A Bayesian approach to estimate sensible and latent heat over vegetated land surface

Sensible and latent heat fluxes are often calculated from bulk transfer equations combined with the energy balance. For spatial estimates of these fluxes, a combination of remotely sensed and standard meteorological data from weather stations is used. The success of this approach depends on the accuracy of the input data and on the accuracy of two variables in particular: aerodynamic and surface conductance. This paper presents a Bayesian approach to improve estimates of sensible and latent heat fluxes by using a priori estimates of aerodynamic and surface conductance alongside remote measurements of surface temperature. The method is validated for time series of half-hourly measurements in a fully grown maize field, a vineyard and a forest. It is shown that the Bayesian approach yields more accurate estimates of sensible and latent heat flux than traditional methods.

A novel method for assessing risks to pollinators from plant protection products using honeybees as a model species

Pollination is one of the most important ecosystem services in agroecosystems and supports food production. Pollinators are potentially at risk being exposed to pesticides and the main route of exposure is direct contact, in some cases ingestion, of contaminated materials such as pollen, nectar, flowers and foliage. To date there are no suitable methods for predicting pesticide exposure for pollinators, therefore official procedures to assess pesticide risk are based on a Hazard Quotient. Here we develop a procedure to assess exposure and risk for pollinators based on the foraging behaviour of honeybees (Apis mellifera) and using this species as indicator representative of pollinating insects. The method was applied in 13 European field sites with different climatic, landscape and land use characteristics. The level of risk during the crop growing season was evaluated as a function of the active ingredients used and application regime. Risk levels were primarily determined by the agronomic practices employed (i.e. crop type, pest control method, pesticide use), and there was a clear temporal partitioning of risks through time. Generally the risk was higher in sites cultivated with permanent crops, such as vineyard and olive, than in annual crops, such as cereals and oil seed rape. The greatest level of risk is generally found at the beginning of the growing season for annual crops and later in June–July for permanent crops.

“Les petits renards qui détruisent la Vigne du Seigneur Sabaoth”. Innocent III et le Cantique des cantiques

This article examines medieval interpretations of the Song of Songs and their appearance in the correspondence of one of the greatest popes of the High Middle Ages: Innocent III (1198-1216). Innocent III’s depiction of heretics in the south of France as ‘the little foxes which destroy the vineyard of the Lord of Hosts’ was not unprecedented: decades earlier Saint Bernard of Clairvaux had also likened the ‘little foxes’ to heretics in his sermons. Bernard’s renown both as mystical theologian and tireless political advocate of the papacy meant that Innocent is likely to have drawn on such sermons for inspiration when composing his correspondence to the Christian faithful. Innocent’s references to the Song of Songs also provide conclusive evidence that a significant number of his letters have a highly personal flavour and that we really can discern a pope’s own ‘voice’ through his correspondence.

Recycled effluent irrigation in vineyards : an Australian case study. I. issues and monitoring

The viticultural industry is becoming an increasingly significant part of the Australian agricultural sector, with gross earnings of over $4 billion in 2002. Expansion of the industry in the last decade has been rapid, however its heavy reliance on irrigation has resulted in further expansion in many wine growing regions being limited by the availability of water. This problem is not confined to the viticultural industry, with ever increasing pressures on water resources worldwide. As demands for water continue to rise, new strategies to meet demands must be adopted. One of the strategies being increasingly employed is the recycling of waste waters for a number of applications such as irrigation and industrial uses. The use of recycled water for vineyard irrigation provides a number of benefits. Among them are the reduced demands on potable supplies, reduced waste discharges to surface waters, and the opportunity for expansion of production. Recycled waters however, contain constituents which have the potential to cause deleterious effects to both production and the environment. Therefore, the use of recycled water for irrigation requires targetted monitoring and management to ensure the long-term sustainability of both the vineyard and the surrounding environment. Traditional monitoring techniques including water quality monitoring and soil testing can be complimented by new technologies and techniques which provide large quantities of information with relatively less labour and time. Such techniques can be used to monitor the vineyard environment to identify impacts arising from management practices, allowing vineyard managers to adjust management for sustainable production

