Environmental Earth Sciences最新文献

Virtual reality (VR) is an emerging platform that has the potential to advance techniques in geological fieldwork. However, geologists currently lack the variation of necessary VR toolsets for this purpose. The reason is that VR is still relatively new and developing as a technology. This is the reason most VR research relating to geoscience have been relatively limited and niche, with a predominant focus on more social-related studies. Therefore, this paper aims to showcase an alternate application approach of VR by conducting a geological investigation and interpretation of a small landslide in Hokkaido, developed following the 2018 Hokkaido Eastern Iburi Earthquake. To accomplish this task, a virtual replica of the landslide was reconstructed in VR using close-range remote sensing techniques with uncrewed aerial systems, along with accompanying VR measuring tools. We discuss the influence of the pre-earthquake topography on the landslide’s current morphology and sediment deposition patterns from the VR-based topographical measurement results. Furthermore, this study also provides some insight into smaller landslide types which are typically overlooked in current research works. It is recommended that future research further explore VR fieldwork applications across different geomorphological subjects. This research offers valuable insights for practitioners interested in adopting VR technology, while also enhances the current understanding of the landslide phenomenon through a VR-based perspective.

This study, focusing on landscape patterns, established a spatial conflict metric model to recognize the temporal and spatial evolution of conflict intensity in urban agglomeration. It further evaluated the value of ecosystem services through the equivalent factor method. Utilizing spatial autocorrelation, the study area was zoned, and tailored development recommendations were proposed based on the characteristics of each zone. The results show that: (1) The spatial conflict intensity of the urban agglomeration around Poyang Lake shows an upward trend and obvious spatial differentiation. Specifically, the low-conflict zones mainly concentrated in the western and eastern mountainous areas of the study area with block distribution, while the high-conflict zones are dispersed in the urban core area. (2) Between 1990 and 2020, the ecosystem service value of the study area showed an increasing trend, with woodland contributing the most. Western, northeastern, and southeastern regions boast high service values, contrasting with the low values in the metropolitan agglomeration and its periphery. (3) A negative spatial correlation was observed between spatial conflicts and ecosystem service values, with the correlation gradually intensifying from 1990 to 2020.

Ramsar sites across the world are vulnerable to pollution and degradation despite their special status and conservation measures. This study was conducted on the Ghodaghodi Lake of Nepal – a Ramsar Site to assess the seasonal variation of water quality and to detect pollution, if any. Water samples were collected in the pre-monsoon and post-monsoon periods from different parts of the lake. Of the various water quality parameters, temperature, pH, EC, TDS, DO levels were measured in-situ, while concentration of Ca²⁺, Mg²⁺, K⁺, Na⁺, Cl^ˉ, SO₄^2˗, NO₃^ˉ, HCO₃^ˉ, NH₄⁺, and PO₄³⁻ ions was analysed in laboratory. Water of the lake is found to be slightly alkaline with mean pH 7.88 and 8.22, in the pre-monsoon and post-monsoon, respectively. In terms of abundance, the major ions follow the order of Ca²⁺ > Mg²⁺ > Na⁺ > K⁺ for cations and HCO₃^ˉ > Cl^ˉ > NO₃⁻ > SO₄^2˗ > PO₄³⁻ for anions. Mean concentrations of Ca²⁺ are 17.87 and 19.58 mg/L, and of HCO₃ˉ are 42.14 and 186.2 mg/L, respectively in the two seasons. Statistical tests such as correlation analysis, cluster analysis, and principal component analysis (PCA) and the Piper, Gibbs, and Mixing plots were used further to understand the nature, origin, and geochemical evolution of the lake water. Carbonate-rock weathering is found to be the chief controller of the lake-water chemistry, while anthropogenic activities emerged as the main reason for organic pollution in the lake as is reflected in the low (< 5.0) dissolved oxygen (DO) level. However, comparison with the WHO guidelines and the Water Quality Index (WQI) values (0–25) certify that water of the lake is absolutely safe for drinking and irrigation.

Commonly encountered problems, such as insufficient bearing capacity of the foundation and significant soil deformation, typically necessitate improvements to sandy soil. The excessive use of traditional soil improvement materials, such as cement and lime, causes irreversible damage to the ecological environment. As a sustainable soil reinforcement material, xanthan gum has broad application prospects with respect to its effects on the bearing capacity and deformation of sandy soil foundations. In this study, scanning electron microscope tests and cone penetration model tests based on particle image velocimetry technology were conducted to investigate the microstructure, mechanical behavior, and deformation characteristics around cones in sand treated with different xanthan gum rates. The test results show that the xanthan gum exerts cementation and filling effects between sand particles, enhanced the bearing capacity of sand. The displacement field around the cones in xanthan gum–treated sand during the penetration exhibits good symmetry. With increasing xanthan gum rate, the maximum displacement value and vertical influence range around the cone of xanthan gum-treated sand decrease, while the horizontal influence range increases. On the basis of the cone penetration test result, a predictive model for the vertical bearing capacity incorporating the xanthan gum rate is proposed using the Laboratoire Central des Ponts et Chaussées (LCPC) model. The research results can provide a scientific basis for using xanthan gum when designing and constructing sandy soil foundations.

