55 research outputs found
Modelos para predizer exigências energéticas para codornas de corte
No full textThree assays were carried out with the purpose of studying the energetic metabolism of meat quails, through the determination of energetic requirements for weight maintenance and gaining, and the efficiency of recovery and deposition of energy such as fat and protein, formulating and proposing prediction equations of requirements of metabolizable energy for meat quails. In the Assay 1, it has been used 80 meat quails with 35 day old, housed in metabolism cages and distributed on a completely randomized design (CRD) with 4 treatments (ad libitum intake, 70, 50 and 30% of ad libitum intake) and 5 replicates each. The feed was formulated to supply the nutritional requirements for birds of that age. The values of intake and excreted gioss energy were determined and considering the balance of nitrogen it has been verified, in fresh matter, the apparent metabolizable energy corrected by nitrogen balance (AMEn) of the feed. The average values of AMEn were: 2.951 Kcal/kg, 2.907 kcal/kg, 2.898 kcal/kg and 3.162 kcal/kg respectively for treatments of ad libitum intake, 70, 50 and 30% of the ad libitum intake. In the Assay II, it has been used 620 non-sexed meat quails, on 15 days of age, distributed on a completely randomized design (CRD), with four treatments and five replicates, totaling 20 experimental units, with 31 birds each. The treatments consisted on ad libitum intake, 70, 50 and 30% of ad libitum intake, being the food intake quantified daily. Slaughters were carried out on 15 and 35 days old, using the comparative slaughter tecbnique by factorial design. The retained body energy (REc), heat production (HP) and metabolizable energy intake (MEl), were quantified regarding the metabolic weight of the birds. Using regression analysis of these variables it has been obtained the demands values of metabolizable energy of maintenance (MEm = 157.61 kcal/kg°/75/day), net energy of maintenance (NEm = 74.17 kcal/kg°/75/day), and also the efficiency of energy use (k). The respective values for total efficiency of energy use (Kgp), efficiency of maintenance (Km) and efficiency for fat deposition (Kg) and crude protein (Kp) were 0.47, 0.47, 0.79, 0.32. In the Assay III, it has been used 550 and 500 birds, respectively for the experimental lst phase (1 to 14 days) and experimental 2nd phase (15 to 35 days). The experimental design was entirely randomized (CRD), with 10 experimental units (box) of 55 birds (1 st phase) and 50 birds (2nd phase). Each two experimental units was a repetition, totalizing five replicates, where the birds were fed with a feed formulated according with their requirements on each phase. The slaughters were performed weekly, and through the regression of energy content in the carcass by the body weight, it was determined the requirement of net energy for weight gain, which was divided by the ME efficiency uses of diet (Assay II) provided the requirement of metabolizable energy for gain weight (MEg). The obtained values of MEg for the lst and 2nd phase were, respectively: 2.91 and 4.5 kcal/g. Determined the values of MEm and MEG, it has been proposed the prediction equations of the energetic requirements for meat quails in the period from 1 to 14 and from 15 to 35 days of age respectively: MEl = 157.61W°75 + 2.91G and MEl = 157.61W°75 + 4.5G.Foram conduzidos três ensaios com o objetivo de estudar o metabolismo energético de codornas de corte, por meio da determinação das exigências energéticas para manutenção e ganho de peso, além das eficiências de aproveitamento e deposição de energia como gordura e proteína, para elaborar equações de predição das exigências de energia metabolizável para codornas de corte. O primeiro ensaio foi conduzido para determinar a energia metabolizável (EM) das rações. Foram utilizadas 80 codornas de corte com 35 dias de idade, alojadas em gaiolas de metabolismo e distribuídas num delineamento inteiramente casualizado (DIC) com quatro tratamentos (consumo ad libitum, 70, 50 e 30% do consumo ad libitum) e cinco repetições cada. A ração foi formulada para atender as exigências nutricionais das aves para aquela idade. Os valores de energia bruta ingerida e excretada foram determinados e considerando o balanço de nitrogênio verificou-se, na matéria natural, a energia metabolizável aparente corrigida pelo balanço de