The role of fishery management and environmental variables on the fish fauna in floodplain lakes in the lower Purus River, Amazon Basin, Brazil

2021 ◽  
Vol 26 (4) ◽  
Author(s):  
Bruno Ferezim Morales ◽  
Cláudia Pereira de Deus
Keyword(s):  
Environmental Variables ◽  
Amazon Basin ◽  
Fishery Management ◽  
Fish Fauna ◽  
Floodplain Lakes

scholarly journals Effect of waterfalls and the flood pulse on the structure of fish assemblages of the middle Xingu River in the eastern Amazon basin

2015 ◽  
Vol 75 (3 suppl 1) ◽  
pp. 78-94 ◽  
Author(s):  
TAP Barbosa ◽  
NL Benone ◽  
TOR Begot ◽  
A Gonçalves ◽  
L Sousa ◽  
...  
Keyword(s):  
Amazon Basin ◽  
Fish Assemblages ◽  
Fish Fauna ◽  
Flood Pulse ◽  
Total Dissolved Solids ◽  
Total Suspended Matter ◽  
Xingu River ◽  
Temporal Factors ◽  
Principal Factors

Abstract The structure of fish assemblages in Neotropical rivers is influenced by a series of environmental, spatial and/or temporal factors, given that different species will occupy the habitats that present the most favourable conditions to their survival. The present study aims to identify the principal factors responsible for the structuring of the fish assemblages found in the middle Xingu River, examining the influence of environmental, spatial, and temporal factors, in addition to the presence of natural barriers (waterfalls). For this, data were collected every three months between July 2012 and April 2013, using gillnets of different sizes and meshes. In addition to biotic data, 17 environmental variables were measured. A total of 8,485 fish specimens were collected during the study, representing 188 species. Total dissolved solids, conductivity, total suspended matter, and dissolved oxygen concentrations were the variables that had the greatest influence on the characteristics of the fish fauna of the middle Xingu. Only the barriers and hydrological periods played a significant deterministic role, resulting in both longitudinal and lateral gradients. This emphasizes the role of the connectivity of the different habitats found within the study area in the structuring of its fish assemblages.

scholarly journals Second floor, please: the fish fauna of floating litter banks in Amazonian streams and rivers

2013 ◽  
Vol 11 (1) ◽  
pp. 85-94 ◽  
Author(s):  
Lucelia Nobre Carvalho ◽  
Luana Fidelis ◽  
Rafael Arruda ◽  
Andre Galuch ◽  
Jansen Zuanon
Keyword(s):  
Species Richness ◽  
Fish Assemblage ◽  
Amazon Basin ◽  
Stream Water ◽  
Fish Fauna ◽  
Assemblage Composition ◽  
Plant Matter ◽  
Carnivorous Species ◽  
Ephemeral Habitat ◽  
Dead Plant

Floating litter banks are an ephemeral habitat consisting of branches, twigs, flowers, seeds, and fruits that are trapped on the stream water surface by a variety of retention mechanisms. These heterogeneous materials form a deep layer of dead plant matter that is colonized by a variety of organisms, including fish that forage on the aquatic macroinvertebrates found in this unique habitat. In this study, we aimed to characterize which fish species occupy the floating litter banks and their trophic characteristics, as well as determine if fish assemblage composition and species richness can be predicted by the size of the floating litter banks. Fish sampling was conducted in five rivers located in the Amazon basin. Of the 31 floating litter banks sampled that contained fish, 455 individuals were recorded and were distributed within 40 species, 15 families and five orders. Siluriformes were the most representative order among the samples and contained the largest number of families and species. The fish fauna sampled was mainly composed of carnivorous species that are typically found in submerged litter banks of Amazonian streams. The fish assemblage composition in the kinon can be predicted by the volume of the floating litter banks using both presence/absence and abundance data, but not its species richness. In conclusion, kinon banks harbor a rich fish assemblage that utilizes this habitat for shelter and feeding, and may function as a refuge for the fishes during the peak of the flooding season.

scholarly journals Monitoring studies should consider temporal variability to reveal relations between cyanobacterial abundance and environmental variables

