This paper dealt with the Pb contents and Pb isotopic composition of the West Lake Longjing tea. The results showed that in the tea leaves, from young leaf →old leaf →tea limb, the Pb contents tend to increase gradu...This paper dealt with the Pb contents and Pb isotopic composition of the West Lake Longjing tea. The results showed that in the tea leaves, from young leaf →old leaf →tea limb, the Pb contents tend to increase gradu-ally from 1.63 →4.84 →6.07×10-6, wich revealed that the Pb was accumulated gradually in the tea. After cleaned, the Pb contents of tea leaves were significantly reduced. This indicated that the deposits on the surface of tea leaves made a great contributuion to Pb contents. The survey results for soils in the relevant tea gardens showed that soil from the Longjing tea garden has higher Pb contents, with an average level of 49.6×10-6, two times those of common soils (24×10-6) in China. Results of the systematic analysis for tea, tea garden soil and the samples with the relevant background of the Pb isotopic composition displayed that the Pb isotopic ratio of tea is 206Pb/207Pb=1.164±0.005 (2σ). The ratio of 206Pb/207Pb for the soil gradually decreased from residue phase, soil dilute acid extract phase, and then to urban topsoil, i.e., 1.175 →1.171 →1.170. The 208Pb/(206Pb+207Pb) ratios also show a similar variation trend. 206Pb/207Pb ratios in the samples with the relevant background were: vehicle exhaust, 1.124; coal-combustion, 1.156; atmosphere, 1.168; and water, 1.166. Comparative studies have shown that Pb pollution is popular in the environ-mental media (soil, atmosphere, water) in Hangzhou. With the aggravation of Pb pollution, the Pb isotopic composi-tion gradually changed from the natural background (soil residues) to the direction of automobile exhaust. This phe-nomenon could illustrate that the pollution source was the vehicle exhaust, while the coal-combustion contributed little to environmental pollution in Hangzhou. The Pb of the Longjing tea came mostly from soluble phase Pb in the polluted soil. Moreover, secondary pollution was caused by vehicle exhaust.展开更多
From the 1950s to the 1990s,China underwent a significant transformation of its political system and economy,from socialism to rapid development after the reform and opening up.In the 1980s and 1990s,to meet the deman...From the 1950s to the 1990s,China underwent a significant transformation of its political system and economy,from socialism to rapid development after the reform and opening up.In the 1980s and 1990s,to meet the demand for housing and urban modernization under the rapid growth of cities,almost all Chinese cities underwent large-scale urban construction,transformation and expansion.With this background of rapid advancement,many cities have lost their traditional urban features and characteristics.However,it was during this period that Hangzhou not only restored the historical scenery of West Lake through multiple projects but also explored overall planning of the city and introduced conservation ideas,making West Lake,which was originally located outside the city,part of the city.This period also shaped the contemporary urban characteristics of Hangzhou with traditional landscape features.To explore Hangzhou’s positive experience and determine the critical junctures and influencing factors,this study observed the entire historical process using morphological methods.Based on a summary of the characteristics of each development stage,this study further focuses on the key issue of how conservation ideas are gradually introduced into urban planning and affect the development process.展开更多
This article examines the shifting geo-political significance of Hangzhou as presented in two local gazetteers dating from the Southern Song dynasty （1127-1276）. Focusing on literary works quoted in both of these ga...This article examines the shifting geo-political significance of Hangzhou as presented in two local gazetteers dating from the Southern Song dynasty （1127-1276）. Focusing on literary works quoted in both of these gazetteers that describe two of Hangzhou＇s famous halls on West Lake, I argue that geographic discourses on these halls manifest a tension between two conflicting presentations of Hangzhou＇s geo-political significance as understood by literati elite of the Southern Song. In writings concerning the Hall of Possessing Beauty （Youmei tang 有美堂）, Hangzhou was viewed as a city of rising economic and cultural importance during the Northern Song. Writings on the Hall of Centrality and Harmony （Zhonghe tang 中和堂）, in contrast, depict Hangzhou as an imperial refuge for a court in flight and associate it with the motif of territorial loss during the Southern Song when the city became the dynastic capital. By examining how these two views of Hangzhou are contrasted, this essay concludes that gazetteers functioned to grade and rank different kinds of landscapes in order to make geo-political arguments about the proper reconstitution of the empire during the Southern Song.展开更多