nitrogênio (EMAn) da ração. Os valores médios de EMAn obtidos, foram: 2.951 Kcal/kg, 2.907 kcal/kg, 2.898 kcal/kg e 3.162 kcal/kg respectivamente para os tratamentos de consumo ad libitum, 70, 50 e 30% do consumo ad libitum. O segundo ensaio teve o objetivo de determinar a exigência de EM de mantença. Foram utilizadas 620 codornas de corte não sexadas, aos 15 dias de idade, distribuídas em um delineamento inteiramente casualizado (DIC), com quatro tratamentos e cinco repetições, totalizando 20 unidades experimentais, com 31 aves cada. Os tratamentos consistiram em consumo ad libitum, 70, 50 e 30% do consumo ad libitum, sendo a ingestão de alimento quantificada diariamente. Foram realizados abates referenciais aos 15 e aos 35 dias de idade, utilizando a técnica de abate comparativo. A energia retida corporal (ERc), produção de calor (PC) e ingestão de energia metabolizável (EMI), foram quantificadas considerando o peso metabólico das aves. Utilizando de análises de regressão dessas variáveis foram obtidos os valores da exigência de energia metabolizável de mantença (EMm = 157,61 kcal/kg°/75/dia), energia líquida de mantença (ELm 74,17 kcal/kg°/75/dia), e também as eficiências de utilização de energia (k). Os valores respectivos para a eficiência total de utilização de energia (Kgp), eficiência para mantença (Km) e eficiências para deposição de gordura (Kg) e proteína bruta (Kp) foram de 0,47, 0,47, 0,79, 0,32. O terceiro ensaio teve o objetivo de determinar as exigências para ganho de peso. Foram utilizadas 550 e 500 aves respectivamente para ia fase (1 a 14 dias) e 2 fase (15 a 35 dias) experimental. O delineamento experimental foi inteiramente casualizado (DIC), com 10 unidades experimentais (box) de 55 aves (1 fase) e 50 aves (2 fase) cada. A cada duas unidades experimentais compreendeu uma repetição, totalizando assim, cinco repetições, em que as aves foram alimentadas com uma ração basal formulada para atender as exigências em cada fase. Os abates foram realizados semanalmente e através da regressão do teor de energia na carcaça em função do peso corporal foi determinada a exigência de energia líquida para ganho de peso, que dividida pela eficiência de utilização da EM da dieta (Ensaio II) obteve-se a exigência de energia metabolizável para ganho de peso (EMg). Os valores de EMg obtidos para P e 2a fase foram respectivamente: 2,91 e 4,5 kcal/g. Determinados os valores de EMm e EMg foram propostas as equações de predição das exigências energéticas para codornas de corte no período de 1 a 14.xvi, 46 [1]
Modelos para predizer exigências energéticas para codornas de corte
No full textThree assays were carried out with the purpose of studying the energetic metabolism of meat quails, through the determination of energetic requirements for weight maintenance and gaining, and the efficiency of recovery and deposition of energy such as fat and protein, formulating and proposing prediction equations of requirements of metabolizable energy for meat quails. In the Assay 1, it has been used 80 meat quails with 35 day old, housed in metabolism cages and distributed on a completely randomized design (CRD) with 4 treatments (ad libitum intake, 70, 50 and 30% of ad libitum intake) and 5 replicates each. The feed was formulated to supply the nutritional requirements for birds of that age. The values of intake and excreted gioss energy were determined and considering the balance of nitrogen it has been verified, in fresh matter, the apparent metabolizable energy corrected by nitrogen balance (AMEn) of the feed. The average values of AMEn were: 2.951 Kcal/kg, 2.907 kcal/kg, 2.898 kcal/kg and 3.162 kcal/kg respectively for treatments of ad libitum intake, 70, 50 and 30% of the ad libitum intake. In the Assay II, it has been used 620 non-sexed meat quails, on 15 days of age, distributed on a completely randomized design (CRD), with four treatments and five replicates, totaling 20 experimental units, with 31 birds each. The treatments consisted on ad libitum intake, 70, 50 and 30% of ad libitum intake, being the food intake quantified daily. Slaughters were carried out on 15 and 35 days old, using the comparative slaughter tecbnique by factorial design. The retained body energy (REc), heat production (HP) and metabolizable energy intake (MEl), were quantified regarding the metabolic weight of the birds. Using regression analysis of these variables it has been obtained