Search

IMPACTO AMBIENTAL DA EXPANSÃO URBANA NA MICROBACIA HIDROGRÁFICA ITAPERU/ITAPOCU PETERSON RICARDO FIORIO1, BRUNA BATAGIN1, ÉRICA SILVA NAKAI1 1Departamento de Engenharia de Biossistemas, Universidade de São Paulo, Escola Superior de Agricultura “Luiz de Queiroz”. Av. Pádua Dias, 11, CEP 13.418-900, Piracicaba, Brasil. E-mail: fiorio@usp.br; bbatagin@gmail.com; ericanakai@gmail.com. RESUMO: A expansão e ocupação urbana progride simultaneamente à preocupação direcionada às questões socioambientais. Objetivo foi analisar os impactos ambientais da ocupação urbana nas Áreas de Preservação Permanente (APP) da microbacia hidrográfica do Itaperu/Itapocu, de 1940 a 2016, por meio da interpretação de fotografias aéreas e imagem de satélite do RapidEye e Cbers-4. Os buffers das APPs foram criados de acordo com as legislações vigentes. Em todos os anos, verificou-se que ocorreu a indevida utilização das áreas legalmente protegidas. De 1940 a 2016 o crescimento urbano resultou na ocupação de 6,59 ha de maciços arbóreos e em muitos casos de APPs. Houve a extinção de cinco nascentes e redução de cursos d’água devido ao avanço de áreas de cana-de-açúcar, pastagem, área urbanizada, rodovia e solo exposto. A metodologia utilizada foi adequada para a análise temporal de uma microbacia hidrográfica. Palavras-chave: gestão ambiental, área de preservação permanente, sistema de informação geográfica, uso e ocupação do solo ENVIRONMENTAL IMPACT OF URBAN EXPANSION IN A STREAM WATERSHED ITAPERU/ITAPOCU ABSTRACT: The expansion and human occupation progresses simultaneously to concern directed to the social-environmental issues. The objective was to analyse the environmental impact of urban occupation in the Permanent Preservation Areas (APPs) of the Itaperu/Itapocu stream watershed, from 1940 to 2016, through the interpretation of aerial images and RapidEye and Cbers-4 satellite images. APP buffer was created in accordance with current legislation. In all years, it has been verified an improper use of legally protected areas. From 1940 to 2016, urban growth resulted in the occupation of 6.59 ha of tree stands and, in many cases, of APPs. There was an extinction of five springs and reduction of watercourses due to the advance of sugar cane, pasture, urbanized area, highway and exposed soil areas. This methodology was satisfactory for accomplishing microwatershed temporal analysis. Keywords: environmental management, permanent preservation area, geographic information system, soil use and occupation

A ocupacao humana nas cidades progride com a preocupacao direcionada as questoes socioambientais. O crescente exodo rural e a expansao urbana, aliados a uma dependencia cada vez maior por materias-primas e a ausencia de um previo planejamento, tem ocasionado ocupacao de areas de preservacao permanente por area urbana, agricultura e pecuaria. Objetivo deste estudo foi analisar o uso e ocupacao do solo na microbacia hidrografica do corrego do Itaperu/ Itapocu, no municipio de Piracicaba (SP), do periodo de 1940 ate 2016. Neste periodo ocorreu a expansao urbana de Piracicaba, de uma populacao rural ate urbana nos dias atuais. Foram utilizadas fotografias aereas e imagens dos satelites RapidEye e Cbers-4 para uma classificacao supervisionada. A partir dos mapas gerados, foi possivel mensurar cada uso pela tabulacao cruzada para calculo do indice Kappa e exatidao global. Foram identificadas mudancas notaveis no uso e ocupacao do solo, o avanco da urbanizacao foi de 207,72 ha e da cana de acucar foi de 292,09 ha. Ao longo dos anos, houve aparecimento de uma nova classe: rodovia e desaparecimento da classe de fruticultura. Em 2016, houve diminuicao das areas de solo exposto (zero ha), pastagem (237,71 ha) e macicos arboreos (143,23 ha). Os valores da exatidao global foram entre 28 % e 74%, os indices Kappa variaram entre valores -0.009 a 0,62 nas comparacoes entre os mapas. Essa metodologia foi satisfatoria para a realizacao de uma analise temporal de uma microbacia hidrografica.

Simple Summary The whitefly Bemisia tabaci has become a primary pest in soybean fields in Brazil over the last decades, causing losses in the yield. Its reduced size and fast population growth make monitoring a challenge for growers. The use of hyperspectral proximal sensing (PS) is a tool that allows the identification of arthropod infested areas without contact with the plants. This optimizes the time spent on crop monitoring, which is important for large cultivation areas, such as soybean fields in Brazilian Cerrado. In this study, we investigated differences in the responses obtained from leaves of soybean plants, non-infested and infested with Bemisia tabaci in different levels, with the aim of its differentiation by using hyperspectral PS, which is based on the information from many contiguous wavelengths. Leaves were collected from soybean plants to obtain hyperspectral signatures in the laboratory. Hyperspectral curves of infested and non-infested leaves were differentiated with good accuracy by the responses of the bands related to photosynthesis and water content. These results can be helpful in improving the monitoring of Bemisia tabaci in the field, which is important in the decision-making of integrated pest management programs for this key pest. Abstract Although monitoring insect pest populations in the fields is essential in crop management, it is still a laborious and sometimes ineffective process. Imprecise decision-making in an integrated pest management program may lead to ineffective control in infested areas or the excessive use of insecticides. In addition, high infestation levels may diminish the photosynthetic activity of soybean, reducing their development and yield. Therefore, we proposed that levels of infested soybean areas could be identified and classified in a field using hyperspectral proximal sensing. Thus, the goals of this study were to investigate and discriminate the reflectance characteristics of soybean non-infested and infested with Bemisia tabaci using hyperspectral sensing data. Therefore, cages were placed over soybean plants in a commercial field and artificial whitefly infestations were created. Later, samples of infested and non-infested soybean leaves were collected and transported to the laboratory to obtain the hyperspectral curves. The results allowed us to discriminate the different levels of infestation and to separate healthy from whitefly infested soybean leaves based on their reflectance. In conclusion, these results show that hyperspectral sensing can potentially be used to monitor whitefly populations in soybean fields.

