Settlement Change Research Articles

Analysis of natural and man-made factors of landslide development in the Carpathian region using GIS

Purpose. Determination of the dependencies of spatial relationships between landslides in the Carpathian region of Ukraine and the factors causing them, taking into account the differences in geomorphological, geological, climatic conditions and natural and geographical zoning according to the landscape principle. Methodology. The morphometric analysis of the territory was carried out using QGIS tools to determine the slope angles and exposure; linear characteristics were calculated: distances to the river, road, and houses. Based on the image interpretation data, we calculated the total annual rainfall and average annual air temperature. The impact of the factors considered on landslide formation was assessed using multivariate statistical analysis: factor analysis and linear multiple regression. Findings. Studies on the impact of natural and topographical conditions and anthropogenic activity on the development of landslide processes have been conducted. Orographic and climatic factors play the most important role. Construction of business facilities results in a decrease in the slope stability in 14–19 % of cases. The analysed independed factors showed good consistency between the distribution of existing landslides and the parameters under consideration: the share of the total variance of the factors under consideration is 71–76 %, the coefficient of determination of the regression model is 0.7. Based on the results of geoinformation and statistical analyses, it is proved that differences in geomorphological conditions and human activity (construction of roads, economic facilities) are dominant in the formation of landslides in different landscape zones. Originality. It is established that there is a dynamic coherence between the spatial change in natural conditions and human settlement and activity, which interact with each other to create prerequisites for the development of landslides. Practical value. This study is important from the point of view of understanding and mitigating the cause-and-effect relationship of landslide development for certain territories, and the results obtained can be useful in developing land use planning strategies, infrastructure development, and planning new construction works.

The spatiotemporal distribution and environmental suitability evaluation of Neolithic settlements in the Western Guanzhong Basin of China

Illustrating the relationship between past settlement changes and human-land could help us to understand the complex interactions among climate, human activities, and the environment. Based on archeological literature and fieldworks, this paper combines dating techniques and GIS analysis to explore the spatial and temporal distribution characteristics and human diffusion of Neolithic settlements in the Western Guanzhong Basin (WGB), and to quantitatively analyzes the relationship between human activities and natural geographic factors by index model. The results show that: (1) There was a continuity of Neolithic cultures in the WGB and the absolute chronological sequence of human activities ranges from 7500 to 3900 a BP; (2) The distribution of settlements tends to be on river terraces and Loess tableland, and with the evolution of Neolithic cultures, human activities shifted from near-water to far-water distributions and expanded to areas of high gradient. The center of activity of the settlement spreads from a single nucleus (the Wei River) to multiple nuclei (the Wei River, the Qian Rivers, and the Qishui River) and back to a single nucleus on the northern bank of the Wei River in the area of present Qishan-Fufeng, laying the foundation for the development and strength of the Western Zhou Dynasty Cultures in this area; (3) The suitability level of the natural geographic environment in the WGB gradually decreased from the Wei River to the north and south, and settlements were mainly distributed in the highly and moderately suitable zones; (4) It was found that as early as the Neolithic period, mankind had already grasped certain laws of nature, and the spatial distribution of settlements reflected mankind’s awareness of disaster avoidance and “compromise and reconciliation.”

Spatial and temporal evolution patterns and driving mechanisms of rural settlements: a case study of Xunwu County, Jiangxi Province, China

Urbanization and industrialization have driven rapid socio-economic development, leading to a significant population shift from rural areas to cities. This demographic transition has resulted in substantial changes in rural settlements, presenting considerable challenges for rural revitalization. Given the spatial differentiation, it is crucial to analyze the spatiotemporal evolution patterns and driving mechanisms of rural settlements under various development scenarios and at multiple scales within a county. Such analysis is essential for rational planning and sustainable development. This study analyzes the spatial and temporal evolution patterns and driving mechanisms of rural settlements in Xunwu County, Jiangxi Province, China, using land use dynamics, hot and cold spot analysis, and center of gravity migration models. The Multiscale Geographically Weighted Regression Model (MGWR) is employed to explore their transformation driving mechanisms. The results show that during 2010–2020 in the study area, the total change rate of rural settlements was 39.82%, with a dynamic degree of 2.87%. The average centroid of the settlements is located in Wenfeng Township, gradually migrating southeastward by 3.7 km. Cold spots are shrinking northward, while hotspots are gathering in Chengjiang Town. Socio-economic conditions dominate the evolution of rural clusters in this region, showing obvious spatial heterogeneity. This is followed by locational conditions that are weakening in influence, while the impact of natural geographical conditions exists in the northeast region. The research findings offer a scientifically rigorous and well-founded analysis of the evolution and driving mechanisms of rural settlements. This analysis provides a solid theoretical basis for policy planning in urban-rural integrated development and supports the sustainable growth of rural communities.

