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61.
Maria João Verdasca Ana Sofia Leitão Joana Santana Miguel Porto Susana Dias Pedro Beja 《Biological conservation》2012,146(1):14-23
In cultural landscapes there are often negative biodiversity consequences of agricultural abandonment and subsequent scrub and forest encroachment, due to homogenization and the loss of early-successional habitats. The common forestry practice of removing understory vegetation to prevent fire hazard (fuel management) probably has the side-effect of ameliorating these consequences, but it is uncertain whether it effectively restores habitats for early-successional species. Here we examine the influence of time since fuel management and management frequency on butterfly assemblages, using a chronosequence of cork oak (Quercus suber) stands spanning about 70 years. Overall species richness increased immediately after management and abundances peaked about 2–3 years later, while both declined thereafter for about 10–20 years to pre-disturbance levels. Richness and abundances were also much higher in recurrently managed stands. Most life history groups showed successional trends similar to the overall species richness and abundances, though consistent positive effects of fuel management were only observed for species with univoltine life cycle, herbaceous layer feeding, larval overwintering, and intermediate body size. Individual species were largely associated with recent and recurrent management, though a few specialists occurred most often in undisturbed stands. These findings suggest that fuel management at <10 years intervals is strongly positive for butterfly assemblages in landscapes under land abandonment. However, to maintain the overall forest biodiversity it is critical that patches of undisturbed habitat are also retained at the landscape scale. 相似文献
62.
Pmila Carolini Gonalves da Silva Camila Celeste Brando Ferreira Ítavo Luís Carlos Vinhas Ítavo Marina de Nadai Bonin Gomes Gelson Luís Dias Feij Kedma Leonora Silva Monteiro Ferelli Natlia da Silva Heimbach Jonilson Araújo da Silva Gleice Kelli Ayardes de Melo Marília Williani Filgueira Pereira 《Animal Science Journal》2020,91(1)
Our hypothesis suggests an improvement in carcass and meat quality of pasture‐finished animals by introducing concentrate feed into diets. This study aimed to evaluate the effect of different levels of protein‐energy supplementation on carcass and meat characteristics of Texel lambs raised on Brachiaria pastures, and compare the results with those obtained from confined animals. Thirty 2‐month‐old intact lambs were divided into five treatments: pasture with mineral supplementation, pasture containing daily supplies of 0.8, 1.6, and 2.4% BW protein‐energy supplementation, and confinement (reference treatment). All animals were slaughtered 104 days after the beginning of the experiment. Lambs submitted to 1.6% and 2.4% BW supplementation presented similar characteristics to animals kept in confinement and were superior to animals treated with 0 or 0.8% of BW supplementation levels (p < .05). Increases of subcutaneous fat thickness were verified for 0.0, 0.8, 1.6, 2.4% BW, and confinement treatments, being respectively of 0.25, 0.74, 1.61, 1.69, and 1.98. Conversely, treatments had no influence on meat physical‐chemical characteristics, being all considered moderately soft, juicy (tender), and with mild tastes and odors. Lambs raised on Brachiaria pastures have high‐quality meat, but more protein‐energy supplementation is needed to be an alternative for the feedlots for young animals. 相似文献
63.
Maximilian Estevan Oliveira Jssica Campanholi Roberta Lima Cavalcante Felipe Silveira Moreno Edson Hideaki Yoshida Murilo Melo Juste Dini lvio Franco de Camargo Aranha Jos Carlos Cogo Lourdes Dias Stephen Hyslop Denise Grotto Valquíria Miwa Hanai‐Yoshida Yoko Oshima‐Franco 《Journal of Veterinary Emergency and Critical Care》2020,30(3):286-294
64.
65.
Fábio Luiz Partelli Marcos Góes Oliveira André Monzoli Covre Henrique Duarte Vieira Jairo Rafael Machado Dias Heder Braun 《Journal of plant nutrition》2013,36(19):2536-2546
The objective of this study was to establish a nutrient sufficiency range and DRIS standards of Conilon coffee grown in southern Bahia, Brazil for the pre-flowering and grain-filling stages and to perform a nutritional diagnosis of these plants using different methods. The collections were performed in 24 Conilon coffee farm fields to establish the leaf nutritional standards, and 278 samples were collected to the nutritional diagnosis. The nutritional diagnosis was performed by using the sufficiency range criterion and the DRIS method. The nutrient sufficiency range and the DRIS standards must be specific to each phenological stage of the Conilon coffee plants. The leaf concentrations of calcium (Ca), sulfur (S), and boron (B) were higher in the pre-flowering stage; and the leaf concentrations of nitrogen (N), potassium (K), copper (Cu), and zinc (Zn) were higher in the grain-filling stage. 相似文献
66.
