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1.
Braz. j. biol ; 83: 1-7, 2023. map, ilus, tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1468895

RESUMO

Asiatic black bear is present in variety of habitats like broad-leaves and coniferous forests, extending form sea level to 4300m elevation and change their habitat for food purpose seasonally. The present study was conducted at Kaghan and Siran Valleys, District Mansehra, Khyber Pakhtunkhwa, Pakistan to assess habitat of black bear. Line transect method was used for observation of bear signs. Twelve meter circular radius plots were selected for the concern vegetation’s i.e. (trees, shrubs and herbs) and three to six plots were placed in each transect. At the result of sign survey, thirteen different categories of bear signs were recorded and encounter rate was calculated for each sign. A total of 1858 signs were observed during field surveys. Total (81%) coniferous species were recoded among trees, with the highest appearance of Pinus wallichiana (34.22%) and Spruce spp (27.76%), similarly broad leaves trees (18.56%) were also recoded from habitat plots. Most of the signs were encountered in bushy areas, whereas high number of Viburnum Spp (60.29%) was present. It is indicated that black bear prefers blend of Coniferous Trees, Viburnum and Ferns Species; probably because these plants provide enough food, protection, and meticulous shelter because more than 80% of habitat composed of these three species. Currently habitat destruction and increase in human population are the up-growing issues for wild animals (especially Asiatic black bear), which is highly sensitive to such problems. High levels of conservation efforts are recommended for the protection of black bear habitat and to avoid human interference in their territory.


O urso-negro asiático está presente em uma variedade de habitats, como folhas largas e florestas de coníferas, estendendo-se do nível do mar até 4.300 m de altitude e mudando seu habitat para fins alimentares sazonalmente. O presente estudo foi conduzido nos vales Kaghan e Siran, distrito de Mansehra, Khyber Pakhtunkhwa, Paquistão, para avaliar o habitat do urso preto. O método de transecto linear foi usado para a observação de sinais do urso. Parcelas de raio circular de 12 m foram selecionadas para a vegetação de preocupação, ou seja, árvores, arbustos e ervas, e 3 a 6 parcelas foram colocadas em cada transecto. No resultado da pesquisa de sinais, 13 categorias diferentes de sinais de urso foram registradas e a taxa de encontro foi calculada para cada sinal. Um total de 1858 sinais foi observado durante os levantamentos de campo. O total (81%) de espécies de coníferas foi recodificado entre as árvores, com maior aparecimento de Pinus wallichiana (34,22%) e Spruce spp (27,76%); árvores de folhas largas (18,56%) também foram recodificadas em parcelas de habitat. A maioria dos sinais foi encontrada em áreas com arbustos, enquanto um alto número de Viburnum spp (60,29%) estava presente. É indicado que o urso-negro prefere a mistura de árvores coníferas, espécies de viburnos e samambaias; provavelmente porque essas plantas fornecem alimento suficiente, proteção e abrigo meticuloso porque mais de 80% do habitat é composto por essas três espécies. Atualmente, a destruição do habitat e o aumento da população humana são questões crescentes para os animais selvagens, especialmente o urso-negro asiático, que é altamente sensível a esses problemas. Altos níveis de esforços de conservação são recomendados para a proteção do habitat do urso-negro e para evitar a interferência humana em seu território.


Assuntos
Animais , Ecossistema , Picea , Pinus/classificação , Ursidae , Viburnum
2.
Braz. J. Biol. ; 83: 1-7, 2023. mapas, ilus, tab, graf
Artigo em Inglês | VETINDEX | ID: vti-765472

RESUMO

Asiatic black bear is present in variety of habitats like broad-leaves and coniferous forests, extending form sea level to 4300m elevation and change their habitat for food purpose seasonally. The present study was conducted at Kaghan and Siran Valleys, District Mansehra, Khyber Pakhtunkhwa, Pakistan to assess habitat of black bear. Line transect method was used for observation of bear signs. Twelve meter circular radius plots were selected for the concern vegetations i.e. (trees, shrubs and herbs) and three to six plots were placed in each transect. At the result of sign survey, thirteen different categories of bear signs were recorded and encounter rate was calculated for each sign. A total of 1858 signs were observed during field surveys. Total (81%) coniferous species were recoded among trees, with the highest appearance of Pinus wallichiana (34.22%) and Spruce spp (27.76%), similarly broad leaves trees (18.56%) were also recoded from habitat plots. Most of the signs were encountered in bushy areas, whereas high number of Viburnum Spp (60.29%) was present. It is indicated that black bear prefers blend of Coniferous Trees, Viburnum and Ferns Species; probably because these plants provide enough food, protection, and meticulous shelter because more than 80% of habitat composed of these three species. Currently habitat destruction and increase in human population are the up-growing issues for wild animals (especially Asiatic black bear), which is highly sensitive to such problems. High levels of conservation efforts are recommended for the protection of black bear habitat and to avoid human interference in their territory.(AU)


