Vegetation and climate changes in the Changjiang (Yangtze River) Delta, China, during the past 13,000 years inferred from pollen records

AbstractWe reconstructed the centennial climate changes for the period of 9–7 cal ka BP in the upper region of the Changjiang (Yangtze) River Delta plain. A general warming and wetting trend from 8560 to 7220 cal yr BP was indicated by the decrease in Quercus (deciduous) and increases in Quercus (evergreen), Pinus, and Polypodiaceae spores. However, there were several brief climate fluctuations. A notable palynological change, from regional assemblages dominated by arboreal pollen to local assemblages mainly consisting of nonarboreal pollen, reflects climate fluctuations. The key indices of Quercus (deciduous), Pinus, herbs, fern spores, and palynological concentrations showed similar signs of centennial climate fluctuations. We suggest that the climate changes of the Dongge Cave and Yangtze River Delta regions were mainly affected by the East Asian summer monsoon (EASM) during the period of 9–7 cal ka BP. The general warming trend may be associated with an intensified EASM, and solar activity may be one of the important factors driving the centennial climate changes. The ~8.2 ka event was also recorded in the Yangtze River Delta region, which suggests that there was a close relationship between the EASM and Greenland climate during the early Holocene.

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Palynological study on vegetation and climatic change in the subaqueous Changjiang (Yangtze River) delta, China, during the past about 1600 years

Geosciences Journal ◽

10.1007/bf02910329 ◽

2006 ◽

Vol 10 (1) ◽

pp. 17-22 ◽

Cited By ~ 5

Author(s):

Sangheon Yi ◽

Yoshiki Saito ◽

Zhongyuan Chen ◽

Dong Yoon Yang

Keyword(s):

Climatic Change ◽

Yangtze River ◽

Yangtze River Delta ◽

River Delta ◽

The Past ◽

Palynological Study

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The Prevalence of Mild Cognitive Impairment Among the Elderly Population based on Spatio-temporal Data in the Yangtze River Delta Region of China

10.21203/rs.3.rs-579285/v1 ◽

2021 ◽

Author(s):

Luping Shi ◽

Huiping Qiu ◽

Min Zhou ◽

Wei Wang

Keyword(s):

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

Yangtze River ◽

Elderly Population ◽

The Elderly ◽

Yangtze River Delta ◽

River Delta ◽

The Yangtze River ◽

The Past ◽

The Yangtze River Delta

Abstract Background: With the development of China’s economy, China’s aging process has accelerated. The prevalence of mild cognitive impairment (MCI) in the elderly population showed a gradual increase. The Yangtze River Delta Economic Belt plays a very important role in China's economic development. China's seventh national census data show that the aging degree in the Yangtze River Delta is higher than the national average, and the dependency ratio of the elderly population in the Yangtze River Delta also presents the same characteristics. little is known about the prevalence of MCI in the Yangtze River Delta in recent years. It is necessary to summarize and analyze the prevalence and distribution of mild cognitive impairment in the elderly population in the Yangtze River Delta in the past 10 years. This can provide data support for formulating elderly care service policies and is of great significance for promoting healthy aging in China.Methods: By searching the Chinese and English databases to obtain the original research literature on the prevalence of MCI in the elderly population in China. Select the study about the Yangtze River Delta population. Extract relevant data on prevalence in the literature. According to the results of the heterogeneity test, a random-effect model was adopted to estimate the prevalence of MCI, followed by subgroup analyses and meta-regression.Results: A total of 18 articles were included in this study with a total sample size of 33042. In the past decade, the overall prevalence of MCI in the elderly population in the Yangtze River Delta was 18% (95% CI: 15-22%). Spatial distribution results: the prevalence difference between regions was (16%-23%). In the past 10 years, the prevalence of MCI has increased first and then decreased. Analyzed the demographic characteristics, the prevalence of women, low education, old age, rural areas, and no spouse groups was relatively higher. Conclusions: The prevalence of MCI in the Yangtze River Delta region was lower than the national average. There were differences between different regions. Besides, age, gender, and education level were all important factors affecting the prevalence of MCI.

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