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1.
Water Sci Technol ; 89(6): 1466-1481, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38557712

RESUMO

Floating treatment wetlands (FTWs) have the potential to improve the quality of wastewater discharges, yet design basics are unavailable to size these systems. This study investigates the effect of FTWs' coverage ratio and hydraulic retention time on agri-food wastewater treatment. This was studied in a pilot-scale experiment comprising four lagoons (6.5 m3 each) fed with real effluent from an existing tertiary treatment lagoon. An evaluation of FTW of different sizes (L24, L48, and L72 representing 24, 48, and 72% of pilot lagoons surface areas) and a control, L0 (without FTW), was performed over 16 months. Overall, L72 and L48 moderately improved total nitrogen (TN) mass removal compared to L0 (p < 0.05), while L24 exhibited similar TN mass removal (p = 0.196). The highest improvement was observed for L72, exhibiting up to 55% (mean of 13%) greater N mass removal than the control. The net increase in TN removal by FTWs was mainly related to denitrification, promoted by decreasing dissolved oxygen for increasing FTW coverage ratio. Residence time, temperature, and dissolved oxygen were the main parameters driving TN removal by FTWs. Retrofitting existing lagoons with FTW can facilitate N retrieval through plant harvesting, thereby reducing N remobilization from sediment (common in conventional lagoons).


Assuntos
Poluentes Químicos da Água , Áreas Alagadas , Eliminação de Resíduos Líquidos , Desnitrificação , Nitrogênio/análise , Poluentes Químicos da Água/análise , Oxigênio
2.
Data Brief ; 54: 110327, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38586128

RESUMO

This article describes data on eco-shrimp farming households in Ca Mau, Vietnam. The survey was conducted in Tam Giang Dong commune, Nam Can district, Ca Mau province from March 2023 to May 2023 with a total of 120 households engaged in eco-shrimp farming. The non-probability convenience sampling method was used to select respondents. Two responses were removed from the dataset due to uncomplete questionnaires. The dataset includes a structured questionnaire with 52 questions, along with a raw data file of 118 responses. The questionnaire collected data on (a) household demographic information, (b) eco-shrimp farming area and pond types, (c) production characteristics for the 2021-2022 eco-shrimp crop, and (d) farmers' perspectives on the eco-shrimp farming model. The dataset is available in an Excel file format. It is expected to benefit policymakers and local authorities by providing evidence-based insights into the eco-shrimp production model and the compliance of eco-shrimp farmers with mangrove conservation policies.

3.
Clin Anat ; 36(6): 926-936, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37272199

RESUMO

Our study aimed to evaluate the hip joints of healthy children aged 2-13 years morphometrically through radiographic images. Demographic characteristics of 300 healthy children in our study include an average age of 6.4 years old based on the 2-to-13-year-old bracket and sex classified to 133 girls and 167 boys. A total of 600 normal hips from these children were digitally measured based on Acetabular Index, ACM angle, MZ distance, Sharp angle, CE angle, Femoral Head Coverage Ratio, Cranial, and medial joint space (MJS). *p < 0.05; **p < 0.01 indicated a statistically significant difference. It was found that Acetabular Index, ACM angle, MZ distance, Sharp angle, Cranial, and MJSs decreased with age; Acetabular Depth value and CE angle increased with age; the CE angle differed between the sides (right-left) in the young teens period and in boys; and the cranial joint space (CJS) differed between the sides in girls. In addition, girls had higher values than boys in terms of Acetabular Index, ACM angle, Sharp angle, MZ distance, and Femoral Head Coverage Ratio; CE angle and MJS were higher in girls; and Acetabular Depth Value and CJS did not differ significantly between sexes. Obtaining the normal values will guide in the diagnosis and treatment of many clinical conditions including DDH and Legg-Calve-Perthes disease. It can also be used to compare the hips between healthy children and those diagnosed with Cerebral Palsy.