A heterogenous-source geoinformation system to manage climate-induced modifications on the landscape for sustainable development

Historical landscapes in Italy have been slowly changing over the centuries and this is because their features, once fixed into specific shapes, were perpetuated until new economic and social developments occurred. Yet, in the Alpine region, this territorial organisation underwent sudden changes after World War II (WW II), resulting in a loss in population and traditional agropastoral production in favour of skiing plants and holiday houses. Moreover, the loss of traditional knowledge pertaining to environmental behaviour has resulted in the urbanisation of lands that are vulnerable to extreme events. In turn, this has hindered sustainable urban development. Nowadays, modern mapping technologies enable the state of the landscape to be assessed before, during, and after extreme events, the increased frequency of which may be related to climate change. The case study examined in this paper is the flood that hit Limone Piemonte, Italy, between the 2nd and 3rd October 2020. On that occasion, an aerial survey of the affected areas was carried out using Uncrewed Aerial Vehicles (UAV) a few weeks after the event. Spatial analyses were also performed based on very high-resolution satellite imagery acquired a few days after the event in order to determine where to plan more detailed three-dimensional (3D) surveys. This has enabled assessments of damages at different map scales to be performed. Thanks to the availability of pre-event multitemporal cartographic reference datasets, it was possible to monitor the historical evolution of the affected areas. It was possible to assess the vulnerable areas before the event, as well as to evaluate the morphological and settlement changes after the disaster. Therefore, one of the goals of this manuscript is to demonstrate that geoinformation systems are among the primary technical tools used to analyse environmental and climatic alterations that impact landscapes. Finally, a 3D model of the affected areas was produced, fulfilling another goal of the research by providing the public administration with a sustainable and innovative tool for territorial and landscape management, in accordance with the 11th pillar of the United Nations Sustainable Development Goals (UN SDGs).

Spatio-temporal changes in rural settlements: A case study of the Bošácka dolina valley

Spatio-temporal changes in rural settlements: A case study of the Bošácka dolina valley

Investigation of the Temperature and Horizontal Freezing Force of Loess in Three-Dimensional Freezing.

Seasonal frozen soil has significant impacts on changes in soil mechanical properties, settlement, and damage to foundations. In order to study variations in the temperature and horizontal freezing force of loess during three-dimensional freezing, a three-dimensional freezing model test of loess was carried out. This experiment analyzed and studied the soil temperature change distribution characteristics, horizontal freezing force distribution rules, and water migration phenomena caused by temperature. The research results show that the temperature change in soil samples exhibits a "ring-like" decrease from the outside to the inside. When the soil temperature reaches the supercooling point, the cooling curve jumps and rises, and this is accompanied by a stable section with constant temperature. In the late freezing period, the temperature rate drops slowly. Under the action of freezing, the horizontal freezing forces at different positions have similar change characteristics and can be divided into four change stages: stable stage, rapid freezing stage, "secondary" freezing stage, and freezing-shrinkage-rebound stable stage. At lower moisture contents, loess samples undergo freeze-thaw shrinkage during the freezing process. During the rapid freezing stage of soil samples, the water in the soil sample migrates and causes secondary freezing. After the rapid freezing stage, the soil temperature continues to decrease, and the horizontal freezing force no longer decreases.