O urso-negro asiático está presente em uma variedade de habitats, como folhas largas e florestas de coníferas, estendendo-se do nível do mar até 4.300 m de altitude e mudando seu habitat para fins alimentares sazonalmente. O presente estudo foi conduzido nos vales Kaghan e Siran, distrito de Mansehra, Khyber Pakhtunkhwa, Paquistão, para avaliar o habitat do urso preto. O método de transecto linear foi usado para a observação de sinais do urso. Parcelas de raio circular de 12 m foram selecionadas para a vegetação de preocupação, ou seja, árvores, arbustos e ervas, e 3 a 6 parcelas foram colocadas em cada transecto. No resultado da pesquisa de sinais, 13 categorias diferentes de sinais de urso foram registradas e a taxa de encontro foi calculada para cada sinal. Um total de 1858 sinais foi observado durante os levantamentos de campo. O total (81%) de espécies de coníferas foi recodificado entre as árvores, com maior aparecimento de Pinus wallichiana (34,22%) e Spruce spp (27,76%); árvores de folhas largas (18,56%) também foram recodificadas em parcelas de habitat. A maioria dos sinais foi encontrada em áreas com arbustos, enquanto um alto número de Viburnum spp (60,29%) estava presente. É indicado que o urso-negro prefere a mistura de árvores coníferas, espécies de viburnos e samambaias; provavelmente porque essas plantas fornecem alimento suficiente, proteção e abrigo meticuloso porque mais de 80% do habitat é composto por essas três espécies. Atualmente, a destruição do habitat e o aumento da população humana são questões crescentes para os animais selvagens, especialmente o urso-negro asiático, que é altamente sensível a esses problemas. Altos níveis de esforços de conservação são recomendados para a proteção do habitat do urso-negro e para evitar a interferência humana em seu território.(AU)


Assuntos
Animais , Ursidae , Ecossistema , Pinus/classificação , Viburnum , Picea
3.
Sci Rep ; 10(1): 12113, 2020 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-32694547

RESUMO

Herbivores modulate the structure and composition of plant communities, including plant invasions. This is conditioned by plant palatability which can be reduced by its chemical or physical traits. The effects that ungulates browsing has on pine invasions are variable and the empirical evidence on the causes of this variability is scarce. We experimentally explored how sheep browsing preference varies between seedlings of pine species with different invasiveness; Pinus contorta (high invasiveness), P. ponderosa (medium invasiveness), P. radiata (medium invasiveness) and P. jeffreyi (low invasiveness). Secondly, we quantified anti-herbivory chemical compounds and physical traits of these species and related them with sheep preference observed. The browsing incidence of P. contorta was 68%, P. ponderosa 58%, P. radiata 29%, and P. jeffreyi 84%. Among anti-herbivory traits analyzed, α-pinene concentration had a negative effect on the probability of a terminal bud being browsed and on browsing intensity. Meanwhile, foliar toughness was negatively related to browsing intensity and water concentration was positively related to browsing intensity. Also, the most invasive species, P. contorta, was highly damaged. Thus, sheep herbivory could be slowing pine invasion rate; suggesting that could be considered a tool to control early invasions, especially for this particular species.


