Análisis espacial y multitemporal de la cobertura y uso del suelo con base en imágenes de satélites en la subcuenca Río Dipilto, Nueva Segovia, Nicaragua (1993, 2000, 2011)

La cuantificación del cambio de uso del suelo presenta aún altos niveles de incertidumbre, lo que repercute por ejemplo en la estimación de las emisiones de CO 2 . En este estudio se desarrollaron métodos, basados en imágenes de satélite y trabajo de campo, para estimar la tasa de cambio de la cobertura y uso del suelo, y las emisiones de CO 2 en la subcuenca río Dipilto, Nueva Segovia. La superficie de los tipos de vegetación se determinó con imágenes Landsat. Se utilizaron datos de carbono de nueve parcelas de muestreo en bosque de pino que fueron correlacionadas, para establecer un modelo de regresión lineal con el objetivo de estimar el Stock de Carbono. La sobreposición y algebra de mapas se utilizó para el escenario de emisiones de CO 2 . El análisis con imágenes de los años 1993, 2000 y 2011 reveló que durante es tos 18 años la velocidad a la que se perdieron los bosques latifoliados cerrado fue variable. Durante los primeros 7 años (1993 a 2000) se registró un aumento de 99.95 ha , que corresponde a una tasa de deforestación de - 1.45 % anual. Durante los últimos once años (2000 a 2011) esta cantidad cambió totalmente, ya que se eliminaron 331.76 h a , que corresponde a una tasa de deforestación anual de 3.41 %. Finalmente considerando el periodo de análisis, se transformaron más de 232.01 h a por año, correspondiente a u na tasa de deforestación anual de 1.55 %. La imagen de 2011 demostró que las reservas o Stock de C oscila entre 40 - 150 t/ha. Este intervalo de valores fue estimado por un modelo de regresión con razonable ajuste (R2 = 0.73 ), cuyas variables independientes fueron la reflectancia de las distintas bandas como índices de vegetación e infrarrojo cercano. Las pérdidas de C se estimaron en intervalos 1 - 191 t/h a en 20.76% del área. El 32.85% del área se mantuvo estable y 46.39% ganancias de 1 - 210 t/ha. La combinación de imágenes de resolución espacial media como son las de la serie Landsat para definir trayectorias de cambio de la cobertura del suelo, es una opción viable para la solución de interrogantes relacionadas con el cambio climático, tales como la estimación de las emisiones de CO 2 derivadas del cambio de uso del suelo.

Análisis multitemporal mediante el uso de imágenes del satélite Landsat.

Se presenta un estudio de imágenes de satélite, en el marco del programa GLOBE. El objetivo ha sido analizar los cambios producidos en el territorio de la comarca del Bajo Cinca (Huesca), utilizando dos imágenes LandSat con un intervalo de dieciséis años en el tiempo. Como resultado se elabora un mapa de cambios producidos en tres categorías, zonas sin cambios, zonas en las que la actividad fotosintética ha aumentado en su mayor parte a regadíos y a saucedales y zonas en las que ha disminuido la actividad fotosintética .

Geoprocessamento aplicado a gestão de informações territoriais do município de Grossos-RN :estudo multitemporal do uso e ocupação do solo

The present work was carried through in the Grossos city - RN and had as main objectives the elaboration of an physicist-ambient, socioeconomic survey and execution a multisecular evaluation of 11 years, between 1986 and 1996, using remote sensing products, to evaluate the modifications of the land use, aiming at the generation of an information database to implementation a geographical information system (GIS) to management the this city. For they had been in such a way raised given referring the two Demographic Censuses carried through by the IBGE (1991 and 2000) and compared, of this form was possible to the accomplishment of an evaluation on the demographic aspects (degree of urbanization, etária structure, educational level) and economic (income, habitation, vulnerability, human development). For the ambient physical survey the maps of the natural resources had been confectioned (simplified geology, hydrography, geomorphologi, veget covering, ground association, use and occupation), based in comments of field and orbital products of remote sensoriamento (images Spot-HRVIR, Landsat 5-TM and IKONOS - II), using itself of techniques of digital picture processing. The survey of these data and important in the identification of the potentialities and fragilities of found ecosystems, therefore allows an adequate planning of the partner-economic development by means of an efficient management. The project was part of a partnership between the Grossos city hall the municipal City hall of Grossos - RN and the Geoscience post-graduate program of the UFRN, more specifically the Geomatica laboratory LAGEOMA

