Spatial-temporal differentiation and influencing factors of rural settlements in mountainous areas: an example of Liangshan Yi Autonomous Prefecture, Southwestern China

Rural settlement is the basic spatial unit for compact communities in rural area. Scientific exploration of spatial-temporal differentiation and its influencing factors is the premise of spatial layout rationalization. Based on land use data of Liangshan Yi Autonomous Prefecture(hereinafter referred to as Liangshan Prefecture) in Sichuan Province, China from 1980 to 2020, compactness index, fractal dimension, imbalance index, location entropy and the optimal parameters-based geographical detector(OPGD) model are used to analyze the spatial-temporal evolution of the morphological characteristics of rural settlements, and to explore the influence of natural geographical factors, socioeconomic factors, and policy factors on the spatial differentiation of rural settlements. The results show that:(1) From 1980 to 2020, the rural settlements area in Liangshan Prefecture increased by 15.96 km^(2). In space, the rural settlements are generally distributed in a local aggregation, dense in the middle and sparse around the periphery. In 2015, the spatial density and expansion index of rural settlements reached the peak.(2) From 1980 to 2020, the compactness index decreased from 0.7636 to 0.7496, the fractal dimension increased from 1.0283 to 1.0314, and the fragmentation index decreased from 0.1183 to 0.1047. The spatial morphological structure of rural settlements tended to be loose, the shape contour tended to be complex, the degree of fragmentation decreased, and the spatial distribution was significantly imbalanced.(3) The results of OPGD detection in 2015 show that the influence of each factor is slope(0.2371) > traffic accessibility(0.2098) > population(0.1403) > regional GDP(0.1325) > elevation(0.0987) > poverty alleviation(0). The results of OPGD detection in 2020 show that the influence of each factor is slope(0.2339) > traffic accessibility(0.2198) > population(0.1432) > regional GDP(0.1219) > poverty alleviation(0.0992) > elevation(0.093). Natural geographical factors(slope and elevation) are the basic factors affecting the spatial distribution of rural settlements, and rural settlements are widely distributed in the river valley plain and the second half mountain area. Socioeconomic factors(traffic accessibility, population, and regional GDP) have a greater impact on the spatial distribution of rural settlements, which is an important factor affecting the spatial distribution of rural settlements. Policy factors such as poverty alleviation relocation have an indispensable impact on the spatial distribution of rural settlements. The research results can provide decisionmaking basis for the spatial arrangement of rural settlements in Liangshan Prefecture, and optimize the implementation of rural revitalization policies.

Impact of human settlements quality on urban vitality based on multisource data:A case study of Shahekou District,Dalian,China

Urban geography has always been concerned about the influence of human settlements on urban vitality,but few studies reveal the influence of human settlements on urban vitality at a micro-scale.This paper analyzes the spatial distribution characteristics of human settlements’quality and urban vitality at the micro-scale using Geodetectors and geographic weighted regression to analyze the relationship between human settlements and urban vitality.The results are shown as follows:there is still a significant development space for human settlements quality in Shahekou District,with obvious spatial dependence characteristics and significant gaps between various systems;the urban vitality of Shahekou District has obvious timeliness,and the urban vitality undergoes significant changes over time,which is related to the human settlements quality.The spatial distribution presents a single core spatial distribution structure with strong relative stability.The spatial distribution of cold and hot spots shows a pattern of“high in the north and low in the south,high in the east and low in the west”,with an increasing trend from southwest to northeast;the reachability of public transport has a significant impact on urban vitality.Its synergy with other variables is the leading force forming the spatial distribution of urban vitality.The environmental system,support system and social system are the significant factors affecting the urban vitality of Shahekou District.