EnglishVis-NIR-SWIR reflectance spectra of leaf samples, collected in the laboratory, allow the calibration of predictive models to quantify their physicochemical attributes in a practical manner and without producing chemical residues. This technique should enable the development of management strategies for intensification of pasture use. However, spectral analysis performed in the laboratory may be affected by the deterioration of plant material during transport from the field to the lab, so storage methods are necessary. This research aimed to evaluate the effects of different storage methods on the spectral response of Mombasa grass leaves. Three methods were evaluated: (i) artificially refrigerated environment, (ii) humid environment, and (iii) without microenvironment control. These methods were tested in five different storage times: 2 hours, 4 hours, 8 hours, 24 hours and 48 hours. The spectral behavior of the leaves still inserted in the plant was used as a quality reference. Results showed notable changes at the earliest storage time for the treatment without microenvironment control. Both methods with microenvironment control stabilized the occurrence of spectral changes over 48 hours of the samples storage, thus both were suggested for this species. portuguesEspectros de reflectância vis-NIR-SWIR de amostras foliares, coletados em laboratorio, permitem a calibracao de modelos preditivos para quantificacao de seus atributos fisico-quimicos de maneira pratica e sem producao de residuos quimicos. Esta tecnica permite o desenvolvimento de estrategias de manejo para a intensificacao do uso de pastagens. Contudo, analises espectrais realizadas em laboratorio podem ser afetadas pela deterioracao do material vegetal durante o transporte do campo ao laboratorio, fazendo-se necessario a utilizacao de metodos de armazenamento. O presente trabalho objetivou avaliar o efeito de diferentes metodos de armazenamento na resposta espectral de folhas de capim Mombaca. Avaliou-se tres metodos: (i) ambiente refrigerado artificialmente; (ii) ambiente umido; e (iii) ao ar livre, sem controle do microambiente; assim como, cinco diferentes tempos de armazenamento: 2 horas, 4 horas, 8 horas, 24 horas e 48 horas. O comportamento espectral das folhas ainda inseridas na planta foi utilizado como referencia de qualidade. Os resultados mostraram alteracoes pronunciadas para o armazenamento ao ar livre ja nos primeiros intervalos de tempo. Ambos metodos com controle de microambiente permitiram estabilizar a ocorrencia de alteracoes espectrais ao longo das 48h de armazenamento das amostras, sendo ambos sugeridos para esta especie

Nitrogen (N) is the main nutrient element that maintains productivity in forages, it is inextricably linked to dry matter increase and plant support capacity. In recent years, high spectral and spatial resolution remote sensors, e.g., the European Space Agency (ESA)&rsquo, s Sentinel satellite missions, have become freely available for agricultural science, and have proven to be powerful monitoring tools. The use of vegetation indices has been essential for crop monitoring and biomass estimation models. The objective of this work is to test and demonstrate the applicability of different vegetation indices to estimate the biomass productivity, the foliar nitrogen content (FNC), the plant height and the leaf area index (LAI) of several tropical grasslands species submitted to different nitrogen (N) rates in an experimental area of S&atilde, o Paulo, Brazil. Field reflectance data of Panicum maximum and Urochloa brizantha species&rsquo, cultivars were taken and convoluted to the Sentinel-2 satellite bands. Subsequently, different vegetation indices (Normalized Difference Vegetation Index (NDI), Three Band Index (TBI), Difference light Height (DLH), Three Band Dall&rsquo, Olmo (DO), and Normalized Area Over reflectance Curve (NAOC)) were tested for the experimental grassland areas, and composed of Urochloa decumbens and Urochloa brizantha grass species, which were sampled and destructively analyzed. Our results show the use of different relevant Sentinel-2 bands in the visible (VIS)&ndash, near infrared (NIR) regions for the estimation of the different biophysical parameters. The FNC obtained the best correlation for the TBI index combining blue, green and red bands with a determination coefficient (R2) of 0.38 and Root Mean Square Error (RMSE) of 3.4 g kg&minus, 1. The estimation of grassland productivity based on red-edge and NIR bands showed a R2 = 0.54 and a RMSE = 1800 kg ha&minus, 1. For the LAI, the best index was the NAOC (R2 = 0.57 and RMSE = 1.4 m2 m&minus, 2). High values of FNC, productivity and LAI based on different sets of Sentinel-2 bands were consistently obtained for areas under N fertilization.

Este trabalho foi conduzido com os objetivos de avaliar a cronologia do uso da terra entre os anos de 1962 e 1995, o grau de erosão dos solos ocupados e o impacto das ações antrópicas na Microbacia Hidrográfica de Ceveiro, cujos solos estão basicamente representados por Solos Litólicos e Podzólicos Vermelho Amarelos. Para tanto, técnicas de fotointerpretação e geoprocessamento foram utilizadas permitindo uma rápida e eficiente integração entre os dados levantados. Os resultados demonstraram que a utilização de fotografias aéreas permitiu avaliar a evolução do uso da terra na área de estudo, durante um período de 33 anos, correspondente à época analisada. A cultura anual que em 1965 ocupava cerca de 42% da área, foi reduzida para 0,15% em 1995 enquanto que a cana-de-açúcar teve um acréscimo de 16% para 66% no mesmo período sendo, portanto, a grande responsável pela redução de áreas de cultura anual na microbacia. O maior crescimento da cultura de cana-de-açúcar se deu entre os anos de 1978 e 1995, com um acréscimo de 795 ha, perfazendo um total de aproximadamente 40% da área da microbacia, caracterizado principalmente pela influência dos incentivos governamentais através do Proálcool. O impacto ambiental mais facilmente destacado pela expansão da cana-de-açúcar refere-se à redução da área de espelho d'àgua, da represa responsável pelo abastecimento da Vila de Artemis, localizada na microbacia. Implantada em 1978, sua área reduziu-se de 12ha para 6ha,|devido ao assoreamento. Em relação às perdas de solo, os resultados obtidos demonstraram que o fator de erodibilidade do solo (K) foi o mais representativo para o cálculo, quando levou-se em consideração uma mesma cultura. As menores perdas foram observadas nos solos Litólicos devido a sua textura argilosa. As diferenças de perdas de solo entre as culturas são explicadas pelo fator uso-manejo, que é maior para a cultura anual em relação à cana-de-açúcar. No período analisado, ocorreu redução das áreas cuja tolerância às perdas foi estabelecida em mais de 10 vezes o valor estabelecido, devido principalmente a substituição das culturas anuais pela cana-de-açúcar. Em relação à capacidade de uso, os resultados demonstraram que 48% da área estava sendo utilizada abaixo do seu potencial, sendo que 27% estavam sendo utilizadas adequadamente e 23% de forma inadequada. O uso do sistema SAMPA possibilitou o estabelecimento de uso preferencial indicando a forma mais adequada de distribuição das áreas para as diferentes culturas This work was conducted with the objective of evaluating the chronology of the land use during the years of 1962 and 1995, the degree of erosion of the soils and the impact of the antropic actions in the Ceveiro watershed, which presents Entisols, Alfisols and Ultisols. Fotointerpretation geoprocessing techniques were used, allowing a fast and efficient integration of the data. The results showed that the use of aerial photos allowed to evaluate the evolution of the land use in the study area, during a 33 year-old period, corresponding to the analyzed time. The annual crops that in 1965 occupied about 42% of the area, was reduced to 0,15% in 1995 while the sugar-cane increased from 16% for 66% in the same period being, therefore, responsible for the reduction of the areas of annual crops in the watershad. The largest growth of the sugar-cahe occurred during the years of 1978 to 1995, with an increment of 795 ha, that is approximately 40% of the area of the watershed, due mainly to the influence of the government incentives through Proalcool. The environmental impact high1ighted by the expansion of the sugar-cane refers to the reduction of the water reserve area responsible for the provisioning of the Villa of Artemis, located in the watershed. Construced in 1978, its area reduced from 12 ha to 6 ha due to silting. In relation the soil losses, the results obtained showed that the factor of soil erodibility (K), was the most representative for the calculations, when a same culture was taken into consideration. The smallest losses were observed in the Entisols due their loamy texture. The soil loss differences among the cultures are explained by the use-management factor, that is larger for the annual cultures in relation to sugar-cane. In the analyzed period, reduction of the areas, whose tolerance to the losses were established, occurred in more than 10 times the established value, due main1y to the substitution of the annual crops by the sugar-cane. In relation to use capacity, the results showed that 48% of the area was being used below its potential, and 27% was being used appropriately and 23% in an inadequate way. The use of the system SAMP A facilitated the establishment of preferential uses indicating the adapted form of distribution of the areas for the different crops