This paper presents a comprehensive study on the use of Electrical Resistivity Imaging (ERI) for non-invasive monitoring of the root zone, focusing on an infiltration experiment with a lemon tree in a controlled outdoor environment in Dhahran, Saudi Arabia. Over seven months, the study employed 3D and 4D ERI methods to capture root activity and distribution under realistic weather, soil, and water conditions. Findings include the detection of a resistive anomaly in the root zone extending to 50 cm depth, influenced by high summer temperatures which distorted resistivity signatures. Heterogeneous water infiltration was evident, with lateral resistivity variations and preferential flow paths during irrigation. Ground-truthing validated the root zone’s geometry, confirming the imaging results. The study underscores ERI’s potential for precision agriculture. This innovative approach underscores the potential of 3D and 4D ERI methods in enhancing precision agriculture and environmental management practices.

A large Geologic Carbon Sequestration (GCS) hub has been proposed in Kemper County, Mississippi. The target injection interval consists of numerous Cretaceous-aged deep saline aquifers overlain by a competent and extensive regional sealing layer. Above the seal, the deepest Underground Source of Drinking Water (USDW) at the site is the Eutaw aquifer of the Eutaw Group and McShan Formation, undifferentiated. To assess potential risks of leakage from the deep sequestration reservoir, a model of a portion of the Cretaceous Eutaw Group was constructed in this study. Simulations tested various permeabilities, hypothetical leakage rates, and plume mitigation strategies utilizing existing wells. Results suggest that, under the influence of regional groundwater flow fields, leaking CO₂ would effectively bypass the existing wells, and to influence this migration would require very large water extraction rates. Therefore, to ensure plume detection, monitoring for leakage at the injection wells themselves is very important.

Climate change has significantly impacted rainfall patterns, water availability, and security. Changes in rainfall alter the groundwater table, primarily sourced from rainfall in tropical regions, a crucial source of freshwater on Earth. Assessing its potentiality, quality, and replenishment feasibility continues to pose a challenge. Our study aims to identify potential groundwater zones to define artificial recharge zones by considering hydrogeological aspects and water quality. Additionally, the study aims to propose suitable recharge structures for different lithological groups in Kangsabati Upper Catchment. The present study used the extreme gradient boosting (XGBoost) algorithm and analytical hierarchy process (AHP) model to delineate the groundwater potential zones and suitable zones to replenish the water table. The XGBoost model evaluated the groundwater potential zones with 81% accuracy (SVM > RF > ANN) and identified various levels of potential. The area with very high and high prospects covers 23.36% and 20.14% respectively, while 20.32% and 13.94% of the area is covered by the low and very low prospect zones. On the other hand, according to the AHP approach, the estimated percentage of coverage for the classes is as follows: very good (< 1%), good (21.45%), moderate (57.53%), poor (15.63%), and unsuitable (5.21%). The study unveils that the east-central, east, north and the area within 300 m contour lines are ideal for both groundwater potential and replenishing the water tables. To achieve the objectives of Sustainable Development Goal (SDG) 6, effective strategies for suitable utilization and artificial recharge of water resources may result from implementing Machine Learning-Multiple Criteria Decision Making (ML-MCDM) models with pertinent influencing factors.

Settlements have been exposed to various disasters depending on their location and characteristics. One of these disasters is flooding, which affects the most widespread areas globally and causes significant economic loss. Numerous studies have been conducted at various scales, and different methods have been used to understand and mitigate the effects of floods. None of these studies conducted flood susceptibility analyses for settlement basins on a provincial scale using parameters derived from inventory basins. This study aims to determine the flood susceptibility of the settlements and their basins located along riversides and valley floors at the provincial scale based on the predominant morphometric characteristics of settlement basins that have previously experienced floods. For this purpose, a flood susceptibility analysis was conducted on 483 basins of 344 settlements located along riversides and valley floor morphologies out of 735 settlements in the province of Bursa (Türkiye). Among the morphometric and surface parameters frequently used in the literature, the nine parameters identified as having the highest impact for the 28 settlement basins in the training set—the bifurcation ratio (({text{R}}_{text{b}})), drainage density (({text{D}}_{text{d}})), time of concentration (({text{T}}_{text{c}})), slope, topographic wetness index (TWI), stream power index (SPI), precipitation, hydrological soil groups (HSG), and lithology were applied to the other settlement basins. The results were validated with data from 22 settlement basins where flooding occurs, and maximum consistency was found. In the flood susceptibility analysis, the Normalised Morphometric Flood Index (NMFI) was used to evaluate each and overall parameters collectively. As a result, 51% of the settlements in Bursa province were identified as having high flood potential. This finding also reveals the prioritising of flood studies in three districts of Bursa province. This study identifies which settlements within the provincial border are susceptible to flooding and provides critical insights into which districts should be prioritised for flood risk management.