9 research outputs found
Nutrient extraction and export by fully irrigated sugarcane varieties
A pesquisa tecnológica para suporte do setor sucroalcooleiro nacional mostra que são esporádicos os trabalhos desenvolvidos com cana-de-açúcar irrigada envolvendo a exigência nutricional. Nesse contexto, objetivou-se quantificar, durante o ciclo de cana-planta de 11 variedades de cana-de-açúcar (SP79-1011, RB813804, RB863129, RB872552, RB943365, RB72454, RB763710, SP78-4764, SP81-3250, RB867515 e RB92579) cultivadas sob irrigação plena, a capacidade de extração e exportação de N, P, K, Ca e Mg, bem como a exigência nutricional para produção de uma tonelada de colmo por hectare (TCH). A pesquisa foi realizada em campo, no município de Carpina, PE, durante a safra agrícola 2006/2007. O delineamento experimental empregado foi de blocos casualizados, com 11 tratamentos e quatro repetições. A extração e exportação de nutrientes, assim como a exigência nutricional, foram avaliadas aos 360 dias após o plantio (DAP) na parte aérea das plantas. A extração de nutrientes na parte aérea da cana-planta apresentou, em média, valores de 179, 25, 325, 226 e 87 kg ha-1 de N, P, K, Ca e Mg, respectivamente, o que proporcionou a seguinte ordem decrescente de extração: K > Ca > N > Mg > P. A exportação média de N, P, K, Ca e Mg pelo colmo das variedades irrigadas foi de 92; 15; 188; 187; e 66 kg ha-1; correspondendo, respectivamente, a 51, 60, 58, 83 e 76 % de todo o nutriente extraído na parte aérea da cana-planta, com destaque para as variedades RB92579 e SP81-3250 para o N, RB813804, RB863129, RB872552, RB763710, RB92579, SP78-4764, SP81-3250 e SP79-1011 para o P, SP79-1011, SP81-3250, RB813804, RB872552 e RB763710 para o K, RB92579 e RB863129 para o Ca e RB92579 para o Mg. Para produção de uma TCH, foram exigidos pelas variedades durante o ciclo de cana-planta valores médios de 0,91; 0,13; 1,71; 1,18; e 0,44 kg de N, P, K, Ca e Mg, respectivamente.A review of technology research supporting the Brazilian sugaralcohol sector shows that only sporadic studies with irrigated sugarcane have been developed to investigate nutritional requirements. In this context, the objective of this study was to quantify the capacity of extraction and export of N, P, K, Ca, and Mg as well as the nutritional requirement for the production of one ton of stalk per hectare (TCH) in the plant cane cycle of 11 sugarcane varieties (SP79-1011, RB813804, RB863129, RB872552, RB943365, RB72454, RB763710, SP78-4764, SP81-3250, RB867515, and RB92579) grown under full irrigation. The research was conducted under field conditions in the municipality of Carpina, PE, in the 2006/2007 growing season. The experiment was arranged in a randomized block design with 11 treatments and four replications. Nutrient extraction and export as well as nutritional requirements of the shoot components of the plants were evaluated 360 days after planting. The mean nutrient accumulation in shoots was 179, 25, 325, 226, and 87 kg ha-1 of N, P, K, Ca, and Mg, respectively.The average export of N, P, K, Ca, and Mg via stalks of the irrigated varieties was 92, 15, 188, 187, and 66 kg ha-1; corresponding, respectively, to 51, 60, 58, 83, and 76 % of the whole nutrient amount taken up by the cane plant. The extracted nutrient amounts were highest by the following varieties: RB92579 and SP81-3250 for N; RB813804, RB863129, RB872552, RB763710, RB92579 SP78-4764, SP81-3250 and SP79-1011 for P; SP79-1011, SP81-3250, RB813804, RB872552 and RB763710 for K; RB92579 and RB863129 for Ca; and RB92579 for Mg, for which the export values in stalks were highest. For the production of one TCH, the varieties needed 0.91, 0.13, 1.71, 1.18, and 0.44 kg of N, P, K, Ca, and Mg, respectively
Extração e exportação de nutrientes por variedades de cana-de-açúcar cultivadas sob irrigação plena
Pervasive gaps in Amazonian ecological research
Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4
While the increasing availability of global databases on ecological communities has advanced our knowledge
of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In
the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of
Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus
crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced
environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian
Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by
2050. This means that unless we take immediate action, we will not be able to establish their current status,
much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio
Pervasive gaps in Amazonian ecological research
Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost
ADUBAÇÃO FOSFATADA EM CANA PLANTA E SOCA EM ARGISSOLOS DO NORDESTE DE DIFERENTES TEXTURAS
The present work studied the productivity of plant and ratoon cane in soils with different physical, chemical and mineralogical particulars submitted to phosphate fertilization. Randomized block field experi- ments were located at Japungu Distillery (Paraíba State), at Sugar Cane Experimental Station of Carpina (Pernambuco State) and at Bom Jesus Sugar Cane plant (Pernambuco State), from where Argisoils of sandy, mid and clayey textures were selected respectively. The doses of 0, 40, 80, 120, 160 and 200 kg ha - 1 P 2 O 5 were applied at the bottom of the furrow (fertilization foundation). In the subsequent ratoon cane were applied 0 and 40 kg ha - 1 P 2 O 5 (topdressing) for each of the doses applied at the planting. It was concluded in this study that the productivity of sugarcane plant was positively influenced by phosphorus fertilization planting. The ratoon cane only responded nicely to phosphorus coverage in the less weathered medium texture Argisoils; Phospho- rus fertilization of ratoon sugarcane coverage in clay and weathered Argissolos did not promote increased productivity, restricting its recommendation in Argissolos with these characteristics
Prevalência de dentes supranumerários em pacientes atendidos no Hospital Universitário da UFPI: um estudo retrospectivo de cinco anos
INTRODUÇÃO: Variações no desenvolvimento dentário podem implicar em alterações no número de dentes, como, por exemplo, a hiperdontia, que é caracterizada pela formação de dentes em excesso, que são chamados de supranumerários. Sua ocorrência está frequentemente associada a patologias e interferências na erupção dos dentes permanentes, que podem comprometer a estética e a oclusão. Portanto, é importante descrever seu perfil epidemiológico. OBJETIVO:Este estudo objetivou analisar dados epidemiológicos, em prontuários, avaliando a prevalência dos dentes supranumerários. MATERIAL E MÉTODO: A amostra constituiu-se de 1511 prontuários de pacientes atendidos no Hospital Universitário da Universidade Federal do Piauí, entre janeiro de 2006 e janeiro de 2011, observando-se a prevalência dos dentes supranumerários segundo número de pacientes, gênero, faixa etária, cor da pele, localização, posição no arco dentário, tipo e tratamento. RESULTADO: A prevalência dos dentes supranumerários foi de 1,99%, ocorrendo em pacientes de cor parda (78,57%), com dentição permanente (86,96%), do gênero masculino (53,33%), localizados em região posterior de maxila (35%) e mandíbula (35%), e do tipo paramolar (38,10%). A maioria das cirurgias foi realizada por indicação ortodôntica (62,96% dos casos). CONCLUSÃO: De acordo com os resultados, a presença de dentes supranumerários foi um achado incomum com predominância pela maxila, sendo o tipo paramolar o mais frequente. Todos os casos foram tratados por remoção cirúrgica, sendo a maioria por indicação ortodôntica