Biomonitoring of air quality in the Bodoquena microregion, Mato Grosso Do Sul: mutagenic and morphoanatomical alterations in Tradescantia pallida (rose) D.R. Hunt var. purpurea

The objective of this study was to assess air quality in relation to vehicular traffic flow in cities located at different elevations in the Bodoquena microregion, state of Mato Grosso do Sul, Brazil. To do so, a micronucleus test was carried out using the TRAD-MCN bioassay on young Tradescantia buds collected from February to November 2018 in seven cities of the microregion with different traffic flow intensities. Meteorological parameters were evaluated, and vehicular traffic was counted to determine traffic flow in each city. With data from the Shuttle Radar Topography Mission (SRTM) and processing in Esri ArcGIS® software version 10.5.1, the regions was mapped based on an Elevation Model. Morphoanatomical analyses were performed according to standard methodology. Measurements were taken of thickness, length and width of tissues and structures, including the upper and lower cuticle, upper and lower epidermis, hypodermis and mesophyll. The greatest traffic flow was found in the cities of Bodoquena, Guia Lopes da Laguna, Jardim, and Porto Murtinho, with the period from 5:00 to 6:00 p.m. showing the highest traffic flow. The greatest frequency of mutagenic alterations was found in the city of Guia Lopes da Laguna, although the results did not differ significantly from Bonito, Caracol, and Jardim. Throughout the biomonitoring, the summer and autumn seasons showed the greatest micronuclei frequencies in all evaluated cities. Variations in the tissue/structure thickness was observed across cities and seasons, but with a decrease in thickness during autumn. In general, the tissues/structures were smaller for the cities of Nioaque and Porto Murtinho, while the anatomical and morphological characteristics of leaf length and thickness showed no differences among cities. We found limited correlation between micronuclei frequency and traffic flow, supporting the hypothesis that although mutagenic alterations are observed in T. pallida, in this microregion the changes are numerically lower when compared to other regions of the state. In light of the genotoxic and morphoanatomical factors assessed herein, the Bodoquena microregion appears to be well preserved in terms of air quality, presenting low micronuclei frequency and a limited reduction in tissues and leaf structures, regardless of the season.

Future Large Earthquake Analysis of Sulawesi Island Using Satellite Images and Moment Tensor Solution Approach

Sulawesi Island is the active tectonic region, where the tectonic architecture and potential earthquake sources until now remain largely unknown. The worst earthquake, an Mw 7.5 on September 28, 2018, in Palu, Indonesia, was caused catastrophic damage to life and property. The earthquake has highlighted the urgent need to raise knowledge of the cause of possible large future earthquakes and vulnerability. The main objective for this project is to create a thorough earthquake probabilistic hazard analysis map of the region, which is presently unavailable to better prepare for future earthquakes. The neotectonic and structural map was created using was supplemented with the 30-m resolution Shuttle Radar Topography Mission, Centroid Moment Tensor (CMT) solution, and seismologic data. The results demonstrate that faulting controls the geometry and the majority of these faults are active and capable of causing medium to large magnitude earthquakes with moment magnitudes ranging from 6.2 to 7.5 from 44 seismic sources. Our results show Sulawesi's northern deformation regimes have high seismicity risk and vulnerability. This study contributes a realistic seismic source for the Sulawesi neotectonic area particularly at the northwest, north, and east deformation regime, to understand the key large future earthquakes.

Geomorfologia estrutural e compartimentação geomorfológica obtidas através de dados aeromagnéticos e SRTM na porção Oeste do Batólito Ipojuca-Atalaia, Província Borborema, Nordeste do Brasil

O uso e interpretação de dados e imagens obtidos através de sensores remotos permitem importantes aplicações nas geociências. Neste artigo, foram utilizados dados aeromagnéticos e SRTM (Shuttle Radar Topography Mission) com resolução de 30 metros para, respectivamente, capturar indicadores geológicos e geomorfológicos na porção oeste do Batólito Ipojuca-Atalaia. Técnicas de geoprocessamento foram utilizadas para correlacionar os fatores geológicos e geomorfológicos e como produto final obter a compartimentação geomorfológica da área. Para tanto, aplicou-se as metodologias de extração da hipsometria, grau de declividade, imagem sombreada e drenagem no MDT (modelo digital de terreno) do SRTM, além dos filtros da amplitude do sinal analítico (ASA) e da primeira derivada vertical (DZ) nos dados aeromagnéticos. Como resultado foi possível distinguir nove compartimentos geomorfológicos distintos, enquadrados em cinco categorias de acordo com os processos geológico-geomorfológicos dominantes na região, sendo elas a cimeira estrutural, os planaltos, o pediplano, o pedimento e as planícies. A compartimentação da área auxiliou o entendimento dos processos ocorridos e atuantes na porção oeste do Batólito Ipojuca-Atalaia e como o regime tectônico atua como agente primário na evolução do relevo na região.