Spatial Protection and Development of Traditional Mountain Settlements from the Perspective of Self-organization : A Case Study of Anju Ancient Town in Tongliang District, Chongqing

Through literature research, field research and urban design analysis methods, based on the self-organization theory, the evolution characteristics of the settlement space of Anju Ancient Town with significant characteristics of traditional mountain settlements were analyzed, and then its internal and external influencing factors were summarized. Finally, appropriate protection and development strategies were proposed, such as reasonably planning functional zones, breaking through the single structure, and creating a good living cultural environment. The innovation of this study is that it integrates the self-organization theory into the cognition of traditional mountain settlement space, and discusses the connection between the mountain settlement space and the traditional regional context under the modern development concept, so as to seek the benign protection and reasonable development of traditional mountain settlement space.

Naming and Distribution of Traditional Mountain Settlements in Mentougou in Western Beijing

Settlement naming is an important carrier of settlement society and culture,carries regional culture,historical information,beliefs and other information,and is an important clue to understand regional culture and development characteristics.In this paper,the naming of traditional mountain settlements in Mentougou in western Beijing was studied through literature review and field research,and the correlation between the naming and distribution characteristics of the settlements was discussed to provide reference for the protection and construction of mountain settlements in Mentougou.

Spatiotemporal Interaction Between Rural Settlements and Cultivated Land in Karst Mountainous Area,China

Settlements and cultivated land are important production and living spaces in promoting rural revitalization.However,few studies have explored the relationship between rural settlements and cultivated land from spatiotemporal interaction perspective.This paper analyzed the spatiotemporal conversion and the interactive mechanism between rural settlements and cultivated land in a karst mountainous area(Qixingguan District of Guizhou Province)with fragile ecological environment in China during 2009–2018.The results showed that the expansion of rural settlements and the loss of cultivated land coexisted in Qixingguan District.Only 2.68%of the new cultivated land was reclaimed from rural settlements,whereas 85.45%of the new rural settlements occupied cultivated land.Six spatial expansion modes of rural settlements when occupying cultivated land were identified.Among these six modes,the area of the edge-expansion&along traffic roads(EA)mode accounted for 52.75%.The occupation by rural settlements made the cultivated land landscape more fragmented.The area ratio index of cultivated land to rural settlements(ARICR)of Qixingguan District averaged 18.75in 2009 and 17.21 in 2018,respectively.The ARICR reduced in all township administrative regions.Cultivated land with suitable slope condition for farming or without rocky desertification was more likely to be occupied by rural settlements.The probability of cultivated land occupied by rural settlements increased with the decrease of the distance to traffic roads,towns,and old rural settlements.The better the economic and social development of the township administrative regions,the more the ARICR decreased,while the richer the agricultural resources and the better the rural development of the township administrative regions,the less the ARICR decreased.The optimal reconstruction path of rural settlements,the comprehensive conservation path of cultivated land and the urban-rural integration development path in karst mountainous area were proposed.The findings would contribute to our understanding of the spatiotemporal interaction between rural settlements and cultivated land,and would provide a theoretical basis for promoting the coordinated development of rural man-land relationship and rural revitalization in karst areas.

Climate Change Adaptation and Historic Settlements: Evidence from the Old Town of Corfu

The Old Town of Corfu is an excellent example of a historic town and a World Heritage Site, distinguished by its authentic and unique character, as reflected in its Venetian-era fortifications and extensive historic building stock. Simultaneously, the Old Town of Corfu is also a vibrant modern city vulnerable to various pressures, including climate change. This paper aims to evaluate the effects of climate change on this modern city monument, assess its vulnerability using the Intergovernmental Panel on Climate Change’s methodology, and develop a comprehensive set of adaptation proposals. The methodology of this paper is based on the analysis of climate data for the Old Town of Corfu, from which the assessment of the extreme weather events and climate changes that pose the greatest threat to the Old Town and the assessment of its vulnerability to these threats are derived. The dense geometrical characteristics of the city’s structure, the intense pathology observed in the materials and structures of the historic building stock, problems in the existing electromechanical infrastructure, and the poor management of issues such as increased tourism and heavy traffic congestion are the primary factors that make the Old Town of Corfu vulnerable to the effects of climate change.

