow in the western Pacific: Philippine Sea Back-arc Basin Mantle Source of the Yap Trench Forearc Lavas

2020 ◽  
Author(s):  
Limei Tang ◽  
Ling Chen
Keyword(s):  
Trace Element ◽  
Western Pacific ◽  
Philippine Sea Plate ◽  
Philippine Sea ◽  
Trace Element Chemistry ◽  
Lithospheric Extension ◽  
Mid Ocean Ridge ◽  
Back Arc ◽  
Ocean Ridge ◽  
The Western Pacific

<p>We present new major and trace element chemistry and Sr, Nd, and Pb isotope data from basalts, recovered from the forearc setting of the Yap Trench in the western Pacific, and discuss their melt evolution and petrogenesis within the framework of the geodynamic interactions among the Caroline Plate, the Caroline ridge, and the Philippine Sea plate. These rocks have mid-ocean ridge basalt (MORB)-like geochemical features, including medium Fe contents, tholeiitic affinity, high TiO<sub>2</sub> values at a given Fe<sub>2</sub>O<sub>3</sub>/MgO ratio, Ti/V, Nb/Y, Ba/Yb, and Ba/Th ratios similar to those of back-arc basin basalts (BABB), and trace element patterns commonly displayed by MORB and BABB lavas. However, these basalts are characterized by highly radiogenic Sr and Pb contents, reminiscent of western Pacific sediments. We suggest that forearc magmatism was responsible for the origin and petrogenesis of these rocks. Forearc magmatism was induced by the shrinking of the Philippine Sea plate, which squeezed out the underlying back-arc basin asthenosphere with Indian–type ambient mantle characteristics to invade the forearc mantle of the Yap Trench and causes lithospheric extension. Upwelling and decompression melting of this mantle produced MORB-like lavas in the narrow forearc setting. An apparent slab tear or gap in the subducting plate facilitate the penetration of the mantle outflow. The collision of the Caroline Ridge subducted more sediments into the mantle wedge. Melting of the subducted sediments and the invasion of the Indian-type asthenosphere into the forearc account for the highly radioactive Sr and Pb isotopes of the MORB-like lavas.</p>

Sign in / Sign up

Export Citation Format

Share Document