Ano de publicação: 2011

O Brasil, o maior produtor mundial de cana-de-açúcar, é responsável por 35% da produção mundial. A produção de cana-de-açúcar se concentra nas regiões Centro-Sul e Nordeste e ocupa cerca de 8 milhões de hectares. A cana-de-açúcar, por apresentar um ciclo semi-perene, é influenciada pela variação das condições meteorológicas durante um ano inteiro. O objetivo do trabalho foi analisar os dados climáticos obtidos pelo modelo Eta (2011 a 2090) e os dados do clima atual (1991 a 2010) verificando suas implicações em relação a expansão da cana-de-açúcar no estado de São Paulo. Foram utilizados dados de precipitação e temperatura média, de 1991 a 2010, de estações meteorológicas de seis municípios de São Paulo. Para representar o cenário futuro (2011 a 2090), foram utilizados dados de precipitação e temperatura média obtidos pelo modelo Eta. A partir do balanço hídrico foi possível calcular a deficiência hídrica e o excedente hídrico para os municípios selecionados com armazenamento de água disponível no solo de 100mm. O balanço hídrico mostrou que haverá um aumento na deficiência hídrica. Com o aumento do período seco e do aumento da temperatura média poderá ocorrer uma queda na produtividade de sacarose da cana-de-açúcar.

water balance, Eta model, mean temperature

analise-comparativa-do-clima-atual-e-futuro-para-avaliar-a-expansao-da-cana-de-acucar-em-sao-paulo-02061715.pdf

http://www.cpa.unicamp.br/alcscens/docs/publicacoes/Analise%20comparativa%20do%20clima%20atual%20e%20futuro%20para%20avaliar%20a%20expansao%20da%20cana-de-acucar%20em%20Sao%20Paulo%20.pdf

Ano de publicação: 2011

Extremos de temperatura durante a fase do florescimento do café arábica causam abortamento de flores e perda na produção. Estudos de projeção climática, normalmente baseados em modelos de baixa resolução, já demonstram perdas na produção de café como conseqüência das altas temperaturas. No entanto, esses estudos têm uma menor precisão nas respostas por causa da resolução dos modelos, e novos estudos baseados em modelos de melhor resolução se tornam necessários. Este trabalho apresenta uma análise das implicações dos extremos de temperatura e precipitação na aptidão climática em municípios tradicionalmente produtores de café em Minas Gerais e São Paulo, utilizando o modelo climático Eta (40km de resolução). Primeiramente, as respostas do modelo foram comparadas com os dados climáticos atuais (dados observados). As projeções do modelo Eta foram satisfatórias porque seguem o padrão do clima já existente. Os dados do modelo demonstram um deslocamento do maior déficit hídrico do ano para o mês de setembro. O modelo projeta cenários com aumento de temperaturas, principalmente nos meses de setembro e outubro, que é o florescimento do café, impactando a produção de café arábica.

Aptidão climática, Café arábica, Eta

analise-dos-dados-de-projecao-climatica-do-modelo-eta-e-suas-implicacoes-para-a-cultura-do-cafe-arabica-02061715.pdf

Ano de publicação: 2013

Coffee is one of the most important crops in Brazil. Monitoring the crop is necessary to understand future production and a sound understanding of coffee's biophysical properties improves such monitoring. Biophysical properties such as dry biomass can be estimated using remote sensing, including the new generation of high-resolution images (GeoEye-1, for instance). In this study we aim to investigate the relationship between vegetation indices (VI) of high-resolution images (GeoEye-1) and coffee biophysical properties, including dry biomass and carbon. The study also aims at establishing an empirical relationship between remote sensing data (vegetation indices), simple field measurements and dry biomass, allowing calculation of coffee biomass and carbon without resorting to destructive methods. Individual GeoEye-1 satellite's bands (NIR, RED and GREEN) showed significant correlation with biomass, but the best correlation occurred with vegetation index. There is a strong correlation between NDVI, RVI, GNDVI and dry biomass, allowing the estimation of coffee crops' carbon stock. RVI had correlation with plant area index (PAI). The empirical correlation was established and the forecast equation of coffee biomass was created.

