The river siltingis usually solved by dredging the sediment deposited in its bed, employing many techniques. In dealing with a concrete case, the objective is to expose the technical criteria lack for the execution of such intervention, the impacts to the river, aquatic biota and its real need. Here aspects of the dissociation between consecrated understandings in the engineering and their mismatch with the ecological theories are presented. This work aimed to study urban floods, elucidating their causes, to propose measures and new technologies to deal with them, through programs and urban policies. The intention is to detail the causes of urban floods, understanding the factors involved and with that, discuss how the public power should proceed in what refers to the dredging. The main objective of this work is to stimulate the incorporation of urban rivers into ecological studies and to draw public attention to this issue.
ABSTRACT. Study of the natural diet of the fish fauna of a centenary reservoir, São Paulo, Brazil. This study aimed characterize and compare the fish feeding from 13 fish species in three areas (river influence zone, transition zone and lake area) of Itupararanga reservoir. We analyzed 436 stomach, were found 17 food resources, all of autochthonous origin. The predominant species diet were: fish, insect, plant material and debris in the river influence zone; fish, sediment and plant material in the transition zone and insects, fish and scales in the lacustrine zone. The diet was characterized by Feeding Index (IA). Species were categorized in guilds: piscivorous insectivores, detritivores and carcinofagous. The Cluster indicated separation of insectivorous guild in generalist species (insects) and specialized (Chironomidae) which increases to five guilds. In the riverine zone area were found four guilds; in the transition zone three guilds and lacustrine zone two guilds. There was still a dominance of piscivorous species may be related to the age of the reservoir. This study expanded knowledge about fish feeding habits in old reservoirs and their differences comparing existing zones. KEYWORDS.Guilds, old reservoir, resources origin, Sorocaba river, Itupararanga reservoir. RESUMO.Este estudo teve como objetivo caracterizar e comparar a alimentação de 13 espécies de peixes em três zonas (zona de influência fluvial, zona de transição e zona lacustre) do reservatório de Itupararanga. Foram analisados 436 estômagos, sendo encontrados 17 recursos alimentares, todos de origem autóctone. As dietas predominantes das espécies foram: peixe, inseto, material vegetal e detritos na zona de influência fluvial, peixe, sedimento e material vegetal na zona de transição e inseto, escama e peixe na zona lacustre. Através do Índice Alimentar, as espécies foram categorizadas nas guildas: piscívora, insetívora, detritívora e carcinófaga. O Cluster indicou separação da guilda insetívora em espécies generalistas (insetos diversos) e especialista (Chironomidae) o que aumenta para cinco guildas. Na zona fluvial foram verificadas quatro guildas; na zona de transição três guildas e na zona lacustre duas guildas. Observou-se ainda uma dominância de espécies piscívoras que pode estar relacionada à idade do reservatório. Este estudo ampliou o conhecimento dos hábitos alimentares dos peixes em reservatórios antigos e suas diferenças, comparando as zonas existentes. PALAVRAS-CHAVE.Guildas, reservatório antigo, origem recursos, rio Sorocaba, reservatório de Itupararanga.
Abstract:The Floresta Nacional de Ipanema is located on the southeast of the state of São Paulo, Brazil, and belongs to the cities of Araçoiaba da Serra, Iperó and Capela do Alto. It extends over an area of 5,069 ha surrounded by several streams, small lakes, the Ipanema river and the Hedberg dam. The fish species in this area were sampled between 1993 and 2012 in several isolated studies, with the use of gill nets and sieves. Fifty species of fish were registered, 43 native and 7 non-native (Cyprinus carpio, Piaractus mesopotamicus, Brycon cephalus, Triportheus nematurus, Clarias gariepinus, Tilapia rendalli and Poecilia vivipara), distributed in seven Orders, 21 Families and 41 Genera. The present study aimed at cataloguing the fish species in the Ipanema National Forest. Handling and preservation actions will be based on the information obtained.
The present study aimed to create an inventory of non-native fish species in the basin of the Sorocaba river, located at Upper Rio Paraná. Fish were collected between August 2010 and January 2012 using nets with meshes, round shaped fishing nets, hand net and electric fishing equipment, as well as contacts with fishermen to seek information on species captured in the basin. Besides, we used published data and information contained in reports, monographs and thesis. Five non-native fish species were collected: Tilapia rendalli, Oreochromis niloticus, Pterygoplichthys anisitsi, Poecilia vivipara and Triportheus nematurus that represented 10.63% of all fish species captured in the basin of the Sorocaba river. The occurrence of eight other species, although they were not collected by the sampling program of this study, had already been reported in previous studies, and had already been captured by amateur and professional fishermen, particularly in the reservoir of Itupararanga and in the urban stretch of the Sorocaba river.
The Neotropical region hosts 4225 freshwater fish species, ranking first among the world's most diverse regions for freshwater fishes. Our NEOTROPICAL FRESHWATER FISHES data set is the first to produce a large‐scale Neotropical freshwater fish inventory, covering the entire Neotropical region from Mexico and the Caribbean in the north to the southern limits in Argentina, Paraguay, Chile, and Uruguay. We compiled 185,787 distribution records, with unique georeferenced coordinates, for the 4225 species, represented by occurrence and abundance data. The number of species for the most numerous orders are as follows: Characiformes (1289), Siluriformes (1384), Cichliformes (354), Cyprinodontiformes (245), and Gymnotiformes (135). The most recorded species was the characid Astyanax fasciatus (4696 records). We registered 116,802 distribution records for native species, compared to 1802 distribution records for nonnative species. The main aim of the NEOTROPICAL FRESHWATER FISHES data set was to make these occurrence and abundance data accessible for international researchers to develop ecological and macroecological studies, from local to regional scales, with focal fish species, families, or orders. We anticipate that the NEOTROPICAL FRESHWATER FISHES data set will be valuable for studies on a wide range of ecological processes, such as trophic cascades, fishery pressure, the effects of habitat loss and fragmentation, and the impacts of species invasion and climate change. There are no copyright restrictions on the data, and please cite this data paper when using the data in publications.
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