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Preliminary analysis of red mud spill based on aerial imagery, Hungary
47-57Views:254One of the largest industrial spills in Europe occurred in the village of Kolontár (Hungary) on October 4, 2010. The primary objective of the hyperspectral remote sensing mission was to monitor that is necessary in order to estimate the environmental damage, the precise size of the polluted area, the rating of substance concentration in the mud, and the overall condition of the flooded district as soon as possible. The secondary objective was to provide geodetic data necessary for the high-resolution visual information from the data of an additional Lidar survey, and for the coherent modeling of the event. For quick assessment and remediation purposes, it was deemed important to estimate the thickness of the red mud, particularly the areas where it was deposited in a thick layer. The results showed that some of the existing tools can be easily modified and implemented to get the most out of the available advanced remote sensing data.
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Trend analysis of temperature over the Meghalaya Plateau: A case study of Ri Bhoi District
63-76Views:329Climate change is a reality in the present world, and most nations are fighting this menace by bringing in mitigation measures to check our carbon footprint and developing measures to make ourselves more resilient to hazards associated with climate change and global warming. These necessities measure the nature and degree of change in the climatic elements, viz., temperature, rainfall, etc. Located on the northern slopes of the Meghalaya plateau, the Ri Bhoi district is characterized by a complex climatic condition owing to its altitudinal differences. The district is divided into two distinct zones: the Highland zone, located closer to Shillong, and the Lowland zone, lying closer to the Brahmaputra plains. The economy of Ri Bhoi district is agrarian in nature, where most of the rural populations live close to nature, following subsistence agriculture with fewer technological innovations; hence, awareness of temperature changes becomes essential for carrying out their livelihoods. In this context, the present paper attempts to analyze both the minimum and maximum average monthly, seasonal, and annual temperatures over two decades (1999–2019) in both zones. The Mann-Kendall (MK) trend test and Sen’s slope estimate were employed to find the nature of the temperature trend and its magnitude in the two zones of Ri Bhoi District. The findings suggest an erratic behavior of both the maximum and minimum temperature has been observed in the Highland and Lowland zones of Ri Bhoi district over the past two decades, impacting agriculture and agro-based livelihoods.
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Monitoring temperature patterns at selected world heritage sites in Egypt using high resolution WorldClim data
42-58Views:647Long term temperature patterns helps in assessing changes in the climatic conditions of an area and climatic changes poses a major challenge to the world heritage sites whether it is natural or cultural. Therefore in this study using maximum and minimum temperature data for the period 1960-2021 downloaded from WorldClim 2.1 calculation of mean temperature is done in QGIS environment for the selected UNESCO world heritage sites of Arab Republic of Egypt. WorldClim 2.1 provides finer resolution gridded data downscaled from Climate Research Unit. Trend analysis using linear regression and Mann-Kendall method and Sen’s Slope estimate is used to understand the patterns of mean temperature at all the selected sites. The study reveals that mean temperature at all the selected sites is increasing but since 1990 the sites which are located geographically in lower Egypt are witnessing rapid increase in mean temperature compared to the sites located in upper Egypt which historically witnessed more temperature due to its geographical milieu. This study can help in stimulating the utility of geospatial data in understanding the changes in climatic parameters in relation to world heritage sites. Moreover it can serve as foundation upon which detailed longitudinal site specific investigation can be done.
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Estimating soil loss from a watershed in Western Deccan, India, using Revised Universal Soil Loss Equation
13-25Views:731USLE (Universal Soil Loss Equation) is the original and the most widely accepted soil loss estimation technique till date which has evolved from a design tool for conservation planning to a research methodology all across the globe. The equation has been revised and modified over the years and became a foundation for several new soil loss models developed all around the world. The equation has been revised as RUSLE by Renard et al. (1991) and is computed in GIS environment. The Revised equation is landuse independent which makes it a useful technique to apply in a variety of environment. The present paper is an attempt to estimate soil loss from a semi-arid watershed in Western Deccan, India by employing RUSLE. The region is a rocky terrain and sediments are restricted to only a few localities. The result indicates that the region is at the threshold of soil tolerance limit.
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Quantify the changes in landscape patterns and their impact on ecosystem services values using land use land cover data in the middle reaches of the Damodar river basin
1-15Views:119Human activities continuously modify the landscape area for their purpose which forces the landscape structure to change continuously. Therefore, it is essential to examine the impact of changing landscape structure on Ecosystem services values (ESV). The study has quantified the dynamic of ESV using land use land cover data and landscape metrics. The study has applied the Costanza et al. (1997 &2014) method to estimate ESV in the Middle reaches of the Damodar River Basin area and the Getis-Ord Gi* technique to delineate the dynamic hot spot and cold spot region in ESV within the stipulated period. The study has shown that ESV varies with the changes in landscape structure. The diminishing of vegetation, agricultural land, water body area and the expansion of built-up area has shifted the ESV zone from the North-West part in 2000-2012 to the wider part of North-West and North-East in 2012-2023 and 2000-2023 periods and marked the North-West and North-East part as a more dynamic zone within the study period.
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Human induced conservation in the natural islets. Status of vertebrate diversity in the selected sacred forests of Kerala India
41-47Views:142Sacred forests are conserved based on religious aspects. Regional differences are visible among sacred groves in their management policies, temple construction, landscapes, and religious beliefs. This study analyzed whether there is any relationship between vertebrate species diversity and the management policies adopted by respective owners. To examine this, twenty sacred groves were selected. The vertebrates, such as birds, reptiles, amphibians, and mammals were surveyed, which lasted up to 2 years. Specific methodologies, such as point count for bird survey and visual encounter surveys for other vertebrates, were followed. To analyze the management policies adopted by the respective owners, nine parameters were considered, and each parameter was given a score for all the study sites. 135 species of vertebrates were recorded, and their species diversity is estimated by using the Shannon Wiener Index. To estimate the association between the management policies and species diversity, the scores of each parameter for all the sacred groves were summed and correlated with the Shannon‒Wiener index. A positive correlation between these factors obtained indicated that the management policies taken by the owners influenced the species conservation.