Deformation analysis of ground and existing tunnel induced by overlapped curved shield tunneling

The deformation caused by tunnel excavation is quite important for safety, especially when it is adjacent to the existing tunnel. Nevertheless, the investigation of deformation characteristics in overlapped curved shield tunneling remains inadequate. The analytical solution for calculating the deformation of the ground and existing tunnel induced by overlapped curved shield tunneling is derived by the Mirror theory, Mindlin solution and Euler-Bernoulli-Pasternak model, subsequently validated through both finite element simulation and field monitoring. It is determined that the overcutting plays a crucial role in the ground settlement resulting from curved shield tunneling compared to straight shield tunneling. The longitudinal settlement distribution can be categorized into five areas, with the area near the tunnel surface experiencing the most dramatic settlement changes. The deformation of the existing tunnel varies most significantly with turning radius compared to tunnel clearance and grouting pressure, especially when the turning radius is less than 30 times the tunnel diameter. The tunnel crown exhibits larger displacement than the tunnel bottom, resulting in a distinctive 'vertical egg' shape. Furthermore, an optimized overcutting mode is proposed, involving precise control of the extension speed and angular velocity of the overcutting cutter, which effectively mitigates ground deformation, ensuring the protection of the existing tunnel during the construction.

Study on fissure evolution of overlying rock in lower protective mining

Protective layer mining is the most effective and economical technical measure to prevent coal and gas outburst accidents. At present, in the study of multiple concentrated coal layer stress, plastic damage and mining pressure discharge range, there are problems such as less research on the protection effect of protective layer and less measured measurement points resulting in large experimental error. In view of the above problems, taking the 2305 working face of a Shanxi mine as the test mine, the crack evolution characteristics of downhole drilling were detected by this method, by means of the deep base point technology, and study the plastic damage, pressure relief characteristics and expansion characteristics in the mining process of protective layer, the findings suggest that, the crack development of the protective layer is mainly characterized by small width and quantity, after protective exploitation, the number of width and number of cracks were significantly increased, the injection is three times higher than before the protective mining, the degree of fissure development is greatly improved. The settlement change of each rock layer on the basic top presents periodic and nonlinear changes, divided into the initial deformation, violent deformation, deformation and decline of the three periods; the plastic damage area, pressure relief curve and expansion curve of protective layer are “saddle type”, the overall pressure discharge rate of the protected layer has decreased by 60%, to meet the requirements of the critical value of expansion rate in the detailed rules for preventing coal and gas outburst, the protective layer mining technology applies to other working faces of the coal mine.

Spatial-temporal response of the regional ecological quality to urban settlement development

ABSTRACT Based on the objective evaluation of the regional ecological quality (Urban Cluster in Mid-inner Zhejiang) by Remote Sensing based Ecological Index (RSEI), it was proposed to study the spatial-temporal response of the regional ecological quality to the urban built-up areas, impervious surface, land use and “production-living-ecological” space under urban settlement change to quantitatively describe the mechanism of human activities’ influence on the regional ecology. The results showed that: (1) From 1985 to 2020, the RSEI of the Urban Cluster in Mid-inner Zhejiang was above 0.50 as a whole, showing a trend of first decreasing and then increasing with a slight decrease in some parts. (2) From the perspective of the urban built-up areas, it was dominated by ecological level 2–3, gradually changing from ecological level 3 to ecological level 2. (3) From the perspective of the impervious surface, it was dominated by ecological level 2–3, accounting for more than 75.00% of the total study area. (4) From the perspective of land use, the cropland, forestland, water and construction land were mainly ecological level 2–4, 3–4, 3–4 and 2–3. (5) From the perspective of “production-living-ecological” space, production space, ecological space and living space were dominated by ecological level 3, 3–4 and 2–3. The results can deepen the understanding of the impact of urban settlement development on the regional ecological quality, avoid the unbalanced situation of blindly pursuing socio-economic development while ignoring the ecological environment, which scientifically helps the sustainable construction and high-quality development of the Urban Cluster in Mid-inner Zhejiang.

