Spatial Differences of Coastal Urban Expansion in China from 1970s to 2013

As the ′economic engines′ of China,coastal cities have developed and expanded considerably since the 1970 s.In this study,information on the urban expansion process of Chinese coastal cities from the 1970 s to 2013 was retrieved.Through the analysis of stage characteristics,spatial expansion modes,influences on land use,centroid shifts,and spatial morphological evolutions,the spatial differences of coastal urban expansion were revealed.Results indicate that 1) the expansion stages of southern coastal cities are more complex than those of northern coastal cities,and the expansion ranges and speeds of the former are far higher than those of the latter;2) the spatial expansion of southern coastal cities mostly adopt a single mode,whereas northern coastal cities mostly adopt a mixed mode;3) significant spatial differences in the occupations of different land sources exist between the south and the north along the coastline;4) the centroid of coastal cities tends to migrate toward the coastline,and the centroid shift distances of southern coastal cities are clearly higher than those of northern coastal cities;and 5) the spatial morphology of southern coastal cities tends to be compact,whereas that of northern coastal cities tends to be loose.Policies have a powerful significance in terms of guiding urban expansion and its spatial differences in coastal cities.Urban expansion in coastal cities will encounter new opportunities and challenges under the guidance of new types of urbanization strategies.

Investigation of English learning strategy employed by senior middle school students in Zhanjiang City： A comparison of students from urban and rural areas

After a review of learning strategy research in China and abroad, this paper made an investigation on the differences in use of learning strategies reported by urban and rural students from four middle schools in Zhanjiang city. The investigation revealed the following findings： urban students employ cognitive and social strategies more frequently than rural students; urban students reported a wider range of strategies compared with their rural peers; urban students of intermediate achievements employ more social strategies than their rural peers, while rural students use affective strategy significantly more often; urban and rural students reported different patterns of gender difference.

Regional differences of urbanization in China and its driving factors

After more than 30 years of rapid urbanization, the overall urbanization rate of China reached 56.1% in 2015.However, despite China's rapid increase in its overall rate of urbanization, clear regional differences can be observed. Furthermore, inadequate research has been devoted to in-depth exploration of the regional differences in China's urbanization from a national perspective, as well as the internal factors that drive these differences. Using prefecture-level administrative units in China as the main research subject, this study illustrates the regional differences in urbanization by categorizing the divisions into four types based on their urbanization ratio and speed(high level: low speed; high level: high speed; low level: high speed; and low level: low speed). Next, we selected seven economic and geographic indicators and applied an ordered logit model to explore the driving factors of the regional differences in urbanization. A multiple linear regression model was then adopted to analyze the different impacts of these driving factors on regions with different urbanization types. The results showed that the regional differences in urbanization were significantly correlated to per capita GDP, industry location quotients, urban-rural income ratio,and time distance to major centers. In addition, with each type of urbanization, these factors were found to have a different driving effect. Specifically, the driving effect of per capita GDP and industry location quotients presented a marginally decreasing trend, while main road density appeared to have a more significant impact on cities with lower urbanization rates.

Quantifying the contribution of activity patterns to PM_(2.5)exposure inequity between urban and rural residents by a novel method

PM_(2.5)pollution variations in different microenvironments would result in PM_(2.5)exposure inequity between rural and urban residents.In this study,the real-time PM_(2.5)exposure of urban and rural residents in China was examined based on portable PM_(2.5)sensors together with activity patterns derived from questionnaire surveys,with a focus on students and senior citizens who are sensitive to air pollution.The results showed that PM_(2.5)exposure varied significantly among different resident groups,with higher PM_(2.5)exposure of rural residents than those of urban residents.PM_(2.5)exposure peaks mostly occurred during(Accompanied)cooking activities owing to strong emissions.Sleeping and resting were the main activities that affected PM_(2.5)exposures of different resident groups,accounting for 60.7%-94.5%of total daily exposures.Furthermore,the long duration of sleeping makes it the predominant activity contributing to PM 25 exposure inequity.It is necessary to obtain point-to-point respiratory volume(respiratory rate)data when measuring real-time PM_(2.5)exposure data and incorporate respiratory volume(respiratory rate)into the analysis of PM_(2.5)exposure.For the first time,this study quantified the PM_(2.5)exposure inequality based on a novel method and can provide useful information for further studies on the exposure inequity.

The Impact of COVID-19 on the Dietary Diversity of Children and Adolescents:Evidence from a Rural/Urban Panel Study

This paper offers the first empirical evidence of the impact of COVID-19 on dietary diversity among children and adolescents in urban and rural families by using panel data collected in 2019(before COVID-19)and 2020(during COVID-19)in northern China.Our study uses panel data from 2,201 primary school students and 1,341 junior high-school students to apply the difference in differences(DID)method to estimate the impact of COVID-19 on dietary diversity among students in urban and rural families.We found that the dietary diversity score(DDS)of rural students decreased by 0.295 points(p<0.01)compared with that of urban students during COVID-19.Specifically,COVID-19 significantly reduced the frequency of rural students'consumption of vegetables by 1.8 percent,protein-rich foods such as soybean products and nuts by 6.0 percent,meats by 4.0 percent,aquatic products by 6.7 percent,and eggs by 5.3 percent,compared with urban students.Further,COVID-19 had a significant negative effect on the dietary diversity of students from low-and middle-income groups,with the DDS of the low-income group decreasing by 0.31 points(p<0.01)and that of the middle-income group by 0.12 points(p<0.1).