Ana Lúcia Tourinho Larissa de Souza Lança Fabricio Beggiato Baccaro Sidclay Calaça Dias 《Pedobiologia》2014
Tropical arthropod surveys generally use a combination of complementary sampling methods to increase the detection of species and individuals, and to decrease the number of singletons. However, given the high arthropod abundance and the taxonomic challenges of arthropod surveys, the combination of different sampling methods may be inefficient and may increase survey costs. Harvestmen were sampled using beating tray, nocturnal search, leaf-litter manual sorting and Winkler apparatus in 70 plots distributed in two areas in Central Amazonia. Every sampled method documented different assemblages, and only the nocturnal search method proved to be efficient in representing both harvestmen richness and composition. Given the data collected from leaf-litter manual sorting, Winkler apparatus and beating tray can be used in inventories to increase the number of species collected, but may be less useful for applied or monitoring studies. Although pooling data from three methods was effective to obtain an overview of species richness, it may not be the more efficient strategy for studies of assemblage associations with environmental variables. As each method may sample distinct assemblages that have different responses to the surrounding environment, pooling data from these different methods may obfuscate patterns of assemblage composition related to environmental factors instead of clarifying them. 相似文献
67.
Changing porosity of knitted structures by changing tightness 总被引:1,自引:0,他引:1
A geometrical model of plain knitted structures is discussed in depth to understand the yarn path in a knitted loop. A theoretical
model has been created to predict the porosity of a knitted structure depending on the geometrical parameters, such as course
spacing, wale spacing, stitch length, fabric thickness, count of yarn and fibre density. Polyester and nylon plain knitted
fabrics were produced to different tightness, and porosity was determined by measuring the weight. The validity of the model
was confirmed by experimental results, using different plain knit fabrics. The porosity of a knitted structure can be changed
by reducing the yarn thickness and the stitch length; however this would influence the courses and wales per unit length in
the structure. 相似文献
68.
Menezes IA Marques MS Santos TC Dias KS Silva AB Mello IC Lisboa AC Alves PB Cavalcanti SC Marçal RM Antoniolli AR 《Fitoterapia》2007,78(3):192-195
The essential oil of the Hyptis fruticosa leaves was analyzed by GC/MS and evaluated for antinociceptive property as well as acute toxicity in mice. The essential oil, at doses of 100, 200, and 400 mg/kg (s.c.), produced significant inhibition of acetic acid-induced writhing, but did not manifest a significant effect in hot-plate test. There was no acute toxicity at doses up to 5 g/kg. Bicyclogermacrene, 1,8-cineole, alpha-pinene, and beta-caryophyllene were the major compounds detected in the essential oil. 相似文献
69.
The polymer conformation structure of gluten extracted from a Polish wheat cultivar, Korweta, and gluten subfractions obtained from 2 U.K. breadmaking and biscuit flour cultivars, Hereward and Riband, was investigated using attenuated total reflectance Fourier transform infrared spectroscopy (ATR‐FTIR). The results showed the conformation of proteins varied between flour, hydrated flour, and hydrated gluten. The β‐sheet structure increased progressively from flour to hydrated flour and to hydrated gluten. In hydrated gluten protein fractions comprising gliadin, soluble glutenin, and gel protein, β‐sheet structure increased progressively from soluble gliadin and glutenin to gluten and gel protein; β‐sheet content was also greater in the gel protein from the breadmaking flour Hereward than the biscuit flour Riband. 相似文献
70.
Ananias Francisco Dias Júnior Ana Lúcia Martins Sodero Pincelli Ana Paula Camara da Silva álison Moreira da Silva Natália Dias de Souza Mario Tommasiello Filho José Otávio Brito 《林业研究》2021,42(6):2313-2321
As forests in neotropical regions,particularly in developing countries,are devastated,interventions to restore biodiversity and its ecological functions are nee... 相似文献