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Characterization of urban aerosol sources in Debrecen, Hungary
109-119Views:163Debrecen is an average middle European city from the point of view of aerosol pollution. Its location makes the city an ideal place for observing aerosol transport processes. Systematic investigation of atmospheric aerosol of the east-Hungarian region has been performed in the Institute of Nuclear Research of the Hungarian Academy of Sciences for 20 years by accelerator based elemental analytical technique. As a complementation of this research we observed the size distribution and short-term time variation of the elemental component of fine (PM2.5) and coarse (PM10-PM2.5) urban aerosol in the frame of sampling campaigns during 2007 and 2008 in a downtown site of Debrecen. Meteorological parameters were also recorded parallel to the aerosol sampling. Elemental concentrations (Z ≥ 12) were determined by particle induced X-ray emission (PIXE) analytical technique at the Laboratory of Ion Beam Applications (IBA) of the ATOMKI. On the obtained database six sources of the urban aerosol were identified: 2 types of soil, domestic heating, sulphate originating from long range transport processes, an unidentified source enriched with chlorine and traffic. Emission episodes were also observed. The short-time variation of urban aerosol combined with meteorological data and with mass size distribution serves as a basis to reach a better understanding of the aerosol sources in receptor areas, to select local emission and long range transport episodes, to follow the evolution of aerosol, and to make a better estimate on the health impact.
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Quantitative Morphometric Analysis of Streams in Extreme Humid Areas: A Case Study of the Um-Mawiong River Basin, Mawsynram, Meghalaya
59-75Views:268Quantitative morphometric analysis of the drainage system is essential to characterising a watershed, as all the hydrologic and geomorphic processes occur within the watershed. Consequently, this plays a crucial role in understanding the geo-hydrological attributes of a drainage basin to the terrain feature and its flow patterns, thus enabling the estimate of the incidence of infiltration and runoff and other related hydrological characteristics of a watershed, which strongly impacts natural resource conservation. The study area selected is the Um-Mawiong River basin in Mawsynram, Meghalaya. The basin shows a dendritic pattern that highlights the homogeneity in the texture of the basin. Results suggest that the stream frequency of the basin is 19.10 km², suggesting a faster surface runoff and less infiltration. In addition, it has an Elongation ratio of 0.75 indicating an elongated basin shape. The current study demonstrates that the implementations of GIS techniques are trustworthy, efficient, and capable of managing extensive databases for managing river basins. The present study tries to analyse the linear, areal and relief aspects of the basin using a GIS environment and manipulated for different calculations. The analysis reveals that the total number of stream segments and length are maximum in first-order streams and decrease as stream order increases. The drainage density exhibits a high degree of positive correlation, i.e., 0.87, with its frequency suggesting an increase in stream population concerning increasing drainage density and vice versa.
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Spatial pattern of soil erosion using RUSLE model and GIS software at the Saf Saf watershed, Algeria
31-47Views:384Soil erosion is one of the problems threatening the Algerian environment. In agriculture, soil erosion leads to the thinning of the topsoil under the effect of the natural erosive forces of water, or under the effect of agricultural activities. The present study aims to estimate average soil loss rate and to identify vulnerable zones. Through the integration of RUSLE model at the Saf Saf watershed, various parameters are utilized such as the rainfall erosivity factor (R), soil erodibility factor (K), slope length - slope factor (LS), crop management factor (C) and practice management factor (P). All these parameters are prepared and processed through a geographic information system (GIS) and remote sensing using various database sources. The results reveal that the river basin has an average annual soil loss of 3.9 t ha−1 yr−1, and annual soil loss of 4.53 million tonnes for the period 1975-2017. Meanwhile, eighty five percent of the study area is experiencing acceptable rate of soil erosion loss, which is ranging between 0 to 5 t ha−1 yr−1. The present study of risk assessment can contribute to understand the spatial pattern of soil erosion in order to use appropriate conservation practices for sustainable soil management.
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Above ground forest biomass distribution in the landscape of Jorhat, Assam, India
16-31Views:10This study aims to analyze the spatial and temporal variations in above-ground biomass (AGB) within the Jorhat region from 2001 to 2023. It also highlights the impacts of urbanization, physiographic characteristics, and soil types on AGB variation. In order to accurately assess landscape-level variation of biomass, a combination of field surveys, remote sensing techniques, and modelling approaches are employed in this study. Biomass estimation is difficult over large area using traditional method. The synoptic nature of satellite-based data improves the monitoring of inaccessible areas. Results show approximately 16.6% decrease in AGB, with urban and peripheral areas experiencing the most notable declines due to reduced forest cover. Physiographic analysis reveals low AGB values in marshes (13 t/ha), swamps (14 t/ha), and char lands (25 t/ha). The growth of trees is suppressed seasonal flooding in this physiography. Additionally, AGB follows an increasing trend from North to South, in alignment with the region’s elevation profile. Soils also exhibit variations in AGB, with alluvial soils supporting higher biomass compared to other soil types. Key ecological linkages and spatial patterns are highlighted in this study, laying the groundwork for more proactive and comprehensive environmental management. Finally, in a time of fast environmental change, these insights can assist stakeholders and policymakers
in creating more evidence-based, flexible solutions to protect ecosystems.