Quantifying the Geomorphology of the Drainage Basins Along the Greater Khingan Mountains in NE China

Drainage basins are fundamental elements of the earth’s surface, and quantifying their geomorphic features is essential to understand the interaction between tectonics, climatic, and surface processes. In this study, 40 basins of the Greater Khingan Mountains were selected for hypsometric analysis using a 90-m Shuttle Radar Topography Mission digital elevation model. The hypsometric integral values range from 0.13 to 0.44, with an average value of 0.30, and most hypsometric curves exhibit remarkable downward concave shapes. This feature indicates that most drainage basins and the landscape of the Greater Khingan Mountains are approaching the old-age development stage, consistent with the present moderately stable tectonic activity. The spatial distribution of the χ values is characterized by unambiguously higher values on the western flank than those on the eastern flank in the middle and southern segments of the Greater Khingan Mountains. We interpret this as an indicator of the disequilibrium across the main divide. The interpolation of the erosion rates and channel steepness for the catchments on both sides of the Greater Khingan Mountains revealed westward divide migration, which is consistent with the lower χ values, a higher slope, and local relief observed along the eastern flanks. Considering the long-term tectonic evolution pattern between the Greater Khingan Mountains and Songliao Basin, the landscape decay and slow westward divide migration were mostly driven by the inherited Cenozoic tectonics and precipitation gradient across East Asia.

Mineralization Characterization of Psammitic Rocks in Efon-Alaaye and Environs using Remote Sensing and Field Studies

This paper analyses remotely sensed data over a part of the Psammitic Rocks in Efon-Alaaye and Environs to elucidate its geology and structural framework as well as delineate the potential zones of mineralization. The study area belongs to the Precambrian Basement Complex terrain of Southwestern Nigeria and lies within the eastern unit of the Ilesha schist belt. The lithologic units comprise schistose quartzites, quartz schists, quartz-mica-schists, and granitic gneisses. Landsat 8 satellite imagery and Shuttle Radar Topography Mission imagery (SRTM), both of path 190 and row 055, were used for the purpose of this study. A total of 138 lineaments of total length of 147.948 Km, were automatically extracted from both data. Rose diagram showed that the lineaments are bi-directional, with major lineaments trending NE-SW, E-W and the subsidiary ones in the NW-SE direction. These lineaments are mostly mapped on the schistose quartzites. Also, N-S trending faults were mapped from the Digital Elevation Model map generated from the SRTM data which was confirmed to be reverse fault based on field studies. The mineral alteration map generated revealed signatures of gold, iron oxides and silica minerals, while the mineralization potential map was done with reference to established geological settings of the area in conjunction with the structural elements such as folds, faults, joints and fractures mapped and measured on the field. These structures are typical of gold mineralization and associated metallic minerals in the Ilesha schist belt. This study also confirmed that mineralization in the study area is structurally controlled and type of mineralization is epigenetic in nature as a result of favorable ground preparation.

The Response of Brewster Glacier to Five Decades of Climate

<p>Small perturbations in climate can produce measurable changes to the size of a glacier. Documenting such changes is important for quantifying water storage changes, and understanding glacier-climate interactions. By using all available geodetic data, such as Landsat imagery, Shuttle Radar Topography Mission, GNSS and photogrammetric techniques, as well as ground penetrating radar for the construction of a bed DEM, it is found that Brewster Glacier decreased in volume from 1967 to 2017, losing ∼56% of its volume, with a period of volume increase of ∼10% from 1986 to 1997. The overall pattern of geodetic mass balance is similar to the glaciological mass balance record, however, the geodetic method tends to show more negative values by an average of ∼0.6 m w.e. Contrary to many other New Zealand glaciers, which experienced an advance from 1983 to 2008, Brewster Glacier continued to retreat by 390 m during the study period, at an average rate of 7.8 m a⁻¹, but at a significantly reduced rate of ∼2 m a⁻¹ from 1997 until 2005. By comparing the records of Brewster Glacier and Fox and Franz Josef glaciers, we explore the differences in response and reaction times resulting from glacier area-altitude distribution, and climatic setting. Furthermore, DEMs produced by this study are now available for use by a New Zealand wide glacier monitoring programme.</p>

