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GeoBioSciences GeoTechnologies and GeoEngineering
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Partial replacement of concentrate in the lactating ewe's diet with silages of agro-industrial by-products
Publication . Jerónimo, Eliana; Cachucho, Liliana; Alves, Helder; Guerreiro, Olinda; Paulos, Kátia; Costa, Cláudia; Costa, João; Gomes, Sandra; Alvarenga, Nuno; Alves, Susana P.; Bessa, Rui J. B.; Santos-Silva, José; Dentinho, Maria Teresa P.; GeoBioTec - Geobiociências, Geoengenharias e Geotecnologias; Elsevier BV
The purpose of this experiment was to evaluate the effect of partial replacement of concentrate feed with mixed ingredient silages (MIS) produced with agro-industrial by-products in the diets of lactating ewes on the body weight of ewes, growth performance of suckling lambs, composition and fatty acid (FA) profile of milk, and serum metabolites of the ewe. After lambing, 54 lactating ewes and their lambs were distributed to one of the following experimental diets (18 ewes/diet): C – concentrate diet; SPBG – concentrate and silage containing 200 g/kg sweet potato, 500 g/kg brewers grains and 300 g/kg alfalfa hay; and AHBG – concentrate and silage containing 200 g/kg almond hulls, 600 g/kg brewers grains and 200 g/kg alfalfa hay. Hay was provided ad libitum in all diets. In both silage diets (SPBG and AHBG) the concentrate and silage constitute 33.3 and 66.6 % DM of the diet, respectively. Every day, the ewes received the same amount of the diet, which was completely consumed. Lambs were weighed at birth and weekly during the 8 weeks of trial. In the last 4 weeks of the trial, individual milk samples were collected weekly and then pooled per each ewe for chemical analysis. At the end of the trial, a blood sample was collected from the ewes to analyse serum metabolites. SPBG and AHBG silage showed pH values of 4.00 and 4.29, respectively. Total N as NH3-N and as soluble-N varied from 3.23 to 5.23 and from 348 to 354 g/kg total N, respectively. The animals well accepted the silages. Partial replacement of concentrate with silage of agro-industrial by-products in lactating ewe diets did not affect the growth performance of suckling lambs and the composition of milk. Both silage dietary treatments changed the milk FA composition, reducing the short-chain FA (6:0–14:0), branched-chain FA, and 18:1 trans-10, and increasing the saturated FA 16:0, 18:0, 20:0, 22:0, 23:0 and 24:0 and 18:1 trans-11. Regarding serum metabolites, silage diets increased the urea concentration and decreased the β-hydroxybutyrate concentration. Results showed that ensiling is a good approach to preserving sweet potato, almond hulls, and brewers grains, producing a good quality feed that can be introduced to diets of lactating ewes without compromising animal performance.
Future Palaeontologists Will Detect Current Mammal Latitudinal Biodiversity Gradient
Publication . Galván, Sofía; Gamboa, Sara; Chiarenza, Alfio Alessandro; Rotatori, Filippo Maria; Oliver, Adriana; Varela, Sara; GeoBioTec - Geobiociências, Geoengenharias e Geotecnologias; Faculdade de Ciências e Tecnologia (FCT); Wiley-Blackwell
Aim: Fossil data provide crucial insights into past biogeographic and macroecological patterns. However, geological, biological, and sampling biases can potentially compromise genuine biodiversity inferences. Here, we tested whether fossil biases may hinder the accurate retrieval of the Latitudinal Biodiversity Gradient (LBG). Location: Global. Time Period: Contemporary. Major Taxa Studied: Mammals. Methods: We implemented a filtering process to current mammal distribution maps, simulating one geological, two biological, and three sampling sources of bias. Namely, distribution maps were downgraded to regions with sediments, species preservation was modulated by their range size and body size, and sampling was applied to locations with a fossil record. We applied the filters sequentially to mimic a process of progressive fossilisation, considering three preservation rates and removing up to 98.8% of the original species. We also applied filters independently to assess their individual effect. Lastly, we quantified the richness loss, the change in the slope between latitude and richness, and the change in richness maxima throughout the filters. Results: Results indicate that the applied filters collectively and distinctly influence the detection and robustness of the LBG signal. However, although the slope of the richness gradient diminishes progressively (especially for filters affecting species by their body size or taxonomic group), a LBG signal is detected across all the filters. Equally, despite the critical species loss, richness maxima remain around the equator. Main Conclusions: We demonstrated that strongly incomplete or biased samples can still recover accurate large-scale biogeographic patterns such as the LBG. Our results show an optimistic scenario in which, although the LBG intensity is sensitive to the uneven loss of information in biodiversity data, a detectable signal can be retrieved for all scenarios.
