scholarly journals MONITORING POPULATION EVOLUTION IN THE PEARL RIVER DELTA FROM 2000 TO 2010

Author(s):  
S. Yu ◽  
F. Liu ◽  
Z. Zhang

On behalf of more populous and developed regions in China, urban agglomerations have become important carries loading active economic activities and generous social benefits, and experienced sharper population increase, which results in great threat on local eco-environment construction. Therefore, exact and detailed population monitoring and analyzing, especially on the long sequence and multi frequency, is of great significance. The nighttime light time-series (NLT) products has been proven to be one of the most useful remotely sensed imagery to acquire persons at 1&amp;thinsp;km&amp;thinsp;&amp;times;&amp;thinsp;1&amp;thinsp;km scales. However, the existed problems, such as light saturation and blooming, greatly limit the accuracy of estimated results. Furthermore, it’s difficult to spatialize population at km<sup>2</sup> level due to the lack of basic data in non-census years. In order to solve all problems mentioned above, the populous Pearl River Delta was selected as the study area. A new residential extent extraction index (REEI) was proposed to solve light saturation and blooming problems. Population spatialization methods in census and non-census years were applied to acquire detailed population distribution from 2000 to 2010. Results showed the feasibility of the proposed methods in this work. During the decade, population was denser in the central PRD and sparser in the eastern, western and northern PRD. The speed of population increase was various in nine cities, but faster in 2000&amp;ndash;2005 than 2005&amp;ndash;2010.

2010 ◽  
Vol 29 (6) ◽  
pp. 35-42
Author(s):  
Jianhua WANG ◽  
Linglong CAO ◽  
Xiaojing WANG ◽  
Xiaoqiang YANG ◽  
Jie YANG ◽  
...  

Wetlands ◽  
2021 ◽  
Vol 41 (4) ◽  
Author(s):  
Xiao-Shan Fang ◽  
Shuang Liu ◽  
Wei-Zhi Chen ◽  
Ren-Zhi Wu

AbstractThe Guangdong Xinhui National Wetland Park (GXNWP) in the Pearl River Delta is an important stopover for migratory birds in China and East Asia. Due to high levels of interference, high sensitivity and fragile environmental constraints, an efficient method to assess the health status of wetland parks such as the GXNWP is urgently needed for sustainable development. In this study, we proposed a habitat-landscape-service (HLS) conceptual model that can be used at the site scale to evaluate health status in terms of habitats, landscapes and services by considering the complex ecosystem of wetland parks. This HLS model included 28 evaluation indicators, and the indicator weights and health-grade divisions were based on expert scores using both the analytic hierarchy process (AHP) and fuzzy comprehension evaluation (FCE) methods. The results showed that the health status of the GXNWP was at the “subhealthy” level, with a membership function of 0.4643. This study found that habitat indicators (0.5715) were the key factors affecting the GXNWP health status, followed by service indicators (0.2856) and landscape indicators (0.1429). The HLS-AHP-FCE method provides a holistic health evaluation indicator system and diagnostic approach for rapidly developing wetland parks in the Pearl River Delta, China.


Water ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 749
Author(s):  
Yuan Gao ◽  
Zini Lai ◽  
Chao Wang ◽  
Haiyan Li ◽  
Yongzhan Mai

Water pollution can be monitored through the use of indicator species, including Brachionus calyciflorus. To do this, it is necessary to understand the species’ population ecology. Four surveys of zooplankton were conducted in May, August, and December 2018 and February 2019 in the Pearl River Delta, China, to examine the population characteristics of B. calyciflorus. The temporal and spatial distribution of abundance, biomass, dominance, and occurrence frequency were compared with those from 2012 to investigate the relationship between changes in the population of B. calyciflorus and environmental factors. The average abundance, dominance, and occurrence of B. calyciflorus in this survey were significantly higher than those of 2012 in all seasons. Principal component analysis showed that environmental factors such as the temperature, transparency, total nitrogen, and total phosphorus of water had a major impact on the abundance of B. calyciflorus. There was a significant positive correlation with transparency, total nitrogen, and total phosphorus of water, and a very significant positive correlation with water temperature. Overall, these results demonstrated that the distribution characteristics of B. calyciflorus can reflect pollution in water bodies and can be used to evaluate water quality. These research results provide a reference for evaluating China’s river health and can help to manage water quality in the Pearl River Delta.


Sign in / Sign up

Export Citation Format

Share Document