A Visibility Analysis of the Cape Wind Project

Cape Wind has proposed a wind farm of 130 turbines on Horseshoe Shoal in the center of Nantucket Sound. A prominent concern about the project is the impact the visibility of the turbines will have on the region's tourism industry and property values. It is feared that their presence will diminish the value of the pristine coastline that has attracted vacationers to Cape Cod for generations. In this project, we assess the extent to which Cape Cod, Martha's Vineyard, and Nantucket will be visually affected by the wind farm. It was completed using a Viewshed Analysis in the GIS program, ArcMap, from the surface, mean, and maximum height of the towers. These Viewsheds were combined to give a comprehensive perspective of which areas are able to see the highest percent of the wind farm. Finally, a weighted land use value was applied to the Viewshed to account for the impact of land use on the ability to see the project. The objective of this analysis is to provide a visual representation of how great an influence the wind farm will in fact have on Cape Cod.

Biology and fertility life table of the South American fruit fly Anastrepha fraterculus on grape

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Wine classification by taste sensors made from ultra-thin films and using neural networks

This paper reports on a sensor array able to distinguish tastes and used to classify red wines. The array comprises sensing units made from Langmuir-Blodgett (LB) films of conducting polymers and lipids and layer-by-layer (LBL) films from chitosan deposited onto gold interdigitated electrodes. Using impedance spectroscopy as the principle of detection, we show that distinct clusters can be identified in principal component analysis (PCA) plots for six types of red wine. Distinction can be made with regard to vintage, vineyard and brands of the red wine. Furthermore, if the data are treated with artificial neural networks (ANNs), this artificial tongue can identify wine samples stored under different conditions. This is illustrated by considering 900 wine samples, obtained with 30 measurements for each of the five bottles of the six wines, which could be recognised with 100% accuracy using the algorithms Standard Backpropagation and Backpropagation momentum in the ANNs. (C) 2003 Elsevier B.V. All rights reserved.

A layer-by-layer film of chitosan in a taste sensor application

Chitosan is alternated with sulfonated polystyrene (PSS) to build layer-by-layer (LBL) films that are used as sensing units in an electronic tongue. Using impedance spectroscopy as the principle method of detection, an array using chitosan/PSS LBL film and a bare gold electrode as the sensing units was capable of distinguishing the basic tastes - salty, sweet, bitter, and sour - to a concentration below the human threshold. The suitability of chitosan as a sensing material was confirmed by using this sensor to distinguish red wines according to their vintage, vineyard, and brands.

EFEITO do ETHEPHON em VIDEIRA 'RUBI' (Vitis vinifera L.), CULTIVADA NA REGIÃO NOROESTE do ESTADO DE SÃO PAULO

O experimento foi conduzido em vinhedo comercial da cv. Rubi, localizado na região Noroeste do Estado de São Paulo. Teve, como objetivo, verificar o efeito do ethephon, aplicado antes da poda de produção, na porcentagem de desfolhamento, tempo de realização da poda, brotação dos ramos, produção da videira, tentando reduzir os custos, melhorando a produtividade e a qualidade. Concluiu-se que a aplicação de 7500ppm de ethephon, 20 dias antes da poda, foi o tratamento que proporcionou maior porcentagem de desfolhamento, menor tempo de realização da poda, maior porcentagem de gemas brotadas e maior produção.