基金supported by the geological survey project of China Geological Survey (No.20021400013)the Science Development Fund of Yangtze University
文摘This paper dealt with the Pb contents and Pb isotopic composition of the West Lake Longjing tea. The results showed that in the tea leaves, from young leaf →old leaf →tea limb, the Pb contents tend to increase gradu-ally from 1.63 →4.84 →6.07×10-6, wich revealed that the Pb was accumulated gradually in the tea. After cleaned, the Pb contents of tea leaves were significantly reduced. This indicated that the deposits on the surface of tea leaves made a great contributuion to Pb contents. The survey results for soils in the relevant tea gardens showed that soil from the Longjing tea garden has higher Pb contents, with an average level of 49.6×10-6, two times those of common soils (24×10-6) in China. Results of the systematic analysis for tea, tea garden soil and the samples with the relevant background of the Pb isotopic composition displayed that the Pb isotopic ratio of tea is 206Pb/207Pb=1.164±0.005 (2σ). The ratio of 206Pb/207Pb for the soil gradually decreased from residue phase, soil dilute acid extract phase, and then to urban topsoil, i.e., 1.175 →1.171 →1.170. The 208Pb/(206Pb+207Pb) ratios also show a similar variation trend. 206Pb/207Pb ratios in the samples with the relevant background were: vehicle exhaust, 1.124; coal-combustion, 1.156; atmosphere, 1.168; and water, 1.166. Comparative studies have shown that Pb pollution is popular in the environ-mental media (soil, atmosphere, water) in Hangzhou. With the aggravation of Pb pollution, the Pb isotopic composi-tion gradually changed from the natural background (soil residues) to the direction of automobile exhaust. This phe-nomenon could illustrate that the pollution source was the vehicle exhaust, while the coal-combustion contributed little to environmental pollution in Hangzhou. The Pb of the Longjing tea came mostly from soluble phase Pb in the polluted soil. Moreover, secondary pollution was caused by vehicle exhaust.
基金This article is supported by the National Natural Science Foundation of China(Grant No.2017YFC0702504)and the‘Korea Foundation for Advanced Studies’/‘Chey Institute for Advanced Studies’.The funding funded the data collection of the study.
文摘From the 1950s to the 1990s,China underwent a significant transformation of its political system and economy,from socialism to rapid development after the reform and opening up.In the 1980s and 1990s,to meet the demand for housing and urban modernization under the rapid growth of cities,almost all Chinese cities underwent large-scale urban construction,transformation and expansion.With this background of rapid advancement,many cities have lost their traditional urban features and characteristics.However,it was during this period that Hangzhou not only restored the historical scenery of West Lake through multiple projects but also explored overall planning of the city and introduced conservation ideas,making West Lake,which was originally located outside the city,part of the city.This period also shaped the contemporary urban characteristics of Hangzhou with traditional landscape features.To explore Hangzhou’s positive experience and determine the critical junctures and influencing factors,this study observed the entire historical process using morphological methods.Based on a summary of the characteristics of each development stage,this study further focuses on the key issue of how conservation ideas are gradually introduced into urban planning and affect the development process.
文摘This article examines the shifting geo-political significance of Hangzhou as presented in two local gazetteers dating from the Southern Song dynasty （1127-1276）. Focusing on literary works quoted in both of these gazetteers that describe two of Hangzhou＇s famous halls on West Lake, I argue that geographic discourses on these halls manifest a tension between two conflicting presentations of Hangzhou＇s geo-political significance as understood by literati elite of the Southern Song. In writings concerning the Hall of Possessing Beauty （Youmei tang 有美堂）, Hangzhou was viewed as a city of rising economic and cultural importance during the Northern Song. Writings on the Hall of Centrality and Harmony （Zhonghe tang 中和堂）, in contrast, depict Hangzhou as an imperial refuge for a court in flight and associate it with the motif of territorial loss during the Southern Song when the city became the dynastic capital. By examining how these two views of Hangzhou are contrasted, this essay concludes that gazetteers functioned to grade and rank different kinds of landscapes in order to make geo-political arguments about the proper reconstitution of the empire during the Southern Song.