2015 ◽  
Vol 87 (3) ◽  
pp. 1717-1726 ◽  
Author(s):  
JULIANA WOJCIECHOWSKI ◽  
ANDRÉ A. PADIAL
Keyword(s):  
Temporal Variability ◽  
Environmental Variables ◽  
Environmental Changes ◽  
Environmental Variability ◽  
Time Lag ◽  
Cyanobacteria Blooms ◽  
Environment Variables ◽  
Sampling Points ◽  
The Relationship

One of the main goals of monitoring cyanobacteria blooms in aquatic environments is to reveal the relationship between cyanobacterial abundance and environmental variables. Studies typically correlate data that were simultaneously sampled. However, samplings occur sparsely over time and may not reveal the short-term responses of cyanobacterial abundance to environmental changes. In this study, we tested the hypothesis that stronger cyanobacteria x environment relationships in monitoring are found when the temporal variability of sampling points is incorporated in the statistical analyses. To this end, we investigated relationships between cyanobacteria and seven environmental variables that were sampled twice yearly for three years across 11 reservoirs, and data from an intensive monitoring in one of these reservoirs. Poor correlations were obtained when correlating data simultaneously sampled. In fact, the 'highly recurrent' role of phosphorus in cyanobacteria blooms is not properly observed in all sampling periods. On the other hand, the strongest correlation values for the total phosphorus x cyanobacteria relationship were observed when we used the variation of sampling points. We have also shown that environment variables better explain cyanobacteria when a time lag is considered. We conclude that, in cyanobacteria monitoring, the best approach to reveal determinants of cyanobacteria blooms is to consider environmental variability.

scholarly journals Ichthyofauna of streams from the lower Iguaçu River basin, Paraná State, Brazil

2016 ◽  
Vol 16 (3) ◽  
Author(s):  
Crislei Larentis ◽  
Rosilene Luciana Delariva ◽  
Louise Cristina Gomes ◽  
Dirceu Baumgartner ◽  
Igor Paiva Ramos ◽  
...  
Keyword(s):  
River Basin ◽  
Fish Fauna ◽  
Main Channel ◽  
Indicator Species Analysis ◽  
Irreversible Loss ◽  
Species Analysis ◽  
Geomorphological Processes ◽  
Nmds Analysis ◽  
Iguaçu River

Abstract The drainages of the Iguaçu River basin, as well as the main channel of the river, have peculiar characteristics resulting from geomorphological processes in this area, including the formation of the Iguaçu River Falls. This slope in the lower portion of the basin is a biogeographical barrier to many organisms. In this study was inventoried the fish fauna of streams of the lower Iguaçu River basin, evaluating possible differences in the species composition upstream and downstream of this biogeographical barrier. Sampling were conducted between 2004 and 2013, in five streams, three upstream and two downstream of the Iguaçu River Falls, using electrofishing. The nMDS analysis was run to investigate possible groupings of similar fauna between the streams sampled. The scores of this test were tested as to the significance of groupings with the Hotelling T2 test. The indicator value method (IndVal) was used to detect the distribution of species among the groups of the streams upstream and downstream of the Iguaçu River Falls. We collected 18,908 individuals of six orders, 11 families, and 40 species. Siluriformes and Characiformes had the highest species richness; Cyprinodontiformes presented the highest abundance. Considering the species recorded, 21 are considered natives to the Iguaçu River basin, including 15 endemic, wich were found only in streams upstream of the falls. Additional 18 species were verified only in the streams downstream of such barrier. Four species were common to both stretches. The axis 1 of the nMDS separated two groups: streams upstream (S1, S2 and S3) and streams downstream of the Iguaçu River Falls (S4 and S5). The indicator species analysis also indicated a distinction between the groups of streams, that were significantly different (Hotelling's T2 = 234.36, p ˂ 0.0001). The number of endemic species in the streams upstream of the Falls (15 spp.) evidences a significant effect of isolation promoted by the Iguaçu River Falls, and confirms the role of this barrier in the vicariant processes and endemism typical of this basin. These results emphasize the importance of conserving these ecosystems, once the extinction of species in this region means the irreversible loss of them.

