Potential Spatial Distribution Research Articles

Cluster Mapping of Waste Exposure Using DBSCAN Approach: Study of Spatial Patterns and Potential Distribution in Bantul Regency

High level of plastic waste production is a common issue in various places, including the Special Region of Yogyakarta province. It is proven that the Piyungan Integrated Waste Disposal Site (TPST) or Final Disposal Site (TPA) in Bantul Regency has been closed several times due to capacity exceeding the quota and some blockages from residents around the TPA. Issues related to microplastic contamination resulting from discarded plastic waste are fascinating to study, considering the long-term impact of microplastic contamination on human health. This research aims to map the distribution of locations with the potential for waste accumulation to reduce the negative consequences of microplastic contamination. The population used included TPS and markets in Bantul District, with the sample being the distribution of TPS and market points in Bantul District in 2023. The results of checking the point distribution pattern using the quadrant and nearest neighbor method showed that the distribution of waste accumulation points had a clustered design; thus, it could be continued with cluster analysis using the Density-Based Spatial Clustering of Applications with Noise (DBSCAN) method. Meanwhile, the number of clusters was determined iteratively from a combination of DBSCAN parameters (MinPts and Epsilon). The best method was evaluated based on the Silhouette Coefficient (SC) value, which in this case was 0.78 (MinPts 7 and Eps 1500) and included in the strong category. Subsequently, exploration was carried out by reducing the MinPts value and the lowest limit value of strong SC.

Soil water potential measurement using fiber-optic sensing technique

Accurate measurement of soil water potential or suction is crucial for hydrology and geotechnical engineering. Inspired by recent advances in fiber-optic sensing techniques, we develop an innovative geophysical method for measuring the soil suction by using fiber Bragg grating (FBG), named FBG-suction method. In this study, working principles and theoretical background associated with the FBG-suction method are discussed. For verification purposes, a series of laboratory-scale tests including calibration, suction measurement, and evaporation monitoring are performed on two clayey soils of low to high plasticity under different degrees of saturation. The calibration and measurement results demonstrate the efficacy and accuracy of the developed method for measuring a wide range of soil suction. The curves of soil saturation with suction obtained by WP4C and FBG-suction method are comparable and reflect the difference in the water retention capacity of the tested soils. Additionally, the evaporation monitoring results show that the FBG-suction method can measure the low suction during the drying process and accurately obtain the high suction above the measuring range of the PST-55 psychrometer. The findings affirm the scientific viability of the fiber-optic sensing technique for acquiring the spatial distribution of water potential or suction in unsaturated soils and provide a novel perspective for future investigations into the spatiotemporal evolution characteristics of in-situ unsaturated soil under climate change. As interdisciplinary collaborations continue to advance, it becomes increasingly apparent that methods based on fiber-optic sensing have the potential to revolutionize traditional approaches to characterizing dynamic subsurface processes.

Seasonal effects on the potential spatial distribution of Amazonian migratory catfishes

Seasonal effects on the potential spatial distribution of Amazonian migratory catfishes

Influence of environmental factors on habitat of <em>Jasminum subtriplinerve</em> in Central Vietnam

Jasminum subtriplinerve, a rare and valuable medicinal plant, is facing the problem of habitat loss. This study was conducted to determine the influences of environmental factors on the distribution and identify habitat suitability areas for this species in Central Vietnam. Based on the 19 bioclimatic, 10 soil properties, 3 topographic variables and 86 observed locations, we used Correlation Analysis processing, follow by the Maximum entropy (MaxEnt) algorithm was applied to predict the spatial potential distribution of J. subtriplinerve. Using the MaxEnt model for analyzing the J. subtriplinerve distribution showed a good performance (AUC testing = 0.821 and AUC training = 0.887). The most influential factors on J. subtriplinerve distribution were Altitude (49.2%), Mean diurnal range (10.6%), Isothermality (6.9%), Bulk density (5.2%), Normalized difference vegetation index (4.7%) and Proportion of sand particles (4.6%). In addition, the model showed that very high and high potential habitat areas of J. subtriplinerve occupied 3.17% (658.88 km2) and 8.95% (1,858.56 km2) of the studied site, distributed in the midland and low mountainous areas, the most suitable Altitude ranged from 8.1 to 138.7 m. Meanwhile, 15.17%, 18.10% and 54.60% of the studied site were nominated as moderate (3,148.93 km2) low (3,758.10 km2), and very low (11,334.17 km2) potential habitat areas, respectively. This study comprehensively evaluated factors affecting habitat suitability, therefore, these results provide an understanding of the bioecological distribution of J. subtriplinerve guiding the identification of optimal areas for cultivation and conservation.

