32 research outputs found

    Horizontal accuracy assessment of very high resolution Google Earth images in the city of Rome, Italy

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    Google Earth (GE) has recently become the focus of increasing interest and popularity among available online virtual globes used in scientific research projects, due to the free and easily accessed satellite imagery provided with global coverage. Nevertheless, the uses of this service raises several research questions on the quality and uncertainty of spatial data (e.g. positional accuracy, precision, consistency), with implications for potential uses like data collection and validation. This paper aims to analyze the horizontal accuracy of very high resolution (VHR) GE images in the city of Rome (Italy) for the years 2007, 2011, and 2013. The evaluation was conducted by using both Global Positioning System ground truth data and cadastral photogrammetric vertex as independent check points. The validation process includes the comparison of histograms, graph plots, tests of normality, azimuthal direction errors, and the calculation of standard statistical parameters. The results show that GE VHR imageries of Rome have an overall positional accuracy close to 1 m, sufficient for deriving ground truth samples, measurements, and large-scale planimetric maps

    dem extraction from archive aerial photos accuracy assessment in areas of complex topography

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    AbstractThe aim of this study is to analyze the accuracy of a Digital Elevation Model (DEM) created with photogrammetric techniques from stereoscopic pairs of aerial photos in areas with complex geomorphologic characteristics. The evaluation of DEM and derived geomorphometric parameters was conducted by comparison with other standard DEM products (i.e. TINITALY/01 and ASTER GDEM-V2) and by accuracy assessment based on Check Points (CPs). The validation process includes the comparison of elevation profiles, the calculation of DEM accuracies, and the evaluation of the effect of slope and aspect on the DEM accuracy.The produced DEM accurately represent complex terrain (RMSE = 4.90 m), thus providing information suitable for local-scale geomorphometric analysis. The obtained accuracy resulted slightly worse than TINITALY/01 (RMSE = 2.53 m), but significantly better than ASTER GDEM (RMSE = 12.95 m). These results confirm that photo-based DEM extraction can be a very competitive and precise methodology if other..

    Molecular analysis of appendiceal mucinous cystadenoma and rectal adenocarcinoma in a patient with urothelial carcinoma: a case report

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    Introduction: In this report, we present the case of a patient affected by appendiceal cystadenoma, a colorectal adenocarcinoma, and a concomitant bladder carcinoma, as well as the results of the molecular study of the most relevant mutational pathways involved in these tumors. Case presentation: A 68-year-old Italian man was admitted to our unit complaining of macrohematuria, rectorrhagia, and rectal tenesmus for about 2 months. A colonoscopy showed the presence of a rectal lesion at 11cm from the anal margin; multiple biopsies were performed and a diagnosis of moderately differentiated adenocarcinoma was made. Abdominal ultrasonography and total body computed tomography performed subsequently to stage the rectal cancer showed the presence of two round nodules, interpreted as swollen lymph nodes of neoplastic origin, at the anterior aspect of the iliopsoas muscle and a budding lesion affecting the bladder. The patient underwent transurethral biopsy of the lesion in the right retrotrigonal region; the diagnosis was grade II urothelial carcinoma. The patient underwent an open anterior rectal resection with loco-regional lymphadenectomy. An enlarged appendix and a voluminous whitish soft-tissue lesion requiring an appendicectomy were detected perioperatively. Transurethral resection of the bladder lesion was also performed. The histological examination revealed that the nodular lesions in the appendix were due to a cystadenoma. For mutation analysis, genomic deoxyribonucleic acid was isolated from tumor tissue samples; for PIK3CA mutations, screening revealed that all three samples analyzed carried mutations in exon 9. Conclusions: Appendiceal mucoceles are rare but require adequate surgical treatment, given their malignant potential and the possibility of causing peritoneal pseudomyxoma. It is essential to make a correct preoperative evaluation based on a colonoscopy rather than ultrasound and computed tomography to exclude synchronous neoplasias often associated with mucoceles and to plan the optimum surgical strategy. The association between appendiceal mucoceles and other neoplasias is relatively frequent, especially with colorectal cancer. Oncogenic activation in the PIK3CA-depending pathway may contribute substantially to the pathogenesis of the different solid tumors in the same patient

    Perspectives on “Earth Observation and GIScience for Agricultural Applications”

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    Current and future scenarios for global agricultural systems under a changing climate require innovative approaches, novel datasets, and methods for improving environmental resource management and better data-driven decision-making [...

    Estimation of evapotranspiration and crop coefficients of tendone vineyards using multi-sensor remote sensing data in a mediterranean environment

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    The sustainable management of water resources plays a key role in Mediterranean viticulture, characterized by scarcity and competition of available water. This study focuses on estimating the evapotranspiration and crop coefficients of table grapes vineyards trained on overhead "tendone" systems in the Apulia region (Italy). Maximum vineyard transpiration was estimated by adopting the "direct" methodology for ETp proposed by the Food and Agriculture Organization in Irrigation and Drainage Paper No. 56, with crop parameters estimated from Landsat 8 and RapidEye satellite data in combination with ground-based meteorological data. The modeling results of two growing seasons (2013 and 2014) indicated that canopy growth, seasonal and 10-day sums evapotranspiration values were strictly related to thermal requirements and rainfall events. The estimated values of mean seasonal daily evapotranspiration ranged between 4.2 and 4.1 mm·d-1, while midseason estimated values of crop coefficients ranged from 0.88 to 0.93 in 2013, and 1.02 to 1.04 in 2014, respectively. The experimental evapotranspiration values calculated represent the maximum value in absence of stress, so the resulting crop coefficients should be used with some caution. It is concluded that the retrieval of crop parameters and evapotranspiration derived from remotely-sensed data could be helpful for downscaling to the field the local weather conditions and agronomic practices and thus may be the basis for supporting grape growers and irrigation managers