Assuntos
Pinus/crescimento & desenvolvimento , Resinas Vegetais/química , Ovinos/fisiologia , Terpenos/química , Ração Animal , Animais , Argentina , Herbivoria , Espécies Introduzidas , Pinus/química , Pinus/classificação , Densidade Demográfica
4.
Rev. Ciênc. Agrovet. (Online) ; 19(4): 474-482, dez. 2020. tab, graf
Artigo em Português | VETINDEX | ID: biblio-1488423

RESUMO

The use of tools such as forest modeling becomes increasingly important in forest planning as they generate accurate estimates of the stands production. The aim of this study was to adjust the hypsometric, volumetric, and taper models for four Pinus species in the Mountain region of Santa Catarina in Brazil. The species Pinus taeda, Pinus elliottii, Pinus greggii, and Pinus patula were all planted and maintained under the same forest management plan. The 14-year-old stand is located in the municipality of Correia Pinto, Santa Catarina, Brazil. For the analyses, mathematical models were adjusted based on data from the forest census. The following statistical criteria were used to choose the most appropriate model: the adjusted coefficient of determination (R² adj), standard error (Sy.x%) and graphic residual analysis. The hypsometric equations presented relatively low values for the adjusted R², ranging from 0.14 to 0.35 for the species, while the values for Sy.x% ranged between 7.67% and 4.86%. As for the volumetric equations, the adjusted R² was above 0.91, and Sy.x% was under 10%. With regard to the taper functions, the Hradetzky model most appropriately described the stem profile of the species, with values above 0.96 for the adjusted R² and under 10% for Sy.x%. The Naslund, Spurr I and II, and modified Naslund models were selected to estimate the species volumetry.


O emprego de ferramentas como a modelagem florestal torna-se cada vez mais importantes no planejamento florestal pois geram estimativas acuradas da produção dos povoamentos. O objetivo do estudo foi realizar o ajuste de modelos hipsométricos, volumétricos e de afilamento para quatro espécies de Pinus na Região Serrana de Santa Catarina. As espécies utilizadas foram Pinus taeda, Pinus elliottii, Pinus greggii e Pinus patula todas implantadas e conduzidas sobre o mesmo plano de manejo florestal. O povoamento está localizado no município de Correia Pinto, Santa Catarina, com 14 anos de idade. Para as análises foram ajustados modelos matemáticos com base nos dados do censo florestal. Para a escolha do melhor modelo utilizaram-se os critérios estatísticos: o coeficiente de determinação ajustado (R²aj), erro padrão da estimativa (Syx%), análise gráfica dos resíduos. As equações hipsométricas apresentaram R² ajustado relativamente baixos, com valores variando entre 0,14 e 0,35 para as espécies e Syx% variando entre 7,67% a 4,86%. Em relação as equações volumétricas, o R² ajustado ficou acima de 0,91 e o Syx% foi inferior a 10%. No que diz respeito as funções de afilamento o melhor modelo para descrever o perfil do fuste das espécies foi Hradetzky, com R² ajustado acima de 0,96 e Syx% inferior a 10%. Os modelos de Naslund, Spurr I e II e Naslund modificado foram selecionados


Assuntos
Pinus/anatomia & histologia , Pinus/classificação , Pinus/crescimento & desenvolvimento , Titulometria
5.
R. Ci. agrovet. ; 19(4): 474-482, dez. 2020. tab, graf
Artigo em Português | VETINDEX | ID: vti-28753

RESUMO

The use of tools such as forest modeling becomes increasingly important in forest planning as they generate accurate estimates of the stands production. The aim of this study was to adjust the hypsometric, volumetric, and taper models for four Pinus species in the Mountain region of Santa Catarina in Brazil. The species Pinus taeda, Pinus elliottii, Pinus greggii, and Pinus patula were all planted and maintained under the same forest management plan. The 14-year-old stand is located in the municipality of Correia Pinto, Santa Catarina, Brazil. For the analyses, mathematical models were adjusted based on data from the forest census. The following statistical criteria were used to choose the most appropriate model: the adjusted coefficient of determination (R² adj), standard error (Sy.x%) and graphic residual analysis. The hypsometric equations presented relatively low values for the adjusted R², ranging from 0.14 to 0.35 for the species, while the values for Sy.x% ranged between 7.67% and 4.86%. As for the volumetric equations, the adjusted R² was above 0.91, and Sy.x% was under 10%. With regard to the taper functions, the Hradetzky model most appropriately described the stem profile of the species, with values above 0.96 for the adjusted R² and under 10% for Sy.x%. The Naslund, Spurr I and II, and modified Naslund models were selected to estimate the species volumetry.(AU)