the demands values of metabolizable energy of maintenance (MEm = 157.61 kcal/kg°/75/day), net energy of maintenance (NEm = 74.17 kcal/kg°/75/day), and also the efficiency of energy use (k). The respective values for total efficiency of energy use (Kgp), efficiency of maintenance (Km) and efficiency for fat deposition (Kg) and crude protein (Kp) were 0.47, 0.47, 0.79, 0.32. In the Assay III, it has been used 550 and 500 birds, respectively for the experimental lst phase (1 to 14 days) and experimental 2nd phase (15 to 35 days). The experimental design was entirely randomized (CRD), with 10 experimental units (box) of 55 birds (1 st phase) and 50 birds (2nd phase). Each two experimental units was a repetition, totalizing five replicates, where the birds were fed with a feed formulated according with their requirements on each phase. The slaughters were performed weekly, and through the regression of energy content in the carcass by the body weight, it was determined the requirement of net energy for weight gain, which was divided by the ME efficiency uses of diet (Assay II) provided the requirement of metabolizable energy for gain weight (MEg). The obtained values of MEg for the lst and 2nd phase were, respectively: 2.91 and 4.5 kcal/g. Determined the values of MEm and MEG, it has been proposed the prediction equations of the energetic requirements for meat quails in the period from 1 to 14 and from 15 to 35 days of age respectively: MEl = 157.61W°75 + 2.91G and MEl = 157.61W°75 + 4.5G.Foram conduzidos três ensaios com o objetivo de estudar o metabolismo energético de codornas de corte, por meio da determinação das exigências energéticas para manutenção e ganho de peso, além das eficiências de aproveitamento e deposição de energia como gordura e proteína, para elaborar equações de predição das exigências de energia metabolizável para codornas de corte. O primeiro ensaio foi conduzido para determinar a energia metabolizável (EM) das rações. Foram utilizadas 80 codornas de corte com 35 dias de idade, alojadas em gaiolas de metabolismo e distribuídas num delineamento inteiramente casualizado (DIC) com quatro tratamentos (consumo ad libitum, 70, 50 e 30% do consumo ad libitum) e cinco repetições cada. A ração foi formulada para atender as exigências nutricionais das aves para aquela idade. Os valores de energia bruta ingerida e excretada foram determinados e considerando o balanço de nitrogênio verificou-se, na matéria natural, a energia metabolizável aparente corrigida pelo balanço de nitrogênio (EMAn) da ração. Os valores médios de EMAn obtidos, foram: 2.951 Kcal/kg, 2.907 kcal/kg, 2.898 kcal/kg e 3.162 kcal/kg respectivamente para os tratamentos de consumo ad libitum, 70, 50 e 30% do consumo ad libitum. O segundo ensaio teve o objetivo de determinar a exigência de EM de mantença. Foram utilizadas 620 codornas de corte não sexadas, aos 15 dias de idade, distribuídas em um delineamento inteiramente casualizado (DIC), com quatro tratamentos e cinco repetições, totalizando 20 unidades experimentais, com 31 aves cada. Os tratamentos consistiram em consumo ad libitum, 70, 50 e 30% do consumo ad libitum, sendo a ingestão de alimento quantificada diariamente. Foram realizados abates referenciais aos 15 e aos 35 dias de idade, utilizando a técnica de abate comparativo. A energia retida corporal (ERc), produção de calor (PC) e ingestão de energia metabolizável (EMI), foram quantificadas considerando o peso metabólico das aves. Utilizando de análises de regressão dessas variáveis foram obtidos os valores da exigência de energia metabolizável de mantença (EMm = 157,61 kcal/kg°/75/dia), energia líquida de mantença (ELm 74,17 kcal/kg°/75/dia), e também as eficiências de utilização de energia (k). Os valores respectivos para a eficiência total de utilização de energia (Kgp), eficiência para mantença (Km) e eficiências para deposição de gordura (Kg) e proteína bruta (Kp) foram de 0,47, 0,47, 0,79, 0,32. O terceiro ensaio teve o objetivo de determinar as exigências para ganho de peso. Foram utilizadas 550 e 500 aves respectivamente para ia fase (1 a 14 dias) e 2 fase (15 a 35 dias) experimental. O delineamento experimental foi inteiramente casualizado (DIC), com 10 unidades experimentais (box) de 55 aves (1 fase) e 50 aves (2 fase) cada. A cada duas unidades experimentais compreendeu uma repetição, totalizando assim, cinco repetições, em que as aves foram alimentadas com uma ração basal formulada para atender as exigências em cada fase. Os abates foram realizados semanalmente e através da regressão do teor de energia na carcaça em função do peso corporal foi determinada a exigência de energia líquida para ganho de peso, que dividida pela eficiência de utilização da EM da dieta (Ensaio II) obteve-se a exigência de energia metabolizável para ganho de peso (EMg). Os valores de EMg obtidos para P e 2a fase foram respectivamente: 2,91 e 4,5 kcal/g. Determinados os valores de EMm e EMg foram propostas as equações de predição das exigências energéticas para codornas de corte no período de 1 a 14.xvi, 46 [1]