Assuntos
Articulação do Quadril , Doença de Legg-Calve-Perthes , Masculino , Feminino , Adolescente , Humanos , Criança , Pré-Escolar , Articulação do Quadril/diagnóstico por imagem , Acetábulo , Cabeça do Fêmur/diagnóstico por imagem , Osteotomia , Estudos Retrospectivos
4.
Biomimetics (Basel) ; 8(1)2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36810401

RESUMO

One of the most important challenges for heterogeneous wireless sensor networks (HWSNs) is adequate network coverage and connectivity. Aiming at this problem, this paper proposes an improved wild horse optimizer algorithm (IWHO). Firstly, the population's variety is increased by using the SPM chaotic mapping at initialization; secondly, the WHO and Golden Sine Algorithm (Golden-SA) are hybridized to improve the WHO's accuracy and arrive at faster convergence; Thirdly, the IWHO can escape from a local optimum and broaden the search space by using opposition-based learning and the Cauchy variation strategy. The results indicate that the IWHO has the best capacity for optimization by contrasting the simulation tests with seven algorithms on 23 test functions. Finally, three sets of coverage optimization experiments in different simulated environments are designed to test the effectiveness of this algorithm. The validation results demonstrate that the IWHO can achieve better and more effective sensor connectivity and coverage ratio compared to that of several algorithms. After optimization, the HWSN's coverage and connectivity ratio attained 98.51% and 20.04%, and after adding obstacles, 97.79% and 17.44%, respectively.

5.
BMC Pediatr ; 22(1): 228, 2022 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-35473514

RESUMO

BACKGROUND: This study investigated the association between early Graf classification and femoral head coverage (FHC) with the acetabular index (AI) at the age of 6 months. METHODS: A prospective observational study was conducted between 2017-2018. Patients requiring Pavlik harness treatment and patients with syndromic dislocation or neurogenic dislocation were excluded. In total, 169 newborns with the first ultrasound performed at the mean age of 12.3 (0-15) days, the second ultrasound performed at the mean age of 3.2 (2.5-4.1) months, and the AI measured at the age of 6.6 (4.3-7.1) months were enrolled. The correlation between the AI and first and second alpha angles and FHC measurements, and the correlation of dysplasia in early ultrasound with dysplasia in the AI were analyzed. RESULTS: At the first ultrasound, only the FHC (P = .02) demonstrated a significant negative correlation with the AI. At the second ultrasound, both the alpha angle (P < .01) and FHC (P < .01) demonstrated a significant negative correlation with the AI. With the AI as a reference, the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were found to be 77%, 7%, 5%, and 81%, respectively, for the first Graf; 91%, 37%, 9%, and 98%, respectively, for the first FHC measurement; 82%, 90%, 35%, and 99%, respectively, for the second Graf; and 95%, 97%, 68% and 99%, respectively, for the second FHC measurement. CONCLUSIONS: FHC and alpha angle exhibited significant negative correlations with the AI at six months, both ultrasound parameters may have the potential to predict AI in DDH screening. Compared to the ultrasound measurements taken at 2 weeks, Graf and FHC at 3 months demonstrated superior sensitivity, specificity, PPV, and NPV to detect abnormal AI. The best timing to perform ultrasound examination may need further research.


Assuntos
Luxação Congênita de Quadril , Criança , Pré-Escolar , Luxação Congênita de Quadril/diagnóstico por imagem , Luxação Congênita de Quadril/terapia , Humanos , Lactente , Recém-Nascido , Valor Preditivo dos Testes , Estudos Prospectivos , Ultrassonografia
6.
MethodsX ; 8: 101260, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34434782

RESUMO

Banks must maintain, calculate, and monitor liquidity using the Liquidity Coverage Ratio (LCR) indicator. In Indonesia, they reported daily, monthly, or quarterly online through a paper template prepared by the Financial Services Authority (OJK). This reporting must accurate and on time or be subject to penalties. For banks that are still processing LCR semi-automatically, this reporting system is an obstacle that they continue to face and resolve. This article discusses the automation process method developed using the concept of Extract Transform Load (ETL), with a waterfall software development model, so that daily reports are generated automatically. This article proposed a methodology to anticipate problems in integrating banking with regulators by applying one of the Basel III frameworks, primarily based on Indonesia's case studies. The finding of the research is a method for the LCR report process through ETL. The proposed ETL method in this research had proven used success in processing LCR in the banking industry. This method is a solution and recommendation for banks in making reports based on Basel III to complete LCR reporting through the ETL method.•o Maintain, calculate, and monitor liquidity using the Liquidity Coverage Ratio (LCR) indicator in Banking .•o Automation process method developed using the concept of Extract Transform Load (ETL).•o Recommendation for Banks to complete LCR reporting through the ETL method).