Made available in DSpace on 2019-10-06T16:42:11Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-11-15 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) The present study was developed in a joint partnership with the Brazilian pedometrics community to standardize and evaluate spectra within the 350–2500 nm range of Brazilian soils. The Brazilian Soil Spectral Library (BSSL) began in 1995, creating a protocol to gather soil samples from different locations in Brazil. The BSSL reached 39,284 soil samples from 65 contributors representing 41 institutions from all 26 states. Through the BSSL spectra database, it was possible to estimate important soil attributes, such as clay, sand, soil organic carbon, cation exchange capacity, pH and base saturation, resulting in differences among the multi-scale models taking Brazil (overall), regional and state scale. In general, spectral descriptive and quantitative behavior indicated important relationship with physical, chemical and mineralogical properties. Statistical analyses showed that six basic patterns of spectral signatures represent the Brazilian soils types and that environmental conditions explain the differences in spectra. This study demonstrates that spectroscopy analyses along with the establishment of soil spectral libraries are a powerful technique for providing information on a national and regional levels. We also developed an interactive online platform showing soil sample locations and their contributors. As soil spectroscopy is considered a fast, simple, accurate and nondestructive analytical procedure, its application may be integrated with wet analysis as an alternative to support the sustainable management of soils. Department of Soil Science Luiz de Queiroz College of Agriculture (ESALQ) University of São Paulo (USP), Ave. Pádua Dias 11, Cx. Postal 9 Department of Soil Federal University of Santa Maria, Av. Roraima 1000 Geographical Sciences Department Federal University of Pernambuco, Av. Ac. Hélio Ramos, s/n Department of Agronomy State University of Maringá, Av. Colombo 5790 Department of Agriculture Biodiversity and Forestry Federal University of Santa Catarina, Rodovia Ulysses Gaboardi 3000 - Km 3 Federal Rural University of Amazon, Ave. Presidente Tancredo Neves 2501 Faculty of Agronomy and Veterinary Medicine University of Brasília EMBRAPA - Solos, R. Antônio Falcão, 402, Boa Viagem Center of Nuclear Energy in Agriculture (CENA) USP, Av. Centenário 303 CDRS/Secretary of Agriculture of São Paulo State, R. Campos Salles 507 Department of Soils Federal University of Viçosa, Ave. Peter Henry Rolfs s/n EMBRAPA – Informática Agropecuária, Ave. André Tosello, 209 Department of Nuclear Energy Federal University of Pernambuco, Av. Prof. Luis Freire 1000 Department of Geography Federal University of Rio Grande do Norte, R. Joaquim Gregório s/n Agronomic Institute of Campinas (IAC), Ave. Barão de Itapura 1481 Institute of Agricultural Sciences Federal Rural University of Amazônia, Ave. Presidente Tancredo Neves 2501, 66.077-830 Department of Soil Science Federal University of Lavras Federal University of Mato Grosso, Cuiabá, Av. Fernando Corrêa da Costa 2367 Department of Soils Federal Rural University of Rio de Janeiro, Rodovia BR 465, Km 07 s/n Soil and Water Sciences Department University of Florida, 2181 McCarty Hallr, PO Box 110290 EMBRAPA - Solos, R. Jardim Botânico, 1024 Department of Soils and Fertilizers School of Agricultural and Veterinary Studies São Paulo State University (FCAV-UNESP), Via de Acesso Prof. Paulo Donato Castellane s/n Federal University of Sergipe, Av. Marechal Rondon s/n Graduate Program in Earth Sciences (Geochemistry) Department of Geochemistry Federal Fluminense University, Outeiro São João Batista, s/n Federal Institute of the Southeast of Minas Gerais, R. Monsenhor José Augusto 204 Federal University of Rio Grande do Norte, R. Joaquim Gregório s/n Federal University of Piauí EMBRAPA Milho e Sorgo, Rod MG 424 Km 45 Institute of Agricultural Sciences Federal University of Jequitinhonha e Mucuri Valleys, Ave. Ver. João Narciso 1380 Department of Biosystems Engineering ESALQ USP, Ave. Pádua Dias 11, Cx. Postal 9 Federal University of Acre, Rodovia BR 364 Km 04 Federal University of Amazonas, Av. General Rodrigo O. J. Ramos 1200 EMBRAPA Clima Temperado, BR-392, km 78 Department of Agronomy Federal Rural University of Pernambuco, R. Manuel de Medeiros s/n EMBRAPA Cocais, Quadra 11, Av. São Luís Rei de França 4 Paraense Emílio Goeldi Museum, Av. Gov. Magalhães Barata 376 Exata Laboratory, Rua Silvestre Carvalho Q 11 Federal University of Rondônia, BR 364, Km 9.5 Nacional Institute for Amazonian Research, Ave. André Araújo 2936 Department of Forestry Sciences ESALQ-USP, Ave. Pádua Dias 11, Cx. Postal 9 Department of Soils and Fertilizers School of Agricultural and Veterinary Studies São Paulo State University (FCAV-UNESP), Via de Acesso Prof. Paulo Donato Castellane s/n FAPESP: 2014/22262-0 FAPESP: 2016/26176-6 FAPESP: 2017/03207-6