Vitamin K supplementation for meat quail in growth of 1 to 14 days old
No full textThe experiment was carried outto determine the levels of vitamin K for meat quails (Coturnixcoturnixsp) from 1 to 14 days of age. Atotal of 2200 birds were used, complete by random experimental design, with 8 treatments, 5 repetitions and 55 meat quails per experimental unit. The levels of vitamin K supplementation were 0; 0.7; 1.0; 1.3; 1.6; 1.9; 2.2; 2.5 mg/kg diets. The performance was measured through weighing weekly from the birds and feed, and at the end of the experiment was carried out collects blood and bones for the assessment of bone quality parameters. The levels of vitamin K supplementation had no influence on performance orbone quality, except thatthe bone density and calcium concentration of the femur and the bone density of the tibia showeda quadratic effect, with estimates of 0.98; 0.92 and 1.18 respectively. The length of the tibia showed a linear increase according to the levels of vitamin K. There was no effect in the concentration of serum calcium, but there was a quadratic effect in the concentration of alkaline phosphatase. The vitamin K supplementation did not affect the performance of the meat quails from 1 to 14 days of age, showing that the amount of vitamin K present in ground corn and soybean meal-based diets is sufficient to meet the needs of the birds’ performance.</p
Control of soybean anthracnosis with potassium leaf applicattion
No full textO manejo de doenças é essencial à produtividade agrícola. O objetivo desse estudo foi avaliar a utilização de potássio aplicado via foliar no controle da antracnose da soja. O experimento foi realizado na Universidade Estadual de Mato Grosso do Sul, unidade de Aquidauana, no laboratório de Fitossanidade (Fitossan-AQ), em casa de vegetação. Utilizou-se as cultivares Nidera NS 6700 IPRO e Monsoy M6410 IPRO. Foram utilizados os indutores K₂SiO₃ e KCl nas cinco doses: 0; 1,31; 2,62; 5,24 e 10,48 g L-¹ de K₂O. O isolado de C. truncatum foi obtido de plantas de soja na safra 2020/2021 em Aquidauana e cultivado em meio BDA. A inoculação foi realizada 24 horas após a aplicação dos indutores, no estádio vegetativo V3, com suspensão de esporos 1,6 x 10⁶ conídios mL-¹, aplicada na face adaxial do segundo trifólio. Foram avaliadas a fitotoxicidade aos 7 dias, notas de severidade aos 7 e 12 dias e área da doença aos 12 dias. O delineamento foi inteiramente casualizado (DIC), em esquema fatorial (2x2x5), com 20 tratamentos e 5 repetições. As variáveis fitotoxicidade e notas de severidade foram analisadas utilizando Kruskal-Wallis e Dunn 5%. A área da doença foi submetida a uma ANOVA, com interação significativa sendo realizado ajustes de regressões polinomiais. A maior fitotoxicidade foi registrada com o indutor na dose de 10,48 g L-¹ de K₂O, com nota 5 para K₂SiO₃ e nota 4,8 no KCL. As menores notas de severidade aos 7 dias foram constatadas utilizando K₂SiO₃ nas doses de 1,31 e 2,62 g L-¹ de K₂O na MS6410 IPRO notas 1,4 e 1,0 respectivamente e em NS 6700 IPRO na dose 1,31 g L-¹ de K₂O, nota 2,2. Aos 12 dias, a maior fitotoxicidade manteve-se nas doses mais altas, enquanto as menores notas de severidade foram constatadas nas doses 1,31 e 2,62 g L-¹ de K₂O. Na avaliação da área da doença na cultivar M6410 IPRO, as doses ideais foram 1,31 g L-¹ de K₂O de KCl com 5,67% de severidade e 2,64 g L-¹ de K₂O no K₂SiO₃ com severidade de 12,76%. Na NS 6700 IPRO, as mesmas doses resultaram em severidades de 6,5% no KCl e 9,2% em K₂SiO₃. Conclui-se que os indutores são capazes induzir a resistência nas doses mais eficientes no controle da antracnose para ambos os indutores são de 1,31 a 2,62 g L-¹ de K₂O, esses valores também estão associados a menor fitotoxicidade nas plantas de soja.The