RESUMOO objetivo desta pesquisa foi avaliar o efeito da idade no ajuste de funções de afilamento e na evolução do sortimento em árvores masculinas e femininas em plantios de Araucaria angustifolia. Foram amostradas 60 árvores da espécie em um plantio localizado no município de Laranjeiras do Sul, Paraná. Ajustou-se o polinômio de quinto grau para o total de dados, estratificando-os em classes de idade. Foi analisada a evolução do afilamento e do sortimento das árvores com a idade. Os resultados mostraram uma leve vantagem no uso de equações ajustadas por classes de idade e uma melhoria significativa na forma do tronco com o aumento da idade. As árvores femininas (0,9975 m 3 ) apresentaram crescimento mais elevado que as masculinas (0,9384 m 3 ) aos 30 anos. Volumes para os sortimentos mais nobres são produzidos somente a partir da classe de idade 11 a 15 anos.Palavras-chave: Floresta Ombrófila Mista, pinheiro do Paraná, equação de forma.
Effect of Age on Tapering and Assortment in Araucaria angustifolia Stands
ABSTRACTThe objective of this research was to evaluate the effect of age on adjust taper functions and evolution of the assortment of male and female trees of Araucaria angustifolia stands. Sixty trees were sampled in a plantation located in the municipality of Laranjeiras do Sul, Paraná state, Brazil. The fifth degree polynomials were adjusted to the whole data set, and they were stratified into age classes. The evolution of the tapering and assortment of trees was analyzed with age. The results showed a slight advantage in the use of equations adjusted for age classes and a significant improvement in the stem form with increasing age. The female trees presented higher growth (0.9975 m 3 ) than the male trees (0.9384 m 3 ) at 30 years of age. Volumes for the noblest assortments are produced only when the stand reaches the age class of 11 to 15 years.
Impacts of sheep ticks Ixodes ricinus on livestock, gamebirds and wildlife are of concern across Europe. The present study describes livestock and tick management by 36 farmers from three upland sites of conservation importance in North Wales, where farmers consider that ticks have increased during the last 25 years. Sheep, average densities of 2.0 animals per ha were treated with pour‐on acaricides in spring, again in July, and also when removed from the moor in autumn. Given acaricide efficacy rates, sheep were susceptible to tick bites for half the period on the moor. Sheep from 17 farms were examined for ticks. Infestations were similar between farms and in relation to the acaricide used, averaging 9.3 ticks per sheep, although they were lower where the interval between successive acaricide treatments was shorter. Repeated sampling of sheep and red grouse chicks showed no annual difference in tick burdens on grouse chicks, which averaged 6.2 ticks per chick, although there were three‐fold fewer ticks on sheep in 2018 than in previous years. Tick bite rates on sheep and grouse were higher than elsewhere in the U.K. Most farmers interviewed would aim to improve their tick management using longer‐lasting acaricides and treating sheep more frequently, although they would need advice and financial help, which is currently unavailable via Government funded agri‐environment schemes.
O carrapato Amblyomma aureolatum tem extrema importância em saúde pública, sendo considerado, depois do A. cajennense, o principal transmissor de Rickettsia rickettsii, agente causador da Febre Maculosa Brasileira. O presente estudo teve como objetivo relatar o caso de parasitismo por A. aureolatum em cachorro-do-mato (Cerdocyon thous) na região do Bioma Pampa, Rio Grande do Sul, Brasil. O animal foi encontrado morto em um trecho da BR-472, Km 585, na mesorregião sudoeste do Rio Grande do Sul, e submetido à necropsia. Foram encontrados e identificados, quatro espécimes de carrapatos, todos machos adultos de A. aureolatum. A presença de A. aureolatum, no exemplar de cachorro-do-mato de vida livre gera algumas questões pertinentes para futuros estudos, tais como a sazonalidade destes parasitos e a possibilidade de infestação e transmissão de doenças para animais domésticos e para o homem, considerando a proximidade principalmente nas propriedades rurais.
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