Natural environment suitability for human settlements in China based on GIS

With the degeneration of environment and acceleration of urbanization,human environment has attracted great attention worldwide.This paper sets up the Human Settlements Environment Index(HEI) model and evaluates the natural environment suitability for Human Settlements in China based on GIS technology.The results show that the HEI of China decreases from southeast to northwest in general,HEI is significantly correlated with population density at grid size and the correlation coefficient(r) between them reaches 0.93,which indicates that natural environment suitability for Human Settlements has a significant influence on population distribution.Most people in China mainly concentrate in areas with high natural environment suitability.The total suitable area is 430.47×104 km2,which accounts for nearly 45% of the total land area in China,while the proportion of people living in the area reaches 96.56%.With a population density of 18 people per square kilometer,the critical area is the transitional region for people to live in China.The critical area covers 225.11×104 km2 with a population of 41.12 million.The non-suitable area covers 304.42×104 km2 with a population of only 2.49 million.

Study on Extracting Information about Settlements Distribution in Western Jilin Province Based on Decision Tree Model

With western Jilin Province as the study region, spectral characteristics and texture features of remote sensing images were taken as the classification basis to construct a Decision Tree Model and extract information about settlements in western Jilin Province, and the manually-extracted information about settlements in western Jilin Province was evaluated by confusion matrix. The results showed that Decision Tree Model was convenient for extracting settlements information by integrating spectral and texture features, and the accuracy of such a method was higher than that of the traditional Maximum Liklihood Method, in addition, calculation methods of extracting settlements information by this mean were concluded.

Research on Spatial Distribution of Settlements in the Upper Reaches of the Minjiang River

Under the background of the uplift of the Qinghai-Tibet Plateau, the settlements in the upper reaches of the Min River are significantly affected by the mountain environment, and their spatial distribution is typical and representative. In this study, the relationship between settlements and topography, rivers and transportation, and the spatial distribution patterns of settlements, such as the aggregation and orientation characteristics of settlements, have been studied. The main conclusions include: 1) The settlement density decreases with the increase of elevation, slope, and distance from rivers and roads;76.25% and 63.17% of the settlements are distributed in the range of elevation 1500 - 3000 m and slope 6° - 25°, the upper reaches of the Min River are mostly alpine valley terrain, the bottom of the river has a low altitude, the landscape is undulating. The warm and humid climate is suitable for farming, conducive to agricultural production, and an ideal living environment for mountain residents. 2) The nuclear density of the settlement is distributed in strips along the axis of the river, and the closer to the river, the greater the nuclear density value. 3) Mathematical statistical methods were applied for the first time to realize the quantitative expression of the coupling of settlement and river direction. The influence of topographic conditions in different watersheds on the coupling degree of settlement extension and river flow direction was revealed. The slope of the fitted straight line between the settlement and river direction was 0.897, and the two directions were consistent. Except for the mainstream of the Min River, the larger values of the standard deviation ellipse flattening of settlements in each basin appeared in the upper reaches of the bay, and the overall trend showed a gradual decrease from the upstream to the downstream, which was consistent with the topographic change characteristics of the basin.

Human Settlements in Rural-urban Fringe

On basis of human settlements theory, the research explored status quo of human settlements theory in rural-urban fringe, and analyzed and concluded predicaments confronted by rural-urban fringe, laying foundation for human settle- ments theory of rural-urban fringe.

Research on the Green Planning in Rural Settlements of Hui Nationality in Central Ningxia

Targeted at the residence status in rural settlements of Hui people in central Ningxia Hui Nationality Autonomous Region, this research revealed that the construction of new countryside and the transformation of old countryside all have to be on the basis of present topography, landform, environment, social-economic level, education, religion, customs, living habits and so on. The primary goal of this research was to find a method of ecology, low energy consumption and sustainable development to bring the green planning implementation strategies, to provide guidance for sustainable planning in the rural settlements of Hui Nationality in central Ningxia.

