Recursos de colección

UTL Repository Universidade Técnica de Lisboa (32.124 recursos)

O Repositório Institucional da Universidade Técnica de Lisboa desenvolvido no âmbito do projecto RCAAP. Este repositório destina-se a recolher, preservar e disponibilizar o acesso às publicações científicas e didácticas de seis: Escolas da UTL: Faculdade de Medicina Veterinária, Instituto Superior de Agronomia, Instituto Superior de Economia e Gestão, Instituto Superior de Ciências Sociais e Políticas , Faculdade de Motricidade Humana, Faculdade de Arquitectura. O Instituto Superior Técnico, igualmente Escola Da UTL, tem repositório independente.

LEAF - Centro de Investigação em Agronomia, Alimentos, Ambiente e Paisagem

Mostrando recursos 1 - 20 de 34

  1. Water use by a groundwater dependent maize in a semi-arid region of Inner Mongolia: evapotranspiration partitioning and capillary rise

    Wu, Yao; Liu, Tingxi; Paredes, Paula; Duan, Limin; Pereira, L.S.
    tThis study aimed at assessing the soil water balance, groundwater contribution, crop transpiration andsoil evaporation of a rainfed maize crop in Horqin sandy area, north-eastern Inner Mongolia, China.Two years of field data from the Agula site were used, 2008 with relatively high rainfall (363 mm) andhigh water table, and 2009 with low rainfall (125 mm) and lower water table. The SIMDualKc waterbalance model was calibrated with observed soil water content data of 2008 and validated with dataof 2009. The model uses the dual crop coefficient approach for evapotranspiration (ET) partitioning,and parametric functions for computing capillary rise. The respective modelling results...

  2. Texture, microstructure and consumer preference of mango bars jellified with gellan gum

    Danalache, Florina; Beirão-da-Costa, Sara; Mata, Paulina; Alves, Vitor D.; Martins, Margarida Moldão
    Studies for the development of a novel convenient fruit product based on mango puree and gellan gum were carried out. Two gellan types (low acyl-L and high acyl-H) used in specific L/H ratios (75/25, 50/50, 25/75) for an overall concentration of 1 g of gellan/100 g of puree were tested, in order to design different mango bars. The influence of the L/H gellan ratio on their texture properties (TPA and SR tests), microstructure (Cryo-Scanning Electron Microscopy) and texture sensory acceptance (Preference- Ranking test) was studied. The results obtained enabled to separate the bars in two groups: the ones showing greater hardness and brittleness (only L gellan,...

  3. Field assessment of basin irrigation performance and water saving in Hetao, Yellow River basin: issues to support irrigation systems modernisation

    Miao, Qingfeng; Shi, Haibin; Gonçalves, José M.; Pereira, L.S.
    Research Paper

  4. Assessing and modelling water use and the partition of evapotranspiration of irrigated hop (Humulus lupulus) and relations of transpiration with hops yield and alpha-acids

    Fandiño, M.; Olmedo, J.L.; Martinez, E.M.; Valladares, J.; Paredes, P.; Rey, B.J.; Mota, M.; Cancela, J.J.; Pereira, L.S.
    This study was conducted during three seasons (2012–2014) in an experimental hop yard at Mabegondo,Galicia, NW Spain. The research aimed at calibrating and validating the soil water balance model SIMD-ualKc for Humulus lupulus L. cv. ‘Nugget’. The model computes the soil water balance using the dualKcapproach, thus partitioning crop evapotranspiration (ETc) into crop transpiration, ground covertranspiration and soil evaporation. Calibration and validation were performed using TDR soil watercontent measurements, which produced small root mean square errors (RMSE) ranging from 0.012 to0.015 cm3cm−3. The initial, mid-season and end-season basal crop coefficients (Kcb) that allow com-puting hop transpiration were respectively 0.16, 0.97...

