Habitat distribution, species composition and size structure of penaeid shrimps (Decapoda: Dendrobranchiata: Penaeidae) in inshore waters of Ghana

2020 ◽  
Vol 2 (1) ◽  
pp. 23
Author(s):  
Paulina Okpei ◽  
Joseph Fynn ◽  
Isaac Okyere
Keyword(s):  
Species Composition ◽  
Size Structure ◽  
Habitat Distribution ◽  
Inshore Waters ◽  
Penaeid Shrimps

scholarly journals Species Composition of Algal Epiphyton of Pink Lotus (Nymphaea pubescens Willd) Found in Laguna de Bay (Philippines)

2019 ◽  
Vol 17 (3) ◽  
pp. 237-256
Author(s):  
Eldrin De Los Reyes ARGUELLES
Keyword(s):  
Species Composition ◽  
The Philippines ◽  
Freshwater Ecosystems ◽  
Taxonomic Study ◽  
Habitat Distribution ◽  
Epiphytic Algae ◽  
Freshwater Habitats ◽  
Laguna De Bay ◽  
Root Tissues ◽  
First Time

In spite of the fact that epiphytic algae are considered an important component of freshwater ecosystems, our knowledge of their diversity and distribution is still rather poor. Taxonomic study on the composition of epiphytic algae living on submerged leaf and root tissues of macrophyte Nymphaea pubescens Willd, found at Laguna de Bay (Philippines), was conducted. In total, 21 algal taxa were identified: 10 Cyanophyceae, 6 Trebouxiophyceae, and 5 Bacillariophyceae. The taxa described in this study represent 13 orders, 16 families, 18 genera, and 21 species based on the recent combined taxonomical approach. Of these taxa, the occurrence of a rare cyanobacteria, Chroococcus schizodermaticus West, is reported for the first time in the Philippines. One species is also reported here for the first time in the Philippines, based on current taxonomic nomenclature, and this is Cyanothece aeruginosa (Nägeli) Komárek, which is based on the former name of Synechococcus aeruginosus Nägeli. These taxonomic records are considered important basal information in enriching the knowledge about the diversity and habitat distribution of cyanobacteria and microalgae in macrophytes found in freshwater habitats in the Philippines.

Variability of size structure and species composition in Caribbean octocoral communities under contrasting environmental conditions

2018 ◽  
Vol 165 (2) ◽  
Author(s):  
Georgios Tsounis ◽  
Peter J. Edmunds ◽  
Lorenzo Bramanti ◽  
Bonnie Gambrel ◽  
Howard R. Lasker
Keyword(s):  
Species Composition ◽  
Environmental Conditions ◽  
Size Structure

scholarly journals Environmental and ecological factors mediate taxonomic composition and body size of polyplacophoran assemblages along the Peruvian Province

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Christian M. Ibáñez ◽  
Melany Waldisperg ◽  
Felipe I. Torres ◽  
Sergio A. Carrasco ◽  
Javier Sellanes ◽  
...  
Keyword(s):  
Body Size ◽  
Species Composition ◽  
Size Structure ◽  
Environmental Gradients ◽  
Ecological Factors ◽  
Taxonomic Composition ◽  
Latitudinal Gradients ◽  
Size Segregation ◽  
Biogeographic Patterns ◽  
Diversity Gradient

Abstract Intertidal communities’ composition and diversity usually exhibit strong changes in relation to environmental gradients at different biogeographical scales. This study represents the first comprehensive diversity and composition description of polyplacophoran assemblages along the Peruvian Province (SE Pacific, 12°S–39°S), as a model system for ecological latitudinal gradients. A total of 4,775 chitons from 21 species were collected on twelve localities along the Peruvian Province. This sampling allowed us to quantitatively estimate the relative abundance of the species in this assemblage, and to test whether chitons conform to elementary predictions of major biogeographic patterns such as a latitudinal diversity gradient. We found that the species composition supported the division of the province into three ecoregional faunal groups (i.e. Humboldtian, Central Chile, and Araucanian). Though chiton diversity did not follow a clear latitudinal gradient, changes in species composition were dominated by smaller scale variability in salinity and temperature. Body size significantly differed by ecoregions and species, indicating latitudinal size-structure assamblages. In some localities body size ratios differed from a random assemblage, evidencing competition at local scale. Changes in composition between ecoregions influence body size structure, and their overlapping produce vertical size segregation, suggesting that competition coupled with environmental conditions structure these assemblages.

