Empirical Research on Carrying Capacity of Human Settlement System in Dalian City, Liaoning Province, China

Using the theories of population carrying capacity and ecological elasticity in other fields for reference, the connotation of regional human settlement system was defined from the viewpoint of the complex relationship among the factors such as regional population, resources, environment and economic and social development in the context of China′s rapid urbanization. Then the concept and characterization methods of the regional human settlement carrying capacity were proposed by means of population scale. Furthermore, a model of carrying capacity-pressure-state-response(CPSR) on regional human settlement system was established by referencing pressure-state-response(PSR) model, and the Catastrophe Theory was introduced to determine the corresponding standards of multi-criteria programming and evaluation. Taking Dalian City, Liaoning Province, China as an example, an empirical analysis on evaluation of human settlement system from 2000 to 2012 was carried out. The results showed that the carrying capacity of human settlement system in Dalian was fluctuating between 9.6 × 106 to 10 × 106 persons with a quantitative stage of the dynamic regulation. During the research period the load index of human settlement system in Dalian dropped from 0.96 to 0.84 with a lower pressure of human settlement system than the national average level. And the emergency response grades of human settlement system in Dalian were kept in grade Ⅱ(orange warning) or grade Ⅲ(yellow warning). Human settlement system of Dalian was in slight security state as a whole, but the load had a tendency of increase in recent years. The related departments should pay close attention to regional human settlement system and take active measures to improve human settlement by both intensity control and total quantity control. By comparison, analysis and discussion, it was considered that the results were basically accordded with the current situations of human settlement in Dalian, and the evaluation results were more reliable, visualized and easily applied in practice. Therefore, the above-mentioned concepts, characterization and evaluation methods of the regional human settlement system and carrying capacity could provide a new thought and method for quantitative evaluation of human settlement.

Elemental Composition of Atmospheric Particles in Winter at Datong City, Shanxi Province, China, and Its Impact on Beijing

Atmospheric particle samples were collected at an urban site of Datong, Shanxi Province, during December 2004 and their element concentrations at different sizes were analyzed by particle-induced X-ray emission (PIXE). Analysis of the observation data showed that particle pollution was heavy in winter at Datong and that concentrations of most elements were high in the coarse range. Factor analysis (FA) results indicated that the soil and dust, coal combustion dust, and industry dust are main sources for atmospheric particles in winter at Datong. The enrichment factors of element concentrations showed that particle pollution at Datong impacts the down-wind region-Beijing-in the dust season.

Seasonal waterbird population changes in Lashihai Lake in northwest Yunnan, China

We studied the waterbird population at Lashihai Lake, Yunnan Province, China, which is a Ramsar Site(Wetland of International Importance), to determine seasonal variation in the species composition and size of the waterbird population. The study was conducted at five selected spots along Lashihai Lake at the same time each week from August 2011 to September 2013. In total, 62 waterbird species were recorded, of which 38.71%, 35.48%, 16.13%, and 9.68% were winter migrants, passage visitors, residents, and summer migrants, respectively. We found important seasonal changes in waterbird species composition and population size. Waterbird species richness was highest from September to the following April, with the total species numbers peaking in December. Total individual numbers peaked twice from late November to early December and mid-to-late February. However, waterbird species and individual numbers were comparatively lower from May to August. The change in species composition was determined by the arrival and departure dynamics of winter migrants and passage visitors. Winter migrants primarily caused the periodic changes in population size. Of concern,species and overall waterbird numbers seemed to be lower than the numbers in historical records. The decline of waterbird numbers implies that environmental changes caused by the implementation of the dam upstream of Lashihai Lake may have had adverse effects on this waterbird population. This study confirms the existence of major seasonal changes in species composition and size of the waterbird population at Lashihai Lake. Furthermore, the findings demonstrate that this wetland is of high conservation importance for waterbirds using the Central Asian–Indian and Asian–Pacific migratory routes.

LETTERS

I am an Australian living in Quanzhou, Fujian Province. I am employed as an English conversation teacher in a local middle school. I enjoy reading China Today and would be interested in writing an article on my impression of Quanzhou, or my experiences as a teacher in middle school or other topics that may be of interest to your readers.

Analysis on Earthquake Emergency Material Preparation Demand Based on Earthquake Risk Evaluation Taking Datong City of Shanxi Province as an Example

The earthqnake emergency material preparation demand analysis can provide the scientific basis for all levels of governments to conduct reasonable and unified configuration of the emergency preparation resources, in order to further optimize the earthquake emergency ability construction to provide reference. This paper takes Datong City of Shanxi Province as an example, using the earthquake risk evaluation method, adopting the deterministic method and probabilistic method to conduct earthquake danger analysis, combined with the earthquake emergency rescue case and the previous scholars＇ research achievements, in order to study and analyze the earthquake emergency material preparation demand in different earthquake dangers.