7.
ISA Trans ; 96: 299-308, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31326078

RESUMO

The selective catalytic reduction (SCR) is a resultful technical approach to diminish the NOx emission in the diesel-engine exhaust. And closed-loop control is of vital importance for SCR system to realize high NOx reduction and low ammonia tailpipe leakage. The input ammonia and the ammonia coverage ratio are two crucial parameters, but the cost of a sensor measuring the former is high, and the latter cannot be obtained by the sensor directly. Thus an observer based on square-root unscented Kalman filter is designed to estimate the two parameters. Meanwhile, a three-state model is established to mathematically describe the SCR system. The simulation results show that the observer can make an outstanding estimation on the state variables, and it shows strong robustness to the external interference.

8.
Acta Orthop Traumatol Turc ; 53(5): 346-350, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31400967

RESUMO

OBJECTIVE: The aim of this study was to investigate whether being the parents of children with developmental hip dysplasia (DDH) is a risk factor for asymptomatic dysplasia. METHODS: Asymptomatic parents of children who were diagnosed with DDH were assessed for presence of dysplasia by examining their anteroposterior pelvis radiographs at the neutral position. Eighty-six hips of 43 participants were included in the study group and 98 hips of 49 participants were included in the control group. Presence of hip dysplasia over the anteroposterior pelvis radiographs was analyzed for Wiberg's angle, acetabular index of the weight-bearing zone (the Tönnis angle), acetabular depth/width index, femoral head coverage ratio (FHCR) and femoral neck/shaft angle. RESULTS: The mean acetabular depth/width ratio was 44.3% in the study group and 53.5% in the control group. And, the mean FHCR was 80% in the study group and 82% in the control group. There was a statistically significant difference between the two groups in terms of mean acetabular depth/width ratio (p < 0.05) and FHCR (p < 0.05). In addition, 21 participants in the study group and 2 in the control group had a pathological acetabular depth/width ratio. And, the number of participants with a pathological FHCR was 22 in the study group and 13 in the control group. A statistically significant difference was found between the two groups regarding the number of pathological measurements of acetabular depth/width ratio (p < 0.05) and FHCR (p < 0.05). CONCLUSION: Having a parent with DDH is a definitive risk factor for the development of hip dysplasia in childhood. In addition, being a parent of a child with DDH is a risk factor for asymptomatic dysplasia. These parents should be screened by roentgenogram. LEVEL OF EVIDENCE: Level III, Diagnostic Study.


Assuntos
Acetábulo , Doenças Assintomáticas/epidemiologia , Luxação Congênita de Quadril , Articulação do Quadril , Pais , Acetábulo/diagnóstico por imagem , Acetábulo/patologia , Adulto , Criança , Correlação de Dados , Feminino , Luxação Congênita de Quadril/diagnóstico , Luxação Congênita de Quadril/epidemiologia , Articulação do Quadril/anormalidades , Articulação do Quadril/diagnóstico por imagem , Humanos , Masculino , Radiografia/métodos , Estudos Retrospectivos , Medição de Risco/métodos , Medição de Risco/estatística & dados numéricos , Fatores de Risco
9.
Artigo em Inglês | MEDLINE | ID: mdl-30634535