Análise caracterização da dinâmica da Foz do Rio Apodi, região de Areia Branca/RN, com base na cartografia temática multitemporal de produtos de sensores remotos

The study area islocated in the northern cost of Rio Grande do Norte State, preciselyin a west zone of Apodi-Mossoró River, inclunding Tibau City, Grossos City and part of Mossoró City. Geologicaly, this area is composed by rokcs of Potiguar basin, represented by Cretaceous, Tertiary and Quaternary sediments. This area is characterizer by the intense action of cosatal processes (eolic and costal tranports, generalized erosion, alteration in the sediments balance and coast modification), reponsable for it´s morfological instability, also the antropic interference, where the iol industry is located, next Mossoró City, and also the salt exploration industry and the tendency of expantion of shrimp cultivation. This report had as objective the multitemporalgeoenvorimentalmonitoring of the region by recognizingin the field and analizingimages of orbital sensors of diferents years of last four decades. This analisys was achieved by Digital Images Procesing (DIP) thecnics, com subsidized, in a GIS, the preparion of Thematic Maps of natural resources (Geology, Geomorphology and Use & Ocupatios of Earth) and the Envorimental Sensivity to Oil Spilling, main objective os this project. Such technics constitute important tools of envoriment monitoring and maneging, indicating tendencies of antropic of natural growing, making possible the apropiated planning of development of the region, where the steps can be indicated minimized possibles envorimental impacts caused by antropics interferencies on the region, mainly those related to industrial activities, and oil industry above all. Researchs of this nature are very important to the analisys and ordered manegements of use and ocupation of coastal places

Análise multitemporal dos elementos geoambientais da região da Ponta do Tubarão, área de influência dos campos petrolíferos de Macau e Serra, município de Macau/RN

The study area is inserted in Ponta do Tubarão region, Macau City, setentrional littoral of Rio Grande do Norte State, composed of Tertiary and Quatemary sedimentary rocks and sediments. This region is characterized for the intense action of the coastal processes, causing the morphologic instability in part of the area, beyond the interference of human activities, as the Petroliferous Industrial Polo, salt companies and shrimp farms. This justifies the integration of multidisciplinary and multitemporal detailed scientific studies dealing with the evaluation of the changing behavior of this coastal environment by geoenvironments elements characterization, identifying protected and recuperation areas, mainly those under socioeconomic intervention. The main objective was the coastal monitoring using geoprocessing techniques to prepare thematic maps useful for oil spilling environment risk areas survey. The methodology was based on multitemporal interpretation of remote sensing images and field checking, integrated in a Geographical Information System (GIS). The Geologic, Geomorphologic, Vegetation, Soil and Land Use maps were prepared, and later on they allowed the generation of the Natural Vulnerability and Environmental Vulnerability maps. These maps had been classified in accordance with vulnerability degrees: very low, low, medi um, high and very high. Beyond these maps the GIS allowed the analysis of the shoreline evolution for 10 distinct dates, using Landsat 5 TM and 7 ETM+ and SPOT-HRVIR images. This analysis made possible the attendance of the coastal morphodynamic evolution, where the results had been represented by areasof erosion and accretion (or deposition) of sediments, pointing critical areas under erosive process to the petroliferous industry (Macau and Serra fields). The GIS also provided to prepare the Environmental Sensitivity Maps of Oil Spill (SAO Maps) in operational scale (1: 10.000), according to the norms ofthe Ministério do Meio Ambiente (MMA 2002). The SAO Map in operational scale was based on IKONOS images mosaic where the ESI (Environmental Sensitivity Index) was represented according with two tides phases of theregion. Therewere recognizedfiveESI (3, 4,7,9, 1O) for the low tide; to the high tide the ESI number increased to seven (3, 4, 5, 7, 8, 9, 10). All these information are necessary to the decisions making about oi! spill and its derivatives containment. These techniques application makes possible the optimization and implantation ofnew socioeconomics activities of low environmental impact, indicates areas for better productivity and security exploration, and benefits local communities with fauna and flora preservation. The development of these activities is inserted in the scope of Monitoramento Ambiental de Áreas de Risco a Derrames de Petróleo e Seus Derivados Cooperation Project (Rede 05/01 - PETRORISCO, FINEP/CTPETRO/PETROBRAS) of multidisciplinary and interinstitucional characteristics dealing with subjects involving the environmental monitoring and the petroliferous activity