    Capability of Sentinel-2 data for estimating maximum evapotranspiration and irrigation requirements for tomato crop in Central Italy

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    Abstract The occurrence of water shortages ascribed to projected climate change, especially in the Mediterranean region, fosters the interest in remote sensing (RS) applications to optimize water use in agriculture. Remote sensing evapotranspiration and water demand estimation over large cultivated areas were used to manage irrigation to minimize losses during the crop growing cycle. The research aimed to explore the potential of the MultiSpectral Instrument (MSI) sensor on board Sentinel-2A to estimate crop parameters, mainly surface albedo (α) and Leaf Area Index (LAI) that influence the dynamics of potential evapotranspiration (ETp) and Irrigation Water Requirements (IWR) of processing tomato crop (Solanum lycopersicum L.). Maximum tomato ETp was calculated according to the FAO Penman-Monteith equation (FAO-56 PM) using appropriate values of canopy parameters derived by processing Sentinel-2A data in combination with daily weather information. For comparison, we used the actual crop evapotranspiration (ETa) derived from the soil water balance (SWB) module in the Environmental Policy Integrated Climate (EPIC) model and calibrated with in-situ Root Zone Soil Moisture (RZSM). The experiment was set up in a privately-owned farm located in the Tarquinia irrigation district (Central Italy) during two growing seasons, within the framework of the EU Project FATIMA (FArming Tools for external nutrient Inputs and water Management). The results showed that canopy growth, maximum evapotranspiration (ETp) and IWR were accurately inferred from satellite observations following seasonal rainfall and air temperature patterns. The net estimated IWR from satellite observations for the two-growing seasons was about 272 and 338 mm in 2016 and 2017, respectively. Such estimated requirement was lower compared with the actual amount supplied by the farmer with sprinkler and drip micro-irrigation system in both growing seasons resulting in 364 (276 mm drip micro-irrigation, and 88 mm sprinkler) and 662 (574 mm drip micro-irrigation, and 88 mm sprinkler) mm, respectively. Our findings indicated the suitability of Sentinel-2A to predict tomato water demand at field level, providing useful information for optimizing the irrigation over extended farmland

    Assessment of textural differentiations in forest resources in Romania using fractal analysis

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    Deforestation and forest degradation have several negative effects on the environment including a loss of species habitats, disturbance of the water cycle and reduced ability to retain CO2, with consequences for global warming. We investigated the evolution of forest resources from development regions in Romania affected by both deforestation and reforestation using a non-Euclidean method based on fractal analysis. We calculated four fractal dimensions of forest areas: the fractal box-counting dimension of the forest areas, the fractal box-counting dimension of the dilated forest areas, the fractal dilation dimension and the box-counting dimension of the border of the dilated forest areas. Fractal analysis revealed morpho-structural and textural differentiations of forested, deforested and reforested areas in development regions with dominant mountain relief and high hills (more forested and compact organization) in comparison to the development regions dominated by plains or low hills (less forested, more fragmented with small and isolated clusters). Our analysis used the fractal analysis that has the advantage of analyzing the entire image, rather than studying local information, thereby enabling quantification of the uniformity, fragmentation, heterogeneity and homogeneity of forests

    Navigating the Path to Sustainable Oil Palm Cultivation: Addressing Nexus Challenges and Solutions

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    Global palm oil demand for energy, food, and chemical uses has led to a rapid expansion of tree plantations in Southeast Asia, Central Africa, Latin America and the Caribbean. This oil tree is the world’s most productive, highly profitable and traded vegetable oil crop, and the demand is expected to increase further in the near future. Nevertheless, oil palm expansion involves risks and nexus challenges. This work supports the idea that disruptive farming intensification, instead of land expansion, could scale up productivity, reducing the anthropogenic pressure on tropical forests and biodiversity losses. Findings from recent studies suggest that there is considerable scope for further yield improvements per hectare of palm oil with sustainable agronomic practices and farming intensification. Smallholder producers, agribusiness investors, civil society actors, NGOs, governments, researchers, and industry should make coordinated efforts with regulatory and support schemes and landscape design to increase yield and productivity with sustainable management practices and to achieve zero deforestation by protecting ecosystems

    Assessment of the Agronomic Feasibility of Bioenergy Crop Cultivation on Marginal and Polluted Land: A GIS-Based Suitability Study from the Sulcis Area, Italy

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    In the context of environmental sustainability there has been an increasing interest in bioenergy production from renewable resources, and is expected that European biofuel production from energy crops will increase as a consequence of the achievement of policy targets. The aim of this paper is to assess the agronomic feasibility of biomass crop cultivation to provide profitable renewable feedstocks in a marginal and heavy-metal polluted area located in the Sulcis district, Sardinia (Italy). Results from literature review and unpublished data from field trials carried out in Sardinia were analysed to establish the main agronomic traits of crops (e.g., yield potential and input requirements). A Geographical Information System (GIS)-based procedure with remotely sensed data is also used to evaluate the land suitability and the actual land use/cover, considering a future scenario of expansion of energy crops on these marginal areas avoiding potential conflicts with food production. The results of the review suggests that giant reed, native perennial grasses and milk thistle are the most suitable energy crops for this area. The land suitability analysis shows that about 5700 ha and 1000 ha could be available for feedstock cultivation in the study area and in the most polluted area, respectively. The results obtained from land suitability process and agronomic evaluation will serve as a base to support technical and economical feasibility studies, as well as for the evaluation of environmental sustainability of the cultivation in the study area
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