RESUMO

Growing and densifying cities set a challenge for preserving and enhancing green spaces to cool urban spaces. Green roofs, involving the planting of vegetation on rooftops, are regarded as an alternative approach to enhancing urban greenery and urban cooling. For better cooling performances, it is essential to reasonably configure green roofs, especially in real and complex neighborhoods. Therefore, the aim of this paper is to investigate the impact of morphological characteristics of green roofs on pedestrian cooling in real and complex neighborhoods. In specific, based on an ENVI-met model, we studied the effect of greening layout, coverage ratio, vegetation height, and building height on pedestrian air temperature reduction in the tropical city of Hangzhou, China. Results indicate green roofs could generate moderate effects on pedestrian air temperature reduction (around 0.10⁻0.30 °C), while achieving a cooling performance of 0.82 °C. Green roofs in upwind zones were able to generate the most favorable cooling performance, while green roofs in downwind zones made slight differences to pedestrian thermal environments. Green roofs with a low coverage ratio were not useful for lowering pedestrian temperature, and a greening coverage ratio of 25⁻75% in upwind zones was cost-effective in real neighborhoods. Locations that were horizontally close to green roofs enjoyed better cooling performances. Increasing vegetation height could strengthen cooling effects of green roofs, while an increase in building height weakened the cooling performance. Nevertheless, higher building height could enhance pedestrian cooling performances because of building shading effects. In addition, because of wind effects and building shading, building height limits for the cooling performance of green roofs could be higher than 60 m.


Assuntos
Arquitetura de Instituições de Saúde , Pedestres , Plantas , Temperatura , China , Cidades , Clima , Conservação dos Recursos Naturais
10.
Genes (Basel) ; 9(12)2018 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-30563180

RESUMO

B chromosomes (Bs) were discovered a century ago, and since then, most studies have focused on describing their distribution and abundance using traditional cytogenetics. Only recently have attempts been made to understand their structure and evolution at the level of DNA sequence. Many questions regarding the origin, structure, function, and evolution of B chromosomes remain unanswered. Here, we identify B chromosome sequences from several species of cichlid fish from Lake Malawi by examining the ratios of DNA sequence coverage in individuals with or without B chromosomes. We examined the efficiency of this method, and compared results using both Illumina and PacBio sequence data. The B chromosome sequences detected in 13 individuals from 7 species were compared to assess the rates of sequence replacement. B-specific sequence common to at least 12 of the 13 datasets were identified as the "Core" B chromosome. The location of B sequence homologs throughout the genome provides further support for theories of B chromosome evolution. Finally, we identified genes and gene fragments located on the B chromosome, some of which may regulate the segregation and maintenance of the B chromosome.

11.
Genome Biol Evol ; 9(10): 2844-2861, 2017 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-29036290

RESUMO

The root-knot nematodes (genus Meloidogyne) are important plant parasites causing substantial agricultural losses. The Meloidogyne incognita group (MIG) of species, most of which are obligatory apomicts (mitotic parthenogens), are extremely polyphagous and important problems for global agriculture. While understanding the genomic basis for their variable success on different crops could benefit future agriculture, analyses of their genomes are challenging due to complex evolutionary histories that may incorporate hybridization, ploidy changes, and chromosomal fragmentation. Here, we sequence 19 genomes, representing five species of key root-knot nematodes collected from different geographic origins. We show that a hybrid origin that predated speciation within the MIG has resulted in each species possessing two divergent genomic copies. Additionally, the apomictic MIG species are hypotriploids, with a proportion of one genome present in a second copy. The hypotriploid proportion varies among species. The evolutionary history of the MIG genomes is revealed to be very dynamic, with noncrossover recombination both homogenizing the genomic copies, and acting as a mechanism for generating divergence between species. Interestingly, the automictic MIG species M. floridensis differs from the apomict species in that it has become homozygous throughout much of its genome.