Estudo multitemporal da dinâmica espacial do estuário Potengi/RN, utilizando como base os dados de Sensoriamento Remoto.

This work was developed in the Potengi river estuary, northern coastal city of Natal, located in the State of Rio Grande do Norte. The objective was to study the dynamics of Multitemporal Space in that estuary, however, analyze how this environment has behaved during the years 1988, 1994 and 2006. The definition of that, there was the fact that during that period, which occurred in that area and more intensive space exploration to practice economic activities as well as a greater and more rapid expansion of urban area. This study was supported by the Remote Sensing, who have been shown today, as an efficient analysis of the environmental studies, through geoprocessing techniques. From the performed analysis it was found that occurred during the period of study (1988 to 2006), a huge change in the design of the estuary of Potengi river. The figures showed the area of vegetation was decreased 65.22%, the deforested area increased by 70.44% and the shrimp activity grow 452.07% and the urban area was increased in 52.65% along that period described. Considering the numbers shown there that the process of occupying space in that area requires attention, because it is an environment that represents a huge contribution to the ecological balance.

Avaliação da aplicabilidade de sistema computacional de visualização de imagens aéreas de alta resolução em tempo real e multitemporal à degradação do rio Corumbataí

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Avaliação de áreas deposicionais e erosivas em cabos lamosos da zona costeira Amazônica através da análise multitemporal de imagens de sensores remotos

Os cabos lamosos Cassiporé e Orange no norte do Brasil constituem um ambiente dinâmico influenciado pelo rio Amazonas, onde as modificações na linha de costa estão sujeitas a severos processos de progradação e erosão. Imagens de sensores remotos ópticos e microondas foram coletadas de 1980 a 2003 e analisadas em um Sistema de Informação Geográfica (SIG), permitindo a identificação e quantificação da distribuição espacial das áreas de progradação e retrogradação ao longo da linha de costa. Durante este período, as maiores taxas de erosão ocorreram junto ao cabo Cassiporé, com recuo médio de 27,5 metros de distância linear e erosão de 1,37 km² de área de manguezal por ano. Por outro lado, os maiores índices de deposição de sedimentos ocorreram no cabo Orange, onde a planície costeira progradou 24,6 m ao ano, agregando 55,85 km² de manguezal à linha de costa nos últimos vinte e três anos. Os mecanismos de progradação determinaram um acréscimo na vegetação de manguezal de 50,8% ao longo das três últimas décadas. Um balanço sedimentar realizado na área pesquisada demonstrou que predominam os processos construtivos (61,3%) sob os processos erosivos (38,7%).

A multisensor, multitemporal approach for monitoring herbaceous vegetation growth in the Amazon floodplain

The Amazon River floodplain is an important source of atmospheric CO2 and CH4. Aquatic herbaceous vegetation (macrophytes) have been shown to contribute significantly to floodplain net primary productivity (NPP) and methane emission in the region. Their fast growth rates under both flooded and dry conditions make herbaceous vegetation the most variable element in the Amazon floodplain NPP budget, and the most susceptible to environmental changes. The present study combines multitemporal Radarsat-1 and MODIS images to monitor spatial and temporal changes in herbaceous vegetation cover in the Amazon floodplain. Radarsat-1 images were acquired from Dec/2003 to Oct/2005, and MODIS daily surface reflectance products were acquired for the two cloud-free dates closest to each Radarsat-1 acquisition. An object-based, hierarchical algorithm was developed using the temporal SAR information to discriminate Permanent Open Water (OW), Floodplain (FP) and Upland (UL) classes at Level 1, and then subdivide the FP class into Woody Vegetation (WV) and Possible Macrophytes (PM) at Level 2. At Level 3, optical and SAR information were combined to discriminate actual herbaceous cover at each date. The resulting maps had accuracies ranging from 80% to 90% for Level 1 and 2 classifications, and from 60% to 70% for Level 3 classifications, with kappa values ranging between 0.7 and 0.9 for Levels 1 and 2 and between 0.5 and 0.6 for Level 3. All study sites had noticeable variations in the extent of herbaceous cover throughout the hydrological year, with maximum areas up to four times larger than minimum areas. The proposed classification method was able to capture the spatial pattern of macrophyte growth and development in the studied area, and the multitemporal information was essential for both separating vegetation cover types and assessing monthly variation in herbaceous cover extent.