On the specific behavior of the work function and surface potential of an asymmetric metal-dielectric nanosandwich

We examine thin film on a dielectric substrate (vacuum/Al/SiO2) in the stabilized jellium model and the Kohn–Sham method. We investigate surface and size effects on the effective potential and the electron work function, and analyze the spatial distributions of electrons and potentials. It is found that a dielectric environment generally leads to a decrease in the work function. The effect of dielectric confinement for the electron work function of the asymmetric metal-dielectric nanosandwiches is reduced only by the surface area weighted average value of the dielectric constants. This conclusion follows from the application of the Gauss theorem for a conducting sphere with an inhomogeneous dielectric coating. The flow of electrons from the dielectric face to the vacuum one due to the contact potential difference manifests itself in the appearance of an additional dipole between the left and right face within the spatial distributions of ions. This leads to the fact that in a vacuum the electrostatic and effective potentials change sign twice, as a result of which a potential barrier appears above the vacuum level. We introduced the position of an electron conduction band in the dielectric as the input parameter in the self-consistency procedure for one of the sandwich approximations. As it turned out, the barrier height depends only on the used local or non-local approximation of the exchange-correlation energy. The nontrivial origin and behavior of the calculated effective potential on the vacuum side of the film, as well as the reasons for it, are discussed.

Mapping the potential spatial distribution for offshore finfish aquaculture in China under climate change

Offshore aquaculture plays an important role in alleviating the pressure of coastal aquaculture and promoting the sustainable development of fisheries. And changes in ocean conditions caused by climate change will have a huge impact on mariculture. Considering the conditions of climate change, this study took the main mariculture fishes in China as the research object, used a species distribution model (SDM) to predict the potential mariculture areas of each fish under the current and different future (2040–2050) climate scenarios, divided the mariculture areas into three potential levels by natural breaks classification method, and calculated the area of different levels potential areas of each fish through the grid number and grid unit area. Additionally, this paper compares the potential area variation of different fishes under different climate scenarios. The results indicate that: (1)In the current climate, the potential area of Yellowtail kingfish(Seriola lalandi) is the largest among seven fishes, estimated at 1,288,500 km2. And the number of varieties suitable for aquaculture in the East China Sea and the South China Sea is more than that in the Bohai and Yellow Seas. (2)Compared with the high potential area of current and future climate scenarios, Large yellow croaker(Larimichthys crocea) has the largest increase, Yellowtail kingfish(Seriola lalandi) decreases under all four future climate scenarios, and both Cobia(Rachycentron canadum) and Allied Kingfish(Seriola dumerili) has small changes. (3)In the future climate scenarios, the number of species potentially suitable for culturing increases significantly in the Bohai and Yellow Sea area, and in the South China Sea, the suitable areas for cultured Large yellow croaker(Larimichthys crocea), gold pompanos(Trachinotus ovatus), Cobia(Rachycentron canadum) and Allied Kingfish(Seriola dumerili) decrease significantly. Overall, the potential areas of each fish show a northward trend.

An integrated ecosystem service-based approach for the sustainable management of forested islands in South Korea

Implementing sustainable island forest management policies requires categorizing the islands into groups based on key indicators and establishing a consistent management system. This study proposes a novel framework to support an ecosystem service-based approach to managing forested islands in South Korea. First, a typology of six forested island categories is established based on varying extents of natural vegetation cover (as a percentage of forest cover) and connectivity to the mainland. An analytic hierarchy process (AHP) analysis was conducted with island forest experts to identify priority ecosystem services (ESs) for the sustainable management of each island type. On connected islands, provisioning services (natural resources and natural medicines) are more important than regulatory (erosion control) or supporting services (genetic diversity). On unconnected islands, particularly those with a small proportion of natural vegetation, regulatory services (erosion control) require a greater emphasis on management. Since Type 3 islands require urgent management as connectivity to the mainland makes natural vegetation=sparse island forest ecosystems vulnerable to anthropogenic activities, the land-use scoring method was performed on Jin-do. Comparisons between the AHP-derived expert demand for key island ESs and the spatial distribution of ES supply potential revealed mismatches between supply and demand for erosion control, freshwater supply and habitat provision. The framework developed in this study can help guide policy and decision-making processes and indicate where interventions should be focused to achieve sustainable island management.