Nitrogen management in crops is a key activity for agricultural production. Methods that can determine the levels of this element in plants in a quick and non-invasive way are extremely important for improving production systems. Within several fronts of study on this subject, proximal and remote sensing methods are promising techniques. In this regard, this research sought to demonstrate the relationships between variations in leaf nitrogen content (LNC) and sugarcane spectral behaviour. The work was carried out in three experimental areas in São Paulo State, Brazil, with different soils, varieties and nitrogen rates during the 2012/13 and 2013/14 seasons. A significant correlation was observed between the LNC and variations in the sugarcane spectra. The green and red-edge spectral bands were the most consistent and stable predictors of LNC among the evaluated harvests. Stepwise multiple linear regression analysis (MSLR) generated better models for LNC estimation when calibrated with experimental area, independent of the variety. The present research demonstrates that specific wavelengths are associated with the variation in LNC in sugarcane, and these are reported in the green region (near 550 nm) and in the red-edge wavelengths (680 to 720 nm). These results may help in future research on the direct in situ application of nitrogen fertilizers. Nitrogen management in crops is a key activity for agricultural production. Methods that can determine the levels of this element in plants in a quick and non-invasive way are extremely important for improving production systems. Within several fronts of study on this subject, proximal and remote sensing methods are promising techniques. In this regard, this research sought to demonstrate the relationships between variations in leaf nitrogen content (LNC) and sugarcane spectral behaviour. The work was carried out in three experimental areas in São Paulo State, Brazil, with different soils, varieties and nitrogen rates during the 2012/13 and 2013/14 seasons. A significant correlation was observed between the LNC and variations in the sugarcane spectra. The green and red-edge spectral bands were the most consistent and stable predictors of LNC among the evaluated harvests. Stepwise multiple linear regression analysis (MSLR) generated better models for LNC estimation when calibrated with experimental area, independent of the variety. The present research demonstrates that specific wavelengths are associated with the variation in LNC in sugarcane, and these are reported in the green region (near 550 nm) and in the red-edge wavelengths (680 to 720 nm). These results may help in future research on the direct in situ application of nitrogen fertilizers.

The total or partial removal of sugarcane (Saccharum spp. L.) straw for bioenergy production may deplete soil quality and consequently affect negatively crop yield. Plants with lower yield potential may present lower concentration of leaf-tissue nutrients, which in turn changes light reflectance of canopy in different wavelengths. Therefore, vegetation indexes, such as the normalized difference vegetation index (NDVI) associated with concentration of leaf-tissue nutrients could be a useful tool for monitoring potential sugarcane yield changes under straw management. Two sites in S&atilde, o Paulo state, Brazil were utilized to evaluate the potential of NDVI for monitoring sugarcane yield changes imposed by different straw removal rates. The treatments were established with 0%, 25%, 50%, and 100% straw removal. The data used for the NDVI calculation was obtained using satellite images (CBERS-4) and hyperspectral sensor (FieldSpec Spectroradiometer, Malvern Panalytical, Almelo, Netherlands). Besides sugarcane yield, the concentration of the leaf-tissue nutrients (N, P, K, Ca, and S) were also determined. The NDVI efficiently predicted sugarcane yield under different rates of straw removal, with the highest performance achieved with NDVI derived from satellite images than hyperspectral sensor. In addition, leaf-tissue N and P concentrations were also important parameters to compose the prediction models of sugarcane yield. A prediction model approach based on data of NDVI and leaf-tissue nutrient concentrations may help the Brazilian sugarcane sector to monitor crop yield changes in areas intensively managed for bioenergy production.

COMPORTAMENTO ESPECTRAL DE FOLHAS DA CANA-DE-AÇÚCAR NA PRESENÇA DE DÉFICIT HÍDRICO PETERSON RICARDO FIORIO1; RUBENS DUARTE COELHO2; PEDRO PAULO DA SILVA BARROS3; MAGDA MARIA ZULETA BONILLA4 E ANA PAULA BARBOSA GADY5 1Prof. Dr., Departamento de Engenharia de Sistemas Agrícolas, Escola Superior de Agricultura “Luiz de Queiroz, Av. Pádua Dias, 11 – CEP: 13418-900, Cx. Postal 9 - Piracicaba – SP ,Brasil, email: fiorio@usp.br 2 Prof. Dr., Departamento de Engenharia de Sistemas Agrícolas, Escola Superior de Agricultura “Luiz de Queiroz, Av. Pádua Dias, 11 - CEP: 13418-900, Cx. Postal 9 - Piracicaba – SP, Brasil, email: rdcoelho@usp.br 3Pós Doutorando, Departamento de Engenharia de Sistemas Agrícolas, Escola Superior de Agricultura “Luiz de Queiroz, Av. Pádua Dias, 11 - CEP: 13418-900, Cx. Postal 9 - Piracicaba – SP, Brasil, email: pedropaulo@usp.br 4Mestra, Departamento de Engenharia de Sistemas Agrícolas, Escola Superior de Agricultura “Luiz de Queiroz, Av. Pádua Dias, 11 - Cx. Postal 9 - CEP: 13418-900, Piracicaba – SP, Brasil, email: magdazuleta@gmail.com 5Pós Doutora, Departamento de Engenharia de Sistemas Agrícolas, Escola Superior de Agricultura “Luiz de Queiroz, Av. Pádua Dias, 11 - CEP: 13418-900, Cx. Postal 9 - Piracicaba – SP, Brasil, email: anap_barbosa@yahoo.com.br 1 RESUMO O sensoriamento remoto é uma das ferramentas disponíveis atualmente aos agricultores que permite quantificar a variabilidade espacial do estado hídrico da vegetação de maneira rápida, uma vez que é uma técnica não destrutiva e de ampla abrangência para a quantificação de parâmetros biofísicos. Neste contexto, o objetivo do presente estudo foi identificar o efeito do déficit hídrico no comportamento espectral de folhas de cana-de-açúcar. O estudo foi realizado em ambiente protegido (casa de vegetação), conduzido em delineamento em blocos ao acaso (DBC), sendo os tratamentos distribuídos em três blocos, totalizando, cinco tratamentos repetidos três vezes, para um total de 60 caixas. A irrigação de cada tratamento foi feita com base na evapotranspiração acumulada (EToAc) e a umidade do solo foi monitorada utilizando tensiometria e TDR (Time Domain Reflectometer). As leituras espectrais foram realizadas utilizando o espectrorradiômetro ASD FieldSpec 3, nas quais foram mensuradas quatro plantas por caixa. Com base nos dados analisados foi possível observar variações na intensidade da reflectância entre os tratamentos quando o déficit hídrico foi imposto. Concluiu-se que as curvas espectrais dos tratamentos com mais dias após o término da irrigação apresentam reflectância mais alta, principalmente na região do infravermelho próximo. Palavras-chave: sensoriamento remoto hiperespectral; estresse hídrico; comportamento espectral; irrigação; saccharum spp. FIORIO, P. R.; COELHO, R. D.; BARROS, P. P. S.; BONILLA, M. M. Z.; GADY, A. P. B. SPECTRAL BEHAVIOR OF SUGARCANE'S LEAVES UNDER THE WATER DEFICIT CONDITIONS 2 ABSTRACT The remote sensing nowadays is an available tool for farmers that allows they quantify space variability of water vegetation state, since it is a non-destructive technique and broad fullness for quantification of vegetation biophysical parameters. In this context, the aim of this study was identify the effect of water deficit in the spectral behavior of sugarcane's leaves. The study was realized inside of protected environment (greenhouse), managing randomized blocks design (RBD), the treatments were distributed on three blocks, totalizing five treatments repeated three times by 60 boxes. The irrigation of each treatment was performed based on the accumulated evapotranspiration (ETc) and the soil humidity was monitoring by tensiometers and TDR (Time Domain Reflectometer). Spectral data were collected using ASD FieldSpec 3 spectroradiometer, it was measured four plants in each box. Based on the analyzed data it was possible observe variations in the intensity of reflectance while the water deficit was imposed. In conclusion the spectral curves of treatments with more days after finished of irrigation show highest reflectance, mainly in near infrared region. Keywords: hyperspectral remote sensing; water stress; spectral behavior; irrigation; saccharum spp.