The Response of Brewster Glacier to Five Decades of Climate

<p>Small perturbations in climate can produce measurable changes to the size of a glacier. Documenting such changes is important for quantifying water storage changes, and understanding glacier-climate interactions. By using all available geodetic data, such as Landsat imagery, Shuttle Radar Topography Mission, GNSS and photogrammetric techniques, as well as ground penetrating radar for the construction of a bed DEM, it is found that Brewster Glacier decreased in volume from 1967 to 2017, losing ∼56% of its volume, with a period of volume increase of ∼10% from 1986 to 1997. The overall pattern of geodetic mass balance is similar to the glaciological mass balance record, however, the geodetic method tends to show more negative values by an average of ∼0.6 m w.e. Contrary to many other New Zealand glaciers, which experienced an advance from 1983 to 2008, Brewster Glacier continued to retreat by 390 m during the study period, at an average rate of 7.8 m a⁻¹, but at a significantly reduced rate of ∼2 m a⁻¹ from 1997 until 2005. By comparing the records of Brewster Glacier and Fox and Franz Josef glaciers, we explore the differences in response and reaction times resulting from glacier area-altitude distribution, and climatic setting. Furthermore, DEMs produced by this study are now available for use by a New Zealand wide glacier monitoring programme.</p>

Comparison of Open Source DEM’s for Morphometric Analysis of Micro Watersheds: A Case Study from the Midlands of Kerala

Morphometric analysis with the help of remote sensing and GIS is now widely used to prioritise micro watersheds for planning interventions for soil and water conservation. DEM is the main digital data used to perform the morphometric analysis. There are different types of DEMs available to perform morphometric analysis using GIS techniques. But, no authentic information is available on the degree of accuracy levels of these DEMs to quantitatively determine various morphometric parameters for the watersheds in Kerala, with typical undulating and sloping terrain features. Hence, this research has been initiated to evaluate the quality of three popular DEMs viz. SRTM(Shuttle Radar Topography Mission), CARTOSAT(Cartography and satellite) and ASTER(Advanced spaceborne thermal emission and reflection Radiometer), each with 30 m spatial resolution. Two small sub watershed of Bharathapuzha river basin have been chosen for the study which are lying near to Valanchery town in Malappuram district. More than 21 morphometric parameters including drainage network, basin geometry, basin texture and basin relief characteristics were computed using these three types of DEMs and the outputs compared with google earth map. The results shows that the SRTM 30m DEM is characterized by higher accuracy compared to CARTOSAT and ASTER and has got better matching with google earth map data sources.

An Assessment of Spatio-Temporal Characteristics of Lightning Occurrence with Elevation, a Case of Uganda

Lightning has received a lot of attention in scientific literature during the recent decade, not only because it is an impressive atmospheric phenomenon but also its associations with severe storms that cause unprecedented damages to agriculture, electric power networks, property, and life. This study assessed the Spatio-temporal characteristics of lightning occurrence with elevation in Uganda using lightning flash and elevation datasets for a period of fifteen years (1998-2013). Datasets used in this study included daily lightning flashes as captured by Lightning Imaging Sensor (LIS) aboard on Tropical Rainfall Measurement Mission (TRMM) satellite and elevation data in form of Digital Elevation Model (DEM) obtained from the Shuttle Radar Topography Mission (SRTM). Spatio-temporal results indicated that ~80% of areas with an elevation that ranges from 800-1200 m above mean sea level (masl) in Uganda had severe lightning occurrences and ~20% of areas with an elevation greater than 1200 m (masl) had severe lightning occurrences. The country received an enhanced number of lighting events with the highest number in 1999. Subsequently, a reduced trend was observed from 2002 to 2007 followed by an increment in the number of lightning events in (2010, 2011, 2012, and 2013). The intensity of the events decreased gradually though two peaks were observed, (1998-2001) and (2010-2013). Furthermore, results indicate escalations in the frequency and duration of lightning events from 60 times in 1998 to approximately 200 times in 2013 and from 1000 microseconds in 1998 to more than 2000 microseconds in 2013. Generally, the country experienced an enhanced increase in lighting occurrences over the study period which therefore calls for urgent actions to combat the root cause and also provide effective measures to reduce the impacts of lightning strikes.