Conference Agenda

The known Brazilian impact structures are characterized using C-band Synthetic Aperture Radar (SAR) images from Sentinel-1 satellites. After acquiring the dual-polarization (VV and VH) Ground Range Detected Dataset from a public repository, we applied standard processing techniques, including calibration, speckle noise reduction, terrain correction, and conversion of backscattering values to linear dB format. RGB visualizations of the polarimetric components were then generated. Our findings indicate that most backscattering in Brazilian impact structures is seemingly influenced by soil properties or vegetation cover, as well as locally elevated slope angles (collar of central uplift of Serra da Cangalha). However, certain features, such as silicified sandstones in the central portions of Cerro do Jarau and Serra da Cangalha, as well as structural lineaments in the Santa Marta and Vargeão Dome structures, contribute to backscattering patterns as well. Overall, our results suggest that SAR imagery can be a valuable tool for structural mapping of impact structures. As L-band radar systems (e.g., ALOS PALSAR, JERS-1) have longer wavelength and greater ability to penetrate vegetation, we recommend that the joint use of C- and L-band data could improve geological mapping of impact structures.

Wetlands are ecosystems of great importance worldwide. Global change puts pressure on these ecosystems, contributing to their degradation. Population growth and urban development are among the main problems affecting wetlands located in these areas. Therefore, this manuscript focuses on the conservation status of the Rocuant-Andalíen wetland, located in the coastal region of Biobío, in the country's second largest urban center. The study area is one of the largest coastal wetlands in south-central Chile and has undergone various anthropogenic interventions over time. The Index of Conservation Status of Shallow Lentic Ecosystems was applied to establish the conservation status/priorities of the wetlands within the study area. The ECELS, proposed by the Catalan Water Agency (2004) has been applied in Chile in previous studies. A total of 12,987 km2, the largest areas are classified as low quality (3,705 km2) or very poor quality (4,611 km2) wetlands. This result can be explained by successive human interventions over the years, as well as surface reduction. In futures perspectives environmental recovery, this index can be used as an indicator of priority macro areas.

The Amazon coast is vulnerable to solid waste pollution, which can lead to the degradation of its ecosystems and affect its biodiversity. The debris that reaches this coast has different origins and sources, with international waste coming from other countries through mainly sea-based sources. Characteristics and dynamics of litter have been studied through monitoring to establish mitigation strategies. However, there is still limited information on international waste in the region, so this work aims to map allochthonous marine litter using geographic information systems (GIS) to monitor its distribution in four municipalities of coast of Pará. The methodology includes the design of a georeferenced survey, international waste collection in the field, processing of the litter in the laboratory, and, finally, integrating the data obtained and designing an interactive map viewer. The online dashboard presents descriptive statistics of all data collected on the eight beaches of interest. In total 577 items were collected, and the characterisation led to the identification that the international litter comes mainly from Africa and Asia. There is a high incidence of plastic waste, especially mineral water bottles. The study gives visibility to a problem that affects the socio-cultural and environmental value of the region. The visual presentation of the data provides an engaging and simplified overview of allochthonous litter on beaches in Pará, allowing for adequate dissemination and awareness of international waste dynamics.

Retrieval of the soil parameters beneath a salt crust using Synthetic Aperture Radars (SARs) relies on the knowledge of the surface roughness configuration. It involves costly ground surveys or the use of informed guesses, whose accuracy is challenging to assess due to the lack of available information. We present here a fully remotely-sensed methodology that uses a combination of C- and L-band: (1) co-polarized channels at C- and L-bands for a roughness estimate and (2) dual polarized channels at L-band for the retrieval of the subsurface configuration. This SAR-based methodology is tested on an Andean salt flat where a dedicated ground survey was made. Results are promising since the use of roughness estimated for a synergy between C- and L-bands performed equally well (in terms of root mean squared error, RMSE) regarding the methodology using fieldwork estimates. The brine salinity and the water table depth both retrieved from the SAR-based methodology were overestimated with an RMSE error of 2 - 3 % and 4 - 6 ‰, respectively.

This study presents a simulation-based methodology to evaluate the radar detectability of subsurface saline layers in the Jovian moon Europa, a key target in the search for habitable environments. Improving the interpretability of radar sounding data for planetary exploration missions focused on icy bodies is essential, as radar can detect subsurface features through dielectric contrasts—key to assessing potential ocean-surface interactions. Using nine digital terrain models (DTMs) corrected via geostatistical interpolation (e.g. IDW, TIN), and dielectric properties derived from experimental data, synthetic radargrams were generated with a multilayer coherent radar simulator configured to match the REASON instrument onboard the Europa Clipper mission. The simulations incorporated ice and hydrated salt layers (e.g., MgSO₄·11H₂O) and were processed using range compression and unfocused SAR techniques. Results showed that shallow saline inclusions (between 100 and 1000m) produce strong radar reflections under approximate conditions, confirming the system’s sensitivity to dielectric contrasts. A structured dataset containing radargrams, terrain models, and metadata was assembled to support future data driven analysis.