scholarly journals The spatio-temporal evolution of the genus Nitzschia Longissima at the level of the lagoon in Nador, Morocco

2021 ◽  
Vol 234 ◽  
pp. 00081
Author(s):  
Ouassila Riouchi ◽  
Faid El Madani ◽  
Eric Abadie ◽  
Ali Skalli ◽  
Mourad Baghour

This work aims to study the spatio-temporal evolution of the genus Nitzschia longissima, one of the most important genera of marine plankton diatoms, from 3 sampling stations in the Nador lagoon and during 2 seasons (spring and summer 2018), Using Nitzschia longissima, as a study system, one of the most diverse and abundant genera among marine planktonic diatoms. This species counts, in addition to the form Nitzschia longissima forma parva Grunow, three varieties namely Nitzschia longissima var. closterium (W. Smith) Van Heurck, Nitzschia longissima var. longissima (Breb.) Ralfs and Nitzschia longissima var. reversa Grunow. Nitzschia Longissima genus density was high during the warm season (Summer 2018) with a value of 8000 cells/liter, and low during the cold seasons (Spring 2018), which may be caused by water temperature and zooplankton community structure; and underwater light intensity was an important factor influencing the spatial distribution of Nitzschia density.

2012 ◽  
Vol 4 (2) ◽  
Author(s):  
Arief Rachman ◽  
Elly Asniariati

<p>Banggai Sea is an interesting ecosystem due to mixing influences from Banda Sea in the west and Maluccas Sea in the east. Therefore, a unique zooplankton community structure and specific distribution pattern should be found in this area. This research was carried on using Baruna Jaya VIII research vessel and samples were collected in 14 sampling stations. Vertical towing using NORPAC plankton net (300 μm) was conducted to collect zooplankton samples. Result showed that inner Mesamat Bay had the lowest abundance of zooplankton, probably due to low water quality resulted from anthropogenic activity. Meanwhile the strait between Liang and Labobo Island had the highest zooplankton abundance in Banggai Sea. Calanoids was the dominant zooplankton taxa in the ecosystem and contributing 55.7% of total density of zooplankton community. The highest importance value made this taxa to be very important factor that regulates the lower trophic level organisms. Results also showed that zooplankton was distributed nearly uniform in eastern but aggregated to several stations in western Banggai Sea. Zooplankton abundance was higher in the central of Banggai Sea, compared to western and eastern area. According to Bray-Curtis clustering analysis the strait between Liang and Labobo Island has unique zooplankton community structure. This might happened due to mixing of water from two highly productive seas that influenced the Banggai Sea ecosystem. From this research we conclude that this strait probably was the zooplankton hot spot area which might also indicate that this area also a hot spot of fishes in the Banggai Sea.</p><p>Keywords: spatial distribution, zooplankton, community structure, hot spot, Banggai</p>


2019 ◽  
Vol 8 (1) ◽  
Author(s):  
Siti Balqis Abd. Razak ◽  
Zati Sharip

AbstractThe ecological impacts of urbanization and eutrophication on zooplankton communities in urban waterbodies have recently gained wide interest. Study findings vary across species and urban waterbodies. How the development of such changes affects the variation of biotic assemblages has only been explored to a limited extent in tropical urban lakes.Spatial and temporal variations of zooplankton community structure in 11 urban waterbodies in the Klang Valley, Malaysia were investigated along trophic and urbanization gradients. Zooplankton and water quality samples were collected three times, between May and November 2017, from two different locations in each lake. All three main zooplankton groups (rotifera, copepoda, and cladocera) were recorded from the study areas throughout the sampling period. The zooplankton community structure, particularly with regard to rotifers and cladocerans, varied between lakes and seasons. Zooplankton diversity does not vary with lake size or distance from the city center but does vary with shoreline development index and urbanization impacts. The zooplankton populations were dominated by rotifers, mainly Brachionus angularis at all study sites during the study period followed by copepods and cladocerans. The total density of zooplankton was significantly highest (p < 0.05) in the hypereutrophic lakes and during the dry season. Zooplankton diversity and rotifer species richness were negatively correlated with total phosphorus (TP). Diversity increased with urbanization and shoreline development, with rotifers as a potential bioindicator of trophic state in urban tropical lakes, due to their close relationship with TP.


2012 ◽  
Vol 4 (2) ◽  
Author(s):  
Arief Rachman ◽  
Elly Asniariati

Banggai Sea is an interesting ecosystem due to mixing influences from Banda Sea in the west and Maluccas Sea in the east. Therefore, a unique zooplankton community structure and specific distribution pattern should be found in this area. This research was carried on using Baruna Jaya VIII research vessel and samples were collected in 14 sampling stations. Vertical towing using NORPAC plankton net (300 μm) was conducted to collect zooplankton samples. Result showed that inner Mesamat Bay had the lowest abundance of zooplankton, probably due to low water quality resulted from anthropogenic activity. Meanwhile the strait between Liang and Labobo Island had the highest zooplankton abundance in Banggai Sea. Calanoids was the dominant zooplankton taxa in the ecosystem and contributing 55.7% of total density of zooplankton community. The highest importance value made this taxa to be very important factor that regulates the lower trophic level organisms. Results also showed that zooplankton was distributed nearly uniform in eastern but aggregated to several stations in western Banggai Sea. Zooplankton abundance was higher in the central of Banggai Sea, compared to western and eastern area. According to Bray-Curtis clustering analysis the strait between Liang and Labobo Island has unique zooplankton community structure. This might happened due to mixing of water from two highly productive seas that influenced the Banggai Sea ecosystem. From this research we conclude that this strait probably was the zooplankton hot spot area which might also indicate that this area also a hot spot of fishes in the Banggai Sea.Keywords: spatial distribution, zooplankton, community structure, hot spot, Banggai


2009 ◽  
Vol 33 (3) ◽  
pp. 556-561
Author(s):  
Gui-Jun YANG ◽  
Bo-Qiang QIN ◽  
Guang GAO ◽  
Xiao-Dong WANG ◽  
Hong-Yan WANG

Hydrobiologia ◽  
2009 ◽  
Vol 632 (1) ◽  
pp. 225-233 ◽  
Author(s):  
S. Matthew Drenner ◽  
Stanley I. Dodson ◽  
Ray W. Drenner ◽  
John E. Pinder III

Sign in / Sign up

Export Citation Format

Share Document