Almost sure convergence for weighted sums of pairwise PQD random variables
Publication . da Silva, João Lita; DM - Departamento de Matemática; GeoBioTec - Geobiociências, Geoengenharias e Geotecnologias; Taylor & Francis
We obtain strong laws of large numbers of Marcinkiewicz–Zygmund’s type for weighted sums of pairwise positively quadrant dependent random variables stochastically dominated by a random variable (Formula presented.) We use our results to establish the strong consistency of estimators which emerge from regression models having pairwise positively quadrant-dependent errors.
Os topónimos das ilhas atlânticas da Comunidade dos Países de Língua Portuguesa (CPLP) na história da Paleontologia
Publication . Rocha, Rogério Eduardo Bordalo da; Callapez, Pedro Miguel; Kullberg, José Carlos Ribeiro; Sá Caetano, Paulo do Carmo de; GeoBioTec - Geobiociências, Geoengenharias e Geotecnologias; DCT - Departamento de Ciências da Terra
O recurso a topónimos locais é de uso frequente na descrição científica de novas espécies. Numa perspetiva histórica da taxonomia paleontológica, estes enriquecem substancialmente a nomenclatura existente e permitem contextualizações geográficas mais efetivas. Desde meados do século XIX, os Açores, Madeira e Cabo Verde foram visitados por muitos naturalistas, os quais descreveram floras e faunas atuais e fósseis, usando frequentemente a toponímia local. Daí resultou, sobretudo, a descrição de mais de 60 novos táxones de invertebrados fósseis (ou “subfósseis”) do Cretácico Inferior ao Holocénico, para além de quatro vegetais, um cocolitoforídeo e um icnofóssíl, a partir de topónimos das ilhas atlânticas da Macaronésia da CPLP (Comunidade dos Países de Língua Portuguesa). Os mais utilizados foram Porto Santo (Madeira) (9), Madeira (6), Açores (6), Santa Maria (Açores) (5) e Cabo Verde (6), mas outros existem ligados a designações locais, como povoações e geoformas. Dado que muitos outros topónimos também têm servido para espécies atuais dos mesmos arquipélagos, incluindo São Tomé e Príncipe, e que as associações paleontológicas dos depósitos destas ilhas ainda carecem, em grande medida, de estudos aprofundados, é natural que parte destes táxones ainda venham a ser encontrados em novas jazidas, enriquecendo a presente lista. É interessante notar, também, que alguns dos nomes adotados não cumprem as regras do ICNZ (International Code of Zoological Nomenclature - Código Internacional de Nomenclatura Zoológica), necessitando de futura revisão.
Insights into the Spatial and Temporal Variability of Soil Attributes in Irrigated Farm Fields and Correlations with Management Practices
Publication . Tomaz, Alexandra; Martins, Inês; Catarino, Adriana; Mourinha, Clarisse; Dôres, José; Fabião, Marta; Boteta, Luís; Coutinho, João; Patanita, Manuel; Palma, Patrícia; GeoBioTec - Geobiociências, Geoengenharias e Geotecnologias; MDPI - Multidisciplinary Digital Publishing Institute
The evaluation of the spatial and temporal variability of soil properties can be valuable to improve crop productivity and soil health. A study of soil properties was carried out in southern Portugal, in three farm fields with irrigated annual crops (layers 0–20 cm and 20–40 cm), over three years. Factor Analysis (FA) and Discriminant Analysis (DA) were used to analyze the data. With FA, the observed variables were grouped into a smaller number of latent variables related to soil attributes. Discriminant Analysis was used to classify and identify the most dominant attributes and indicators for the time and space variability of soil parameters. The FA performed for the surface layer included factors related to texture, water and nutrient retention capacity, chemical composition, and soil fertility. In the sub-surface layer, the factor structure was similar, with four factors related to texture, chemical composition, nutrient availability, and soil fertility. The most influential factors and variables in temporal discrimination (sampling dates) in both layers were those related to chemical composition, with electric conductivity as the preponderant indicator. As for the spatial differentiation (fields), the dominant factor in the surface layer was texture, and in the sub-surface layer, nutrient availability. The most important discriminant indicators of spatial variability were fine sand proportion and available potassium, respectively, for the surface and sub-surface layers. The results obtained showed potential for the multidimensional and integrated assessment of patterns of temporal and spatial variation of soil functions from agricultural practices or soil degradation processes.
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Fundação para a Ciência e a Tecnologia
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6817 - DCRRNI ID
Número da atribuição
UIDB/04035/2020