maintenance of the plants\u27 productive potential could be guaranteed through disease management. The objective of the experiment was to evaluate a foliar application of potassium in reducing the severity of soybean anthracnose. Two potassium sources were evaluated: Potassium Silicate and Potassium Chloride, and five doses, in two soybean cultivars (M6410 IPRO; NS6700 IPRO). Two sources of Potassium were evaluated: K2SiO3 (Quimifol Silicon 131 g.L-1 of K2O) and Potassium Chloride (KCl P.A. 99.5%) at doses 0; 1.31; 2.62 1; 5.24; 10.48 g L-1 in K2O equivalent. Phytotoxicity was evaluated at seven days after inoculation, severity on a grading scale at 7 and 12 days after inoculation and an area of disease at 12 days. The phytotoxicity and severity score variables were submitted to Kruskal-Wallis and Dunn 5% analysis and a variable area of the disease was submitted to ANOVA. Thus, for significant hospitalization among those adopted, polynomial regression equations were adjusted for each K source applied to each cultivar. The use of K2O, having potassium silicate and potassium chloride as sources, informed via the leaves, induces the severity of anthracnose in soybean cultivars, however, high doses of phytotoxicity in the plants
PhoNeS: A novel approach to BNCT with conventional radiotherapy accelerators
No full textPhoNeS (Photo Neutron Source) is an INFN project devoted to the optimization of the neutron production and moderation in radiotherapy linear accelerators. LinAcs producing high energy (15-25 MeV) photon beams are becoming widespread. At this energy neutron photo-production is unavoidable and the neutron dose must be controlled and reduced during normal radiotherapy. A technique known as BNCT (Boron Neutron Capture Therapy) uses neutrons for radiotherapic treatments: the cells are given a drug containing 10B which undergoes fission after neutron capture, inducing heavy damages to the DNA of the cell itself. This paper will describe the moderator developed by PhoNeS and the results in terms of neutron flux and spectrum and photon contamination of the measurements performed on several radiotherapy accelerators
The climatic significance of laminated sediments from turbid meltwaters on the NW Barents Sea continental margin (Arctic)
No full textThe recent depositional architecture of the north-western Barents Sea continental margin derives from past
climate changes with alternating deposition of highly consolidated glacigenic diamicton (continental shelf)
and debris flows (continental slope). These are associated to shelf-edge glaciations, and low-density, normally
consolidated biogenic-rich sediments deposited during interglacial conditions. In addition, sub-bottom records
outline the presence of acoustically laminated deposits locally having thickness exceeding 10 m, which lithofacies
characteristics indicating deposition from turbid meltwaters (plumites) during short-living, phases of glacial
retreat (meltwater pulses, MWP). One of the youngest stratigraphic intervals recognized along the NW Barents
Sea margin was related to the MWP-1a that was responsible for the deposition of about 1.1 x 1011 tonnes of
sediments on the upper slope of the Storfjorden-Kveithola TMFs (south of Svalbard) (Lucchi et al., 2015). New
compositional analyses of such plumites revealed a distinct signature that allow us to distinguish deposition from
glacial melting from that related to the ice-sheet sub-glacial erosion and transport to the edge of margins. Sediment
facies and compositional analyses lead to a new climate-related interpretation of the laminated deposits recognized
during Marine Isotopic Stages 3 and 2 on the NW margin of the Barents Sea, including Heinrich Event H2
A Imunidade Jurisdicional dos Estados em casos de graves violações dos Direitos Humanos: o caso Alemanha v. Itália pela Corte Internacional de Justiça e seus desdobramentos no Direito Internacional
