Consulta: subjectFacets:"Aquatic ecosystems"
Registros recuperados: 8
Data/hora: 13/06/2024 03:55:48

Sustaining Aquatic Ecosystems in Boreal Regions
Provedor de dados: 7
Autores: Schindler, David; University of Alberta; d.schindler@ualberta.ca.
Few boreal waters are managed in a sustainable manner, because cumulative effects of a variety of human activities are not considered. Fisheries and water quality have declined in most large water bodies of the southern boreal zone. Some of the reasons are direct, including overexploitation of fisheries, alteration of flow patterns, introductions of non-native species, and discharge of eutrophying nutrients and persistent contaminants. However, improper management of watersheds and airsheds also causes degradation of aquatic ecosystems. Clear-cut logging, climatic warming, acid precipitation, and stratospheric ozone depletion are among the more important of these indirect stressors. There are important interactions among these stressors, requiring that...
Tipo: Peer-Reviewed Reports
Palavras-chave: Atmospheric stressors; Aquatic ecosystems; Biodiversity of streams and lakes; Boreal ecosystems; Clear-cutting; Cumulative effects; Ecological invasions; Fisheries; Indigenous peoples; Land-water interactions; Sustainable development; Watershed management.
Ano: 1998

Ecological History vs. Social Expectations: Managing Aquatic Ecosystems
Provedor de dados: 7
Autores: Reeves, Gordon H.; USDA Forest Service, Pacific Northwest Research Station; greeves@fs.fed.us; Duncan, Sally L.; Institute of Natural Resources, Oregon State University; Sally.Duncan@oregonstate.edu.
The emerging perspective of ecosystems as both non-equilibrium and dynamic fits aquatic ecosystems as well as terrestrial systems. It is increasingly recognized that watersheds historically passed through different conditions over time. Habitat conditions varied in quantity and quality, primarily as a function of the time since the last major disturbance and the legacy of that disturbance. Thus, to match the effects of historical processes, we would expect a variety of conditions to exist across the watersheds in a region at any time. Additionally, watersheds have different potentials to provide habitat for given fish species because of variation in physical features. This developing ecological understanding is often preempted by social desires to bring...
Tipo: Peer-Reviewed Reports
Palavras-chave: Aquatic ecosystems; Legacy of disturbance; Non-equilibrium ecosystem dynamics.
Ano: 2009

Relatório técnico: pulso de inundação, diversidade e biologia dos peixes na Baía do Tuiuiú, Pantanal Sul.
Provedor de dados: 14
Autores: RESENDE, E. K. de; SALIS, S. M. de; ISHII, I. H.; SANTOS, R. A. C. P.; MOURA, H. C. G. de; MONACO, I. de A.; FERREIRA, L. K. S. G.; SILVA, L. W. da.
O Pantanal é conhecido pela sua riqueza ictiofaunística e constitui região de pesca visitada por muitos pescadores esportivos. Mas o que faz com que esse tipo de ambiente inundável seja tão rico em peixes? Esse artigo se propõe a responder a essa questão, mostrando que o pulso de inundação, o encher e secar a cada ano, típico de ambientes inundáveis, é o processo ecológico que regula sua fauna e flora, particularmente os peixes. Para tanto foi escolhido um braço abandonado do Rio Paraguai, denominado localmente como Baía do Tuiuiú, onde se estudou o ambiente, em termos de vegetação circundante, as características limnológicas de suas águas e suas relações com os peixes ocorrentes em termos de composição, riqueza, diversidade e suas estratégias de vida.
Tipo: Documentos (INFOTECA-E)
Palavras-chave: Pulso de inundação; Peixe; Inundação; Ecologia aquática; Fish; Floods; Aquatic ecosystems.
Ano: 2016
URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/1053104

Divergence in energy sources for Prochilodus lineatus (Characiformes: Prochilodontidae) in Neotropical floodplains
Provedor de dados: 83
Autores: Benedito,Evanilde; Santana,Ana Rute A.; Werth,Martin.
ABSTRACT The stable carbon isotopic variability and the contributions of autochthonous (sediment microbial biomass, phytoplankton, and periphyton) and allochthonous (soil microbial biomass) sources available to the detritivorous fish Prochilodus lineatus were investigated in three environments of the floodplain of the Upper Paraná River. The isotopic composition of carbon sources and fish varied significantly among the studied environments. The autochthonous resources, represented by the phytoplankton, were the most assimilated by the species, followed by periphyton and sediment microbial biomass. The species used the sources differently in each environment. This study suggests that the inherent characteristics of this area, as well as the size of the...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Aquatic ecosystems; Carbon sources; Fish; Organic matter; Stable isotopes.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252018000400204