Advance regeneration and trajectories of stand development following the mountain pine beetle outbreak in boreal forests of British Columbia

2015 ◽  
Vol 45 (10) ◽  
pp. 1327-1337 ◽  
Author(s):  
Elizabeth M. Campbell ◽  
Joseph A. Antos
Keyword(s):  
British Columbia ◽  
Species Composition ◽  
Boreal Forests ◽  
Mountain Pine Beetle ◽  
Size Structure ◽  
Fire Disturbance ◽  
Active Management ◽  
Advance Regeneration ◽  
Mountain Pine ◽  
Pine Beetle

A mountain pine beetle (Dendroctonus ponderosae Hopkins) outbreak has recently spread into boreal forests, with unknown consequences for this ecosystem. We intensively sampled 12 stands affected by the current outbreak in northern British Columbia to determine the potential of western boreal forests to recover from this novel disturbance. We sampled the species composition, size structure, and spatial distribution (using 5 m × 5 m subplots, 40 per stand) of live and dead trees and used a variety of analyses, including ordinations, to assess potential developmental trajectories of stands. Advance regeneration (stems < 10 m tall) varied greatly in abundance among stands (50–18 280 stems·ha−1). However, most subplots contained at least one individual; only three stands had many empty subplots. We conclude that most stands have enough advance regeneration and residual canopy trees to form a nearly continuous new canopy. Ordinations indicate that species composition will shift substantially and become more divergent among stands. Species of high economic value will remain common, though, and active management will not be necessary in most stands to maintain productive forests. However, this novel disturbance will have very different effects on these forests than the typical fire-disturbance regime and is likely to deflect these forests into new successional trajectories.

scholarly journals Size-selective fishing drives species composition in the Celtic Sea

2012 ◽  
Vol 69 (2) ◽  
pp. 223-234 ◽  
Author(s):  
Samuel Shephard ◽  
Tak Fung ◽  
Jennifer E. Houle ◽  
Keith D. Farnsworth ◽  
David G. Reid ◽  
...  
Keyword(s):  
Species Composition ◽  
Relative Abundance ◽  
Size Structure ◽  
Large Species ◽  
Strongly Correlated ◽  
Large Fish ◽  
Fish Community Structure ◽  
Community Size ◽  
Two Indices ◽  
Celtic Sea

Abstract Shephard, S., Fung, T., Houle, J. E., Farnsworth, K. D., Reid, D. G., and Rossberg, A. G. 2012. Size-selective fishing drives species composition in the Celtic Sea. – ICES Journal of Marine Science, 69: 223–234. Fishing alters community size structure by selectively removing larger individual fish and by changing the relative abundance of different-sized species. To assess the relative importance of individual- and species-level effects, two indices of fish community structure were compared, the relative abundance of large fish individuals (large fish indicator, LFI) and the relative abundance of large fish species (large species indicator, LSI). The two indices were strongly correlated for empirical data from the Celtic Sea and for data from simulated model communities, suggesting that much of the variability in the LFI is caused by shifts in the relative abundance of species (LSI). This correlation is explained by the observation that most of the biomass of a given species is spread over few length classes, a range spanning the factor 2 of individual length, such that most species contributed predominantly to either the small or the large component of the LFI. The results suggest that the effects of size-selective fishing in the Celtic Sea are mediated mainly through changes in community composition.

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