ESTIMATIVA DA DEMANDA DE ÁGUA DA CULTURA DA CANA-DE-AÇÚCAR IRRIGADA UTILIZANDO SENSORIAMENTO REMOTO

ESTIMATIVA DA DEMANDA DE ÁGUA DA CULTURA DA CANA-DE-AÇÚCAR IRRIGADA UTILIZANDO SENSORIAMENTO REMOTO DANIELA ARAÚJO DE OLIVEIRA1; FERNANDO BRAZ TANGERINO HERNANDEZ2; REGIANE DE CARVALHO BISPO3; RICARDO NOGUEIRA GOMES4 E ANTONIO HERIBERTO DE CASTRO TEIXEIRA5 1 Doutoranda do Programa de Pós-Graduação em Irrigação e Drenagem, UNESP, Rua José Barbosa de Barros, 1780, 18610-034, Botucatu, São Paulo, Brasil. E-mail: [email protected]. 2Professor Titular, Departamento de Fitossanidade, Engenharia Rural e Solos - DEFERS, UNESP, Avenida Brasil Sul, n° 56, Centro, 15385-000, Ilha Solteira, São Paulo, Brasil. E-mail: [email protected]. 3Professora Doutora, Colegiado de Engenharia Agronômica, UNIVASF, Rodovia BR 407, 12 Lote 543, 56300-000, Petrolina, Pernambuco, Brasil. E-mail: [email protected]. 4 Engenheiro Agrônomo, Usina Ipê - Pedra Agroindustrial, Rod. General Euclides de Oliveira Figueredo, Km 167 + 871,35 m, 16940-000, Nova Independência, São Paulo, Brasil. E-mail: [email protected]. 5 Professor Externo, Departamento de Recursos Hídricos (PRORH), UFS, Av. Marechal Rondon, s/n, Jd. Rosa Elze, 49100-000, São Cristóvão, Sergipe, Brasil. E-mail: [email protected]. 1 RESUMO O presente trabalho teve como objetivo estimar as demandas hídricas da cultura da cana-de-açúcar irrigada pelo sistema pivô central, por meio da aplicação do algoritmo SAFER (Simple Algorithm for Evapotranspiration Retrieving). O estudo foi realizado em área comercial, no município de Nova Independência - SP, compreendendo a safra de 2020/21. Foram utilizadas imagens dos satélites Landsat 8 e Sentinel 2 e dados agrometeorológicos na estimativa da relação ETa/ETo e evapotranspiração atual (ETa). Os maiores valores de ETa observados foram entre 3,4 e 4,4 mm dia-1, enquanto os maiores valores da relação ETa/ETo foram de 0,7 e 0,8 e, apesar de comportamento similar a trabalhos semelhantes, são menores que os indicados em literatura. Palavras-chave: SAFER, evapotranspiração, pivô central. OLIVEIRA, D. A.; HERNANDEZ, F. B. T.; BISPO, R. C.; GOMES, R. N.; TEIXEIRA, A. H. C. ESTIMATION OF THE WATER DEMAND OF THE IRRIGATED SUGARCANE USING REMOTE SENSING 2 ABSTRACT This work aimed to estimate the water demands of the sugarcane crop irrigated by the central pivot system, through the application of the SAFER (Simple Algorithm for Evapotranspiration Retrieving) algorithm. The study was conducted in a commercial area, in the city of Nova Independência, SP, comprising the 2020/21 harvest. Images from the Landsat 8 and Sentinel 2 satellites and agrometeorological data were used to estimate the ETa/ETo ratio and actual evapotranspiration (ETa). The highest values of ETa observed were between 3.4 and 4.4 mm day-1, while the highest values of the ETa/ETo ratio were 0.7 and 0.8, and despite similar behavior to similar works, they are smaller than those indicated in the literature. Keywords: SAFER, evapotranspiration, central pivot.

