scholarly journals Niche overlap of benthic macrofauna in a tropical estuary: diurnal variation

2021 ◽  
Vol 13 (13) ◽  
pp. 20000-20010
Author(s):  
Mário Herculano de Oliveira ◽  
Lidiane Gomes de Lima ◽  
Caroline Stefani da Silva Lima ◽  
Jéssica de Oliveira Lima Gomes ◽  
Franciely Ferreira Paiva ◽  
...  
Keyword(s):  
Diurnal Variation ◽  
River Estuary ◽  
Niche Overlap ◽  
Water Levels ◽  
Survival Strategies ◽  
Macroinvertebrate Communities ◽  
Data Sampling ◽  
Structure Of Communities ◽  
Composition And Structure ◽  
Diurnal Period

The complexity of estuaries allows for the establishment of diverse communities composed of species with different survival strategies. The vertical migration of animals in the sediment is linked to competition, escape from predators and adaptations to diurnal physio-chemical changes related to variations in water levels. The present study aimed to evaluate niche overlap and amplitude, as well as the composition and structure, of communities of polychaetes and molluscs between sediment aliquots during the day and at night. Data sampling was performed in the Tubarão River estuary. The highest individual occurrence was registered during the diurnal period. Communities of polychaetes varied significantly between sediment aliquots during the day and at night, while molluscs did not show diurnal variation. Niche overlap results for polychaetes showed higher values between aliquots during the night, while molluscs showed greater overlap during the day. This indicates that polychaetes and molluscs have different mechanisms of coexistence. This may be related to different attributes of species allowing for the division of resources among individuals. Examination of niche overlap provides insights into coexistence of mechanisms within benthic macroinvertebrate communities.

Dietary overlap and food resource partitioning among fish species of a tropical estuary in Northeastern Brazil

Gaia Scientia ◽  
2016 ◽  
Vol 10 (4) ◽  
pp. 86-95 ◽  
Author(s):  
Adna Ferreira da Silva Garcia ◽  
Ana Lúcia Vendel
Keyword(s):  
Resource Partitioning ◽  
Species Coexistence ◽  
Food Resource ◽  
River Estuary ◽  
Niche Overlap ◽  
Northeastern Brazil ◽  
Dietary Overlap ◽  
Feeding Niche ◽  
Tropical Environments ◽  
Food Resource Partitioning

The current work investigates dietary overlap and food partitioning among nine abundant carnivorous fishes caught in the shallow waters of the Paraíba do Norte river estuary, Paraíba State, Brazil. Fishes were sampled with a beach seine net between January and December 2008 and a total of 958 specimens had their stomach content analyzed. Crustacea was the dominant food resource for Lutjanus alexandrei, L. jocu and Bathygobius soporator, whereas Telostei were consumed mainly by Centropomus undecimalis and C. parallelus. In contrast, Polychaeta were preyed upon mainly by Diapterus rhombeus, Eucinostomus argenteus, Sciades herzbergii and S. parkeri. Although most species consumed similar food items, they did that in varying proportions and amounts. Overall, the niche overlap among species was low (< 0.60), but there were several cases where pair of species had their feeding niche highly overlapped (between 0.72 and 0.97). These findings corroborate the hypothesis that food resource partitioning determines species coexistence in estuarine tropical environments.

scholarly journals Ecology of colonizing populations of the figfly Zaprionus indianus (Diptera, Drosophilidae) in Porto Alegre, Southern Brazil

2005 ◽  
Vol 95 (3) ◽  
pp. 233-240 ◽  
Author(s):  
Norma Machado da Silva ◽  
Carina da Conceição Fantinel ◽  
Vera Lucia da Silva Valente ◽  
Vitor Hugo Valiati
Keyword(s):  
Niche Breadth ◽  
Niche Overlap ◽  
Trophic Niche ◽  
Survival Strategies ◽  
Porto Alegre ◽  
Zaprionus Indianus ◽  
Feeding Sites ◽  
Substrate Choice ◽  
Oviposition Substrate ◽  
Feeding Substrate

Ecological parameters such as trophic niche overlap and niche breadth were computed from the frequency of all drosophilid species collected in 2001 and 2002, in the urban area of Porto Alegre city, Brazil. Independently of place, drosophilids community composition and components breeding or feeding sites, the highest frequencies of Zaprionus indianus (Gupta, 1970) were obtained during seasons with higher average temperatures, especially during summer. From a total of the 19,146 individuals of Z. indianus sampled, 80% were found in this season. The data of trophic niche breadth suggest a higher opportunism of adult flies in feeding substrate use, but the females are still selective in oviposition substrate choice. For the values of niche overlap, only for some species, did we find any correlation between these and species richness and/or number of resources, and the most of the correlation values considering breeding and feeding sites were positive. The colonization of Z. indianus in Porto Alegre could be leading to adjustments in the survival strategies of the resident species, but it is possible that many species have conditions for coexisting with the invader.