  5. Effects of the European Union agricultural and environmental policies in the sustainable of most common mediterranean soils

    Nunes, José Manuel Rato; Bonito, António; Loures, Luís; Gama, José; López-Piñero, Antonio; Peña, David; Albarrán, Ángel
    Agro-environmental measures promoted by the European Union focus mainly on environmental protection by maintaining sustainable levels of productivity that are adequate to the agro-ecological conditions of each region on different Member States. Among these European Union promoted measures the one known as “Extensive Forage Systems” is particularly relevant for the Mediterranean Region. In order to analyze the impact of this measure and to verify if the high expenditure of communitarian funds, with its implementation in Mediterranean soils, is aligned with the predicted benefits, a seven-year study in a southern Portugal region was conducted. In this regard, several soil chemical parameters such as organic matter, pH, electrical conductivity, “available”...

  6. The N-P-K soil nutrient balance of portuguese cropland in the 1950s: the transition from organic to chemical fertilization

    Carmo, Miguel; Garcia-Ruiz, Roberto; Ferreira, Maria Isabel; Domingos, Tiago
    Agricultural nutrient balances have been receiving increasing attention in both historical and nutrient management research. The main objectives of this study were to further develop balance methodologies and to carry out a comprehensive assessment of the functioning and nutrient cycling of 1950s agroecosystems in Portugal. Additionally, the main implications for the history of agriculture in Portugal were discussed from the standpoint of soil fertility. We used a mass balance approach that comprises virtually all nitrogen (N), phosphorus (P) and potassium (K) inputs and outputs from cropland topsoil for average conditions in the period 1951–56. We found a consistent deficit in N, both for nationwide (−2.1 kg.ha−1.yr−1) and...

  7. Bridging the gap to non-toxic fungal control: lupinus-derived blad-containing ologomer as a novel candidate to combat human pathgenic fungi

    Pinheiro, Ana M.; Carreira, Alexandra; Prescott, Thomas A.K.; Ferreira, Ricardo Boavida; Monteiro, Sara A.
    Original Research

  8. Como promover os serviços de ecossistema na agricultura usando a biodiversidade: o caso de estudo da perceção da fileira da vinha

    Branquinho, Cristina; Proença, Vania; Grilo, Filipa; Sardinha, Idalina Dias; Faria, Margarida Lima; Franco, José Carlos; Romeiras, Maria Manuel; Monteiro, Filipa; Goulão, Luís F.; Santos-Reis, Margarida

  9. Agricultura e biodiversidade: uma diversidade de temas

    Santos, José Manuel Lima

  10. Water use and yield of soybean under various irrigation regimes and severe water stress. Application of AquaCrop and SIMDualKc models

    Giménez, Luis; Paredes, Paula; Pereira, L.S.
    Data relative to two soybean seasons, several irrigation scheduling treatments, including moderate and severe deficit irrigation, and rain-fed cropping were used to parameterize and assess the performance of models AquaCrop and SIMDualKc, the latter combined with the Stewart’s yield model. SIMDualKc applies the FAO56 dual crop coefficient approach for computing and partitioning evapotranspiration (ET) into actual crop transpiration (Tc act) and soil evaporation (Es), while AquaCrop uses an approach that depends on the canopy cover curve. The calibration-validations of models were performed by comparing observed and predicted soil water content (SWC) and grain yield. SIMDualKc showed good accuracy for SWC estimations, with normalized root mean square error (NRMSE)...

  11. Study of autumn-winter weeds in Portugal and its ecological preferences

    Ramôa, S.; Oliveira e Silva, P.; Vasconcelos, T.; Fortes, P.; Portugal, J.
    The conclusion of the dam project located in Alqueva, in Southern Portugal, has resulted in a significant increase of new irrigated areas, since 2006. This has meant that, in recent years, there have been progressive flora changes in farming systems traditionally implemented in the Alentejo region. The present work has analyzed the weed flora in an early stage of these changes, and the impact of environmental factors on the distribution of natural vegetation under Mediterranean climate conditions in the influence area of Alqueva. In 2007, 105 floristic surveys were carried out in autumn-winter crop plots or other soil use, and 264 species were identified. Families with higher...

