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1. Spatiotemporal Variation of the Land Urbanization Level in Shandong Province during 1990-2020 | |||
WANG Qiuxian,WU Xiao,ZHAO Fen,ZHENG Zijin,LIU Huiling | |||
Earth Science 08 December 2023 | |||
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Abstract:In this paper the expansion process and patterns of urban land in Shandong Province are analyzed from the perspectives of time and space based on the four phases of land use data in 1990, 2000, 2010, and 2020 with the spatial correlation index, hot and cold spot analysis, and the elasticity coefficient of urban land growth. The results show that: (1) In the past three decades, the expansion intensity and expansion speed of urban land in Shandong Province are relatively fast, and the land urbanization has maintained a relatively high growth level. The characteristics of aggregation and dispersion for urban land expansion change over time. The differences of land urbanization level between cities are shrinking, indicating it is of "multi-polar development, decentralized expansion". (2) Qingdao, Jinan and Yantai-Weihai are the core areas of urban land expansion in Shandong Province, but in recent years their central polarizing role has weakened; Weifang, Dezhou and Linyi has become the secondary central areas of urban land expansion and they are developing Faster. The land urbanization pattern in Shandong will take "Jinan - Qingdao - Linyi" as the core in the future.(3) The elasticity coefficient of urban land growth is becoming more and more reasonable on the whole, which shows that the phenomenon of pursuing urban land expansion blindly and ignoring urban population development has been alleviated, but there are still some cities like Binzhou and Linyi where land urbanization grows faster than population urbanization which will lead to the phenomena of empty city. The results of this paper can provide spatiotemporal data support in its healthy expansion of urban land for Shandong Province during its new type of urbanization.……..(10 Points, Times New Roman) | |||
TO cite this article:WANG Qiuxian,WU Xiao,ZHAO Fen, et al. Spatiotemporal Variation of the Land Urbanization Level in Shandong Province during 1990-2020[OL].[ 8 December 2023] http://en.paper.edu.cn/en_releasepaper/content/4761613 |
2. Evaluation of ERA5 temperature and precipitation data in Fujian Province of China. | |||
Amandu Dennis Tagawa,Gao Lu | |||
Earth Science 11 March 2022 | |||
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Abstract:InAlthough reanalysis data has been widely applied over the world in the past two decades, the latest generation reanalysis, ERA5 produced by ECMWF, has not been evaluated on local scales. In this study, monthly air temperature and monthly total precipitation data from 22 meteorological stations in Fujian Province was applied to validate the reliability of ERA5 in 1979-2019. The results showed that ERA5 generally performed well in capturing temporal pattern of temperature and precipitation in Fujian Province of China. The correlation coefficient between observations and ERA5 for temperature ranged from 0.996 to 0.999. The RMSE ranged between 0.36 C and 5.49 C with an average of 1.08 C over all stations. ERA5 monthly minimum temperature, maximum temperature and mean temperatures showed the significant correlations with r2 ranged from 0.87 to 0.89. The correlation coefficient ranged from 0.6 to 0.81 with an average of 0.7 for all the stations which indicates that ERA5 captured well for annual monthly precipitation. The largest RMSE was 625.59mm found at Pucheng station. The biases ranged from -138.8mm to 529.4mm with average bias value of 148.2mm for annual precipitation. The bias difference was possible from the height differences between ERA5 grid point and height of the observation. | |||
TO cite this article:Amandu Dennis Tagawa,Gao Lu. Evaluation of ERA5 temperature and precipitation data in Fujian Province of China.[OL].[11 March 2022] http://en.paper.edu.cn/en_releasepaper/content/4756636 |
3. Analysis on the current situation of land use and economic development in Yantai city | |||
LIU Luyu,WANG Qiuxian,WU Xiao | |||
Earth Science 02 September 2019 | |||