Assuntos
Evolução Molecular , Genoma Helmíntico/genética , Genômica , Hibridização Genética , Partenogênese/genética , Ploidias , Tylenchoidea/genética , Animais , Especiação Genética , Variação Genética , Genoma Mitocondrial/genética , Filogenia , Doenças das Plantas/parasitologia , Raízes de Plantas/parasitologia , Análise de Sequência de DNA
12.
BMC Genomics ; 18(1): 350, 2017 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-28472946

RESUMO

BACKGROUND: Most tailed bacteriophages (phages) feature linear dsDNA genomes. Characterizing novel phages requires an understanding of complete genome sequences, including the definition of genome physical ends. RESULT: We sequenced 48 Bacillus cereus phage isolates and analyzed Next-generation sequencing (NGS) data to resolve the genome configuration of these novel phages. Most assembled contigs featured reads that mapped to both contig ends and formed circularized contigs. Independent assemblies of 31 nearly identical I48-like Bacillus phage isolates allowed us to observe that the assembly programs tended to produce random cleavage on circularized contigs. However, currently available assemblers were not capable of reporting the underlying phage genome configuration from sequence data. To identify the genome configuration of sequenced phage in silico, a terminus prediction method was developed by means of 'neighboring coverage ratios' and 'read edge frequencies' from read alignment files. Termini were confirmed by primer walking and supported by phylogenetic inference of large DNA terminase protein sequences. CONCLUSIONS: The Terminus package using phage NGS data along with the contig circularity could efficiently identify the proximal positions of phage genome terminus. Complete phage genome sequences allow a proposed characterization of the potential packaging mechanisms and more precise genome annotation.


Assuntos
Fagos Bacilares/genética , Bacillus cereus/virologia , Genoma Viral , Sequência de Bases , Mapeamento Cromossômico , Mapeamento de Sequências Contíguas , DNA Viral/genética , Sequenciamento de Nucleotídeos em Larga Escala , Filogenia , Análise de Sequência de DNA , Proteínas Virais/genética
13.
Sensors (Basel) ; 17(4)2017 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-28387746

RESUMO

Understanding interactions of genotype, environment, and management under field conditions is vital for selecting new cultivars and farming systems. Image analysis is considered a robust technique in high-throughput phenotyping with non-destructive sampling. However, analysis of digital field-derived images remains challenging because of the variety of light intensities, growth environments, and developmental stages. The plant canopy coverage (PCC) ratio is an important index of crop growth and development. Here, we present a tool, EasyPCC, for effective and accurate evaluation of the ground coverage ratio from a large number of images under variable field conditions. The core algorithm of EasyPCC is based on a pixel-based segmentation method using a decision-tree-based segmentation model (DTSM). EasyPCC was developed under the MATLAB® and R languages; thus, it could be implemented in high-performance computing to handle large numbers of images following just a single model training process. This study used an experimental set of images from a paddy field to demonstrate EasyPCC, and to show the accuracy improvement possible by adjusting key points (e.g., outlier deletion and model retraining). The accuracy (R² = 0.99) of the calculated coverage ratio was validated against a corresponding benchmark dataset. The EasyPCC source code is released under GPL license with benchmark datasets of several different crop types for algorithm development and for evaluating ground coverage ratios.


Assuntos
Benchmarking , Agricultura , Algoritmos
14.
Sensors (Basel) ; 16(11)2016 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-27827908

RESUMO

The stricter legislation within the European Union for the regulation of herbicides that are prone to leaching causes a greater economic burden on the agricultural industry through taxation. Owing to the increased economic burden, research in reducing herbicide usage has been prompted. High-resolution images from digital cameras support the studying of plant characteristics. These images can also be utilized to analyze shape and texture characteristics for weed identification. Instead of detecting weed patches, weed density can be estimated at a sub-patch level, through which even the identification of a single plant is possible. The aim of this study is to adapt the monocot and dicot coverage ratio vision (MoDiCoVi) algorithm to estimate dicotyledon leaf cover, perform grid spraying in real time, and present initial results in terms of potential herbicide savings in maize. The authors designed and executed an automated, large-scale field trial supported by the Armadillo autonomous tool carrier robot. The field trial consisted of 299 maize plots. Half of the plots (parcels) were planned with additional seeded weeds; the other half were planned with naturally occurring weeds. The in-situ evaluation showed that, compared to conventional broadcast spraying, the proposed method can reduce herbicide usage by 65% without measurable loss in biological effect.