scholarly journals ARTIFICIAL BREACHINGS OF BOT RIVER ESTUARY

1982 ◽  
Vol 1 (18) ◽  
pp. 148
Author(s):  
G.A.W. Fromme
Keyword(s):  
River Estuary ◽  
High Water ◽  
Coastal Engineering ◽  
Water Levels ◽  
Freshwater Lake ◽  
Management Policy ◽  
Western Cape ◽  
National Research Institute ◽  
Conflicting Interests ◽  
Sand Bar

During the flood year of 1981 the "Bot River Vlei", one of the largest lagoons in the south-western Cape of the Good Hope was opened to the sea by two artificial breachings of the sand bar which were aimed at lowering the excessively high water levels in the lagoon, and at the re-establishment of estuarine conditions. The Coastal Engineering and Hydraulics Division of the National Research Institute for Oceanology of the CSIR surveyed and monitored the hydrological and sedimentological events in the Bot River lagoon and at the mouth channels in an attempt to formulate a future viable management policy, which had to take into account the conflicting interests of the defenders of continued artificial breachings and of those who advocate conditions of a closed estuary which will eventually change into a coastal freshwater lake.

scholarly journals A Numerical Approach to Predict Water Levels in Ungauged Regions—Case Study of the Meghna River Estuary, Bangladesh

Water ◽  
2018 ◽  
Vol 10 (2) ◽  
pp. 110 ◽  
Author(s):  
Zakir Syed ◽  
Gyewoon Choi ◽  
Seongjoon Byeon
Keyword(s):  
River Estuary ◽  
Numerical Approach ◽  
Water Levels

scholarly journals Main trends in the dynamics of forest plantations in the buffer zone of the Novopolotsk Refinery Complex (based on the results of a 25-year research)

2020 ◽  
Vol 65 (1) ◽  
pp. 30-42
Author(s):  
I. P. Voznyachuk ◽  
A. A. Molozhavski ◽  
A. V. Sudnik ◽  
N. L. Voznyachuk
Keyword(s):  
Buffer Zone ◽  
Primary Forest ◽  
Leeward Side ◽  
Forest Fragments ◽  
Initial State ◽  
Plant Groups ◽  
Structure Of Communities ◽  
Composition And Structure ◽  
Ability To Regenerate ◽  
Spruce Stands

The unique results of the 25-year monitoring of forest vegetation of the buffer zone at the Novopolotsk Refinery Complex (NIRC) were summarized. The analysis of quantitative and qualitative changes in the buffer zone, which occurred during the period 1990–2015 years of operation of NRC’s enterprises, is given. Detailed analysis of vegetation organization has shown that the most transformed forest areas are directly adjacent to the enterprises from the leeward side. During the 25-year period of research, the area of primary forest fragments in the 500-meter zone of NRC impact has decreased by 2.6 times. Derivatives of small-leaved communities formed at the place of dead coniferous stands immediately after the commissioning of the plants are presented here. The technogenic press reduction in the 1990s resulted in the active demutation transformations of vegetation. Recently, there has also been a dominance of restoration processes, but the change of the main pine and spruce stands to derivatives continues, which is reflected in the prolonged decomposition of fragments of previously disturbed stands. The direction and rates of change of some plant groups by others depend on the initial state of plants, species and age structure of communities, conditions of their growth and environmental factors. In general, it is noted that forest ecosystems of the region have retained the ability to regenerate the composition and structure.

scholarly journals Benthic macroinvertebrate communities in sites with native forest presence and absence in north Patagonia

2020 ◽  
Vol 110 ◽  
Author(s):  
Patricio De los Ríos-Escalante ◽  
Carlos Esse ◽  
Rodrigo Santander-Massa ◽  
Pablo Saavedra ◽  
Francisco Encina-Montoya
Keyword(s):  
Species Composition ◽  
Neutral Theory ◽  
Null Model ◽  
Niche Overlap ◽  
Null Models ◽  
Species Number ◽  
Group Method ◽  
Native Forest ◽  
Macroinvertebrate Communities ◽  
Nothofagus Forests