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Abstract:In this paper, based on the remote sensing image of Landsat7 TM/ETM, the ArcGIS10.3 software is used to interpret the land use in Yantai 2015, and the Land Use Remote sensing classification of China\'s coastal zone is classified as the basis, then the land use status of Yaitai 2015 is obtained. The paper analyzes the matching relationship between land use status and economic development by combining the state of economic development, relevant literature and related Yearbook. The following conclusions are drawn: ①The main land utilization type of Yantai 2015 are arable land, woodland, garden and construction sites, while the unused land area is very small. ②The protection of coastal wetlands in Yantai has been better in recent ten years, and the methods of inshore aquaculture and other utilization have increased. ③ The development and policy of Yantai economy is the main driving force of the change of land use mode. ④ The Yantai city belongs to the retarded type of land use benefit, and the development degree of barely coordinating can′t provide a big impetus for economic development. | |||
TO cite this article:LIU Luyu,WANG Qiuxian,WU Xiao. Analysis on the current situation of land use and economic development in Yantai city[OL].[ 2 September 2019] http://en.paper.edu.cn/en_releasepaper/content/4749542 |
4. Analysis on Land Use Dynamic Changes in Qingdao from 2005 to 2015 based on ArcGIS | |||
Zhuotao Liu,Qiuxian Wang,Xiao Wu | |||
Earth Science 30 August 2019 | |||
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Abstract:In order to study the land use change situation of Qingdao in recent 10 years, this paper used the land Use classification system of China\'s coastal zone to overlay the land use of 2015 by visual interpretation with 2005 data in Arcgis10.2. The results showed that the residence of Qingdao increased 1612.3km2, the area of urban mining increased 351.2km2, the area of woodland increased 499.7km2, and the area of arable land decreased 1911.9km2, the grassland areas decreased 342.4km2, and the water body decreased 277.4km2. These changes were mainly due to the speed of urbanization, another reason was that the Government attached importance to environmental issues, vigorously carried out afforestation and returned farmland to forest. The research provided scientific basis for local government departments to formulate targeted land use planning and policies, which is of great practical significance for regional comprehensive, coordinated and sustainable development. | |||
TO cite this article:Zhuotao Liu,Qiuxian Wang,Xiao Wu. Analysis on Land Use Dynamic Changes in Qingdao from 2005 to 2015 based on ArcGIS[OL].[30 August 2019] http://en.paper.edu.cn/en_releasepaper/content/4749450 |
5. Insolation-driven monsoon-mediated changes in Earth's surface processes in mid-latitude East Asia since the last deglaciation | |||
LIU Jianbao,CHEN Qiaomei,XIE Chengling | |||
Earth Science 05 May 2016 | |||
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Abstract:The stability of Earth's critical zone is intimately linked with erosion, chemical weathering and the vegetation type and density, therefore affecting the global biogeochemical processes and in turn the global climate. However, there is a lack of knowledge on how Earth's critical zone processes have changed over time. Here we rebuild erosion-weathering-vegetation interactions since ~14.7 ka using geochemical records of a radiocarbon-dated sediment core from Gonghai Lake in North China. Our results revealed distinct, millennial, late deglacial-Holocene erosion and weathering patterns and transitions. Chemical Index of Alteration (CIA) molar, a humidity proxy, indicated low humidity during the late deglacial ~11.5-14.7 ka, high humidity during the early-mid Holocene ~11.5-3.2 ka, and intermediate humidity during the late Holocene interval since ~3.2 ka. Comparison of our records with other climate reconstructions further suggested an orbital-phased humidity changes in North China. This study provides evidence for the solar-forcing controlled Earth's surface processes in the mid-latitude China under natural climate conditions. | |||
TO cite this article:LIU Jianbao,CHEN Qiaomei,XIE Chengling. Insolation-driven monsoon-mediated changes in Earth's surface processes in mid-latitude East Asia since the last deglaciation[OL].[ 5 May 2016] http://en.paper.edu.cn/en_releasepaper/content/4686394 |
6. Effect of Forest Gaps on the Photosynthetic Physiology of Castanopsis kawakamii seedlings | |||
TANG Rong,HE Zhongsheng,LIU Jinfu,SU Songjin,ZHENG Shiqun,HONG Wei | |||
Earth Science 10 April 2015 | |||