Assessment of the total precipitable water from a sun photometer, microwave radiometer and radiosondes at a continental site in southeastern Europe

In this study, we discuss the differences in the total precipitable water (TPW), retrieved from a Cimel sun photometer operating at a continental site in southeast Europe, between version 3 (V3) and version 2 (V2) of the AErosol RObotic NETwork (AERONET) algorithms. In addition, we evaluate the performance of the two algorithms comparing their product with the TPW obtained from a collocated microwave radiometer and nearby radiosondes during the period 2007–2017. The TPW from all three instruments was highly correlated, showing the same annual cycle, with lower values during winter and higher values during summer. The sun photometer and the microwave radiometer depict the same daily cycle, with some discrepancies during early morning and late afternoon due to the effect of solar zenith angle on the measurements of the photometer. The TPW from V3 of the AERONET algorithm has small differences compared with V2, mostly related to the use of the new laboratory-based temperature coefficients used in V3. The microwave radiometer measurements are in good agreement with those obtained by the radiosonde, especially during night-time when the differences between the two instruments are almost negligible. The comparison of the sun photometer data with high-quality independent measurements from radiosondes and the radiometer shows that the absolute differences between V3 and the other two datasets are slightly higher compared with V2. However, V3 has a lower dependence from the TPW and the internal sensor temperature, indicating a better performance of the retrieving algorithm. The calculated one-sigma uncertainty for V3 as estimated, from the comparison with the radiosondes, is about 10 %, which is in accordance with previous studies for the estimation of uncertainty for V2. This uncertainty is further reduced to about 6 % when AERONET V3 is compared with the collocated microwave radiometer. To our knowledge, this is the first in-depth analysis of the V3 TPW, and although the findings presented here are for a specific site, we believe that they are representative of other mid-latitude continental stations.

Assessment of the total precipitable water from a sun-photometer, microwave radiometer and radiosondes at a continental site in southeastern Europe

In this study, we discuss the differences in the total precipitable water (TPW), retrieved from a Cimel sunphotometer operating at a continental site in South-East Europe, between the Version 3 (V3) and Version 2 (V2) of the Aerosol Robotic Network (AERONET) algorithms. In addition, we evaluate the performance of the two algorithms comparing their product with the TPW obtained from a collocated microwave radiometer and nearby radiosondes during the period 2007–2017. The TPW from all three instruments was highly correlated, showing the same annual cycle, with lower values during winter and higher during summer. The Sun-photometer and the microwave radiometer depicts the same daily cycle, with some discrepancies during early morning and late afternoon due to the effect of solar zenith angle on the measurements of the photometer. The TPW from the (V3) of the AERONET algorithm has small differences compared with (V2), mostly related to the use of the new laboratory-based temperature coefficients used in V3. The microwave radiometer shows very good performance compared to the radiosondes, especially during nighttime when the differences between the two instruments are almost negligible. The comparison of the sun-photometer data with high-quality independent measurements from radiosondes and radiometer shows that the absolute differences between V3 and the other two datasets are slightly higher compared with V2. However, V3 has a lower dependence from the TPW and the internal sensor temperature, indicating a better performance of the retrieving algorithm. To our knowledge, this is the first in-depth analysis of the V3 TPW and although the findings presented here are for a specific site, we believe that they are representative of other mid-latitude continental stations.

Moving Objects Gathering Patterns Retrieving based on Spatio-Temporal Graph

Moving objects gathering pattern represents a group events or incidents that involve congregation of moving objects, enabling the analysis of traffic system. However, effectively and efficiently discovering the specific gathering pattern turns to be a remaining challenging issue since the large number of moving objects will generate high volume of trajectory data. In order to address this issue, the authors propose a moving object gathering pattern retrieving method that aims to support the retrieving of gathering patterns based on spatio-temporal graph. In this method, firstly the authors use an improved R-tree based density clustering algorithm (RT-DBScan) to index the moving objects and collect clusters. Then, they maintain a spatio-temporal graph rather than storing the spatial coordinates to obtain the spatio-temporal changes in real time. Finally, a gathering retrieving algorithm is developed by searching the maximal complete graphs which meet the spatio-temporal constraints. To the best of their knowledge, effectiveness and efficiency of the proposed methods are outperformed other methods on both real and large trajectory data.

A Spatial Resource Top-K Query Algorithm in Cyber Physical System

Cyber physical system (CPS) mainly means that the conjoining of information and physical resources. The physical elements, which could be treated as spatial resources, need be queried through information field. The key problem is how to construct spatial resource index structure and accordingly retrieving algorithm. The spatial retrieving algorithm is widely used in the Internet and moving object. The traditional spatial resource retrieving algorithms ignore the uncertain factor of the spatial resource, which is the important feature of the military resource network. This paper use an index structure named BIR-tree, based on the belief of resource, we also propose corresponding efficient and accurate top-k retrieving algorithm. On the base of traditional IR-tree, we define the resource and regional belief aiming at special spatial environment. The results of our empirical studies with an implementation of the proposed algorithm show it is capable of excellent performance.