Análise multitemporal de indicadores geoambientais como subsídio ao plano de gestão ambiental - Floresta Nacional de Ipanema - SP

The objective of this research was to conduct an analysis of multitemporal landscape Ipanema National Forest, located in the municipalities of Iperó, Capela do Alto and Araçoiaba da Serra – São Paulo estate, Brazil, considering the scenarios of 1965, 2007 and 2011. The multitemporal analysis, using aerial photographs and satellite images, contributed to the contextualization and spatialization of the evolution of the landscape area. Through analysis interpretation of the images, performed by means of supervised classification were obtained thematic maps of the area, equivalent to approximately 53 km2. Through geoprocessing techniques, especially Geographic Information Systems, it was possible the integration and manipulation of data, both spatial and statistical, allowing integrated analysis of data from the entire area of the National Forest of Ipanema. As the main result, we found that the Ipanema National Forest is in landscape evolution positive, with those 46 years examined the increase of native heavy foliage areas. Increasing from 7.1 km2 of the total area of dense vegetation in 1965 to 35.9 km2 in 2011. Overall, it was possible to realize a scenario landscape quite optimistic about the evolution of forest conservation area

Análise-multitemporal da paisagem, potecialidades e fragilidades sob a ótica do uso e ocupação: destaque para as terras da Alta Bacia do Rio Taboco-MS

Pós-graduação em Geografia - IGCE

Imagens digitais aplicadas no estudo da análise multitemporal do uso e ocupação do solo numa microbacia

The knowledge of the soil occupation as for his nature, location, occurrence form, changes happened in certain periods, they are valuable for the programming of activities that you seek to the development agricultural, economical and social of the area. This work aimed at to identify and to quantify the soil occupation of Stream Petiço Watershed - Botucatu (SP), through the Geographical Information System IDRISI and data of sensor Landsat 5 TM of 09/06/97 and 23/08/2013. For the analysis of the results it was verified that the eucalyptus culture, due to existence of great reforestation companies in the watershed, together with the native forests they are predominant in the study area, the remaining of the area is occupied by pastures and soil prepared for the planting of agricultural cultures.

Multitemporal assessment of the geomorphologic evolution of the Restinga of Marambaia, Rio de Janeiro, Brazil

The Restinga of Marambaia is an emerged sand bar located between the Sepetiba Bay and the South Atlantic Ocean, on the south-east coast of Brazil. The objective of this study was to observe the geomorphologic evolution of the coastal zone of the Restinga of Marambaia using multitemporal satellite images acquired by multisensors from 1975 to 2004. The images were digitally segmented by a region growth algorithm and submitted to an unsupervised classification procedure (ISOSEG) followed by a raster edit based on visual interpretation. The image time-series showed a general trend of decrease in the total sand bar area with values varying from 80.61km(2) in 1975 to 78.15km(2) in 2004. The total area calculation based on the 1975 and 1978 Landsat MSS data was shown to be super-estimated in relation to the Landsat TM, Landsat ETM+, and CBERS-2 CCD data. These differences can also be associated to the relatively poorer spatial resolution of the MSS data, nominally 79m, against the 20m of the CCD data and 30m of the TM and ETM+ data. For the estimates of the width in the central portion of the sand bar the variation was from 158m (1975) to 100m (2004). The formation of a spit in the northern region of the study area was visually observed. The area of the spit was estimated, with values varying from 0.82km(2) (1975) to 0.55km(2) (2004).