O emprego de ferramentas como a modelagem florestal torna-se cada vez mais importantes no planejamento florestal pois geram estimativas acuradas da produção dos povoamentos. O objetivo do estudo foi realizar o ajuste de modelos hipsométricos, volumétricos e de afilamento para quatro espécies de Pinus na Região Serrana de Santa Catarina. As espécies utilizadas foram Pinus taeda, Pinus elliottii, Pinus greggii e Pinus patula todas implantadas e conduzidas sobre o mesmo plano de manejo florestal. O povoamento está localizado no município de Correia Pinto, Santa Catarina, com 14 anos de idade. Para as análises foram ajustados modelos matemáticos com base nos dados do censo florestal. Para a escolha do melhor modelo utilizaram-se os critérios estatísticos: o coeficiente de determinação ajustado (R²aj), erro padrão da estimativa (Syx%), análise gráfica dos resíduos. As equações hipsométricas apresentaram R² ajustado relativamente baixos, com valores variando entre 0,14 e 0,35 para as espécies e Syx% variando entre 7,67% a 4,86%. Em relação as equações volumétricas, o R² ajustado ficou acima de 0,91 e o Syx% foi inferior a 10%. No que diz respeito as funções de afilamento o melhor modelo para descrever o perfil do fuste das espécies foi Hradetzky, com R² ajustado acima de 0,96 e Syx% inferior a 10%. Os modelos de Naslund, Spurr I e II e Naslund modificado foram selecionados(AU)


Assuntos
Pinus/anatomia & histologia , Pinus/classificação , Pinus/crescimento & desenvolvimento , Titulometria
6.
Am J Bot ; 105(4): 711-725, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29683492

RESUMO

PREMISE OF THE STUDY: Both incomplete lineage sorting and reticulation have been proposed as causes of phylogenetic incongruence. Disentangling these factors may be most difficult in long-lived, wind-pollinated plants with large population sizes and weak reproductive barriers. METHODS: We used solution hybridization for targeted enrichment and massive parallel sequencing to characterize low-copy-number nuclear genes and high-copy-number plastomes (Hyb-Seq) in 74 individuals of Pinus subsection Australes, a group of ~30 New World pine species of exceptional ecological and economic importance. We inferred relationships using methods that account for both incomplete lineage sorting and reticulation. KEY RESULTS: Concatenation- and coalescent-based trees inferred from nuclear genes mainly agreed with one another, but they contradicted the plastid DNA tree in recovering the Attenuatae (the California closed-cone pines) and Oocarpae (the egg-cone pines of Mexico and Central America) as monophyletic and the Australes sensu stricto (the southern yellow pines) as paraphyletic to the Oocarpae. The plastid tree featured some relationships that were discordant with morphological and geographic evidence and species limits. Incorporating gene flow into the coalescent analyses better fit the data, but evidence supporting the hypothesis that hybridization explains the non-monophyly of the Attenuatae in the plastid tree was equivocal. CONCLUSIONS: Our analyses document cytonuclear discordance in Pinus subsection Australes. We attribute this discordance to ancient and recent introgression and present a phylogenetic hypothesis in which mostly hierarchical relationships are overlain by gene flow.


Assuntos
Pinus/genética , Fluxo Gênico , Genes de Plantas/genética , Marcadores Genéticos/genética , Hibridização Genética , Modelos Genéticos , Filogenia , Pinus/classificação , Alinhamento de Sequência
7.
BMC Evol Biol ; 17(1): 213, 2017 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-28893173

RESUMO

BACKGROUND: Homoplasy affects demographic inference estimates. This effect has been recognized and corrective methods have been developed. However, no studies so far have defined what homoplasy metrics best describe the effects on demographic inference, or have attempted to estimate such metrics in real data. Here we study how homoplasy in chloroplast microsatellites (cpSSR) affects inference of population expansion time. cpSSRs are popular markers for inferring historical demography in plants due to their high mutation rate and limited recombination. RESULTS: In cpSSRs, homoplasy is usually quantified as the probability that two markers or haplotypes that are identical by state are not identical by descent (Homoplasy index, P). Here we propose a new measure of multi-locus homoplasy in linked SSR called Distance Homoplasy (DH), which measures the proportion of pairwise differences not observed due to homoplasy, and we compare it to P and its per cpSSR locus average, which we call Mean Size Homoplasy (MSH). We use simulations and analytical derivations to show that, out of the three homoplasy metrics analyzed, MSH and DH are more correlated to changes in the population expansion time and to the underestimation of that demographic parameter using cpSSR. We perform simulations to show that Approximate Bayesian Computation (ABC) can be used to obtain reasonable estimates of MSH and DH. Finally, we use ABC to estimate the expansion time, MSH and DH from a chloroplast SSR dataset in Pinus caribaea. To our knowledge, this is the first time that homoplasy has been estimated in population genetic data. CONCLUSIONS: We show that MSH and DH should be used to quantify how homoplasy affects estimates of population expansion time. We also demonstrate how ABC provides a methodology to estimate homoplasy in population genetic data.