No full textTCC(graduação) - Universidade Federal de Santa Catarina. Centro de Ciências Jurídicas. Direito.O cotejo entre o direito internacional e o direito interno sempre foi fonte de alongadas e frutíferas discussões dentre os internacionalistas. Na dinâmica deste enfrentamento, o Princípio da Imunidade Jurisdicional dos Estados enlaça-se virginalmente à soberania, à igualdade destes sujeitos e à concepção que cada Estado tem em relação ao alcance das normas que concebeu dentro de suas fronteiras e às quais aderiu em virtude da sua convivência com outros entes perante a comunidade internacional. Dado tal panorama, neste trabalho objetiva-se analisar sentença lavrada pela Corte Internacional de Justiça em que litigaram Alemanha e Itália. Em síntese, a Corte de Cassação Italiana condenou em diferentes oportunidades o Estado Alemão a indenizar vítimas de graves violações de Direitos Humanos perpetradas pelo Reich em território italiano no transcurso da 2ª Guerra Mundial, dentre as quais estão o envio de cidadãos a campos de concentração e o desrespeito à condição de prisioneiros de guerra a membros das forças armadas italianas. Por consequência, a Alemanha buscou guarida na CIJ para ter seu direito à imunidade jurisdicional garantido. Logo, a proposta apresentada cuida da seguinte interrogação: seria possível questionar a aplicação da Imunidade Jurisdicional dos Estados em casos de graves violações dos Direitos Humanos no âmbito do ordenamento jurídico internacional, a partir dos subsídios constantes na sentença exarada pela CIJ no caso Alemanha v. Itália? A estrutura do trabalho trata, em um primeiro momento, do histórico desde a concepção de soberania nos Estados modernos (Paz da Westphalia) até a atual noção de imunidade relativa. Ao segundo capítulo foi relegada a função de conceituar a imunidade e o jus cogens de acordo com a visão dos doutrinadores contemporâneos. Por fim, no terceiro capítulo há análise específica sentença e seu paralelo com jurisprudência, legislação e doutrina internacionais.The comparison between international law and national law has always been a source of lengthy and fruitful discussions among the internationalists. In this confrontational dynamic, the jurisdictional immunity of states principle entangles virginally to sovereignty, to equality and to the perception that every state has towards the rules it has conceived within its own borders and to which it has acceded into force due to its co-existence along with other entities before the international community. Given this situation, the primary goal is to analyze the judgment written by the International Court of Justice in which Germany and Italy have litigated. In short, on different occasions, the Italian Court of Cassation condemned the German State to indemnify the victims from gross violations of humanitarian law that were perpetrated by the Reich within Italian territory during the 2nd World War, among which stand the displacing of citizens to concentration camps and the vile conditions that the war prisoners had to endure. As a result, Germany sought legal help at the ICJ to assure its right to immunity. Therefore, the proposal presented in this work refers to the following question: would it be possible to wrangle the application of the jurisdictional immunity of the States in cases of serious violations of human rights at the international legal framework from the subsidies present on the judgment of Germany v. Italy? At first, the structure of this work deals with the historical events from the conception of sovereignty in the modern States (Peace of Westphalia) to the current notion of restrictive immunity. The second chapter was relegated to conceptualize the immunity according to the view of contemporary scholars. Finally, in the third chapter there is a specific analysis of the judgment and its parallel with the jurisprudence, the legislation and the international doctrine
BURSTER: BOTTOM CURRENTS IN A STAGNANT ENVIRONMENT
No full textThe glacigenic Kveithola Trough is an abrupt and narrow (100 km-long and 13 kmwide) sedimentary system located in the NW Barents Sea (Rebesco et al., 2011; Ruther et al., 2012; Bjarnadóttir et al., 2013). Along with the larger Storfjorden glacial system, it hosted, during the last glaciation, ice streams draining ice from the southern Svalbard in the north and Bear Island in the south (Andreassen et al., 2008; Pedrosa et al., 2011). During the CORIBAR Cruise on board RV Maria S. Merian (16.07. - 15.08.2013; Tromsø - Tromsø) a wealth of geophysical data including PARASOUND sub-bottom profiles and multibeam, and sediment samples retrieved by gravity-, multi-, boxcorer, and the seafloor drill rig MeBo (Hanebuth et al., 2013) were collected on the Kveithola Drift, a complex morphological and depositional feature confined in the innermost part of the glacially-erode Kveithola Trough. The internal seismic reflections of