  12. Estimation of actual crop coefficients using remotely sensed vegetation indices and soil water balance modelled data

    Pôças, Isabel; Paço, Teresa Afonso; Paredes, Paula; Cunha, Mário; Pereira, L.S.
    A new procedure is proposed for estimating actual basal crop coefficients from vegetation indices (Kcb VI) considering a density coefficient (Kd) and a crop coefficient for bare soil. Kd is computed using the fraction of ground cover by vegetation (fc VI), which is also estimated from vegetation indices derived from remote sensing. A combined approach for estimating actual crop coefficients from vegetation indices (Kc VI) is also proposed by integrating the Kcb VI with the soil evaporation coefficient (Ke) derived from the soil water balance model SIMDualKc. Results for maize, barley and an olive orchard have shown that the approaches for estimating both fc VI and Kcb...

  13. Effect of ethanol, sulfur dioxide and glucose on the growth of wine spoilage teasts using response surface methodology

    Chandra, Mahesh; Oro, Inês; Ferreira-Dias, Suzana; Malfeito-Ferreira, Manuel
    Research Article

  14. Fisiologia e metabolismo foliar em duas variedades de videira sujeitas a um ciclo de défice hídrico e reidratação

    Cerqueira, Reginaldo Conceição; Costa, Joaquim Miguel; Chaves, Maria Manuela; Rodrigues, João Domingos
    Este trabalho teve como objetivo comparar duas variedades de videira cultivadas em Portugal, Syrah e Touriga Nacional, em termos de suas respostas fisiológicas e bioquímicas a um ciclo de estresse hídrico severo seguido de reidratação. Os tratamentos consistiram em videiras continuamente regadas (FI) e videiras não regadas durante 21 dias e reidratadas após o potencial hídrico foliar de base (Ψpd) atingir cerca de -1,1MPa (NI). As observações ocorreram em quatro momentos: i) imediatamente antes de suprimir a rega (dia 0), ii) no momento de máximo de estresse (dia 21), iii) dois dias após reidratação (dia 23) e iv) seis dias após reidratação (dia 27). Mediu-se...

  15. Exopolysaccharides enriched in rare suggars: bacterial sources, production and applications

    Roca, Christophe; Alves, Vitor D.; Freitas, Filomena; Reis, Maria A.M.
    Mini Review

  16. Environmental and microbial factors influencing methane and nitrous oxide fluxes in Mediterranean cork oak woodlands: trees make a difference

    Shvaleva, Alla; Siljanen, Henri M.; Correia, Alexandra; Silva, Filipe Costa e; Lamprecht, Richard E.; Lobo-do-Vale, Raquel; Bicho, Catarina; Fangueiro, David; Anderson, Margaret; Pereira, João Santos; Chaves, Maria Manuela; Cruz, Cristina; Martikainen, Pertti J.
    Original Research

  17. Characterization of the serine acetyltransferase gene family of Vitis vinifera uncovers differences in regulation of OAS synthesis in woody plants

    Tavares, Sílvia; Wirtz, Markus; Beier, Marcel P.; Bogs, Jochen; Hell, Rudiger; Amâncio, Sara
    Original Research Article

  18. The design and evaluation of travelling gun irrigation systems: enrolador software

    Rolim, Joâo; Teixeira, José Luís
    Technical Paper

  19. Genetic diversity assessment of portuguese cultivated Vicia faba L. through IRAP markers

    Tomás, Diana; Dias, Ana Luísa; Silva, Manuela; Oliveira, Hugo R.; Suso, Maria José; Viegas, Wanda; Veloso, Maria Manuela
    Faba bean have been grown in Portugal for a long time and locally adapted populations are still maintained on farm. The genetic diversity of four Portuguese faba bean populations that are still cultivated in some regions of the country was evaluated using the Inter Retrotransposons Amplified Polymorphism (IRAP) technique. It was shown that molecular markers based on retrotransposons previously identified in other species can be efficiently used in the genetic variability assessment of Vicia faba. The IRAP experiment targeting Athila yielded the most informative banding patterns. Cluster analysis using the neighbor-joining algorithm generated a dendrogram that clearly shows the distribution pattern of V. faba samples. The four...

  20. Nitric oxide and nitrous oxide emissions from cattle-slurry and mineral fertiliser treated with nitrification inhibitor to an agricultural soil: a laboratory approach

    Pereira, José; Coutinho, João; Fangueiro, David; Trindade, Henrique
    Research Article

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