Potential Regeneration and Spatial Distribution model of Saurauia pendula Blume in Mount Slamet, Central Java

Saurauia pendula Blume is a species of genus Saurauia and belong to Actinidiaceae family. Saurauia pendula spread over on several highlands or mountains in Java Island. Mount Slamet is the second highest mountain on Java with naturally good vegetations. The existence of several threats such as forest fires, destruction, deforestation and forest degradation has caused the condition of these plant species to begin to require attention. This study aims to determine the population of S. pendula, its potential regeneration and spatial distribution model in Mount Slamet area. The study was conducted on four (north, south, west and east) slopes in 2019-2020. Research on population conditions was carried out by following hiking trails and making new paths around the center of suitable habitat. Coordinate data is taken to make spatial analysis using Maximum Entropy (MaxEnt). The results showed that the number of S. pendula was found on the north, west and south slopes at an altitude of 1010-2024 masl. This species has a significant association with Saurauia microphylla de Vriese., Glochidion obscurum (Roxb. ex Willd.) Blume and Castanopsis argentea. The number of mature plants is 106 individuals, which have important role in the distribution of this plant. Analysis of the spatial distribution model shows that S. pendula is estimated to be widely distributed on the western slopes of Mount Slamet.

Potential spatial distributions of Tibetan antelope and protected areas on the Qinghai-Tibetan Plateau, China

Potential spatial distributions of Tibetan antelope and protected areas on the Qinghai-Tibetan Plateau, China

Characterizing longshore transport potential and divergence of drift to inform beach loss trends

Beach loss is a growing global challenge that threatens the safety of coastal communities, the health of coastal ecosystems, recreational amenities, and regional economies dependent on tourism. Spatial gradients in longshore sediment transport, or divergence of drift (DoD), is a primary driver of beach width change over multi-annual time scales, but the response of any particular beach can be challenging to characterize and predict. Here we present a new method to characterize DoD using a non-uniform segmentation of the coastline informed by the spatial distribution of longshore transport potential, including the location of physical barriers identified using satellite imagery, and both maxima and reversals in longshore transport potential derived from nearshore wave data. The method demonstrates improved capacity to predict beach width trends at sandy beaches compared to methods that rely on a uniform segmentation of the coastline. In an application to southern California where satellite data documents two decades of beach width change, the non-uniform segmentation method correctly predicts the sign of beach trends at 93% of transects within a littoral cell and achieves a linear correlation between DoD and beach width trends exceeding 0.8. Moreover, we find that a minimum of five years of data are required to establish consistently strong correlations between DoD and beach width changes. Conversely, use of a uniform segmentation is shown to be unreliable for estimating beach width trends due to strong sensitivities to shoreline segment size. This work shows the potential to leverage nearshore wave data and satellite-based beach width data for improved characterization of shoreline dynamics relevant to beach erosion management.

Investigation on Ion extraction processes in M-Type electrode configuration and the influence of top electrode

In the realm of ion extraction from photoplasma, the design of electrode configuration exerts a significant influence over-extraction efficiency by tailoring the vacuum gap and electric potential distribution. Over time, various electrode configurations have been explored, including parallel-plate, wire-type, M-type, and Π-type designs. Notably, the M-type configuration has shorter ion extraction times. In the present study, a comprehensive investigation of the ion extraction process with the M-Type setup is performed using a 2D2v-electrostatic Particle-in-Cell simulation. The study focuses on the spatiotemporal evolution of photoplasma, the formation of the plasma sheath, and the spatial distribution of electric potential. Subsequently, a series of computational experiments have been conducted by systematically altering the size of the top electrode in the M-type configuration, effectively transforming it into wire-type and Π-type. The objective of these experiments is to explore the impact of the top electrode on ion extraction. The obtained simulation results report a significant finding: the formation of a virtual anode between the cathodes. This distinct phenomenon substantially contributes to an exceptional level of efficiency, exceeding 90%, among different simulated configurations. Furthermore, it also reports an approximate 95% collection efficiency with minimum collection time with an M-type configuration over the Π-type electrode configuration.

