The Natural Environment Suitability and the Suitability Degree of Human Settlements in Mid-southern Liaoning Urban Agglomerations,China,in Relation to the Population Distribution

Human settlement is a necessary factor for human survival and development.The scientific assessments of the natural suitability and appropriateness of human settlements contribute to addressing the discord between ecological environments and economic development and fostering sustainable development in the relationship between humans and nature.Building upon established methods for assessing human settlement suitability,this study investigated the natural suitability of the living environment in the urban agglomeration of mid-southern Liaoning.Based on this exploration,the suitability of the degree of human settlements for the population distribution in the study area from 2000 to 2020 was calculated.The results revealed three important points.(1)Nearly one-fifth of the study area,the area around the offshoot of Changbai Mountain,is a critically suitable area.More than half of this area,generally the buffer zone connecting the Liaohe Plain and the offshoot of Changbai Mountain,is generally suitable for human settlements.The proportion of suitable areas is only 25.53%,mostly on the Liaohe Plain along the Liaodong Peninsula by the Yellow Sea.(2)The overall spatial distribution of human settlement exhibits a pattern that is moderate-low in the middle and high on both sides;and higher in the southern part and lower in the northern part.(3)The human settlement suitability degree is higher in the western regions and lower in the eastern regions,with Shenyang and Panjin in the west having the highest suitability,while Benxi in the east exhibits the lowest habitat suitability.From 2000 to 2020,except for Shenyang and Panjin where suitability remained constant,the suitability degree of other cities has improved.Among them,Dandong experienced the most significant increase in suitability.

Evaluation on the human settlements environment suitability in the Three Gorges Reservoir Area of Chongqing based on RS and GIS

To explore geographical differences in quantitative characteristics and spatial pattern of human settlements environmental suitability （HSES） in the Three Gorges Reservoir Area （TGRA）, terrain, climate, hydrology, vegetation and other natural factors were selected to build the livable environmental evaluation, and the quantitative analysis was conducted through Remote Sensing（RS） and Geographic Informational System （GIS） to reveal geo- graphical characteristics and spatial patterns of HSES. The results are obtained as follows： （1） inhabitants of the TGRA of Chongqing are concentrated in the area with moderate h.igh HSES, which is 78% of the total population distributed in 48% of the study area; （2） the HSES is closely related to the terrain, and it forms an arc-banded spatial succession pattern： relatively low in the northeast and the southeast while comparatively high in the west and the south; （3） large numbers of people are distributed in the area with low suitability （with higher population density than the average of the western China）, but economic development level in these areas is quite low. Moreover, these areas are ecological sensitive and fragile, many kinds of eco-environmental problems have been caused by human activities. Therefore, population migration and layout are reasonable options for the development of these areas.

Environmental suitability evaluation for human settlements in an arid inland river basin： A case study of the Shiyang River Basin

The study employs slope, aspect, relief degree of land surface, land use, vegetation index, hydrology and climate, as evaluation indexes to set up the Human Settlements Environmental Index （HEI） model to evaluate the environmental suitability for human settlements in the Shiyang River Basin. By using GIS spatial analysis technology, such as spatial overlay analysis, buffer analysis and density analysis, the environmental suitability of the human set- tlement spatial situation and spatial pattern are established to analyze their spatial distribution The results show that the index of suitability for human settlements in the Shiyang River Basin is between 17.13 and 84.32. In general, suitability for human settlements decreases from the southwest to the northeast. Seen from an area pattern, the suitable region is mainly distributed in the Minqin oasis, Wuwei oasis and Changning basin, which are about 1080.01 km2 and account for 2.59% of the total area. Rather and comparatively suitable region is mainly distributed around the counties of Gulang, Yongchang and north of Tianzhu, which is about 1100.30 km2. The common suitable region is mainly distributed outside the counties of Yongchang, Jinchuan and most parts of Minqin County, which are about 23328.04 km2, accounting for 56.08% of the total area. The unsuitable region is mainly distributed upstream and to the north of the river, which is about 9937.60 km2, accounting for 23.89% of the total area. Meanwhile, the least suitable region is distributed around the Qilian Mountains, which are covered by snow and cold desert and lie in the intersecting area between the Tengger Desert and Badain Jaran Desert. The total area is about 6154.05 km2, accounting for 14.79% of the total area. Suitable regions for human habitation are mainly distributed around rivers in the form of ribbons and batches, while others are scattered. The distribution pattern is iden- tical to the residential spatial pattern. In addition, the relationships between HEI and other factors have been analyzed. There is a clear logarithmic correlation between the residential environment and population, that is, the correlation coefficient between the evaluation valueand population density reaches 0.851. There is also a positive correlation between the residential environment and economy, which reaches an evaluation value of 0.845 between the residential environment and GDP. Results also show that the environment is out of bearing with the existing population in Shiyang River Basin. Spatial distribution of population is pro- foundly affected by severe environmental problems, such as the expanded deserts, the hilly terrain and the changing climate. Surface water shortage and slow economic growth are bot- tlenecks for suitable human settlement in the Shiyang River Basin. Combining these prob- lems with planning for construction of new country and the exploitation of local land, some residential areas should be relocated to improve the residential environment.