Habitat alteration can disrupt host–parasite interactions and lead to the emergence of new diseases in wild populations. The cerrado habitat of Brazil is being fragmented and degraded rapidly by agriculture and urbanization. We screened 676 wild birds from three habitats (intact cerrado, disturbed cerrado and transition area Amazonian rainforest-cerrado) for the presence of haemosporidian parasites (Plasmodium and Haemoproteus) to determine whether different habitats were associated with differences in the prevalence and diversity of infectious diseases in natural populations. Twenty one mitochondrial lineages, including 11 from Plasmodium and 10 from Haemoproteus were identified. Neither prevalence nor diversity of infections by Plasmodium spp. or Haemoproteus spp. differed significantly among the three habitats. However, 15 of the parasite lineages had not been previously described and might be restricted to these habitats or to the region. Six haemosporidian lineages previously known from other regions, particularly the Caribbean Basin, comprised 50–80% of the infections in each of the samples, indicating a regional relationship between parasite distribution and abundance.
Resumo-O objetivo deste trabalho foi calcular o quociente de Liocourt e avaliar a distribuição diamétrica em floresta natural com 84 hectares de Araucaria angustifolia, servindo de parâmetro para o seu manejo em propriedade rural com 176 hectares, localizada na Fazenda Pedras Brancas, Lages, SC, visando atingir o conceito de floresta balanceada. A distribuição diamétrica comportou-se como o esperado para florestas nativas, gerando uma curva de distribuição em J-invertido, demonstrando tratar-se de uma floresta não balanceada em fase de sucessão, por apresentar déficit de árvores nas maiores classes diamétricas. O valor do quociente de Liocourt foi de 1,33, semelhante a outros estudos com florestas naturais. Através da utilização do quociente de Liocourt, verifica-se a possibilidade de retirada de 54 árvores por hectare no conjunto das classes de frequência, para um diâmetro máximo desejado de 35 cm com redução de 7,4 m² ha-1 de área basal ou 620,8 m² para a floresta, evitando-se assim a estagnação, e 39 árvores por hectare para o diâmetro máximo de 40 cm com redução de 5,27 m² ha-1 de área basal ou 442,7 m 2 para floresta. Termos para indexação: Manejo florestal sustentado, floresta ombrófila mista, Araucaria angustifolia. Araucaria angustifolia management proposal to use the quotient of Liocourt and analysis of increase in a rural property in Lages,
Abstract:The Cantão region is a complex transition between Amazonia and Cerrado. Human interference is widespread even though the region is covered by two protected areas: the Cantão State Park and the Bananal Island/Cantão Environmental Protection Area. Bird inventories identified 418 species in the region, 382 on the present study. Of those, 27 are Amazonian and 9 Cerrado endemics. Four bird species are listed in the IUCN's red list as vulnerable: Penelope ochrogaster, Harpyhaliaetus coronatus, Cercomacra ferdinandi and Synallaxis simoni. This study also added eight species to the Cerrado biome list. The Cantão region is important for ten nearctic migrant species, including Pluvialis dominica, Actites macularia, Falco peregrinus and Progne subis. Habitat loss and deterioration caused by unsustainable tourism within the State Park, as well as cattle ranching and agriculture expansion within the Environmental Protected Area may have a strong impact on the populations of several bird species. We suggest that management actions should be focused on improving management and increasing coverage of protected areas to encompass marshlands and the Ipucas (natural forest patches) that are still well preserved in the region. Resumo: A região do Cantão é uma transição entre a Amazônia e o Cerrado. Mesmo com a presença de duas unidades de conservação, o Parque Estadual do Cantão e a Área de Proteção Ambiental Ilha do Bananal/Cantão, a interferência humana é intensa. Inventários avifaunísticos realizados nestas áreas identificaram 418 espécies, sendo 382 neste estudo. Destas, 27 são endêmicas amazônicas e 9 do Cerrado. Quatro espécies são consideradas vulneráveis de extinção: Penelope ochrogaster, Harpyhaliaetus coronatus, Cercomacra ferdinandi e Synallaxis simoni. Este estudo também adiciona ainda oito novas espécies para a lista total de espécies do bioma Cerrado. A região também se destaca pela presença de migratórias neárticas, sendo identificadas dez espécies, entre elas, Pluvialis dominica, Actites macularia, Falco peregrinus e Progne subis. Ainda que as unidades de conservação locais exerçam um importante papel na conservação destas espécies, diversas ameaças colocam em risco suas populações, principalmente o turismo desorganizado no Parque e a expansão da agropecuária na APA. Sugere-se a realização de ações de manejo e a ampliação das áreas de conservação priorizando as florestas, varjões e Ipucas (capões de mata natural) ainda bem preservados na região. Palavras-chave: conservação de aves, Tocantins, vale do rio Araguaia.