Correlation, Biomass, Vegetation mapping, Carbon, Indexes, Remote sensing, Agriculture

http://ieeexplore.ieee.org/document/6520004/

Ano de publicação: 2014

This case-study article presents the results from a morphology analysis of a knowledge and information network, focusing on the coordination mechanisms employed to generate a convergent arrangement. Agritempo was the first information system to offer (in 2003) free access to a broad range of agrometeorological data comprising all the Brazilian territory, representing an important technological innovation to the agricultural sector. To study this phenomenon an analytical framework of the Techno-Economic Network (TEN) and concepts from the Innovation Sociology field was employed. Results indicate that the durability of this arrangement - from 2003 to 2014 - can be explained by the effectiveness of the coordination strategies established in the network such as: trust based relationships; institutional and individual leadership actions; contracting; software applications and shared common working procedures.

techno-economics networks; innovation; agrometeorology; information and communication technology.

https://scielo.conicyt.cl/scielo.php?script=sci_arttext&pid=S0718-27242014000100010&lng=en&nrm=iso&tlng=en

Ano de publicação: 2015

Leaf area index (LAI) and above ground biomass (AGB) are two parameters that are difficult to measure but very useful. In this paper we investigated the relationship between coffee biophysical properties and LAI and AGB in two coffee production systems: full sun (FS) and shaded with macadamia nuts (SH). The paper proposes an empirical relationship for calculating coffee AGB and coffee LAI which avoids destructive methods, using simple field measurements and agrometeorological data. Here, we reported that LAI is related to canopy structure but subject to strong seasonal variations, which can be identified using water requirements satisfaction index (WRSI). Coffee LAI answers to the decreased WRSI with 1 month lag (WRSI-1) and LAI values decreases more for FS systems than for SH systems during dry periods. The best empirical model to predict LAI for FS coffee production system was based on canopy height (ch) and WRSI-1 value. For SH systems, the best model used ch, WRSI-1 and the height of the first pair of branches. Coffee AGB values were measured using destructive analyses and an empirical equation was developed. Both coffee production systems stocked carbon, whereas the SH system stocked an increased carbon amount provided by the macadamia trees that contributed with 15 % of the total carbon above ground. Both systems can be considered mitigation techniques since they are able to remove atmospheric carbon and stock it in the biomass, which has been largely proposed as a compensation mechanism for greenhouse gas emissions.

Carbon stock; Coffee shaded system; Empirical equations; Seasonal LAI variation 

https://link.springer.com/article/10.1007%2Fs10457-015-9799-5

Ano de publicação: 2014

Given a large image set, in which very few images have labels, how to guess labels for the remaining majority? How to spot images that need brand new labels different from the predefined ones? How to summarize these data to route the user’s attention to what really matters? Here we answer all these questions. Specifically, we propose QuMinS, a fast, scalable solution to two problems: (i) Low-labor labeling (LLL) – given an image set, very few images have labels, find the most appropriate labels for the rest; and (ii) Mining and attention routing – in the same setting, find clusters, the top- outlier images, and the  images that best represent the data. Experiments on satellite images spanning up to 2.25 GB show that, contrasting to the state-of-the-art labeling techniques, QuMinS scales linearly on the data size, being up to 40 times faster than top competitors (GCap), still achieving better or equal accuracy, it spots images that potentially require unpredicted labels, and it works even with tiny initial label sets, i.e., nearly five examples. We also report a case study of our method’s practical usage to show that QuMinS is a viable tool for automatic coffee crop detection from remote sensing images.

Low-labor labelingSummarizationOutlier detectionQuery by exampleClusteringSatellite imagery

https://www.sciencedirect.com/science/article/pii/S0020025513008001?via%3Dihub