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Abstract:The variations of photosynthetic physiology in plants were the dominant factors that could affected seedlings' dynamic growth. The objective of this study was to explore the effects of weak light on photosynthetic physiology of C.kawakamii seedlings by the measurements of chlorophyll contents, net photosynthetic rate (Pn), and chlorophyll fluorescence in forest gaps and non-gaps. The results showed that: (1) the contents of chlorophyll a (Chl-a), chlorophyll b (Chl-b), and total chlorophyll (total Chl) of C.kawakamii seedlings in forest gaps were lower than those of non-gaps while the value of chlorophyll a/b (Chl-a/b) in forest gaps was higher than that of non-gaps. The increase of Chl-b content improved the absorption of light energy which could conducive to enhance the adaptability of seedlings in non-gaps under the weak light condition, (2) the Pn of C.kawakamii seedlings in forest gaps was higher than those of non-gaps, which showed that the formation of forest gaps could improve seedlings' photosynthetic capacity and promote their growth, and (3) under the weak light condition, the initial fluorescence (Fo) of C. kawakamii seedlings in the low age classes of forest gaps and the high age classes in non-gaps showed an increasing trend. Weak light restrained the seedlings' photochemical efficiency with a downward trend in PSII photochemical conversion efficiency (Fv/Fm) for the low age classes of forest gaps. Photochemical quenching (qP) of C.kawakamii seedlings in forest gaps and non-gaps were sensitive to weak light and demonstrated a decreasing trend. The descending trend of Non-photochemical quenching coefficient (NPQ) for C.kawakamii seedlings in forest gaps was larger than that of non-gaps, which indicated that the decline of heat dissipation capacity constrained the growth of seedlings in forest gaps under the weak light condition. Seedlings in forest gaps could maintain a rapid photosynthetic electron transport rate under the weak light condition. This is due to the actual quantum yield of PSII photochemical (Y) showed a tiny decreasing trend in forest gaps than those of non-gaps. We concluded that weak light condition limited the growth of C.kawakamii seedlings at the low age classes of forest gaps and the high age classes of non-gaps. | |||
TO cite this article:TANG Rong,HE Zhongsheng,LIU Jinfu, et al. Effect of Forest Gaps on the Photosynthetic Physiology of Castanopsis kawakamii seedlings[OL].[10 April 2015] http://en.paper.edu.cn/en_releasepaper/content/4637682 |
7. Sedimentary geochemistry of K02 core from Dahu Swamp: a sensitive record of climate variability in South China during the last 16000yr and its climatic implications | |||
XUE Jibin,ZHONG Wei | |||
Earth Science 07 January 2015 | |||
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Abstract:The late Glacial and Holocene history of Dahu Swamp in South China was reconstructed from K02 core sediment based on dry density, organic and inorganic geochemistry and accumulation rates of the bulk sediment. Multi-proxy data indicate that the late Glacial in Dahu Swamp was punctuated by several cool or cold events, which occurred from ca.16000-15000 cal yr B.P., 14000-13500 cal yr B.P. and 12800-11500 cal yr B.P., respectively, possibly correlated with the Oldest Dryas, Older Dryas and Younger Dryas events discovered in northern high latitude region. Fluctuations of all the proxies indicate that the Holocene climate in Dahu Swamp was actually unstable, and was often interrupted by some abrupt events, such as three relatively cooler events centred at about ca.9800-9400 cal yr B.P., 8800-8000 cal yr B.P. and 7000-6400 cal yr B.P. respectively. From about ca.10000 to 6000 cal yr B.P., multi-proxy data indicate relatively warmer and wetter conditions, which can be considered as the Holocene Optimum in this region, coinciding with the maximum Northern Hemisphere insolation. However, the Holocene Optimum in our study seems to originate at least about 1500 years earlier than that reported previously by other scholars. In addition, an evident dry mid-Holocene interval was revealed by the multi-proxy data as well from about ca.6000-3000cal yr B.P. Our results also provide hints of the paleo-atmospheric circulation changes between the Northern and Southern Hemisphere, especially the seasonal migration of the Intertropical Convergence Zone (ITCZ). It is reasonable to consider the monsoon as a global tropic climate system rather than regional phenomena only and it is necessary to research the monsoon further at the global scale. | |||
TO cite this article:XUE Jibin,ZHONG Wei. Sedimentary geochemistry of K02 core from Dahu Swamp: a sensitive record of climate variability in South China during the last 16000yr and its climatic implications[OL].[ 7 January 2015] http://en.paper.edu.cn/en_releasepaper/content/4627042 |
8. Possible solar control on the historical hydrological variation during the past 500 yrs in Guangdong area, South China: A wavelet approach | |||
XUE Jibin,ZHONG Wei | |||
Earth Science 20 December 2014 | |||