Participation of Users in Traditional and Modern Turkish Settlements

When the development level of a city is determined, its residents＇ level of participation and support to social organizations, especially the voluntarily participation to civil organizations, are taken into account, as well as, their level of utilization from city services. It is beneficial to organize civil groups who are sensitive to urban and environmental issues. In traditional Turkish settlements, it can be talked about the existence of such an organization as a natural process in social organizations including moral and humanistic values. The feeling of belonging had raised the environmental quality both physically and socially. Respect to the nature and human was the main principle of these settlements. Such organizations has displaced with the written rules and official or civil organizations in modern urban settlements. In these organizations, participation of the users to urban planning decisions is not directly, but indirectly. As people who live in modern settlements do not participate to the planning and building process, they have not felt themselves belong to the place. The environmental quality and respect to the nature and human have been lessened in these modern settlements. This study focuses on the participation of users on planning and building housing environments in traditional and modern Turkish settlements and the comparison of them with their positive and negative results with the examples given.

Effectiveness of predicting tunneling-induced ground settlements using machine learning methods with small datasets

Prediction of tunneling-induced ground settlements is an essential task,particularly for tunneling in urban settings.Ground settlements should be limited within a tolerable threshold to avoid damages to aboveground structures.Machine learning(ML)methods are becoming popular in many fields,including tunneling and underground excavations,as a powerful learning and predicting technique.However,the available datasets collected from a tunneling project are usually small from the perspective of applying ML methods.Can ML algorithms effectively predict tunneling-induced ground settlements when the available datasets are small?In this study,seven ML methods are utilized to predict tunneling-induced ground settlement using 14 contributing factors measured before or during tunnel excavation.These methods include multiple linear regression(MLR),decision tree(DT),random forest(RF),gradient boosting(GB),support vector regression(SVR),back-propagation neural network(BPNN),and permutation importancebased BPNN(PI-BPNN)models.All methods except BPNN and PI-BPNN are shallow-structure ML methods.The effectiveness of these seven ML approaches on small datasets is evaluated using model accuracy and stability.The model accuracy is measured by the coefficient of determination(R2)of training and testing datasets,and the stability of a learning algorithm indicates robust predictive performance.Also,the quantile error(QE)criterion is introduced to assess model predictive performance considering underpredictions and overpredictions.Our study reveals that the RF algorithm outperforms all the other models with the highest model prediction accuracy(0.9)and stability(3.0210^(-27)).Deep-structure ML models do not perform well for small datasets with relatively low model accuracy(0.59)and stability(5.76).The PI-BPNN architecture is proposed and designed for small datasets,showing better performance than typical BPNN.Six important contributing factors of ground settlements are identified,including tunnel depth,the distance between tunnel face and surface monitoring points(DTM),weighted average soil compressibility modulus(ACM),grouting pressure,penetrating rate and thrust force.

Evaluating the suitability of different terrains for sustaining human settlements according to the local elevation range in China using the ASTER GDEM

The topographical suitability assessment of human settlements(SAHS) creates a solid foundation for regional population distribution and socio-economic development. Local elevation range(LER) is an important factor that can be used to assess the suitability of different terrains for sustaining human settlements. However, current digital elevation model(DEM)-based LER products suffer from some challenges typically because of their subjectively selected neighborhood scales and coarser spatial resolution. In this study, we initially determined the optimal statistical window and then calculated the appropriate LER with the finer resolution data of the Advanced Spaceborne Thermal Emission and Reflection Radiometer Global DEM(ASTER GDEM) products for China. Then, the appropriate LER was used to evaluate the topographical SAHS and its correlations with the national gridded population distribution(1 km × 1 km) in 2010. The results show that the optimal statistical window for calculating a 1 arc-second(about 30 m) resolution GDEM LER for China can be determined using a 51 × 51 grid unit(width × height) within a rectangular neighborhood, corresponding to an area of about 2.34 km^2. Secondly, the LER values in the southern and western China were greater than those of the north and east, showing a trend which consistently reflects the general spatial features of landforms. Finally, the relationship between GDEM LER and population density was highly correlated with the R^2 value of 0.81. It showed that 85.22% of the Chinese population was located in areas where the LER is lower than 500 m. The topographically suitable area within China decreased from the southeastern coastal zone towards the northwestern inland areas due to transition from plains and basins to plateaus and mountains. The total area of moderate to high suitable level was 423.84 × 10~4 km^2, or 44.15% of the total land area, with 88.17% of the national population. Our study demonstrates the usefulness of appropriate LER in evaluating the topographical SAHS as well as its significant impact on population distribution.