Graphene & its applications as field effect transistors

Graphene, owing to its excellent physical, mechanical, and electrical properties, as well as its outstanding optoelectronic properties, has garnered significant attention. Consequently, it has opened numerous opportunities for various types of future devices and systems. Graphene, a one-atom-thick layer of carbon atoms forming a honeycomb 2D crystal lattice, stands out as one of the most promising candidates in the field of nano- and microelectronics. This review provides an introduction to graphene, detailing its properties and its applications, particularly focusing on its utilization in the realm of Field Effect Transistors (FETs). Specifically, an analytical device model of heterostructure-based FETs is presented, which essentially comprises an array of nano ribbons clad. The model for Graphene Nano Ribbon (GNR) FETs includes Poisson's equation and can be employed to calculate the current-voltage characteristics and spatial distribution of electric potential along the channel.

Response of vegetation carbon sequestration potential to the effectiveness of vegetation restoration in karst ecologically fragile areas in Guizhou, southwest China

In the southwest karst areas of China, changes in overlying vegetation due to ecological restoration cause considerable carbon sequestration (CS). Assessing the CS potential of vegetation restoration in this areas is crucial for promoting the optimization and regulation of regional vegetation restoration(VR) policies. This study is based on net primary productivity, maximum vegetation coverage and average vegetation coverage. Using the VR effectiveness index (Ej) to quantitatively evaluate the spatiotemporal characteristics of VR effectiveness, quantifying the spatiotemporal pattern of vegetation restoration CS using the vegetation photosynthetic CS model, and clarifying the main driving mechanisms of vegetation restoration CS.This results showed that more than 54.25 % of the studied area in the ecologically fragile areas has achieved significant VR (Ej ≥ 20) from 2000 to 2020. The spatial distribution of vegetation CS intensity and potential was higher in the southwest than in the northeast. Moreover, there was a strong spatial correlation between the areas with greater vegetation CS densities and the areas with poor natural background conditions, showing that the effectiveness of ecological restoration and economic growth complement each other. The correlation between the potential for vegetation CS and the current value of vegetation cover was r = 0.06 (p < 0.05) and the correlation with the magnitude of change in vegetation cover was r = 0.38 (p < 0.05), which indicates that vegetation CS has a greater potential where the magnitude of vegetation greening is greater. The greening range of vegetation was constrained by the natural background environment in ecologically fragile areas, and the continuous enhancement of positive feedback intervention and weakening of negative feedback tended to promote the greening range of vegetation on the ground surface and increased the CS potential. This results provide a reference for the long-term goal of “carbon neutrality” in response to VR and CS in ecologically fragile areas to offset atmospheric CO2 emissions.

Delineation of groundwater potential zone using remote sensing and GIS-based AHP for sustainable groundwater management in Aceh Besar Regency, Aceh Province, Indonesia

Sustainable groundwater management is crucial for ensuring the long-term availability of water resources and supporting socio-economic activities. As water demands increase and hydrological systems become more complex, accurately identifying groundwater potential zones is essential for effective resource planning and utilization. However, the in-situ data availability is often very limited, particularly on a regional scale. To solve this problem, this study aimed to delineate groundwater potential zones in Aceh Besar Regency using remote sensing and a GIS-based AHP (analytical hierarchy process). Several factors were used to determine groundwater potential zones, including lithology, land use/land cover, slope, lineament density, drainage density, rainfall, and soil type. Each factor was weighted based on an extensive literature review and knowledge-driven decision-making techniques. The results indicated that 26.35% of the area was classified as having low groundwater potential, whereas 53.86% was classified as moderate. Areas that have high to very high groundwater potential cover 16.76% to 3.04% of the Aceh Besar territory. The high groundwater potential zones were mostly located in alluvial and clastic sediments lithology, gentle slopes, and had high annual rainfall. Meanwhile, areas with igneous and metamorphic lithology as well as steep slopes, had moderate to low groundwater potential. Validation was carried out by collecting the high-yield existing production wells and calculating the area under the curve (AUC) of the receiver operating characteristic (ROC) curve with relatively good accuracy (74.5%). This research has effectively described the spatial distribution of groundwater potential, contributing to sustainable groundwater management and enabling informed decision-making for sustainable groundwater practices.