Temporal Characterization of Land Use Change and Land-scape Processes in Informal Settlements in the City of Cape Town, South Africa

Temporal Characterization of Land Use Change and Land-scape Processes in Informal Settlements in the City of Cape Town, South Africa

Mechanical Response in Existing Structure under Varied Subsurface Excavation Techniques

With the slowdown of urban incremental construction in China, reinforcement and renovation of existing buildings have become a hot topic in the fields of engineering and theoretical research. Underpinning pile foundations and underground excavation are commonly used methods for foundation renovation and reinforcement in existing buildings reinforcement and renovation projects. Nevertheless, there remains a dearth of relevant research concerning the effects of different excavation methods on the stability of existing structures during foundation reinforcement and underground space excavation. In the context of existing building pile foundation underpinning and underground excavation, this paper adopts a numerical simulation research method based on the modification of experimental model parameters, and it compares the overall stress changes and settlement of the underpinning pile foundation and the building under two modes of lateral and vertical excavation. The results indicate that there is a good agreement between the stress and settlement changes of the components in the indoor model experiment and the finite element simulation. Both excavation methods show that lateral and vertical excavation will generate maximum stress on the bottom components of the upper structure and the upper part of the pile. In terms of differences, vertical excavation will cause greater overall settlement of the building, but the settlement in different areas is basically the same. On the other hand, lateral excavation will have smaller overall settlement but may cause the structure to tilt. At the same time, lateral excavation will cause greater stress changes in the columns in the structure. Based on these findings, relevant engineering suggestions are provided to choose different excavation methods and strengthen existing buildings.

Study on the Influence of Buried Depth on the Deformation of Bridge Approach Slab

The setting of the bridgehead slab can effectively alleviate the harm caused by the bridgehead bump, but the secondary bump may occur due to the fracture and void of the slab. Given the above problems, the influence of buried depth on the deformation of the bridge approach slab is studied through theoretical analysis and numerical simulation. The results show that compared with the conventional slab, the shear force of the slab is reduced and the service life is increased when the slab is deeply buried. The deep-buried slab can help to reduce the differential settlement of the road-bridge transition section and alleviate the phenomenon of vehicle bumping at the bridgehead. And the deeper the buried depth of the slab, the more gentle the settlement change of the transition section of the bridge.

Spatiotemporal analysis of land cover change, projection, and fragmentation: an application of Google earth engine and machine learning approach on Baraitali forest, Bangladesh

ABSTRACT Understanding the spatiotemporal dynamics of land cover/use change and forest fragmentation from 1981 to 2021 across the Baraitali Forest was very crucial for modeling future land cover, formulation of sustainable and robust forest/land-management strategies, and policy. The study adopted a mixed modern tool of Google Earth Engine platform, Machine Learning Algorithms, ArcGIS software, Land Change Modeller of TerrSet software, and FRAGSTATS programs. The study revealed that total land cover from 1981 to 2021 found a negative change in vegetative coverage, and a positive change in settlement which was more visible within the 6 land cover classes. Projections of future land cover for the next 10 years anticipate that vegetation coverage will be reduced by 65.96 ha, while settlement will be enhanced by 41.91 ha in 2031. The study also found conversions/transition of land cover throughout the research area. Overall change of spatiotemporal patterns was leading to substantial forest fragmentation. The overall accuracy and Kappa statistics for all the supervised land cover classifications were satisfactory. The study will fill an information gap by providing the revealed information at national and regional scales and may contribute to understanding of global change.

Study on the Spatial and Architectural Morphological Characteristics of Buyei Traditional Settlements and Their Sustainable Development Strategies

The development of traditional settlements and architecture in China has changed along with the acceleration of the urbanization process, especially the changes are more obvious in the areas inhabited by ethnic minorities. We take the traditional Buyei settlement space and architectural form as the object of research, summarize its characteristics, and study the development and change of the traditional Buyei settlement after the reform and opening up, summarize the characteristics of the traditional Buyei settlement, and put forward the suggestions for the protection and construction of the settlement, which is of great significance to the protection of national culture and the construction of "beautiful countryside". The promotion of ecological civilization is an important part of the current social and economic development, and the traditional architecture of the Buyi people contains the concepts of the unity of man and nature, harmony between man and nature, and respect for nature, which should become an important part of the construction of China's ecological civilization. Especially in the context of rural revitalization, analyzing the sustainable development strategy of the vast minority areas is necessary for balancing economic development and ecological civilization, and can play a positive role in promoting urban-rural integration, accelerating rural construction and realizing green development.