Assuntos
Cloroplastos/genética , Repetições de Microssatélites , Pinus/genética , Teorema de Bayes , América Central , Simulação por Computador , Genética Populacional , Haplótipos , Modelos Genéticos , Pinus/classificação
8.
Forensic Sci Int Genet ; 21: e6-9, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26626827

RESUMO

Fast, accurate detection of plant species and their hybrids using molecular tools will facilitate assessment and monitoring of timber tracing evidence. In this study the origin of unknown pine samples is determined for a case of timber theft in the region of Araucania southern Chile. We evaluate the utility of the trnL marker region for species identification applied to pine wood based on High Resolution Melting. This efficient tracing methods can be incorporated into forestry applications such as certification of origin. The object of this work was genotype identification using high-resolution melting (HRM) and trnL approaches for Pinus radiata (Don) in timber tracing evidence. Our results indicate that trnL is a very sensitive marker for delimiting species and HRM analysis was used successfully for genotyping Pinus samples for timber tracing purposes. Genotyping samples by HRM analysis with the trnL1 approach allowed us to differentiate two wood samples from the Pinaceae family: Pinus radiata (Don) and Pseudotsuga menziesii (Mirb.) Franco. The same approach with Pinus trnL wood was not able to discriminate between samples of Pinus radiata, indicating that the samples were genetically indistinguishable, possibly because they have the same genotype at this locus. Timber tracing with HRM analysis is expected to contribute to future forest certification schemes, control of illegal trading, and molecular traceability of Pinus spp.


Assuntos
DNA de Plantas/análise , Genética Forense/métodos , Desnaturação de Ácido Nucleico/genética , Pinus/genética , Chile , DNA de Plantas/genética , Genes de Plantas/genética , Genótipo , Pinus/classificação , Especificidade da Espécie , Madeira/classificação , Madeira/genética
9.
Genet Mol Res ; 14(2): 4549-56, 2015 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-25966228

RESUMO

The taxonomic status of Pinus henryi, a rare species endemic to China, is still ambiguous. In this study, the genetic relationships among P. henryi and its congeners (P. tabulaeformis, P. tabulaeformis var. mukdensis, and P. massoniana) were revealed using multiplexed microsatellite markers, including chloroplast microsatellites, nuclear microsatellites, and expressed sequence tag microsatellites. The results refute the hypothesis that P. henryi is a subspecies of P. tabulaeformis or P. massoniana and support the suggestion that it may be a distinct species closely related to P. tabulaeformis.


Assuntos
Repetições de Microssatélites , Filogenia , Pinus/genética , Etiquetas de Sequências Expressas , Genoma de Cloroplastos , Pinus/classificação
10.
Genet Mol Res ; 12(3): 3742-9, 2013 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-24085435

RESUMO

The effect of tree diversity on productivity in subtropical forests in China is poorly understood. We investigated the biomasses of trees, understory vegetation, coarse roots, and fine roots with varying proportions of Pinus massoniana, mixed with other tree species in stands of the same age, to examine the effects of tree diversity. With an increase of P. massoniana proportion, the tree and understory biomasses increased at first, and then gradually decreased. As expected, the biomass of fine roots decreased with soil depth. Stands with 40 to 60% P. massoniana had the highest biomass, whereas stands with <20% P. massoniana had the least biomass. Stands with <20% P. massoniana had the least understory biomass, whereas those with 20 to 40% Masson pine had the least fine root biomass.


Assuntos
Biodiversidade , Biomassa , Pinus/crescimento & desenvolvimento , Árvores/classificação , China , Pinus/classificação , Raízes de Plantas/química , Solo
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