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71.
Bergmann GT Bates ST Eilers KG Lauber CL Caporaso JG Walters WA Knight R Fierer N 《Soil biology & biochemistry》2011,43(7):1450-1455
Verrucomicrobia are ubiquitous in soil, but members of this bacterial phylum are thought to be present at low frequency in soil, with few studies focusing specifically on verrucomicrobial abundance, diversity, and distribution. Here we used barcoded pyrosequencing to analyze verrucomicrobial communities in surface soils collected across a range of biomes in Antarctica, Europe, and the Americas (112 samples), as well as soils collected from pits dug in a montane coniferous forest (69 samples). Data collected from surface horizons indicate that Verrucomicrobia average 23% of bacterial sequences, making them far more abundant than had been estimated. We show that this underestimation is likely due to primer bias, as many of the commonly used PCR primers appear to exclude verrucomicrobial 16S rRNA genes during amplification. Verrucomicrobia were detected in 180 out of 181 soils examined, with members of the class Spartobacteria dominating verrucomicrobial communities in nearly all biomes and soil depths. The relative abundance of Verrucomicrobia was highest in grasslands and in subsurface soil horizons, where they were often the dominant bacterial phylum. Although their ecology remains poorly understood, Verrucomicrobia appear to be dominant in many soil bacterial communities across the globe, making additional research on their ecology clearly necessary. 相似文献
72.
73.
Propelled by urbanization, rising incomes, and changing diets, food markets have been expanding in Africa and South Asia, creating the vast potential for job and income opportunities along food supply chains and, hence, for poverty reduction. The novel coronavirus(COVID-19) that spread to a pandemic in early 2020 provokes enormous setbacks to this expansion. This, however, should provide lessons regarding the importance of resilient and inclusive food systems. Emergency responses to COVID-19 should consider interventions towards that end and leverage the opportunities provided by food markets growth as economies recover from the present economic recession. This paper assesses options of how this could be done by facilitating the better functioning and interconnectedness of the many small and medium-sized enterprises that are proliferating along the "hidden middle" of food value chains in storage, logistics, transportation, and wholesale and retail distribution. It also explores how policies can help smallholder farmers connect to this "hidden middle" in more gainful ways and help them climb out of poverty as well. 相似文献
74.
Eberhardt Diogo Marchão Robélio Quiquampoix Hervé Le Guernevé Christine Ramaroson Volaniaina Sauvadet Marie Muraoka Takashi Becquer Thierry 《Journal of Soils and Sediments》2021,21(2):1024-1037
Journal of Soils and Sediments - Phosphorus (P) is often the main limiting factor for plant growth in highly weathered tropical soils. Phosphate use efficiency and crop yields could be increased in... 相似文献
75.
Redesigning IT systems for specific user groups encompasses a lot of effort with respect to analysing and understanding user behaviour. The goal of this paper is to provide insights into patterns of behaviour of agricultural users, during the usage of a decision support system called OPTIRas™. This system aids agricultural users in their cultivar selection activities. We analyse logs resulting from OPTIRas™, and we get insights into user’s navigational patterns. We claim that the results of our analysis can be used to support the redesign of decision support systems in order to address specific agricultural users’ characteristics. 相似文献
76.
Ingestive behaviour of steers grazing Brachiaria brizantha cultivar Marandu and in feedlot in Brazil
de Souza Sinvaldo Oliveira Silva Robério Rodrigues da Silva Fabiano Ferreira de Carvalho Gleidson Giordano Pinto da Silva Ana Paula Gomes da Silva João Wilian Dias Santos Laize Vieira 《Tropical animal health and production》2019,51(8):2161-2166
Tropical Animal Health and Production - The objective of this study was to evaluate the ingestive behaviour of steers grazing Brachiaria brizantha cv. Marandu and in feedlot regimen in Brazil.... 相似文献
77.
Costa Evely Giovanna Leite da Silva Fabiano Ferreira Silva Robério Rodrigues Porto Antonio Ferraz Santiago Bismarck Moreira Rocha Leone Campos Cruz Aline Gonçalves Guedes Anna Caroline Ferreira Neto Teotônio Martins Vieira Edvaldo Alves 《Tropical animal health and production》2019,51(8):2505-2511
Tropical Animal Health and Production - The objective of this study was to evaluate the inclusion of increasing levels of licuri meal as a substitute for soybean bran in the diet of pasture-based... 相似文献
78.
79.
Isolated trees may significantly enhance biodiversity at the landscape level. However, our understanding of their impacts
is still poor, particularly in environments with high soil moisture where research on this topic has been comparatively limited.
We examined understorey vegetation and soil oribatid mite assemblages under live and dead Scots pine trees and in open treeless
areas, all within the same Scottish upland wet heath system, to determine whether isolated live trees affected the understorey
and mite components of the ecosystem, and whether these effects occurred in parallel. We also explored whether these responses
might result from tree-driven reductions in soil moisture content. Live trees reduced soil moisture (relative to wet heath
and beneath dead trees) and appeared to change vegetation from wet heath to dry heath type communities. These effects were
strongly related to tree trunk diameter (tree size). No major effects of dead trees on understorey vegetation or soil moisture
were apparent. Higher mite species abundance and richness were found under live trees than in treeless open heath. Although
mite abundances were lower under dead trees than live trees, richness remained similar, thus different factors seem to be
regulating mite abundance and community composition. These findings indicate that landscape-level biodiversity responses to
environmental change such as habitat fragmentation cannot be predicted from vegetation patterns alone, and that even in heavily
fragmented landscapes comparatively small patches such as isolated individual trees can enhance biodiversity. 相似文献
80.
Daniele Soares Barroso Neves Robério Rodrigues Silva Fabiano Ferreira da Silva Laize Vieira Santos George Abreu Filho Sinvaldo Oliveira de Souza Marceliana da C. Santos Weder Jansen Rocha Ana Paula Gomes da Silva Mateus de Melo Lisboa Maria Magna Silva Pereira Venício Macedo Carvalho 《Tropical animal health and production》2018,50(7):1411-1416
The aim of this study was to evaluate the effect of increasing concentrate supplementation levels on the intake, nutrient digestibility, and performance of crossbred steers during the dry period of the year. The experiment was developed on Princesa do Mateiro farm, in the municipality of Ribeirão do Largo, located in the southwest region of Bahia State, Brazil. Forty uncastrated male crossbred (½ Holstein-Zebu) steers with an average body weight (BW) of 232.55?±?24.97 kg were distributed into four treatments in a completely randomized design with ten replicates. The animals were managed in an experimental area formed by Brachiaria brizantha cv. Marandu, in an intermittent grazing system. Treatments consisted of the following supplementation levels: 0.2% BW, with 60% crude protein (CP); 0.3% BW, with 40% CP; 0.4% BW, with 30% CP; and 0.5% BW, with 24% CP. The intakes of forage dry matter in kg/day and %BW and neutral detergent fiber corrected for ash and protein (NDFap) in %BW decreased linearly, whereas the intake of non-fibrous carbohydrates corrected for ash and protein in kg/day and average daily gain increased linearly. Therefore, the use of supplementation at 0.5% BW (24% crude protein) to provide gains of up to 0.500 kg/day is recommended for grazing steers during the post-weaning period in the dry season of the year. 相似文献