Archaeobotanical data from the Sabor Valley reveal shifting moments in landscape and agriculture in NW Iberia during the Holocene

NW Iberia is dominated by Atlantic climate areas that favour pollen preservation, useful for palaeoecological studies. However, the region also includes Mediterranean sectors in which preservation of such palaeoenvironmental evidence is more difficult. To overcome these constraints, archaeological plant macroremains can be used to help characterize flora and vegetation dynamics at a local and regional level. To fill the gap in knowledge in an understudied Mediterranean region, a large archaeobotanical study was conducted at the river Sabor valley, NE Portugal. With 13 archaeological sites sampled for charcoal, fruits and seeds, it allowed the study of vegetation throughout the Holocene, starting in the Mesolithic up to Modern times, with some chronological gaps. Tree taxa dominates the older period and an expansion of shrubby taxa since Bronze age was observed. Diversification of plants used during the Iron Age and Roman period suggests an intensification of resources exploitation and deforestation. These trends seem to be related with changes in human settlements and productive strategies. During Prehistory, agricultural fields were established in flat and wide areas, and, during Iron Age, fortified granaries were used to store large amounts of grains, particularly free-threshing wheat. Drastic changes in settlement during Roman times and the establishment of small farms producing wine and/or olive oil were testified by the occurrence of Olea and Vitis in both anthracological and carpological datasets. Data from more recent periods is scarce. Results highlight that the combination of several proxies and integration of archaeological evidence helps to understand ecological dynamics in areas without pollen data and contributes to the characterization of heterogeneous areas under diverse climatic conditions and with a variety of social trends.

Spatially explicit downscaling and projection of population in mainland China

Spatially explicit population data is critical to investigating human-nature interactions, identifying at-risk populations, and informing sustainable management and policy decisions. Most long-term global population data have three main limitations: 1) they were estimated with simple scaling or trend extrapolation methods which are not able to capture detailed population variation spatially and temporally; 2) the rate of urbanization and the spatial patterns of settlement changes were not fully considered; and 3) the spatial resolution is generally coarse. To address these limitations, we proposed a framework for large-scale spatially explicit downscaling of populations from census data and projecting future population distributions under different Shared Socio-economic Pathways (SSP) scenarios with the consideration of distinctive changes in urban extent. We downscaled urban and rural population separately and considered urban spatial sprawl in downscaling and projection. Treating urban and rural populations as distinct but interconnected entities, we constructed a random forest model to downscale historical populations and designed a gravity-based population potential model to project future population changes at the grid level. This work built a new capacity for understanding spatially explicit demographic change with a combination of temporal, spatial, and SSP scenario dimensions, paving the way for cross-disciplinary studies on long-term socio-environmental interactions.

Impact of small-angle shield undercrossing on existing tunnels

A three-dimensional finite element model was developed to investigate the effects of small-angle tunnels on existing tunnels in terms of surface settlement, arch bottom settlement, and ellipticalization of existing tunnel linings. The model simulated two small-angle tunnels crossing two existing tunnels. The maximum surface subsidence was observed at the recently excavated tunnel centers. The presence of existing tunnels reduced surface subsidence caused by ring-by-ring excavation. Surface settlement followed a “W” curve pattern, with two local minima gradually getting close as the tunnel was excavated. The maximum value of the arch bottom settlement of the existing tunnel gradually approached the intersection of the existing tunnel and the newly excavated tunnel. When the absolute value of the rate of change of the arch bottom settlement was high, the tunnel produced a large inter-ring misalignment. The line connecting the centers of the existing tunnel and recently excavated tunnel was parallel to the major axis direction of the ring after the deformation of the lining on the existing tunnel. Therefore, a small-angle tunnel passing through an existing tunnel may result in misalignment and torsion of the existing tunnel, requiring careful monitoring of the inter-ring bolt force to ensure safety.

Unilateral high-riding vertebral artery is associated with asymmetric morphological changes of the atlantoaxial joint: a novel risk factor for atlantoaxial osteoarthritis.