Aplicação de bioestimulante nas características ampelométricas da infrutescência da videira 'Tieta'

O ensaio foi conduzido em 2003, em vinhedo de 'Tieta'. O objetivo foi avaliar o efeito de bioestimulante nas características dos cachos de uva. Foi aplicado o produto Stimulate® que contém em sua fórmula 0,09g L-1 de cinetina (citocinina), 0,05g L-1 de ácido giberélico (giberelina) e 0,05mg L-1 de ácido indolbutírico (auxina). Os tratamentos consistiram na imersão dos cachos, 15 dias após o florescimento, em solução aquosa de 0,5% do adjuvante Natura'l Óleo, acrescidos de 5 doses de Stimulate®: 0; 28; 56; 84 e 112 ml L-1. Analisaram-se o comprimento, a largura e o peso dos cachos, bagos e engaço e o diâmetro do pedicelo. O delineamento estatístico foi em blocos ao acaso, com cinco repetições. Concluiu-se que a maior massa fresca dos cachos foi obtida em função do aumento do número de bagos fixados na ráquis e da massa do engaço. O Stimulate® associado ao Natura'l Óleo provocou o aparecimento de manchas marrons nos bagos e depreciando na qualidade, diminuiu o tamanho dos bagos e atrasou a maturação dos frutos.

Flutuação populacional de adultos de Anastrepha fraterculus (Wied.) em cultivo protegido e convencional de videira

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Teores foliares de nutrientes, índice relativo de clorofila e teores de nitrato e de potássio na seiva do pecíolo na videira 'Niagara Rosada

A nutritional survey was carried out in 93 vineyards of the wine regions of Jundiai, Sao Miguel Arcanjo and Jales (state of São Paulo-Brazil), aiming to compare the nutrient concentration in leaf samples, the concentration of nitrate and potassium in the petiole sap and the relative chlorophyll index (IRC) of 'Niagara Rosada' vineyard. Leaves, blade and petiole in full bloom vines were sampled in 20 plants selected from each vineyard, and evaluations of the IRC in the leaf blade and the levels of NO3-and K in the petioles sap were realized. Macro and micronutrients concentrations were measured in leaf samples. The sampled vineyards were grouped by region of study, and each vineyard was considered as a replicate sample, totaling 45, 24 and 24 repetitions, in Jundiai, Sao Miguel Arcanjo and Jales, respectively. Sampled vineyards from the Jales region showed higher leaf concentrations of P, K, Ca, Mg, S, Fe and Mn, and also higher IRC and levels of nitrate and potassium in the petiole. These differences were related to the different rootstocks used, which were 'IAC 766', 'IAC 572' and 'Riparia of Traviu', respectively, for Jundiai, Jales and Sao Miguel Arcanjo. The differences highlight the need to adjust the concentration ranges of nutrients in leaf analysis, through regional trials, taking into account the rootstock and the region under study.

Influência de Manejos de irrigação sobre aspectos de Ecofisiologia e de produção da videira cv. Syrah / Paulsen 1103

O manejo de irrigação pode influenciar o comportamento ecofisiológico e a produção da videira. O objetivo desse trabalho, conduzido em 2010 em Petrolina – PE, no Submédio do Vale do São Francisco, foi avaliar a influência de diferentes estratégias de manejo de irrigação no potencial de água na folha e em aspectos qualitativos e quantitativos das uvas do primeiro ciclo de produção da videira cv. Syrah/Paulsen 1103. O sistema de irrigação utilizado foi gotejamento e a lâmina de água foi estimada com base na evapotranspiração da cultura. O delineamento experimental utilizado foi o de blocos casualizados, em 4 repetições e com 3 tratamentos: irrigação plena, realizada durante todo o ciclo de produção; a irrigação com déficit, onde a aplicação de água foi interrompida na fase fenológica de cacho fechado; e a irrigação com déficit controlado, onde a irrigação, também interrompida na fase de cacho fechado, foi eventualmente realizada após a interrupção, de acordo com o monitoramento da água no solo. A imposição de déficit hídrico às plantas favoreceu uma maior concentração de açúcares e a redução da acidez nos frutos, contribuindo para a melhoria da qualidade das uvas para vinificação.

Níveis e épocas de aplicação de etefon sobre a coloração e a qualidade dos frutos da uva rubi (Vitis vinifera L.), cultivada na região noroeste do Estado de São Paulo

Pós-graduação em Agronomia (Horticultura) - FCA