Modeling and Mapping of Groundwater Potential Zones of the Shewasoor Sub-Basin Using Analytical Hierarchy Process, RS and GIS Techniques in Kirkuk, Northeastern Iraq

Groundwater is considered one of the most vital natural resources for sustaining life. The demand for water in the Shewasoor sub-basin is constantly increasing due to formidable population growth and the development of human activities. Besides, groundwater is scarce due to climatic changes in arid and semi-arid. This study aims to determine spatial distribution of groundwater potential in the Shewasoor sub-basin. This study relied on seven layers (geology, slope, elevation, lineament, drainage density, soil, and land use/land covers) using geographic information systems, remote sensing, and applying the analytical hierarchy process method after determining the weights for each parameter by a multi-criteria decision analysis; to model the groundwater potential map in the Shewasoor sub-basin. The result appeared as a map of groundwater potential categorized into five zones. The majority of the sub-basin (61.8 km2) falls under a very high-high groundwater potential zone, which distributes over an area of elevations, drainage density, and slopes low of the Bai-Hassan Formation; from the center towards the north of the sub-basin. The moderate groundwater potential zone (47.6 km2) mainly encompasses an area of elevations and slopes moderate to the Bai-Hassan formation. About 49.6 km2 is a very low to low groundwater potential zone, mainly found over the area of the elevations and slopes high within the Mukdadiyah Formation east of the sub-basin; in addition to, low groundwater potential within the Bai-Hassan Formation in the south, west, and some part center of the sub-basin due of the elevations and slopes high.

Groundwater potential delineation using geodetector based convolutional neural network in the Gunabay watershed of Ethiopia

Groundwater potential delineation is essential for efficient water resource utilization and long-term development. The scarcity of potable and irrigation water has become a critical issue due to natural and anthropogenic activities in meeting the demands of human survival and productivity. With these constraints, groundwater resource is now being used extensively in Ethiopia. Therefore, an innovative convolutional neural network (CNN) is successfully applied in the Gunabay watershed to delineate groundwater potential based on the selected major influencing factors. Groundwater recharge, lithology, drainage density, lineament density, transmissivity, and geomorphology were selected as major influencing factors during the groundwater potential of the study area. For dataset training, 70% of samples were selected and 30% were used for serving out of the total 128 samples. The spatial distribution of groundwater potential has been classified into five groups: very low (10.72%), low (25.67%), moderate (31.62%), high (19.93%), and very high (12.06%). The area obtains high rainfall but has a very low amount of recharge due to lack of proper soil and water conservation structures. The major outcome of the study showed that moderate and low potential is dominant. Geodetoctor results revealed that the magnitude influences on groundwater potential have been ranked as transmissivity (0.48), recharge (0.26), lineament density (0.26), lithology (0.13), drainage density (0.12), and geomorphology (0.06). The model results showed that using a convolutional neural network (CNN), groundwater potentiality can be delineated with higher predictive capability and accuracy. CNN based AUC validation platform showed that, 81.58% and 86.84% were accrued from the accuracy of training and testing values, respectively. Based on the findings, the local government can receive technical assistance for groundwater exploration, and sustainable water resource development in the Gunabay watershed. Finally, the use of a detector-based deep learning algorithm can provide a new platform for industrial sectors, groundwater experts, scholars, and decision-makers.

Evaluation Method for Hosting Capacity of Rooftop Photovoltaic Considering Photovoltaic Potential in Distribution System

Regarding the existing evaluation methods for photovoltaic (PV) hosting capacity in the distribution system that do not consider the spatial distribution of rooftop photovoltaic potential and are difficult to apply on the actual large-scale distribution systems, this paper proposes a PV hosting capacity evaluation method based on the improved PSPNet, grid multi-source data, and the CRITIC method. Firstly, an improved PSPNet is used to efficiently abstract the rooftop in satellite map images and then estimate the rooftop PV potential of each distribution substation supply area. Considering the safety, economy, and flexibility of distribution system operation, we establish a multi-level PV hosting capacity evaluation system. Finally, based on the rooftop PV potential estimation of each distribution substation supply area, we combine the multi-source data of the grid digitalization system to carry out security verification and indicator calculation and convert the indicator calculation results of each scenario into a comprehensive score through the CRITIC method. We estimate the rooftop photovoltaic potential and evaluate the PV hosting capacity of an actual 10 kV distribution system in Shantou, China. The results show that the improved PSPNet solves the hole problem of the original model and obtains a close-to-realistic rooftop photovoltaic potential estimation value. In addition, the proposed method considering the photovoltaic potential in this paper can more accurately evaluate the rooftop PV hosting capacity of the distribution system compared with the traditional method, which provides data support for the power grid corporation to formulate a reasonable PV development and hosting capacity enhancement program.