scholarly journals The role of fishery supervisors and community participation to ensure the sustainable fisheries in Indonesia’s Exclusive Economic Zone

2021 ◽  
Vol 890 (1) ◽  
pp. 012068
Author(s):  
Maskun ◽  
H Assidiq ◽  
S N Bachril ◽  
N Al-Mukarramah
Keyword(s):  
Community Participation ◽  
Fishery Management ◽  
Exclusive Economic Zone ◽  
Law Of The Sea ◽  
Fish Resources ◽  
Effective Manner ◽  
Economic Zone ◽  
The Law ◽  
The Right

Abstract Indonesia has ratified the United Convention Law of the Sea of 1982 with the Law No. 17 of 1985 concerning the Ratification of United Nations Convention on The Law of the Sea 1982. It means that Indonesia has the right to use, conserve, and manage fish resources in the Indonesia’s Exclusive Economic Zone (IEEZ). To guarantee the optimal and sustainable management of Indonesian fish resources, the role of fishery supervisors and community participation in an efficient and effective manner is needed. Law enforcement in the field of fisheries is very important and strategic to support fishery development in accordance with the principle of fishery management, so that the sustainable development of fisheries can be done continuously. Therefore, the existence of legal certainty is absolutely necessary to support fishery management in Indonesia.

scholarly journals Ecological interrelations of Rapana venosa (Gastropoda: Muricidae) with ichthyofauna in the Black Sea

2016 ◽  
Vol 1 (4) ◽  
pp. 76-77
Author(s):  
I. P. Bondarev
Keyword(s):  
Black Sea ◽  
Marine Ecosystem ◽  
Fish Fauna ◽  
The Black Sea ◽  
Sandy Bottom ◽  
Rapana Venosa ◽  
New Information ◽  
Bottom Zone

Systematic monitoring of ecologically significant species – predatory mollusc Rapana venosa Valenciennes, 1846 populations – is an important part of the Black Sea monitoring. The study of the role of R. venosa in contemporary marine ecosystem is of considerable interest. In June-September 2015-2016 the study of consorting relations of rapana was conducted in situ with a parallel sampling by diver. In the course of research new information about the interaction of R. venosa with the fish fauna has been obtained. Of particular importance for fishes is the presence of rapana in the sandy bottom zone, where there are no natural shelters, and food resources are limited. The most important for the fish is the presence on the rapana shells of algal fouling and epiphyton. The shells of invader – R. venosa – and its fouling create additional opportunities for the survival of some fish fauna representatives juveniles of the Black Sea. The data obtained extend the concepts of ecological role of mollusc – invader R. venosa, as well as the ecology and ethology of several fish species.

scholarly journals Detecting environment-dependent diversification from phylogenies: a simulation study and some empirical illustrations

2017 ◽  
Author(s):  
Eric Lewitus ◽  
Hélène Morlon
Keyword(s):  
Environmental Variables ◽  
Relative Importance ◽  
Species Trees ◽  
Major Goal ◽  
Explanatory Variables ◽  
Extinction Rates ◽  
Dependency Tree ◽  
Species Evolution ◽  
Abiotic Variables

AbstractUnderstanding the relative influence of various abiotic and biotic variables on diversification dynamics is a major goal of macroevolutionary studies. Recently, phylogenetic approaches have been developed that make it possible to estimate the role of various environmental variables on diversification using time-calibrated species trees, paleoenvironmental data, and maximum-likelihood techniques. These approaches have been effectively employed to estimate how speciation and extinction rates vary with key abiotic variables, such as temperature and sea level, and we can anticipate that they will be increasingly used in the future. Here we compile a series of biotic and abiotic paleodatasets that can be used as explanatory variables in these models and use simulations to assess the statistical properties of the approach when applied to these paleodatasets. We demonstrate that environment-dependent models perform well in recovering environment-dependent speciation and extinction parameters, as well as in correctly identifying the simulated environmental model when speciation isenvironment-dependent. We explore how the strength of the environment-dependency, tree size, missing taxa, and characteristics of the paleoenvironmental curves influence the performance of the models. Finally, using these models, we infer environment-dependent diversification in three empirical phylogenies: temperature-dependence in Cetacea,δ13C-dependence in Ruminantia, andCO2-dependence in Portulacaceae. We illustrate how to evaluate the relative importance of abiotic and biotic variables in these three clades and interpret these results in light of macroevolutionary hypotheses for mammals and plants. Given the important role paleoenvironments are presumed to have played in species evolution, our statistical assessment of how environment-dependent models behave is crucial for their utility in macroevolutionary analysis.