There is a consensus about the necessity to achieve a quick soil spatial information with few human resources. Remote/proximal sensing and pedotransference are methods that can be integrated into this approach. On the other hand, there is still a lack of strategies indicating on how to put this in practice, especially in the tropics. Thus, the objective of this work was to suggest a strategy for the spatial prediction of soil classes by using soil spectroscopy from ground laboratory spectra to space images platform, as associated with terrain attributes and spectral libraries. The study area is located in São Paulo State, Brazil, which was covered by a regular grid (one per ha), with 473 boreholes collected at top and undersurface. All soil samples were analyzed in laboratory (granulometry and chemical), and scanned with a VIS-NIR-SWIR (400–2500 nm) spectroradiometer. We developed two traditional pedological maps with different detail levels for comparison: TFS-1 regarding orders and subgroups; and TFS-2 with additional information such as color, iron and fertility. Afterwards, we performed a digital soil map, generated by models, which used the following information: (i) predicted soil attributes from undersurface layer (diagnostic horizon), obtained by using a local spectral library; (ii) spectral reflectance of a bare soil surface obtained by Landsat image; and (iii) derivative of terrain attributes. Thus, the digital map was generated by a combination of three variables: remote sensing (Landsat data), proximal sensing (laboratory spectroscopy) and relief. Landsat image with bare soil was used as a first observation of surface. This strategy assisted on the location of topossequences to achieve soil variation in the area. Afterwards, spectral undersurface information from these locations was used to modelize soil attributes quantification (156 samples). The model was used to quantify samples in the entire area by spectra (other 317 samples). Since the surface was bare soil, it was sampled by image spectroscopy. Indeed, topsoil spectral laboratory information presented great similarity with satellite spectra. We observed angle variation on spectra from clayey to sandy soils as differentiated by intensity. Soil lines between bands 3/4 and 5/7 were helpful on the link between laboratory and satellite data. The spectral models of soil attributes (i.e., clay, sand, and iron) presented a high predictive performance (R2 0.71 to 0.90) with low error. The spatial prediction of these attributes also presented a high performance (validations with R2 > 0.78). The models increased spatial resolution of soil weathering information using a known spectral library. Elevation (altitude) improved mapping due to correlation with soil attributes (i.e., clay, iron and chemistry). We observed a close relationship between soil weathering index map and laboratory spectra + image spectra + relief parameters. The color composite of the 5R, 4G and 3B had great performance on the detection of soils along topossequences, since colors went from dark blue to light purple, and were related with soil texture and mineralogy of the region. The comparison between the traditional and digital soil maps showed a global accuracy of 69% for the TFS-1 map and 62% in the TFS-2, with kappa indices of 0.52 and 0.45, respectively. We randomly validated both digital and traditional maps with individual plots at field. We achieve a 75% and 80% agreement for digital and traditional maps, respectively, which allows us to conclude that traditional map is not necessarily the truth and digital is very close. The key of the strategy was to use bare soil image as a first step on the indication of soil variation in the area, indicating in-situ location for sample collection in all depths. The current strategy is innovative since we linked sensors from ground to space in addition with relief parameters and spectral libraries. The strategy indicates a more accurate map with less soil samples and lower cost.

RESUMOObjetivou-se neste trabalho caracterizar diferentes solos por espectrorradiometria de reflectância ao longo de uma topossequência na região de Piracicaba, SP. Amostras de solo foram coletadas e analisadas em campo, em laboratório de análises químicas e por sensores Vis-NIR (400-2500 nm). Alterações nos solos da topossequência foram identificáveis nas informações espectrais. Constituintes dos solos, tais como, matéria orgânica, mineralogia, formas de óxidos de ferro e granulometria foram determinantes nas variações das feições de absorção e intensidades de reflectância. Cada perfil mostrou características espectrais diferenciadoras entre horizontes, relacionadas à intensidade, feições de absorção e morfologia da curva. A avaliação morfológica não pode ser avaliada pelo sensor, sendo uma de suas limitações. Existe relação entre grau de intemperismo (índices ki, relação silte/argila e mineralogia) e dados espectrais. Isso foi observado nos solos originados de basalto, onde houve aumento do ferro extraído pelo ditionito (cristalino e amorfo) na sequência Nitossolo Vermelho Latossólico (NVL) em direção ao Cambissolo (C) e, aumento do ferro amorfo nesta mesma sequência. Na avaliação da topossequência completa observou-se a sequência de absorção centrada em 500 e 850 nm decrescente do Nitossolo Vermelho Latossólico em direção ao Chernossolo, ou seja, na sequência de decréscimo dos teores de ferro cristalino (hematita e goethita) e aumento de ferro amorfo, corroborado pelo aumento dos valores do índice ki. Houve relação entre os dados espectrais, o índice ki e a posição do solo na paisagem. Esses resultados mostram que a espectrorradiometria é uma ferramenta promissora para auxiliar o levantamento de solos. Entretanto, há necessidade do suporte à implantação de bibliotecas de dados espectrais de solos com acesso irrestrito aos usuários. ABSTRACTThe aim of this work was to characterise by reflectance spectroradiometry different soils along a toposequence in Piracicaba, in the state of São Paulo, Brazil. Soil samples were collected and analysed in the field, in a laboratory for chemical analysis and by Vis-NIR sensors (400-2500 nm). Changes in the soils of the toposequence could be identified in the spectral information. Such soil constituents as organic matter, mineralogy, types of iron oxide and particle size determined variations in absorption features and reflectance intensities. Each profile displayed distinctive spectral characteristics between horizons, related to intensity, absorption features and curve morphology. The sensor could not be used to carry out the morphological evaluation, this being one of its limitations. There is a relationship between the degree of weathering (KI indices, silt to clay ratio and mineralogy) and the spectral data. This was seen in the basalt-based soils, where there was an increase in the iron extracted by dithionite (crystalline and amorphous) for the sequence, Latosolic Red Nitosol (NVL) to Cambisol (C), and an increase in amorphous iron for the same sequence. Evaluation of the complete toposequence showed that the absorption sequence centred on 500 and 850 nm decreased from the Latosolic Red Nitosol towards the Cambisol, i.e. following the decrease in crystalline iron content (hematite and goethite) and the increase in amorphous iron. This was substantiated by increases in KI index values. There was a relationship between the spectral data, KI index and landscape position of the soil. These results show that spectroradiometry is a promising tool to assist in soil surveys. However there is a need to support the implementation of libraries of soil spectral data, with unrestricted user access.

