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Zhang K.,Shanghai Business School | Ling H.,Fudan University | Da L.,East China Normal University | Da L.,Shanghai Key Laboratory for Ecology of Urbanization Process and Eco restoration
Shengtai Xuebao/ Acta Ecologica Sinica | Year: 2012

Extensive development in Shanghai during the last few decades has led to rapid urbanization. Urban lands have proliferated and the Outer Ring Road, an expressway, cannot stop the expansion and will never be a boundary between urban and rural areas. The Shanghai Green Belt, with its many species and diverse vegetation types, has become a bright spot of Shanghai's urban landscape and is a real attraction for people who desire green space for recreation and relaxation. As Shanghai has grown the aesthetic value of the Green Belt landscape has become more important and its usefulness needs to be re-evaluated to improve construction techniques and landscape management. Many researchers have shown the quality of recreational opportunities and the aesthetic values of urban forests mainly depend on the vegetation type present, the vegetative community components and the structure of the vegetative community, which can be evaluated objectively using a landscape-scale evaluation method. The scenic beauty estimation (SBE) method is based on an analysis of aesthetic trends or people's desire for a landscape. SBE is quite popular and is considered to be the most accurate method of quantifying human desires for landscape-scale management. Typical vegetation types found throughout the year were selected for SBE evaluation. We wanted to elaborate on factors influencing both forest interior and forest edge landscapes of the Shanghai Green Belt, based on an analysis of community types and structural features and to try to answer the following questions: (1) What structural features and seasonal factors have the most influence on forest interior landscapes, and (2) What factors have the most influence on forest edge landscapes and how can scenic values be enhanced through structural optimization and daily management. Seven vegetation types were selected from both forest interior and forest edge areas, in spring, summer, autumn and winter, based on Quantitative Theory I. The influence of community structure and seasonal features on forest interior landscapes and physiognomic features on forest edge landscapes was analyzed using a multivariate regression model between SBE and the measurement of every landscape factor; also relative optimization strategies were considered. The results show: (1) the main factors influencing community structural features are average diameter at breast height (DBH) and variation coefficient of DBH, canopy closure and canopy porosity. In spring, SBE increases with increasing DBH, while in summer, SBE increases with increasing canopy closure. In autumn, communities with smaller DBH variation have higher SBE values in forest interior landscapes. In winter, canopy porosity has the greatest impact on SBE values for forest interior landscapes. (2) The influence of seasonal factors changes from season to season for forest interior landscapes. In spring, communities with some bright color like yellow or purple and communities with moderate bloom have a higher SBE value. In summer, those which have vigorous growth, smaller changes in forest canopy and unobscured trunks increase the SBE value, and some flowering appears to enhance landscape beauty; the SBE value increases with color purity in autumn and the communities with dark bark have the highest SBE value. (3) The physiognomic factors of a community have a significant impact on forest edge landscape scenic beauty, to which the forest canopy line contributes the most, followed by forest edge line. Communities with a slightly undulating canopy line and complex vertical structure and natural edge line have the highest SBE value. Through aesthetic evaluation of different plant communities, we aim to provide a quantitative assessment and prediction for the Shanghai Green Belt and suggest some related strategies for community structure optimization under different conditions, and provide a scientific basis for urban forest planning, design, and management.

Long Q.,East China Normal University | Wang J.,East China Normal University | Da L.,East China Normal University | Da L.,Shanghai Key Laboratory for Ecology of Urbanization Process and Eco restoration
Fresenius Environmental Bulletin | Year: 2013

We divided a 26-year period into six five-year-plan periods in this paper: the "Sixth Five Year Plan" (1985, 6th fyp), "Seventh Five Year Plan" (1986-1990, 7th fyp), "Eighth Five year plan" (1991-1995, 8th fyp), "Ninth Five Year Plan" (1996-2000, 9th fyp), "Tenth Five Year Plan" (2000-2005, 10th fyp) and "Eleventh Five Year Plan" (2006-2010, 11th fyp). Pollution index (PI) and Nemerow's synthetical pollution indexes (P) were used to assess the farmland soil quality. The highest content of Cd, Ni and Hg appeared in the 6th fyp; Cu, Pb, Cr in the 11th fyp; Zn in the 8th fyp; and As in the 7th fyp. The spatial-temporal distribution of the pollution indices for the heavy metals in the farmland soil revealed that Cd, Zn and Hg contributed the most pollution. The higher pollution areas were mainly in the Minhang, Pudong and Jiading districts, which are the closest districts to urban areas. Relatively clean areas were found in Jinshan, Fenxiang and Chongming district, the districts farthest from urban areas. Overall, the P values showed that the pollution trend of the whole Shanghai area was gradually controlled after the 8th fyp. The reduced use of fertilizers, decreased the discharge of industrial waste water, and increasing the disposal rate of waste water and solid waste relieved the impact of agricultural and industrial activities on the temporal variation of farmland soil quality. However, the urbanization process significantly influenced the spatial distribution of the farmland soil quality, especially in districts near urban areas. © by PSP.