scholarly journals Accounting and disciplinary methods in fishery management

2021 ◽  
Vol 34 (9) ◽  
pp. 218-249
Author(s):  
Stefania Servalli ◽  
Antonio Gitto
Keyword(s):  
Fishery Management ◽  
18Th Century ◽  
The State ◽  
Fish Stock ◽  
Control Mechanisms ◽  
Local Authorities ◽  
Local Conditions ◽  
Content Type ◽  
Papal States

PurposeThe purpose of this study is to contribute to the research related to “the interplay between accounting and the state, politics, and local authorities in the broad government and administration of food for sustainability of populations” (Sargiacomo et al., 2016). Considering contemporary examples and investigating the genealogy of an 18th-century reform of fishery management (the New Plan), the authors explore the role played by accounting and calculative practices when local authorities intervene using forms of discipline based on control systems that acted on commons (fish), people and space.Design/methodology/approachThis paper is historically grounded on archival research on a fish provisioning case during the 18th century in Ancona, an Italian town on the Adriatic coast. The investigation adopts an approach focussed on the use of disciplinary methods in the terms highlighted by Foucault. This perspective offers a lens capable of revealing the key role of accounting in a period when discipline became “general formulas of domination” (Foucault, 1977) and the Papal States were looking for food provisioning solutions (Foucault, 2007). The study highlights similarities with contemporary fishery management.FindingsThe paper shows that governability of fishery in a commons' logic is not limited by the properties of the good, but rather “it is achieved through the objects and instruments that are deployed to make it possible” (Johnsen, 2014, p. 429). It reveals forms assumed by economic calculation in different eras and their contribution in the art of governing realised by the state (Hoskin and Macve, 2016). The study unveils how accounting effectively operates using “naming and counting” activities (Ezzamel and Hoskin, 2002) based on a system of documents and accounting registers; these have a pivotal role in redefining fishery management and in keeping goods (fish) and people (fishermen) under control. The investigation also highlights the importance of properly quantifying data in fishery management, confirming the literature on the topic (Beddington et al., 2007, p. 1713). In contemporary situations, data refer to quantifying the fish stock in the sea and the consequent estimation of fish catch. In the historical investigation, although environmental protection was not an issue, quantification refers to the fish that entered the town of Ancona, whose estimation was the result of a new calculative approach adopted by local authorities facing fish needs. In addition, it offers early evidence of organised and rational-based control mechanisms that were the result of Enlightened ideas emerging in the Papal States context.Originality/valueDespite the fact that fish represent a fundamental good for governments to act on in response to a population's needs, there has been no attention paid to how governmental authorities have used disciplinary mechanisms to intervene in fishery management or the role played by accounting. This study's novelty is its investigation of fishery, using Foucauldian disciplinary methods to understand accounting's contribution in fishery governance. In addition, this investigation permits to unveil the role of accounting to support one of the main principles of the governance of commons that is represented by the congruence between rules and local conditions (Fennell, 2011, p. 11; Ostrom, 1990, p. 92).

scholarly journals The role of environmental variables onAedes albopictusbiology and chikungunya epidemiology

2013 ◽  
Vol 107 (5) ◽  
pp. 224-241 ◽  
Author(s):  
Joanna Waldock ◽  
Nastassya L. Chandra ◽  
Jos Lelieveld ◽  
Yiannis Proestos ◽  
Edwin Michael ◽  
...  
Keyword(s):  
Environmental Variables
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