Assuntos
Herbicidas/análise , Agricultura , Algoritmos , Produtos Agrícolas/química , Folhas de Planta/química , Zea mays/química
15.
Nanomicro Lett ; 7(1): 42-50, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-30464955

RESUMO

Graphene is mainly implemented by these methods: exfoliating, unzipping of carbon nanotubes, chemical vapour deposition, epitaxial growth and the reduction of graphene oxide. The latter option has the advantage of low cost and precision. However, reduced graphene oxide (rGO) contains hydrogen and/or oxygen atoms hence the structure and properties of the rGO and intrinsic graphene are different. Considering the advantages of the implementation and utilization of rGO, voltage-dependent electronic transport properties of several rGO samples with various coverage ratios are investigated in this work. Ab initio simulations based on density functional theory combined with non-equilibrium Green's function formalism are used to obtain the current-voltage characteristics and the voltage-dependent transmission spectra of rGO samples. It is shown that the transport properties of rGO are strongly dependent on the coverage ratio. Obtained results indicate that some of the rGO samples have negative differential resistance characteristics while normally insulating rGO can behave as conducting beyond a certain threshold voltage. The reasons of the peculiar electronic transport behaviour of rGO samples are further investigated, taking the transmission eigenstates and their localization degree into consideration. The findings of this study are expected to be helpful for engineering the characteristics of rGO structures.

16.
Biosci. j. (Online) ; 29(2): 308-318, mar./apr. 2013. tab, graf
Artigo em Português | LILACS | ID: biblio-914392

RESUMO

As plantas de cobertura podem melhorar as condições físicas, químicas e biológicas do solo, com consequente aumento na produtividade da cultura em sucessão. Objetivou-se com este trabalho avaliar a produtividade de matéria fresca e seca de plantas de cobertura, em dois espaçamentos, a extração de nutrientes, e o potencial destas espécies vegetais, visando o controle da erosão e o fornecimento de nutrientes à cultura em sucessão. O estudo foi conduzido, em duas etapas, no Departamento de Agricultura da UFLA. A primeira etapa, consistiu da semeadura das plantas de cobertura, usando delineamento experimental de blocos casualizados, em esquema fatorial (4 x 2), com três blocos. O primeiro fator constituído de Canavalia ensiformes (L.) DC. (feijão-de-porco), Stizolobium deeringianum Bort (mucuna-rajada), Stizolobium aterrimum Piper et Tracy (mucuna-preta), e Sorghum bicolor (L.) Moench (sorgo), e o segundo pelos espaçamentos de 25 e 50 cm. As características avaliadas nesta etapa foram: índice de cobertura, matéria fresca e seca e acúmulo de nutrientes. A espécie Canavalia ensiformes apresentou a maior cobertura do solo em menor tempo no espaçamento de 25 cm e as leguminosas proporcionaram maior produção de fitomassa e acúmulo de nutrientes no espaçamento de 50 cm. A segunda etapa foi implantada sob a cobertura vegetal remanescente do cultivo anterior obtida na primeira etapa, com a inclusão do esquema fatorial com tratamento adicional, que foi a parcela com vegetação espontânea. Nesta etapa foram avaliadas: produtividade de espigas empalhadas e despalhadas, produtividade de espigas comerciais despalhadas, porcentagem de espigas comerciais, altura de planta da cultura do milho verde. O milho verde, quando cultivado nas parcelas com palhadas de leguminosas apresentou maior produtividade comparado com a palhada de sorgo.