Xia T.-Y.,East China Normal University | Wang J.-Y.,East China Normal University | Song K.,East China Normal University | Da L.-J.,East China Normal University | Da L.-J.,Shanghai Key Laboratory for Ecology of Urbanization Process and Eco restoration
Landscape and Ecological Engineering | Year: 2014

Shanghai is the largest commercial and industrial city of China, but air quality issues have hindered its development in becoming a "global city." This study used monitoring data on SO2, NOx, acid rain pH, dustfall, and total suspended particles (TSP) from the Shanghai Environmental Monitoring Center to evaluate and analyze the air quality in urban, suburban, and rural areas during the period 1983-2005. The results showed that the spatial pattern of air parameters was determined by the level of urbanization; thus, the higher the level of urbanization, the worse the air quality. On the whole, the atmospheric environment of the three spatial regions improved gradually because of economical growth and environmental protection since the 1990s. For the entire region of Shanghai, the relationship between the integrated air quality index and gross domestic product (GDP) per capita was an N-shaped environmental Kuznets curve (EKC) due to decreasing air quality in suburban and rural areas this century. Thus, environmental controls should be increased in Shanghai, especially in developing suburban and rural areas during rapid urbanization. © 2011 International Consortium of Landscape and Ecological Engineering and Springer.

Chen X.,East China Normal University | Wang W.,East China Normal University | Liang H.,East China Normal University | Liu X.,East China Normal University | And 2 more authors.
Urban Ecosystems | Year: 2014

Urbanization has resulted in obvious changes in plant species diversity. We analyzed the dynamics of ruderal species diversity in Harbin over the past half century using historical data collected in 1955 and data of the present spatial distribution in 2010-2011. The results show that, the number of ruderal species decreased from 611 to 175 with remarkable tendency of decreasing in perennial species and increasing in winter annual species in the past half century, which caused the shift of life form spectrum from perennial mono-dominant type to summer annual and perennial co-dominant type. Meanwhile, the proportion of tropical originated species increased and the proportion of temperate originated species decreased which were considered to relate with the increase of temperature in urban area during the past half century. Moreover, there was a distinct decrease of the proportion of aquatic and hygrophytic ruderal species while an increase of mesic and xeric ruderal species which suggested a drought trend in urban habitats that consistent with the change of land use characterized as decrease of natural water bodies and wetlands and increase of urban land. Comparison of ruderal species along urbanization gradient also got the similar results with the above results from analysis on temporal scales and confirmed the effect of urbanization on decreasing plant richness. Our results suggested that land use change combined with its effect on temperature and disturbance regimes in urban habitats preferred species with short life span, high drought tolerance, fast growth rates and high seed yields. © 2013 Springer Science+Business Media New York.

Long Q.,East China Normal University | Zhou J.-Z.,East China Normal University | Meng J.,East China Normal University | Da L.-J.,East China Normal University | Da L.-J.,Shanghai Key Laboratory for Ecology of Urbanization Process and Eco restoration
Huanjing Kexue/Environmental Science | Year: 2012

To reveal the magnetic response to atmospheric particulate pollution in tree leaves along urban streets, twenty-four evergreen tree leaves were collected from green belt along Jinshajiang road, Shanghai, which were subjected to magnetic and heavy metals (Zn, Cu, Pb) analyses. The result revealed that in all leaf samples χ, SIRM varied in ranges of (4-59)×10-8 m3·kg-1 and (496-6 114)×10-6 Am2·kg-1, respectively, S-300mT varied from 89% to 98% and χARM/χ<4, χARM/SIRM<30×10-5 mA-1 was found. The magnetic parameters showed that ferromagnetic/ferrimagnetic particles were the main magnetic carriers in dust-loaded tree leaves, and magnetic grains were predominantly pseudo-single domain (PSD) and multidomain (MD) in size. The significant positive correlation between heavy metals (Zn, Cu, Pb) contents and χ, SIRM, χARM, suggested that magnetic parameters like SIRM could be used as a proxy for heavy metal contents. We recommend that Magnolia grandiflora, widely distributed in Shanghai, can be used for particulate pollution monitoring.

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