RESUMO ABSTRACT Introduction:In Tocantins, the behavior of malaria differs between microregions, with predominance of imported cases. This study describes a spatial analysis on malaria in the state covering 2003 to 2008, which sought to identify the incidence of autochthonous and imported cases, and the origin of the latter, in the microregions. Methods: This was a retrospective study using secondary data. The data source was the epidemiological surveillance information system for malaria (SIVEP-Malária), and the data were analyzed using the Epi Info version 3.5.1 and Bioestat version 5.0 statistical software. Results: It was found that malaria was not homogeneously distributed in all municipalities. The area of highest priority comprised municipalities located in microregions in the west of the state, at the border of Pará, which also had the highest number of autochthonous cases. The association between the autochthonous and imported cases and the Plasmodium species showed a statistically significant difference (G = 54.25; p < 0.0001). Among the eight microregions, Miracema do Tocantins, Araguaína and Bico do Papagaio accounted for 75.8% of the cases and, among these, eleven municipalities stood out. Regarding provenance, the State of Pará showed widespread distribution with 85.5% of the total, followed by French Guiana with 7.4%. Conclusions: These results demonstrated the predominance of imported cases and the difference between municipalities and microregions, and showed the influence of neighboring states in determining the areas of greatest risk. These data are important, since they contribute towards guiding and directing public policies regarding this disease in Tocantins.
BioOne Complete (complete.BioOne.org) is a full-text database of 200 subscribed and open-access titles in the biological, ecological, and environmental sciences published by nonprofit societies, associations, museums, institutions, and presses.
Regeneração e estrutura populacional de jatobá-da-mata (Hymenaea courbaril L.), em dois fragmentos com diferentes graus de perturbação antrópica RESUMO(Regeneração e estrutura populacional de jatobá-da-mata (Hymenaea courbaril L.), em dois fragmentos com diferentes graus de perturbação antrópica). O objetivo do estudo foi avaliar a estrutura populacional e os efeitos da intensidade luminosa no recrutamento de jatobá-da-mata (Hymenaea courbaril L.) em dois fragmentos de Mata de Galeria não-inundável, com diferentes graus de perturbação antrópica. Foi assumida a hipótese de que as populações diferem nas classes de tamanho (diâmetro e altura) e abundância dos indivíduos entre os fragmentos e o recrutamento responde às diferenças de luminosidade disponível no sub-bosque. Como espécie clímax dependente de luz amplamente distribuída e adaptada a ambientes heterogêneos, espera-se uma maior abundância e regeneração de jatobá-da-mata no fragmento com maior incidência luminosa. Em cada fragmento foram utilizadas 25 parcelas permanentes, alocadas de forma aleatória ao longo de transectos entre a borda da mata e o leito córrego posicionados perpendicularmente à margem do córrego. As plântulas foram amostradas no interior de cada parcela, a partir de quatro sub-parcelas de 2x2 m ao longo de uma linha central no comprimento da parcela. No sub-bosque, em cada sub-parcela, a radiação fotossinteticamente ativa foi determinada e os valores de transmitância (T%) foram obtidos a partir das medidas a pleno sol fora da mata. Nos dois fragmentos o maior número de indivíduos se concentrou nas menores classes de tamanho, mas não foi obtido um bom ajuste à distribuição exponencial negativa (J invertido ABSTRACT(Regeneration of Hymenaea courbaril L. in two forest fragments with diff erent degrees of human impact). Th e objective of this research was to study the population structure of Hymenaea courbaril in two fragments of non-fl ooded gallery forests with diff erent degrees of human impact. Th e research hypothesis was that populations present diff erent size classes and number of individuals between fragments and that recruitment is related to understory light. As a climax species that requires light, and a species that is adapted to a variety of environments, there would probably be a higher abundance and regeneration of H. courbaril in a fragment that has more light. Twenty-fi ve plots (10 x 20 m) were set in two fragments using transects between the forest edge and the stream bank. Th e seedlings were recorded within each plot by means of four subplots (2 x 2 m) in a central line along the plots. Within the understory the photosynthetic active radiation was determined and the transmittance values (T%) were calculated by measuring the sunlight in an open fi eld. In both fragments, more individuals were concentrated in the smaller size classes. However the population sizes in both fragments were not adjusted to the negative exponential distribution (reversed J curve). A linear regression analysis indicated that both the diameter and ...
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
334 Leonard St
Brooklyn, NY 11211
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.