Productive functional evolution of rural settlements:analysis of livelihood strategy and land use transition in eastern China

In China, rural settlements are usually multifunctional complex of natural societies and they also play important productive function. This study explored the spatiotemporal evolution of the productive function of three rural settlements, i.e.,Hetaoyuan, Dawengshan, and Gaoqiao, in the Yimeng Mountain in Shandong province of eastern China.Residents lived in this three types of rural settlements were all involved in agricultural production(i.e., grain threshing, drying and storage), which had remained dominant in Hetaoyuan. Dawengshan became an industrial-oriented settlement, while Gaoqiao became a commercial-oriented settlement. This evolution was reflected in the livelihood strategy changes of rural households and the transition of rural settlements changes. The choice of livelihood strategy was affected by the livelihood assets and policies, which resulted in the spatiotemporal evolution of the productive function of rural settlements. This study can provide references for the implementation and adjustment of rural residential land consolidation policies and the improvement of production and the quality of rural life in future.

Spatial Pattern and Regional Types of Rural Settlements in Xuzhou City,Jiangsu Province,China

This paper principally focuses on the morphological differences,spatial pattern and regional types of rural settlements in Xuzhou City of Jiangsu Province in China.Using satellite images of Xuzhou City taken in 2007 and 2008 and models of exploratory spatial data analysis(ESDA) and spatial metrics,the paper conducts a quantitative analysis of the morphological pattern of rural settlements,and finds significant characteristics.First,rural settlements in Xuzhou City are significantly agglomerated in terms of their spatial distribution;meanwhile,there is significant variation in the geographical density distribution.Second,the scale of rural settlements in Xuzhou City is larger than the average in Jiangsu Province,and the histogram of the scale data is more even and more like a gamma distribution.There are a significant high-value cluster in the scale distribution,and local negative correlation between the scale and density distribution of rural settlements in Xuzhou City.Third,the morphology of rural settlements in Xuzhou City shows relative regularity with good connection and integrity,but the spatial variation of the morphology is anisotropic.Finally,according to the characteristics of density,scale,and form of rural settlements,the rural settlements of Xuzhou City are divided into three types:A high-density and point-scattered type,a low-density and cluster-like type and a mass-like and sparse type.The research findings could be used as the scientific foundation for rural planning and community rebuilding,particularly in less-developed areas.

Analyzing land use characteristics of rural settlements on the urban fringe of Liangjiang New Area, Chongqing, China