This study aimed to investigate the association between unilateral high-riding vertebral artery (HRVA) and morphological changes in the atlantoaxial joint (AAJ) and to determine whether unilateral HRVA is a risk factor for atlantoaxial osteoarthritis (AAOA). We conducted a retrospective analysis of 2496 patients admitted to our medical center between January 2020 and December 2022 who underwent CT imaging of the cervical spine. Two hundred and seventy-two patients with unilateral HRVA (HRVA group) were identified and a respective 2:1 age- and sex-matched control group without HRVA was built. Morphological parameters, including C2 lateral mass settlement (C2 LMS), C1/2 coronal inclination (C1/2 CI), lateral atlanto-dental interval (LADI), and C1/2 relative rotation angle (C1/2 RRA) were measured. The degree of AAOA was recorded. Risk factors associated with AAOA were identified using univariate and multivariable logistic regression analyses. The study included 61.4% women, and the overall average age of the study population was 48.7years. The morphological parameters (C2 LMS, C1/2 CI, and LADI) in AAJ were asymmetric between the HRVA and the non-HRVA sides in the HRVA group (p < 0.001). These differences in parameters (d-C2 LMS, d-C1/2 CI, and d-LADI) between the HRVA and the non-HRVA sides, and C1/2 RRA were significantly larger than those in the control group. Eighty-three of 816 patients (10.2%) with AAOA had larger values of d-C2 LMS, d-C1/2 CI, d-LADI, and C1/2 RRA compared with the patients without AAOA (p < 0.05). The multivariable logistic regression analysis indicated that unilateral HRVA [adjusted odds ratio (OR) = 2.6, 95% CI: 1.1-6.3, p = 0.029], age in the sixth decade or older (adjusted OR = 30.2, 95% CI: 16.1-56.9, p < 0.001), women (adjusted OR = 2.1, 95% CI: 1.0-5.6, P = 0.034) were independent risk factors for AAOA. Unilateral HRVA was associated with asymmetric morphological changes of nonuniform settlement of C2 lateral mass, lateral slip of atlas, and atlantoaxial rotation displacement. Besides age ≥ 60years and females, unilateral HRVA is an independent risk factor for AAOA.

ANALISIS DAMPAK PERUBAHAN PENGGUNAN LAHAN PERKOTAAN TERHADAP URBAN HEAT ISLAND DI KECAMATAN KEDATON

The Urban Heat Island phenomenon is defined as a form of local climate change. In the formation of the Urban Heat Island phenomenon, there are several factors, namely changes in land use, vegetation density, building density, and vehicle emissions. Dense development areas that have caused changes in land use, settlements, and transportation activities have begun to accumulate in Kedaton District. Kedaton District is included in the activity center area so that changes in land use from 2017 to 2022 occur significantly, which can cause an increase in urban temperatures. This study aims to analyze the impact of changes in urban land use on Urban Heat Island in Kedaton District. The variables used are land use, surface temperature, vegetation density, building density, motor vehicle intensity, and motor vehicle emissions. The analytical methods used are LST, NDVI, NDBI, road service level analysis, vehicle emission analysis, and correlation analysis. The results of the analysis show that the impact of changes in land use will result in a 76% decrease in vegetation density in 2022, a 95% increase in building density, and a 99% increase in vehicle emissions. The impact of changes in land use has contributed to the distribution of urban heat islands in Kedaton District. To minimize the impact of changes in use on the Urban Heat Island in Kedaton District, mitigation efforts based on the resilient city concept are needed, namely the addition of private green open spaces, reflective roof paint in densely populated areas, and optimizing public transportation.

Force analysis and treatments for Lidong tunnel of Renxin expressway crossing karst caves

There are several large karst caves at haunch part of the Lidong Tunnel during construction, together with inrush water due to high pressure within these caves. In light of it, this paper takes YK342+113 section as an example and adopts finite difference software FLAC 3D, so as to analyze tunnel deformation when crossing karst caves under six different working conditions, including with or without karst cave, before and after karst treatment, along with support locations. According to analysis results: First, the wall rock mainly had deformation at tunnel vault when evacuating at the third bench, which is a critical monitoring focus for tunnel construction; Second, karst cave treatment contributed to better conduct forces on both sides of wall rock, thus reducing vault settlement, while not affecting horizontal convergence and upturn of vaults; Third, treatment measures were proved to be effective in minimizing wall rock deformation by comparing deformation curves under different conditions; Fourth, after treatment measures, the angular points within the cave’s chamber had stress concentration, which might cause secondary collapse. Field monitoring data revealed that the final settlement of the tunnel vault was relatively consistent with the numerical analysis results, with a distinct change in daily settlement after initial support construction. By integrating numerical analysis and field monitoring, the rationality of the karst treatment plan was fully verified, providing a valuable reference for similar projects.