RESUMOObjetivou-se neste trabalho caracterizar diferentes solos por espectrorradiometria de reflectância ao longo de uma topossequência na região de Piracicaba, SP. Amostras de solo foram coletadas e analisadas em campo, em laboratório de análises químicas e por sensores Vis-NIR (400-2500 nm). Alterações nos solos da topossequência foram identificáveis nas informações espectrais. Constituintes dos solos, tais como, matéria orgânica, mineralogia, formas de óxidos de ferro e granulometria foram determinantes nas variações das feições de absorção e intensidades de reflectância. Cada perfil mostrou características espectrais diferenciadoras entre horizontes, relacionadas à intensidade, feições de absorção e morfologia da curva. A avaliação morfológica não pode ser avaliada pelo sensor, sendo uma de suas limitações. Existe relação entre grau de intemperismo (índices ki, relação silte/argila e mineralogia) e dados espectrais. Isso foi observado nos solos originados de basalto, onde houve aumento do ferro extraído pelo ditionito (cristalino e amorfo) na sequência Nitossolo Vermelho Latossólico (NVL) em direção ao Cambissolo (C) e, aumento do ferro amorfo nesta mesma sequência. Na avaliação da topossequência completa observou-se a sequência de absorção centrada em 500 e 850 nm decrescente do Nitossolo Vermelho Latossólico em direção ao Chernossolo, ou seja, na sequência de decréscimo dos teores de ferro cristalino (hematita e goethita) e aumento de ferro amorfo, corroborado pelo aumento dos valores do índice ki. Houve relação entre os dados espectrais, o índice ki e a posição do solo na paisagem. Esses resultados mostram que a espectrorradiometria é uma ferramenta promissora para auxiliar o levantamento de solos. Entretanto, há necessidade do suporte à implantação de bibliotecas de dados espectrais de solos com acesso irrestrito aos usuários.

A expansão urbana é a principal responsável pela disposição atual das cidades. E hoje, sabe-se toda a importância que possui a conservação da cobertura vegetal. Pois interfere na qualidade de vida, retém partículas poluidoras e a falta dela causa desconforto térmico. Dessa forma o presente trabalho tem como objetivo analisar a relação existente entre a presença de vegetação e a temperatura média, dos bairros da cidade de Piracicaba – SP. Foi utilizado imagem do sensor Rapideye para o mapeamento e quantificação da vegetação e do Landsat 8 para quantificação da temperatura em 4 épocas diferentes do ano. A cidade de Piracicaba possui 40,44% de seu território com vegetação. Com a espacialização da temperatura pode-se observar sua variação, apresentando uma amplitude térmica de 6,4°C no outono. As áreas que apresentaram as menores taxas de áreas verdes destacaram-se com as maiores temperaturas, onde prevalece as construções verticais atreladas a reduzida cobertura arbórea.

With the development of remote sensing techniques, the understanding of soil spectral response with the purpose to assist soil mapping and estimate soil attributes, become necessary. For this, the objective of this work was to analyze the spectral response of eight soil profiles from Mogi-Guaçú (SP) region obtained in laboratory and correlate them with soil texture and their chemical and mineralogical characteristics. The soils were sampled in each horizon and radiometric data was obtained by a spectroradiometer in laboratory. It was possible to discriminate the spectral response of each soil and relate them with texture, organic matter and iron oxides content. The analysis of reflected electromagnetic energy permitted to evaluate the soils mineralogical compounds like iron oxides, kaolinite, gibbsite and 2:1 clay minerals. These results indicate that this technique can be used as an auxiliary method in soil studies and mapping. Com o desenvolvimento das técnicas de sensoriamento remoto, o entendimento da resposta espectral dos solos com a finalidade de auxiliar no mapeamento e na estimativa dos seus atributos torna-se necessária. Desta forma, este trabalho teve por objetivo analisar a resposta espectral de oito perfis de solos da região de Mogi-Guaçú (SP) obtida em laboratório, e correlacioná-la com a textura e suas características químicas e mineralógicas. Os solos foram amostrados por horizontes e os dados de reflectância foram obtidos em laboratório utilizando-se um espectroradiômetro. Foi possível diferenciar a resposta espectral de cada solo e correlacioná-la com a textura, conteúdo de matéria orgânica e teor óxido de ferro. A análise da energia eletromagnética refletida permitiu avaliar a composição mineralógica dos solos com relação aos óxidos de ferro, caulinita, gibbsita e minerais 2:1. Tais resultados indicam que a análise espectral pode ser utilizada técnica auxiliar no estudo e mapeamento dos solos.

Um grande número de amostras de solos seria necessário para delimitar com precisão os limites das unidades de solos. Assim, técnicas que possam auxiliar em levantamentos pedológicos como o sensoriamento remoto tem provado ser de grande valia. O objetivo foi avaliar a possibilidade de diferenciar solos por meio de dados espectrais em laboratório e orbitais. Para o trabalho foi escolhida uma área de 473 ha com solo exposto, proveniente de dois materiais de origem distintos, o arenito com cimento argiloso e o basalto. Foi estabelecida uma grade (100 m x 100 m) em toda a área de estudo, totalizando 473 pontos de amostragem, todos georreferenciados. Para cada ponto da grade, foram coletadas amostras de solo nas profundidades 0-20 cm (superfície, A) e 80-100 cm (subsuperfície, B). A partir dos resultados das análises químicas e físicas e descrição de perfis, gerou-se o mapa de solos, e posteriormente, cada unidade desse mapeamento foi diferenciada por textura. As reflectâncias de laboratório foram obtidas com o espectroradiômetro IRIS, na faixa de 450 a 2500 nm. As reflectâncias orbitais foram obtidas após o processamento de uma imagem TM-Landsat-5, para os pontos de amostragem. Equações discriminantes foram geradas partindo-se dos dados espectrais por tratamento estatístico, que selecionou entre as setenta variáveis espectrais em laboratório, cinquenta e seis, sendo selecionadas para o modelo espectral orbital as seis bandas reflectivas do sensor TM. As equações geradas foram testadas, obtendo-se matrizes de confusão, onde ocorreu um acerto de 81% para os dados espectrais em laboratório e 40% de concordância para os dados orbitais.