The objective of this paper is to analyze land use characteristics of rural settlements in urban fringe so as to provide references for optimizing the regional distribution of rural settlements, consolidating rural settlements, and coordinating urban-rural integrated development. The methods of spatial statistical analysis, buffer analysis, Ripley's K function, kernel density analysis based on GIS(Geographic Information System) were used to analyze the characteristics of scale, spatial differentiation and spatial patterns of the rural settlements in Liangjiang New Area in Chongqing Municipality of China. The fractal dimension formula was also developed to reflect fractal feature of the rural settlements. The results show that, the scale of rural settlements in Liangjang New Area takes on distinct characteristics of spatial differentiation along with changes in elevation, gradient, location, geohazards distribution, and the like. The fractal characteristic of rural settlements has obvious regional variations subject to the 6 factors of location in the Liangjiang New Area. Overall, the worse the terrain conditions are, the larger the fractal dimension values become. The better the locationconditions, the larger the fractal dimension values are. The spatial pattern in the township scale presents three kinds of distribution as being aggregated, uniform and random. In contract, the spatial pattern in the plaque scale displays a banding distribution from a general view with several aggregation zones centering on each town center. From the results, we can see that the characteristics of rural settlements in urban fringe are more complicated. For such kind of rural settlements in special regions, in the rural land consolidation more attention should be paid to improve the rural living environments and public services, as well as to promote the harmonious relationship between the urban and rural areas.

Suitability Evaluation of Rural Settlements Based on Accessibility of Production and Living： A Case Study of Tingzu Town in Hubei Prov- ince of China

Rural settlements are the main carriers of agriculture, rural areas and farmers; thus, optimizing the production and living space of rural settlements is highly significant to rural development. Taking the effective allocation of resources as the starting point, a suitability evaluation system of rural settlements, based on accessibility of production and living, was proposed in this study to provide scientific basis for the optimization of production and living space. The accessibility of production and living was measured by an im- proved two-step floating catchment area method, which considered proximity and availability based on the inclination of rural residents. The suitability evaluation system consisted of traditional suitability evaluation and newly proposed limiting factor identification based on the loss score proportion of suitability. Tingzu Town of Hubei Province, China, was chosen as the case study area. Based on the re- suits of the suitability evaluation system, corresponding suggestions on rural land consolidation, industry division, as well as the layout of health care and education facilities were proposed to optimize the production and living space of rural settlements in Tingzu Town. It is found that the suitability evaluation based on accessibility of production and living is more scientific and accurate than the traditional ones which significantly overestimate production and living convenience. Moreover, the limiting factor identification can help us put forward suggestions according to local conditions and bring about the highly targeted optimization of production and living space of rural settlements.

Failure mechanism of large-diameter shield tunnels and its effects on ground surface settlements

A new technique for the analysis of the three-dimensional collapse failure mechanism and the ground surface settlements for the large-diameter shield tunnels were presented.The technique is based on a velocity field model using more different truncated solid conical blocks to clarify the multiblock failure mechanism.Furthermore,the shape of blocks between the failure surface and the tunnel face was considered as an entire circle,and the supporting pressure was assumed as non-uniform distribution on the tunnel face and increased with the tunnel embedded depth.The ground surface settlements and failure mechanism above large-diameter shield tunnels were also investigated under different supporting pressures by the finite difference method.

Identifying the Static and Dynamic Relationships Between Rural Population and Settlements in Jiangsu Province, China

Rapid urbanization has triggered large rural population floating into cities, which in turn affects rural human-land relationships. The actual human-land relationship involves the coupling level of a time point and dynamic change of a time interval. However, few studies have identified the rural human-land relationship from these two perspectives. This study combined static coupling analysis with a dynamic decoupling model to analyze the relationships between rural population and settlements from 2009 to 2018 in Jiangsu Province, China. Although the static coupling degree in Jiangsu Province was relatively high, the decoupling analysis found that the rural human-land relationship in most counties was uncoordinated. There were 11 combination types based on the coupling and decoupling relationships. The most common two types(accounting for 76.74%) were recession decoupling with high-level coupling and strong decoupling with high-level coupling. Although the majority of counties had a high-level coupling degree, an uncoordinated change in rural population and rural settlements was observed in these counties. Counties with relatively reasonable human-land relationships accounted for only 12.79% of the total. The combination features for each type were identified and differential policies were proposed for optimizing human-land relationship in rural areas. This study would contribute to our understanding of the multiple relationships between rural population and settlements involved in different patterns and processes, and expect to provide theoretical and methodological support for promoting rural revitalization and sustainable development in practice.