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Zhao K.,East China Normal University | Song K.,East China Normal University | Pan Y.,Portland State University | Wang L.,University of Michigan | And 3 more authors.
Ecological Indicators | Year: 2017

Zooplankton in river systems have seldom been studied in the context of metacommunity ecology. Spatial factors (e.g., river connectivity, directionality, and man-made dams) may play a key role in influencing the metacommunity structure of rotifers because of their small body size and weak mobility. In contrast, local environmental factors (e.g., physicochemical habitat) may be more important to crustaceans due to their larger body size and stronger mobility. We sampled zooplankton and environmental factors during wet and dry seasons from 47 sites along the Ying River in China to assess the roles of the spatial and environmental factors in structuring zooplankton metacommunities. We used Moran's eigenvector map and asymmetric eigenvector map to model the influences of river connectivity, directionality, and man-made dams on zooplankton metacommunity structure. We then used partial redundancy analysis to identify individual and interactive effects of spatial and environmental factors on both the entire zooplankton assemblages and two zooplankton groups of different body sizes and mobility. A total of 101 taxa were identified and taxa richness was higher in the wet season (72) than in the dry season (58). Zooplankton assemblages were primarily dominated by rotifers. For the dry season, environmental factors such as total nitrogen, water temperature, and pH explained a significant portion of variation in zooplankton community; river connectivity was more important than river directionality to zooplankton metacommunity structure. For the wet season, spatial factors were more influential than environmental factors such as dissolved oxygen and water transparency; river directionality played an important role in influencing the spatial structures of both environmental condition and zooplankton metacommunity. We also found significant effects of man-made dams on zooplankton metacommunity structure. Spatial factors are more influential in structuring small body size and weak mobility rotifer communities, while environmental factors are more important in determining the variation of crustaceans due to their larger body size and stronger mobility. We concluded that river connectivity and directionality should be considered as key factors for better understanding the spatial processes of planktonic passive dispersers in river networks. Our study provides new insight on understanding riverine zooplankton metacommunity ecology and contributes to the knowledge of river ecosystem health monitoring and management. © 2016

Li W.-L.,East China Normal University | Yu Q.,East China Normal University | Guo X.-Y.,East China Normal University | Da L.J.,East China Normal University | And 2 more authors.
Chinese Journal of Ecology | Year: 2014

To explore successional dynamics of community structure and associated soil response within Pinus massoniana forests, species composition, community structure and habitat properties were determined among three forests differing in restoration stages (i. e., 10, 20-30 and 50 a) in Guniujiang Nature Reserve in Anhui Province, by using a space-for-time substitution approach. The results showed that 1) with the succession, the species richness decreased, but the Shannon diversity index increased. The dominance of deciduous trees declined, but the dominance of evergreen trees progressed in the canopy layer; 2) The distribution of diameter size followed the unimodal type for P. massoniana across the three successional stages, but changed from L to inverse-J type for Castanopsis eyrei through forest succession; evergreen shrubs exhibited good performance in growth; 3) With the forest succession, soil total nitrogen and organic matter contents increased, and soil fertility increased gradually, while the pH value decreased. © 2014, Editorial Board of Chinese Journal of Ecology. All rights reserved.

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.

Shang K.-K.,East China Normal University | Zhang Q.-P.,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 | And 5 more authors.
Landscape and Ecological Engineering | Year: 2014

This paper aims to understand the ecological effects of disturbance on broadleaved evergreen forest in East China. We used a manipulative field experiment approximating the common natural and artificial disturbance types in this area to investigate the community physiognomy, floristic composition, and 5-year recovery dynamics of the post-disturbance forest community. The results indicated that the landscape and forest structure have degraded into shrub communities, structure-damaged evergreen broadleaved communities, and so on. The post-disturbance communities presented different means of plant recruitment and vegetation recovery patterns at an early successional stage. The recovery of disturbed forests primarily depended on external seed sources and re-sprouting from stumps, rather than on soil seed banks, as few buried seeds were found. Re-sprouting thus appears to be key in allowing rapid vegetation recovery in evergreen broadleaved forest. Disturbances seem to be one of the most important factors that can contribute to regional species coexistence across temporal and spatial scales in evergreen broadleaved forests. © 2011 International Consortium of Landscape and Ecological Engineering and Springer.