Wet chemistry methods to extract soil properties such as Fe2O3, TiO2, MnO and clay are cost effective, time consuming and environmental polluter. Moreover, a large set of samples has to be collected for precise spatial mapping. Ordinary surface soil mapping is a problematic method. Accordingly, non destructive technologies, such as remote sens- ing methods can provide important vantages. The objective of the present work was to estimate soil attributes by labora- tory and orbital sensors and compare these results with soil classification. The study area is a 473 ha bare soil field located in the region of Barra Bonita, Brazil. A sampling grid of 100 by 100 m was established and the exact position of each point was georeferenced, and sent to traditional (wet) laboratory analyses. The soil samples reflectance were also acquired by a laboratory sensor using artificial illumination (450 to 2500 nm). Over the same selected ground area reflectance data were extracted from the TM-Landsat-5 image. Prediction equations between the satellite and laboratory reflectance data and the wet chemistry were generated for each attribute. Most of the generated equations presented high and significant R 2 such as for the Fe2O3 with 0.82 for laboratory and 0.67 for the orbital reflectance data. The comparison between reflec- tance estimates and laboratory wet measurements for iron presented 92.2% success for the laboratory and 91.3% for the orbital sensors. The comparison for the texture intervals, showed 65% and 50% success for laboratory and orbital data re- spectively. The iron contents obtained by the sensors allowed to better remotely classify soil classes. Soil extractions to determine these attributes can be substitute by spectral reflectance models based on the present methodology.

Traditional soil analyses are time-consuming with high cost and environmental risks, thus the use of new technologies such as remote sensing have to be estimulated. The purpose of this work was to quantify soil attributes by laboratory and orbital sensors as a non-destructive and a non-pollutant method. The study area was in the region of Barra Bonita, state of São Paulo, Brazil, in a 473 ha bare soil area. A sampling grid was established (100 × 100 m), with a total of 474 locations and a total of 948 soil samples. Each location was georeferenced and soil samples were collected for analysis. Reflectance data for each soil sample was measured with a laboratory sensor (450 to 2,500 nm). For the same locations, reflectance data was obtained from a TM-Landsat-5 image. Multiple linear regression equations were developed for 50% of the samples. Two models were developed: one for spectroradiometric laboratory data and the second for TM-Landsat-5 orbital data. The remaining 50% of the samples were used to validate the models. The test compared the attribute content quantified by the spectral models and that determined in the laboratory (conventional methods). The highest coefficients of determination for the laboratory data were for clay content (R² = 0.86) and sand (R² = 0.82) and for the orbital data (R² = 0.61 and 0.63, respectively). By using the present methodology, it was possible to estimate CEC (R² = 0.64) by the laboratory sensor. Laboratory and orbital sensors can optimize time, costs and environment pollutants when associated with traditional soil analysis. Analises de solos tradicionais consomem tempo com alto custo e riscos ambientais. Dessa forma, o uso de novas tecnologias como o sensoriamento remoto tem sido estimulado. O objetivo do trabalho foi quantificar atributos dos solos por um método não destrutivo e não poluente utilizando sensor de laboratório e orbital. A área de estudo localiza-se na região de Barra Bonita, Brasil, com 473 ha com solo exposto. Foi estabelecida uma malha de amostragem (100 m × 100 m) com 474 pontos de amostragem e um total de 948 amostras de solos. Os pontos de amostragem foram georreferenciados, e amostras de solos coletadas e enviadas para análises. Os dados de Reflectância foram obtidos para cada amostra de solo com o sensor em laboratório (450 a 2500 nm). Nos mesmos locais de amostragem de solos, foram obtidos dados de reflectância de imagens orbitais TM-Landsat-5. Equações lineares de regressão múltiplas foram desenvolvidas com 50% das amostras. Dois modelos foram desenvolvidos: o primeiro com dados de espectroradiometria de laboratório e o segundo para os dados orbitais da imagem TM Landsat-5. O restante das amostras, 50% foram utilizadas para validar o modelo. O teste comparou os valores dos atributos quantificados pelos modelos espectrais e os determinados em laboratório (método convencional). Os maiores coeficientes de determinação para os resultados de laboratório foram para argila (R² = 0,86) e areia (R² = 0,82) e para os dados orbitais (R² 0,61 e 0,63, respectivamente). Também foi possível com o presente método estimar CTC (R² = 0,64) para o sensor de laboratório, podendo otimizar tempo, custos e poluições ambientais associadas com as análises de solos tradicionais.

Automated acquisition of soil information by remote sensing is required to improve soil evaluation. Water is one of the most important elements that interfere with spectral data, and its interaction with electromagnetic energy can help diagnose soil characteristics. The objectives of this study were 1) to evaluate spectral data of wet and dry tropical Brazilian soils with different hydration; 2) to determine a method to identify soil mineralogy; 3) to evaluate clay minerals at different moisture stages and their relationship with soil mineralogy; 4) to test remote sensing techniques for the identification and influence of moisture and, 5) to determine a model to estimate soil moisture using spectral data measured in the laboratory by a spectroradiometer (450–2500 nm). Spectral reflectance was capable of distinguishing different moisture levels. As the content of moisture increased, spectral reflectance in the soil and clay mineral samples decreased. The concavity feature of absorption bands 1400 and 1900 nm decreased during dehydration. The 2200 nm band characterized the presence of kaolinite, which was more evident under drier conditions. The spectral curves of hydrated montmorillonite and kaolinite samples presented more absorption features than those of dried samples. The evaluation of the absorption feature centered at 630 nm was sensitive to the amount of kaolinite. Our results suggest that soil mineralogy could be simultaneously evaluated with wet and dry samples. The absorption features observed for clay patterns were helpful to characterize soil mineralogy. Differences in moisture content could also be detected by the soil line technique. Moisture could be differentiated by analyzing reflectance intensity mainly at the 1550–1750 nm wavelengths. It was also possible to estimate soil moisture by a multiple regression model developed (r2 value of 0.98) with the intensity dimension of the absorption features centered at 1400, 1900 and 2200 nm. Spectral analysis gave specific soil information (moisture and mineralogy) by using unique basic information from spectral reflectance, thus providing a quick, non-destructive and non-polluting method of analysis.