the drift show a drastic thinning and termination towards the north. Here a distinct moat can be identified, which implies the strong influence of dense bottom currents, inferred to flow (or at least to have flown in the past) towards the outer shelf. The highly dynamic environment depicted from the morphological and structural characteristics of the sediment drift is in contrast with the sediment facies and preserved biota observed in surface sediments. The retrieved sediments have a strong smell of H2S and are mostly black, organic matter-rich, with abundant black worm tubes (Pogonophora worms), and occasionally with living reddish polychaetes (possibly ampharetid polychaetes). The recent and living benthic foraminiferal assemblage observed in the sediments is characterized by the presence of typically oxygen-depleted environmental taxa. Any bottom current-related sedimentary structure was observed on surface sediments. The Kveithola Drift that formed under persistent dense bottom currents appears today as a “stagnant environment” strongly affected by low-oxygen conditions with likely ongoing seep activity. The presence of an apparently stagnant, possibly chemosynthetic, environment in the sediment drift area of the inner Kveithola Through was an unexpected discovery. We therefore think it is of primary importance to better define the bio-geochemical and oceanographic characteristics of the inner area of the Kveithola Trough in order to better define this “anomalous” sedimentary system and to understand the local and global impact of this type of environment in terms of carbon cycle and the transfer of chemosynthetic-derived products to the deeper environments as consequence of regional oceanographic patterns.
The BURSTER project aims to investigate the geodynamic and hydrographic conditions, and the active gas seepage present in the pockmark-field piercing the sediment drift located in the inner part of the Kveithola Trough. The type of investigation is strongly multidisciplinary including physical and biological oceanography, water, sediment and gas geochemistry, micropaleontology, microbiology geophysics, and sedimentology. The investigations will be carried out within three working days with the aim of outlining the principal oceanographic, biological and geological aspects of the area on which building up further investigations
BURSTER - Bottom Currents in a Stagnant Environment. EUROFLEETS-2 Cruise Summary Report
No full textEurofleets 2- BURSTER cruise was conducted onboard the German icebreaker RV Polarstern (Expedition PS99-1a) during June 13–23, 2016 (Bremerhaven-Longyearbyen) having the principal objective of investigating the hydrographic and bio-geochemical conditions of the Kveithola glacial trough (south of Svalbard), and to uncover the possible existence of gas seepage activity in the area. Although the BURSTER research was intended as a preparatory study for the writing of a major research project, the amount of planned activities onboard was really ambitious.
Thanks to a tireless, enthusiastic group formed by 11 students out of 23 scientists, a Teacher at Sea (GIFT, EU programme), and a technician from a small-medium enterprise operating with a transportable electron microscope (Nanovision Srl,), 89 multi-cores (22.50 m of sediments and 830 sub-samples), 265 water samples, 28 CTD casts along 7 transects and 2.57 km of benthic camera survey (OFOS), were collected during only 48 hours. In addition, according to the project work program, 24 hours were dedicated to the maintenance/recovery of two moorings that were deployed west of Svalbard during the Eurofleets 2- PREPARED project (RV G.O. Sars, June 2014). BURSTER group was actively supported by 4 scientists of the Italian PNRA project DEFROST, 4 AWI scientists of expedition PS99-1 and the Chief scientist, T. Soltwedel.
The cruise successfully recovered evidences of chemosynthetic activity in the Kveithola Trough with the presence of benthic fauna and large tabular and/or irregular-shaped rocks that share the same characteristics of methanogenic environments observed in gas seepage areas. The promising preliminary results obtained from this initial survey of the area will represent the base for the writing of a major project for a detailed investigation of the microbial, biologic and oceanographic system of the Kveithola Trough
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