Sun C.,East China Normal University | Sun C.,Shanghai Key Laboratory for Ecology of Urbanization Process and Eco restoration | Cai Y.-L.,East China Normal University | Cai Y.-L.,Shanghai Key Laboratory for Ecology of Urbanization Process and Eco restoration | And 4 more authors.
Journal of Ecology and Rural Environment | Year: 2010

Leaf expansion and leaf traits of Castanopsis fargesii, including leaf length, leaf width, leaf area, leaf dry mass per unit area and chlorophyll, together with leaf phenology, including timing of leaf emergence, duration of emergence, expansion, and leaf expansion rate, were investigated from the beginning of March to early June of 2008, in the evergreen broad-leaved forest in the Tiantong National Forest Park of Zhejiang, China. It was found that the leaf area increment duration was 34 days; the highest leaf expansion rate 40. 5% • d-1 ; the larger the mature leaf area, the higher the leaf expansion rate ; the specific leaf weight increased in a fluctuant way ; the leaf water content increased in the first phase of leaf development and declined in the late phase ; and the leaf chlorophyll content increased gradually with the leaf area. The correlation analyses of the leaf expansion rate, leaf area and leaf properties show that leaf expansion rate is positively and significantly related to leaf area and chlorophyll content (α =0. 01 ) separately. Leaf area is positively and significantly related to leaf water content and chlorophyll content (o =0. 01 ) separately. Leaf chlorophyll content is also positively and significantly related to leaf water content ( α =0. 01 ).

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.

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.

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.

Li Y.,East China Normal University | Yin X.,East China Normal University | Wei W.,East China Normal University | Yang E.,East China Normal University | And 5 more authors.
Shengtai Xuebao/ Acta Ecologica Sinica | Year: 2010

This article discusses the possibility and mechanism of utilizing a local plant species, Pharammites communis, to control an invasive species Solid ago Canadensis. We monitored specific ecological parameters of the two species in a complete growing season and also measured respectively the specific leaf weight and biomass. To calculate the competitiveness and the aggressiveness between the two species, the de Wit model was applied so as to predict the community succession pattern. We examined the reproduction strategy of the two species based on the comparison of the thousand-seed-weight and seed germination percentage. A seed culture with the tissue extraction of the two plants was conducted to observe the reciprocal allelopathic effect. In these experiments, we collected samples from a set of quadrates established in the construction wastelands in Minhang District located in southwest Shanghai. The experiment has suggested the following major findings. First, in the species mixed communities and at the end of the growing season, the average height, the coverage degree, the density and the important value of the P. communis, which approximated to the results obtained in P. communis mono - community, were all superior to those of S. canadensis. Second, there was no significant difference of the specific leaf weight and biomass per capita of P. communis between the species mixed communities and the P. communis mono-communities, while the two index of S. canadensis in the species mixed communities were significantly lower than those in the S. canadensis mono-communities. Third, the de Wit modelshowed the existence of competition and antagonism between P. communis and S. canadensis in the species mixed communities, and a significant inferiority of S. canadensis in aggressiveness compared to P. communis. The model also implied that P. communis would expel S. canadensis out of the quadrates as their competition progressed. Fourth, the thousand-seed-weight of P. communis was relatively higher than that of S. canadensis in their respective mono - communities, while the germination percentage was lower, which suggested an inferior distribution and reproduction capability of P. communis. And in the species mixed communities, the two data of the two species were significantly higher compared to those in their mono-communities, with a more noteworthy change of S. canadensis, which suggested that it enhanced its distribution and invasive capability more than P. communis does. Finally, S. canadensis extraction exerted an allelopathic effect on itself but imposed no effect on P. communis. Compared to the control group, the germination percentage of S. canadensis was higher at a low S. canadensis extraction concentration (12. 5mg/mL), but it was lower at a higher S. canadensis extraction concentration. On the contrary, S. canadensis extraction of various concentrations exhibited no conspicuous allelopathic effect on P. communis. Based on the observations and results, we conclude that the local plant P. communis has the potential to control and prevent the expansion of the alien invasive plant S. canadensis in our study areas.

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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