O objetivo deste trabalho foi desenvolver e avaliar um método para discriminação das classes de solos a partir de suas respostas espectrais, utilizando-se um sensor em laboratório. Os dados espectrais foram utilizados no desenvolvimento de modelos estatísticos para discriminar as classes de solos de uma área no sudoeste do Estado de São Paulo. Equações discriminantes foram desenvolvidas para as 18 classes. A resposta espectral foi obtida em amostras da porção superficial e da porção subsuperficial dos solos da área de estudo, num total de 370 amostras. As amostras foram coletadas em 185 ha, com uma tradagem por ha. Os resultados demonstraram que as classes de solos podem ser individualizadas e distinguidas pela análise discriminante. A análise registrou índices de acerto acima de 80% de determinação da classe de solo avaliada. O acerto global foi de 90,71% quando se utilizaram todas as classes para a geração dos modelos, e 93,44% quando se utilizaram as dez classes com maior número de indivíduos. O teste estatístico simulado mostrou-se eficiente na análise discriminante, com taxa média de acerto acima de 91%, com erro global de 8,8%. A análise demonstrou redução na qualidade do modelo quando aplicado para um subconjunto de 20% das amostras, com erro global de 33,9%. O método auxilia na discriminação de classes de solos pela sua reflectância, devido às interações físicas com a energia eletromagnética. The objective of this study was to develop and test a discrimination method for soil classes by their spectral response (SR), using a laboratory sensor. Spectral data were used to develop statistical model for discriminating soil classes in an area at the southwest of São Paulo State, Brazil. Discriminant equations were developed for 18 soil classes. The spectral data were obtained in superficial and subsuperficial soil samples in the study area, with a total of 370 samples. The samples were collected in 185 ha, with one borehole per ha. The results showed that soil classes can be separated and delimitated by discriminant analysis. The analysis presented a classification index higher than 80% for each soil class. The global classification index was 90.71%, when all soil classes were used to develop the model, and 93.44% when most individuals classes were used. The simulated statistical test was efficient in the discriminant analysis, presenting a classification index higher than 91%, with a global error of 8.8%. The analysis demonstrated a reduction of the model quality when applied for 20% sub-group of the samples with global error of 33.9%. The method helped in the soil classes discrimination by their spectral reflectance, based on their physical interaction with electromagnetic energy.

The aim of this work was to develop a spectral reflectance (SR)-based methodology to evaluate soil types and soil tillage systems. Soil samples, located along nine toposequences with basalt and shale, were collected in Sao Paulo State, Brazil. SR of soil samples was measured with a laboratory spectroradiometer between 450 and 2500 nm. SR curves were evaluated at different depths to determine soil classes, as for conventional methods of soil classification. Soil survey maps were developed by descriptive interpretation of the spectral curves and statistical analysis as well. These maps were compared with detailed and semidetailed soil maps based on chemical, physical and mineralogical soil attributes (conventional method). Organic matter, total iron, silt, sand and mineralogy (quartz, magnetite, kaolinite and smectite) were the most important attributes influencing reflectance intensity and spectral features and allowed characterization and discrimination of soils. Strong absorption features centered at 1900 nm were related to OH molecules in free water of 2:1 minerals. Identification of soil classes was most precise when the entire spectral curve of different depths was analysed simultaneously, including features and intensities. Parent material variation along toposequences and weathering variability modified soil characteristics and its respective SR data. The detection of these alterations was essential to determine soil line demarcation. Soil line demarcation and number of soil classes detected by SR analyses were similar to the detailed soil map determined by conventional methods. SR laboratory measurements can be used as a methodology to assist soil surveys. Spectral data can also group soils under similar tillage systems.

Considering that the reflected electromagnetic energy from a soil sample interacts with many of its components (mineralogy, texture and chemical properties), remote sensing can be important to detect the presence of industry residues in the soil. An example of these residues is the largely used vinasse, originated from the production of ethanol by fermentation of sugarcane. Therefore, the objective of this study was to evaluate, using remote sensing the effect of this residue on the reflectance properties of two important tropical soils, a Typic Quartzipsament (TQ) and a Typic Argiudoll (TA) collected in Sao Paulo State (Brazil). The soil samples were treated with different doses of the residue and incubated. An Infra Red Intelligent Spectroradiometer sensor was used in laboratory. TQ presented a differentiated spectral reflectance (SR) curve in relation to TA, due to low Fe, organic matter and magnetite contents. Significant spectral differences in the reflectance intensities and absorption bands were found between both soils. The reactions of the residue with soils altered their chemical properties and increased reflectance intensity as well, according to the doses. Higher significant differences were observed in the reflectance of TQ. The proportional increase of the reflectance with doses of residue was due to the increase of calcium and potassium contents present in the product. The bands that detected residue presence in the soils were those of 760–900, 2.080–2.350, 2.350–2.500 nm for TQ, and 760–900, 1.118–1.270, 1.300–1.460, 1.550–1.750 nm for TA. Remote sensing technique as soil line was important on the detection of residue variations. The TM-Landsat data simulation presented the same behavior as in the laboratory, but less detailed. These elements contribute to the increase in reflectance not altering, however, the shape of the curves or the absorption bands. This study presents a new research trend where remote sensing can be used in agriculture as well as in environmental monitoring studies related to residues.

Precision agriculture technologies are pointing to the necessity of using sensors to collect soil information to assist in fertilizer dose evaluation. This study evaluates the effect of increasing doses of lime, thermophosphate, and organic matter on spectral reflectance of a tropical soil. We analyzed the most common tropical soil in Brazil, a medium texture Typic Haplortox occurring in the state of Sao Paulo, Brazil. Physical chemical and mineralogical analyses were carried out both before and after treatments. A spectroradiometer with a 450–2500-nm spectral range was used in the laboratory to capture spectral data. The application of increasing doses of lime increased the reflectance intensity as a result of the presence of calcium. The application of thermophosphate altered reflectance intensity primarily because of the presence of phosphorous. Organic matter reduced the reflectance when compared with the control. Chemical variations promoted by fertilizer application altered the intensity of reflected energy mainly between 826 and 2500 nm. However, there were no significant changes in soil absorption features except when applied to the organic product. The high values of determination coefficients for calcium and organic matter indicate that they can be estimated through soil-reflected energy, and, consequently, will be useful in precision farming systems. (Soil Science 2003;Volume 168: 730–747)

Soil survey maps compiled at a variety of scales (1:5,000; 1:100,000; 1:500,000) were incorporated into a GIS and compared in terms of the number of soil classes (and discrete soil units belonging ...