Distribution and fractionation of the rare earth elements in Brazilian soils

The distribution and fractionation of Sc, Y and 14 rare earth elements (La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu) were investigated in 144 samples (topsoil and subsoil) from 88 sites distributed across Brazil. Although, a wide range of natural variability in REE content was observed, overall the REE median contents were relatively low compared with those reported in soils from other parts of the world. The REE contents in Brazilian soils showed significant correlation mainly with Fe, Mn and Ti oxides, as well as organic matter. REE distribution in soils basically depend on the parent material, while fractionation of individual REEs depend on soil characteristics that are partly influenced by pedogenic process. Soils developed from alkaline igneous rocks showed the highest average content of REEs followed by sedimentary rocks, unconsolidated clay sediments, metamorphic rocks, basic igneous rocks, unconsolidated sand and silt sediments, and acid igneous rocks. REE normalized patterns varied significantly within each geological formation, except for soils derived from alkaline igneous rocks. The greatest variations were observed in the light REEs. Graphic inspection using exploratory data analysis tools such as Q–Q normal plots and boxplots was effective to recognize patterns and identify different data groups, determine threshold values and thus define the range of the background REE variability. The data set generated in this study may be used as a preliminary reference for regulatory actions in the Brazilian environmental legislation

Desempenho e características de carcaça de cordeiros alimentados com dietas contendo alta proporção de concentrado adicionadas de agentes tamponantes Performance and carcass characteristics of feedlot lambs fed high grain diets with buffer compounds

Objetivou-se com este estudo avaliar os efeitos da adição de bicarbonato de sódio ou de fontes de calcário com diferentes granulometrias na ração, associadas ou não a monensina sódica, sobre o desempenho e as características de carcaça de cordeiros confinados recebendo dietas contendo alta proporção de concentrado. Quarenta e dois cordeiros Santa Inês com peso inicial de 21 ± 3 kg e 88 ± 5 dias de idade foram distribuídos em blocos completos casualizados em arranjo fatorial 2 &#215; 3, com seis tratamentos e sete repetições. Os animais foram alimentados com rações contendo 90% de concentrado, 10% de feno de "coastcross", uma fonte de calcário (calcário calcítico ou calcário calcítico tipo filler) ou bicarbonato de sódio (NaHCO3), com ou sem adição de monensina sódica (30 mg/kg da MS). Não foi observada influência dos agentes tamponantes no consumo de matéria seca e no ganho de peso médio diário. Entretanto, a conversão alimentar dos animais alimentados com as rações contendo monensina sódica (3,32 kg MS/kg de ganho) foi melhor que naqueles que consumiram as rações sem esse aditivo (3,58 kg MS/kg de ganho). Não houve efeito dos agentes tamponantes nos parâmetros de carcaça avaliados, observando-se valores médios de 50,4%; 2,4%; 13,9 cm² e 1,9 mm para o rendimento de carcaça quente, a perda por resfriamento, a área de olho-de-lombo e a espessura de gordura, respectivamente. A adição de monensina melhora a conversão alimentar e pode aumentar a rentabilidade do sistema de produção de cordeiros confinados.<br>The objective of this study was to assess the effects of adding sodium bicarbonate or limestone sources with different particle sizes to the diet, and their interaction with sodium monensin, on the performance and carcass characteristics of feedlot lambs fed fed high grain diets. Forty two Santa Ines lambs were used with 21 ± 3 kg initial average body weight and 88 ± 5 days old in feedlot, placed a randomized complete block design in a 2 &#215; 3 factorial arrangement with six treatments and seven replications. Animals were fed diet containing 90% concentrate, 10% "coastcross" hay, with one source of limestone (limestone or "filler" limestone) or sodium bicarbonate (NaHCO3), with or without monensin (30 mg/kg DM). No influence was observed of the buffering agents on dry matter intake or average daily gain. However, the feed conversion of the animals fed diet containing sodium monensin (3.34 kg DM/kg gain) was better than those fed diets containing monensin (3.32 kg DM/kg gain) compared to diets without monensin (3.58 kg DM/kg gain). There was no effect of the buffering agents on the carcass characteristics assessed: the mean values were 50.4%, 2.42%, 13.9 cm² and 1.9 mm hot carcass weight, chilling losses, longissimus muscle area and fat thickness, respectively. Adding monensin to the diet improves feed conversion and may make the feedlot lambs system more profitable