Optimization of NiFe oxygen evolution reaction catalytic electrode based on characterization of onset potential distribution

Lower onset potential and uniform distribution of catalytic performance are crucial for catalytic electrodes. This study presents a method for characterizing the spatial distribution of the initial potential on the surface of the oxygen evolution reaction (OER) catalytic electrode using total internal reflection imaging (TIRi). By applying linear sweep voltammetry (LSV) with incremental positive potential to the electrode, the surface of the electrode generates micro-to-nanometer-sized O2 bubbles during the initial phase of OER, resulting in an increase in light intensity and a decrease in the effective refractive index (RI). By establishing the relationship between light intensity and potential, the spatial distribution of the OER onset potential can be quantified, enabling direct visualization of the electrode's surface and its catalytic activity. Furthermore, we applied the TIRi method to assess the influence of different substrates and electrodeposition conditions on the catalytic activity, repeatability, and durability of NiFe catalytic electrodes. This research contributes to the evaluation of various electrode deposition methods for large-scale catalytic electrodes and the rational manufacturing of efficient OER electrodes in industrial energy devices, promoting the development of the hydrogen energy field.

Ferroelectric Domain Wall p-n Junctions.

We have used high-voltage Kelvin probe force microscopy to map the spatial distribution of electrical potential, dropped along curved current-carrying conducting domain walls, in x-cut single-crystal ferroelectric lithium niobate thin films. We find that in-operando potential profiles and extracted electric fields, associated with p-n junctions contained within the walls, can be fully rationalized through expected variations in wall resistivity alone. There is no need to invoke additional physics (carrier depletion zones and space-charge fields) normally associated with extrinsically doped semiconductor p-n junctions. Indeed, we argue that this should not even be expected, as inherent Fermi level differences between p and n regions, at the core of conventional p-n junction behavior, cannot occur in domain walls that are surrounded by a common matrix. This is important for domain-wall nanoelectronics, as such in-wall junctions will neither act as diodes nor facilitate transistors in the same way as extrinsic semiconducting systems do.

Identifying priority wetlands for the conservation of waterbirds in Wuhan, China

Given the severe threats affecting waterbirds and the limited resources, it is crucial to identify priority wetlands to optimize conservation efforts for waterbirds. This study aims to prioritize wetlands in Wuhan City based on the diversity, rarity, and conservation costs of waterbirds. Firstly, 17 focal waterbird species were selected as conservation targets based on the data availability and species rarity. The MaxEnt model was used to simulate the potential spatial distributions of the focal waterbirds, and corresponding weights were assigned based on their conservation status. Secondly, the Human Footprint Index (HFI) was employed to represent conservation costs. Finally, the Zonation 5 spatial prioritization software was used to identify cost-effective priority wetlands for waterbird conservation. The results show: (1) The species distribution model indicated that the distance to the wetland, land cover, and distance to the road were the primary environmental variables influencing the potential spatial distribution of focal waterbirds. (2) The top 10 %, top 20 %, and top 30 % priority wetlands identified by Zonation 5 had average coverage rates of 15.2 %, 28.0 %, and 39.6 % for focal waterbirds, respectively. (3) We identified major wetland conservation gaps in Wuhan, primarily including Caohu Lake, Luhu Lake, Futo Lake, and parts of Liangzi Lake. (4) Additionally, we recommend enhancing waterbird management in existing wetland protected areas, such as the Hougong Wetland Park and Donghu Wetland Park, to improve the effectiveness of waterbird conservation efforts. Our research provides scientific evidence to support the conservation of wetlands in Wuhan and the promotion of waterbird diversity. It also emphasizes the importance of finding a balance between conservation effectiveness and cost.