STATUS OF THE INVASION OF A POACEAE SPECIES IN TROPICAL SEMIARID RESERVOIRS
Provedor de dados: 87
Autores: ALVES,R.M.A.; ALBUQUERQUE,M.B.; BARBOSA,L.G.
ABSTRACT The species of the Urochloa genus, exotic and infesting in Brazilian waters, are known to be invasive and dominant, occupying from humid, shallow areas, and irrigation canals to margins of deep reservoirs. This paper hypothesis that less depth reservoirs have higher infestation rate and higher biomass of U. arrecta. The objectives were to measure the percentage of occurrence of exotic macrophyte U. arrecta in 40 ecosystems from the Mamanguape basin (Paraíba, Brazil) and determine the infestation of the species in two reservoirs. The acquired data were geo-referenced with the ArcGIS software (v. 9.3). A covariance analysis was performed using the R program (The R project is Statistical Computing). The results showed large spatial distribution of...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Urochloa arrecta; Aquatic ecosystems; Spatial scales.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582017000100231

Assessment of the ecological functionality of anthropogenically created habitats in the impoundment of the hydropower plant Freudenau (Vienna, Austria) with bi- and multivariate statistical analyses
Provedor de dados: 103
Autores: Tarkus,Martin; Volkmann,Christian; Drexler,Silke-Silvia; Waidbacher,Herwig; Straif,Michael.
The construction of the hydropower plant Freudenau was accompanied by the introduction of new structures and habitats. This study processes and evaluates the ecological fish data for the periods 1999/2000 and 2003/2004. The area was subdivided into five sections and 19 habitats (stream kilometer 1914.50 to 1994.60). Bi- and multivariate analyses were inducted with SPSS© (SPSS 2007). The CPUE values show that most fish remain in the Transition Zone and in the Head of Reservoir. The cluster analyses of the individual habitats show that these can be characterized primarily by abiotic factors. There was a strong statistical relationship between the individual habitats and the Danube mainstream. We conclude that fish have access to the habitats and that there...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Aquatic ecosystems; Fish ecology; Hydraulic engineering; River management.
Ano: 2010
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1984-46702010000100014

Scientometric analysis of energetic ecology: primary production of aquatic macrophytes - DOI: 10.4025/actascibiolsci.v31i4.5139
Provedor de dados: 3
Autores: Lolis, Solange de Fátima; Fundação Universidade Federal do Tocantins; Sanches-Marques, Angela Maria Marques; UEM; Arruda Reis, Sebastiana Lindaura; UFMT; Benedito, Evanilde; UEM.
The objective of this work was to perform a temporal quantitative analysis, using the scientometric technique, considering the number of citations that the terms Primary Production of Aquatic Macrophytesand  Energetic Ecology received in a 50-year period (1956 to 2006). The study related 189 papers published in 26 magazines. It was verified that researchers of several nationalities are working on the proposed themes, with a predominance of those from developed countries (USA and Germany). In Brazil, production on these themes, although small, coincides with the results obtained for other themes analyzed using the same research technique. This fact indicates that greater efforts should be made in the search for more intense scientific production in the...
Palavras-chave: 2.00.00.00-6    Ciências Biológicas energy flow; Aquatic macrophytes; Aquatic ecosystems; Primary producers; Scientific production Ecologia.
Ano: 2009
URL: http://periodicos.uem.br/ojs/index.php/ActaSciBiolSci/article/view/5139

Eco-genetic study on water hyacinth, Eichhornia crassipes (Mart.) Solms, the world's most invasive aquatic plant
Provedor de dados: 111
Autores: El-Shahawy, Tarek Abd El-Ghafar.
Water hyacinth is a complicated, multifaceted problem disturbs all interested and concerned entities in aquatic weed management. Water hyacinth, which is the world's most aggressive and destructive aquatic freshwater species, extends over vast areas of the world creating serious ecological and cultural problems. So far, water quality does not represent a dilemma against water hyacinth growth. The objective of the current work is to study the potential genetic differences between water hyacinth populations growing under different aquatic ecosystems in Egypt. Water and plant samples were collected from three different sites namely irrigation water, drainage water and sewage water at Al-Buhayrah Governorate, Damanhour District. The physicochemical properties...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Botany; Weed biology and control Aquatic weeds; Aquatic ecosystems; Genetic variation; Heavy metals; Invasive plants; Water quality.
Ano: 2018
URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/4392