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Registros recuperados: 119 | |
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Meire, P.. |
Habitat verlies en degradatie is één van de belangrijke ecologische problemen van deze eeuw. Hoewel alle ecosystemen hieronder te lijden hebben, blijken wetlands of waterrijke gebieden, op wereldschaal vrij zeldzame gebieden, onder zeer zware antropogene druk te staan. Het is daarom ook niet te verwonderen dat deze ecosystemen sinds meerdere jaren een belangrijke prioriteit vormen voor het natuurbehoud. Binnen de wetlands vormen estuaria zeer produktieve systemen waarvan het rijke voedselaanbod wordt benut door grote aantallen steltlopers, die buiten het broedseizoen bijna volledig op dergelijke getijdengebieden zijn aangewezen. Het belang van het Deltagebied (NI.) en met name de getijdengebieden van Ooster- en Westerschelde voor watervogels worden kort... |
Tipo: Info:eu-repo/semantics/doctoralThesis |
Palavras-chave: Benthos; Birds; Estuaries; River; Water. |
Ano: 1993 |
URL: http://www.vliz.be/imisdocs/publications/5961.pdf |
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Anjos,Luiz dos; Graf,Vinalto. |
Two hundred and eighty eight bird species were registered in Santa Rita Farm, east of Paraná State in Brazil (28º18'S,49º48'W), from February 1990 to January 1991. Eighty four species were registered in all 12 months and eighty three were registered once during this period. October was the richest in number of species (220) and July was the poorest (137). The natural landscape of the Santa Rita farm is composed of open field with several patches of araucaria forest (from 10 to 40 ha) and some small areas of marshland. Two hundred and eight species occurred only in one of these habitats: 163 in the forest, 35 in the open field and 10 in the marshland. The others often occurred in both forest and open field; there is a gradient of occurrence between them.... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Birds; Richness; Distribution; Paraná; Brazil. |
Ano: 1993 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-81751993000400013 |
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Ribeiro,Maria das Graças; Teles,Maria Eloiza de Oliveira; Maruch,Sandra Maria das Graças. |
The study of the female genital system of Columba livia (Gmelin, 1789) is part of the research on the reproductive biology of Brazilian birds. This work describes the morphological aspects of the ovary of Columba livia, as well as the histological differences observed in the ovarian follicles during the ovocyte maturation process. Ten Columba livia females were studied, whose ovaries had been dissected, fixed in Bouin and Helly solutions, and histologically processed for staining (Hematoxylin-Eosin; Gomori's trichromic and Weigert's technique and Gomori's technique for connective tissue fibers). The ovary has an irregular surface, is located in the abdominal cavity, and relates to the cranial portion of the left kidney and caudal extremity of the left... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Columbidae; Birds; Genital apparatus; Ovary. |
Ano: 1995 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-81751995000100016 |
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Maruch,Sandra Maria das Graças; Teles,Maria Eloiza de Oliveira; Ribeiro,Maria das Graças. |
Known as "domestic dove", the Columba livia (Gmelin, 1789) is a columbidae species widely distributed in Brazil, whose reproductive biology has been studied by many researchers. The testes of 12 Columba livia males were collected and prepared for histologic examination under an optical microscope, the results of which were analysed and photographed. The tunica albuginea that covers the testes consists of a thick, not very cellular layer of dense connective tissue. Groups of interstitial cells with typical morphological appearance and surrounded by loose, well vascularized connective tissue are observable within the organ, between the seminiferous tubules. The seminiferous tubules are thick, intensely wound and, when seen in cross section, show Sertoli... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Columbidae; Birds; Genital apparatus; Testis. |
Ano: 1995 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-81751995000100015 |
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Vicente,J. Júlio; Pinto,R. Magalhães; Noronha,Dely; Carvalho,Patrícia Goulart de. |