ABSTRACT The benthic fauna in northern Patagonian streams is characterized by presence of water quality indicator species. The aim of the present study was characterized the benthic communities in streams associated to sites with presence of Nothofagus forests and with human intervention without Nothofagus forests using null models in ecology, unified neutral theory of biodiversity (UNTB) and unweighted pair group method with arithmetic mean (UPGMA). The results of species co-occurrence null model revealed that species associations are random, whereas the results of niche overlap null models revealed the presence of niche overlap. The UNTB results revealed low species number. The results of UPGMA revealed that species composition is specific for each site existing marked differences. The exposed results agree with results observed for central and northern Patagonian Chilean rivers, where the species composition is variable in according to surrounding basin properties and seasonal conditions.

scholarly journals Distribution of Polychaeta Communities in the Western and Northern Part of the Barents Sea

2020 ◽  
Author(s):  
Dinara Dikaeva ◽  
Elena Frolova
Keyword(s):  
Species Composition ◽  
Bottom Sediments ◽  
Barents Sea ◽  
Bottom Topography ◽  
Silty Clay ◽  
The Barents Sea ◽  
Structure Of Communities ◽  
Composition And Structure ◽  
Quantitative Characteristics ◽  
Hard Soils

Species composition and quantitative characteristics of polychaetes in the western and northern parts of the Barents Sea were analyzed on the basis of the material collected in July and November 2017 on MMBI expeditions aboard the RV “Dalniye Zelentsy”. Three faunistic polychaete complexes were revealed, depending on environmental conditions in the study area. A change in species composition and structure of communities from the bottom topography, structure of bottom sediments and bottom hydrodynamics were noted. An increase in biomass and density of polychaetes settlement was revealed in deep-water areas of the Barents Sea, on soft silty-clay soils, where the dominant species is Spiochaetopterus typicus. A decrease in quantitative characteristics of polychaetes was observed in shallow areas, on hard soils, in the zone of intensive erosion of bottom sediments as a result of warm and cold currents interaction, where the polychaete Nothria hyperborea dominated.

scholarly journals Composition and Structure of Aquatic Macroinvertebrate Communities in Mining Areas Streams (Côte d’Ivoire, West Africa)

2020 ◽  
Vol 3 (1) ◽  
pp. 15
Author(s):  
Ouattara Dongui Seniva ◽  
Tape Logboh David ◽  
Edia Oi Edia
Keyword(s):  
Ammonium Phosphate ◽  
Aquatic Environments ◽  
Ecological Indices ◽  
Macroinvertebrate Communities ◽  
Aquatic Macroinvertebrate ◽  
Whitney Test ◽  
Mining Areas ◽  
Mann Whitney Test ◽  
Composition And Structure ◽  
Aquatic Macroinvertebrate Communities

The existence of mining areas for decades could potentially affect aquatic environments and human health. This study allowed assessing the effects of mining activities on streams in three mining areas (Hiré, Lauzoua and Tortiya). Macroinvertebrates were collected on eight campaigns at eight stations using a hand-net, an Ekman grab and surber net. Environmental variables were recorded also. In this study the conductivity values were higher in the locality of Hiré. It was between 154.2 μS / cm (Tchindégri station) and 1753 μS / cm (Tributary Gbloh station). The highest temperature values were recorded in the stations of Tortiya locality (24 o C: Bou 2; 33.1 o C: Bou 1). A total of 184 taxa distributed among nine classes, 20 orders, 80 families and comprising 14 401 individuals were recorded. Insecta were the most diversified class in macroinvertebrate community (84% of taxa collected, eight orders and 59 families). Ecological indices (Shannon Weiner, rarefied richness, Pielou’s evenness) were significantly low at Lauzoua (N'Téko station) and Hiré (Tributary Gbloh station) (Mann- Whitney test, P <0.05). Ecological indices showed no significant variation between the stations of the locality of Tortiya. The PCA had grouped the stations into four clusters. Conductivity, ammonium, phosphate, nitrites, and nitrates were significantly higher (Mann- Whitney test, P < 0.05) in cluster I (Tributary Gbloh station) Compared to other clusters. Eight taxa (Limnius sp., Liberonautes chaperi, Gordius sp., Phyllogomphus sp., Orectogyrus sp., Bezzia sp., Adenophlebiodes, Parasedodes sp.) were specific to Tchindégri station (Hiré) and six taxa (Naucoris sp., Amphiops sp., Hydrobius sp., Pseudobagous longulus, Culicinae and Gomphus sp.) were associated to the Bou 1 and Bou 2 stations (Tortiya).

Sign in / Sign up

Export Citation Format

Share Document