Cover crops can improve the physical, chemical and biological soil, with consequent increase in productivity of the crop in succession. The objective of this work to estimate the productivity of fresh and dry plant cover, in two spaces, nutrient uptake, and the potential of these plant species in order to control erosion and providing nutrients to the crop in succession. The study was conducted in two phases, in the Department of Agriculture UFLA. The first phase consisted of the planting of cover plants, using the experimental design of randomized blocks in factorial scheme (4 x 2), with 3 replications. The first factor consists of Canavalia ensiformes (L.) DC. (Pig bean), Stizolobium deeringianum Bort (Mucuna-burst), Stizolobium aterrimum Piper et Tracy (mucuna-blast) and Sorghum bicolor (L.) Moench (sorghum), and the second by spacings of 25 and 50 cm. The characteristics evaluated in this phase were: coverage ratio, fresh and dry matter and nutrient accumulation. The species Canavalia ensiformes showed the highest soil cover in less time with spacing of 25 cm and legumes showed greater production of biomass and nutrient accumulation in the spacing of 50 cm. The second phase was implemented under the straw of the culture remaining from the previous first stage, with the inclusion of the factorial with additional treatment, which was the spontaneous vegetation. In this step were evaluated: yield of ears with husk and without husk, husked productivity of commercial ears, percentage of commercial ears, plant height of corn green. After the management of plant cover was sown green corn. The straw of legumes promoted greater productivity of green corn compared with the straw of sorghum.


Assuntos
Alimentos , Zea mays , Canavalia , Conservação de Terras
17.
Biosci. j. (Online) ; 27(5): 775-785, sept./oct. 2011.
Artigo em Português | LILACS | ID: biblio-911868

RESUMO

As plantas de cobertura desempenham um conjunto de ações integradas que proporcionam benefícios aos sistemas agrícolas, com destaque para a redução da erosão hídrica que é a principal forma de degradação dos solos brasileiros. Assim, objetivou-se com este trabalho quantificar as perdas de solo, água e o potencial de arraste de sedimentos decorrentes da erosão hídrica, sob chuva natural. Neste experimento foram utilizadas quatro espécies de plantas de cobertura em dois sistemas: consórcio milheto (Pennisetum glaucum (L.) R.Brown) com crotalária (Crotalaria spectabilis Roth) e consórcio de milheto com feijão-guandu (Cajanus cajan (L.) Huth), além do cultivo solteiro do milheto, feijão-guandu, feijão-de-porco (Canavalia ensiformis (L.) DC) e crotalária. Para a quantificação das perdas de solo, água e potencial de arraste de sedimentos do solo utilizaram-se parcelas de 4 x 12 m. Observou-se que os maiores índices de cobertura foram obtidos pelas espécies feijão-de-porco (77,63%), feijão-guandu (64,55%) e pelo consórcio milheto + feijão-guandu (64,11%). As menores perdas de solo foram obtidas pelo cultivo do feijão-guandu (1,27 Mg ha-1), do milheto (1,47 Mg ha-1) e do feijão-de-porco (1,77 Mg ha-1), e as menores perdas de água foram obtidas pelo cultivo do feijão-guandu (37,90 mm), do consórcio milheto + crotalária (40,04 mm) e pelo feijão-de-porco (41,83 mm). Não é possível inferir sobre uma relação entre os índices fitotécnicos e a proteção do solo contra a erosão hídrica.


Cover crops play a set of integrated actions that provide benefits to agricultural systems, with emphasis on reducing water erosion that is the main form of land degradation in Brazil. Thus the aim of this work was to quantify the losses of soil, water and the potential for entrainment of sediment resulting from water erosion under natural rainfall. In this experiment we used four species of cover crops in two systems: intercropping sunn hemp with millet and intercropping millet with pigeon pea, and the cropping to millet, pigeon pea, jack bean and sunn hemp. To quantify the losses of soil, water and the potential for entrainment of soil sediment were used plots of 4 x 12 m. It was observed that the highest rates of coverage were obtained by species jack bean (77.63%), pigeon pea (64.55%) and the consortium millet + pigeon pea (64.11%). The lowest soil loss was obtained by cultivation of pigeon pea (1.27 Mg ha-1), millet (1.47 Mg ha-1) and jack bean (1.77 Mg ha-1), and lowest water loss was obtained by cultivation of pigeon pea (37.90 mm), in the consortium millet + sunn hemp (40.04 mm) and jack bean (41.83 mm). It is not possible to infer a relationship between the rates phytotechnical and protection against soil erosion.


Assuntos
Cajanus , Canavalia , Crotalaria , Conservação de Terras , Pennisetum , Erosão do Solo
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