This report deals with the identification of one hundred and seventy-one samples of nematodes recovered from Brazilian birds collected by Lauro Travassos and his staff, between 1921-1960. Aprocta travassossi Caballero, 1938, Aprocta sp., Baruscapillaria appendiculata (Freitas, 1933) Moravec, 1982, Contracaecum plagiaticium Lent & Freitas, 1948, C. spiculigerum (Rudolphi, 1809) Railliet & Henry, 1912, Contracaecum sp., Cyrnea (C.) semilunaris (Molin, 1860) Seurat, 1914, Oxyspirura sp., Paronchocerca ibanezi (Freitas, Vicente & Pinto, 1970) Anderson &. Bain, 1976, Porrocaecum sp., Procyrnea sp., Skrjabinura spiralis Gnédina, 1933, Subulura acutissima Molin, 1860, S. bentocruzi Barreto, 1919, S. travassossi Barreto, 1919, Subulura... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Nematodes; Pelecaniformes; Trogoniformes; Birds; Brazil. |
Ano: 1996 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-81751996000400011 |
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Reinert,Bianca L; Pinto,Júlio C; Bornschein,Marcos R; Pichorim,Mauro; Marini,Miguel Â. |
Five hundred and eigh body masses of 74 forest birds, and measurements of wing, tail, tarsus and beak of 14 poorly known species mist-netted at two sites in the Atlantic Forest of eastern Paraná State, southern Brazil, are presented. |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Birds; Body masses; Measurements; Atlantic Forest. |
Ano: 1996 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-81751996000400001 |
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Niemi, Gerald; University of Minnesota; gniemi@d.umn.edu; Hanowski, JoAnn; University of Minnesota; jhanowsk@sage.nrri.umn.edu; Helle, Pekka; Finnish Game and Fisheries Research Institute; meltausrta@HELSINKI.RKTL.fi; Howe, Robert; University of Wisconsin; hower@uwgb.wi.edu; Venier, Lisa; Canadian Forest Service; lvenier@nrcan.gc.ca; Welsh, Daniel; Canadian Forest Service; dwelsh@AM.NCR.FORESTRY.CA. |
We review characteristics of birds in boreal forests in the context of their ecological sustainability under both natural and anthropogenic disturbances. We identify the underlying ecological factors associated with boreal bird populations and their variability, review the interactions between boreal bird populations and disturbance, and describe some tools on how boreal bird populations may be conserved in the future. The boreal system has historically been an area with extensive disturbance such as fire, insect outbreaks, and wind. In addition, the boreal system is vulnerable to global climate change as well as increasing pressure on forest and water resources. Current knowledge indicates that birds play an important role in boreal forests, and... |
Tipo: Peer-Reviewed Reports |
Palavras-chave: Birds; Boreal; Conservation; Disturbance; Forests; Forestry; Natural resources; Nearctic; Palearctic; Sustainability; Trends.. |
Ano: 1998 |
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Sutherland, Glenn D; University of British Columbia; gsland@interchg.ubc.ca; Harestad, Alton S; Simon Fraser University; harestad@sfu.ca; Price, Karen; Simon Fraser University; kprice@futurenet.ca; Lertzman, Ken; Simon Fraser University; lertzman@sfu.ca. |
Natal dispersal is a process that is critical in the spatial dynamics of populations, including population spread, recolonization, and gene flow. It is a central focus of conservation issues for many vertebrate species. Using data for 77 bird and 68 mammal species, we tested whether median and maximum natal dispersal distances were correlated with body mass, diet type, social system, taxonomic family, and migratory status. Body mass and diet type were found to predict both median and maximum natal dispersal distances in mammals: large species dispersed farther than small ones, and carnivorous species dispersed farther than herbivores and omnivores. Similar relationships occurred for carnivorous bird species, but not for herbivorous or omnivorous ones.... |
Tipo: Peer-Reviewed Reports |
Palavras-chave: Allometric scaling; Birds; Body mass; Comparative analysis; Connectedness; Diet type; Habitat alterations; Life history; Mammals; Movements; Natal dispersal distances; Probability density function. |
Ano: 2000 |
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Registros recuperados: 119 | |
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