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Abstract:Correlativity between the hydrological variations in the Guangdong area and solar activity reflected by total solar irradiance during the past 500 years was detected using continuous wavelet transform, cross-wavelet and wavelet coherence approaches, as well as pattern matching. Periodicities of ~11 yr and ~32 yr are observed in the flood/drought series coinciding with those known for solar cycles. In-phase relations in shorter timescales and anti-phase relations in longer timescales are identified between flood/drought variations (represented by FDI) and solar activity (represented by TSI), suggesting that the phase is changing over different timescales and the relations are in-phase and anti-phase alternately during different periods. Such a relationship suggests that solar activity is possibly the controlling factor for paleohydrological variations in the Guangdong area. However, the flood/drought variability may be impacted by some other ambiguous factors, which leads to more complicated relations between flood/drought variation and solar activities. | |||
TO cite this article:XUE Jibin,ZHONG Wei. Possible solar control on the historical hydrological variation during the past 500 yrs in Guangdong area, South China: A wavelet approach[OL].[20 December 2014] http://en.paper.edu.cn/en_releasepaper/content/4624682 |
9. Relationship between fossil chironomid and water depth: a tool for reconstructing past hydroclimatic changes in arid Northwestern China | |||
Jianhui Chen,Enlou Zhang,Stephen J Brooks,Xiaozhong Huang,Haipeng Wang,Jianbao Liu,Fahu Chen | |||
Earth Science 03 March 2014 | |||
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Abstract:A significant relationship between the distribution and abundance of chironomids and water depth has long been recognized. However, few studies have been carried out on this topic in arid regions where the chironomid community is usually controlled by water salinity. Thus Bosten Lake, the largest inland freshwater lake (approx. 1200 km2) in China and located in the northwest of the country, provides a unique opportunity to investigate this relationship in an arid region. A total of 42 surface sediment samples, from water depths of 0 m to 17 m, and 12 chironomid taxa were used in the analysis. The first PCA axis explained 59.3% of the variance in the chironomid assemblage and there was a significant correlation between PCA axis 1 scores and water depth (r2 = 0.84, P < 0.001). The chironomid assemblages significantly changed at 8.0 m. This threshold corresponded to an abrupt change in the underwater slopes and the spatial pattern of aquatic vascular plants. RDA showed that the abundance of Chironomus plumosus-type, Microchironomus and Cryptochironomus was positively correlated with water depth, whereas the abundance of Tanytarsus, Polypedilum nubifer-type, Cricotopus and Psectrocladius sordidellus-type was negatively correlated with water depth. These ecological relationships have been supported by the literature. The qualitative chironomid-inferred changes in lake level and qualitative diatom-inferred changes in salinity from a sediment core BSTC001 were also compared. The close agreement in trends of these two variables validates the use of chironomid assemblages to study palaeo-hydrological variability in this westerly-dominated arid region. | |||
TO cite this article:Jianhui Chen,Enlou Zhang,Stephen J Brooks, et al. Relationship between fossil chironomid and water depth: a tool for reconstructing past hydroclimatic changes in arid Northwestern China[OL].[ 3 March 2014] http://en.paper.edu.cn/en_releasepaper/content/4587934 |
10. Moving Trajectory of Urban Heat Island In Beijing, China Based On Gaussian Model | |||
QUAN Jinling,CHEN Yunhao,ZHAN Wenfeng,ZHOU Ji | |||
Earth Science 08 May 2013 | |||
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Abstract:Changing trajectory of urban heat island (UHI) in Beijing from 2004 to 2008 was determined by Gaussian model using daily MODIS/LST data for exploring the general variation of UHI location and distribution characteristics. The results showed that the daytime UHI centroid annually moved along southwest-northeast direction during the period and seasonally varied with a northeast-southwest direction in a large range, while the nighttime UHI in April-June and October-December had a southward trend and that in other months moved along east-west direction near the city core. The spatial characteristics of the summer daytime UHI was primarily correlated with NDVI, while that of the nighttime UHI was mainly related to NIR/SW albedo in 2004-2005, but to NDVI after 2006. Finally, a considerable expanse of UHI was observed in the day of 2007, and a contrast seasonal change of UHI magnitude, extent and volume happened between the day and night. | |||
TO cite this article:QUAN Jinling,CHEN Yunhao,ZHAN Wenfeng, et al. Moving Trajectory of Urban Heat Island In Beijing, China Based On Gaussian Model[OL].[ 8 May 2013] http://en.paper.edu.cn/en_releasepaper/content/4542293 |
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