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Yuan L.,East China Normal University | Zhang L.,East China Normal University | Zhang L.,Shanghai Key Laboratory of Urbanization and Ecological Restoration | Xiao D.,East China Normal University | Huang H.,East China Normal University
Estuarine, Coastal and Shelf Science | Year: 2011

Control and eradication of the exotic and invasive plant Spartina alterniflora within the Chongming Dongtan nature reserve, Shanghai, China, is vital for the management and conservation of the saltmarshes. A demonstration project was established using waterlogging and cutting to control this invasive species. Results from 2007 to 2008 showed that, although the managed waterlogging significantly reduced biomass and seed production of S. alterniflora at an early stage, the species subsequently showed rapid adaptation to the long-term waterlogging stress. Thus, managed waterlogging alone was insufficient for the effective eradication of S. alterniflora. However, managed waterlogging for around 3 months, combined with cutting the above-ground part of S. alterniflora at a key stage (flowering period in July), controlled and eradicated the plant successfully. Both the above-ground and below-ground parts of S. alterniflora were killed and the plants began to decompose after 3 months. Furthermore, there was no re-growth of the emergent part of S. alterniflora in the following years. However, once the impounded water was released restoring the natural hydrodynamic regime of the saltmarshes, the seeds and seedlings of S. alterniflora reinvaded the controlled site from the neighboring areas and the S. alterniflora community was re-established. Thus, after eradication of S. alterniflora, control measures should be maintained to prevent the re-establishment of S. alterniflora. The results of this demonstration project indicate a potentially useful and effective approach for the control and management of large-scale invasion by S. alterniflora on saltmarshes in the Yangtze Estuary, China. © 2010 Elsevier Ltd.

Li J.,East China Normal University | Li J.,Shanghai Key Laboratory of Urbanization and Ecological Restoration | Song C.,University of North Carolina at Chapel Hill | Cao L.,East China Normal University | And 3 more authors.
Remote Sensing of Environment | Year: 2011

Urbanization is taking place at an unprecedented rate around the world, particularly in China in the past few decades. One of the key impacts of rapid urbanization on the environment is the effect of urban heat island (UHI). Understanding the effects of landscape pattern on UHI is crucial for improving the ecology and sustainability of cities. This study investigated how landscape composition and configuration would affect UHI in the Shanghai metropolitan region of China, based on the analysis of land surface temperature (LST) in relation to normalized difference vegetation index (NDVI), vegetation fraction (Fv), and percent impervious surface area (ISA). Two Landsat ETM+ images acquired on March 13 and July 2, 2001 were used to estimate LST, Fv, and percent ISA. Landscape metrics were calculated from a high spatial resolution (2.5 × 2.5. m) land-cover/land-use map. Our results have showed that, although there are significant variations in LST at a given fraction of vegetation or impervious surface on a per-pixel basis, NDVI, Fv, and percent ISA are all good predictors of LST on the regional scale. There is a strong negative linear relationship between LST and positive NDVI over the region. Similar but stronger negative linear relationship exists between LST and Fv. Urban vegetation could mitigate the surface UHI better in summer than in early spring. A strong positive relationship exists between mean LST and percent ISA. The residential land is the biggest contributor to UHI, followed by industrial land. Although industrial land has the highest LST, it has limited contribution to the overall surface UHI due to its small spatial extend in Shanghai. Among the residential land-uses, areas with low- to-middle-rise buildings and low vegetation cover have much high temperatures than areas with high-rise buildings or areas with high vegetation cover. A strong correlation between the mean LST and landscape metrics indicates that urban landscape configuration also influences the surface UHI. These findings are helpful for understanding urban ecology as well as land use planning to minimize the potential environmental impacts of urbanization. © 2011 Elsevier Inc.

Tai J.,Shanghai Key Laboratory of Urbanization and Ecological Restoration | Tai J.,Shanghai Environmental Engineering Design Research Institute | Zhang W.,Shanghai Key Laboratory of Urbanization and Ecological Restoration | Che Y.,Shanghai Key Laboratory of Urbanization and Ecological Restoration | Feng D.,Shanghai Environmental Engineering Design Research Institute
Waste Management | Year: 2011

A pilot program focusing on municipal solid waste (MSW) source-separated collection was launched in eight major cities throughout China in 2000. Detailed investigations were carried out and a comprehensive system was constructed to evaluate the effects of the eight-year implementation in those cities. This paper provides an overview of different methods of collection, transportation, and treatment of MSW in the eight cities; as well as making a comparative analysis of MSW source-separated collection in China. Information about the quantity and composition of MSW shows that the characteristics of MSW are similar, which are low calorific value, high moisture content and high proportion of organisms. Differences which exist among the eight cities in municipal solid waste management (MSWM) are presented in this paper. Only Beijing and Shanghai demonstrated a relatively effective result in the implementation of MSW source-separated collection. While the six remaining cities result in poor performance. Considering the current status of MSWM, source-separated collection should be a key priority. Thus, a wider range of cities should participate in this program instead of merely the eight pilot cities. It is evident that an integrated MSWM system is urgently needed. Kitchen waste and recyclables are encouraged to be separated at the source. Stakeholders involved play an important role in MSWM, thus their responsibilities should be clearly identified. Improvement in legislation, coordination mechanisms and public education are problematic issues that need to be addressed. © 2011 Elsevier Ltd.

ZHU L.,East China Normal University | ZHU L.,Shanghai Key Laboratory of Urbanization and Ecological Restoration | ZHUANG Z.,East China Normal University
Mining Science and Technology | Year: 2010

Uncertainty in 3D geological structure models has become a bottleneck that restricts the development and application of 3D geological modeling. In order to solve this problem during periods of accuracy assessment, error detection and dynamic correction in 3D geological structure models, we have reviewed the current situation and development trends in 3D geological modeling. The main context of uncertainty in 3D geological structure models is discussed. Major research issues and a general framework system of uncertainty in 3D geological structure models are proposed. We have described in detail the integration of development practices of 3D geological modeling systems, as well as the implementation process for uncertainty evaluation in 3D geological structure models. This study has laid the basis to build theoretical and methodological systems for accuracy assessment and error correction in 3D geological models and can assist in improving 3D modeling techniques under complex geological conditions. © 2010 China University of Mining and Technology.

Ge Z.,East China Normal University | Cao H.,East China Normal University | Zhang L.,East China Normal University | Zhang L.,Shanghai Key Laboratory of Urbanization and Ecological Restoration
Ecological Engineering | Year: 2013

Spartina alterniflora has been widely introduced to many coastal and estuarine regions of the world as a species for ecological engineering and this species has been spreading rapidly and widely along the Chinese coastline for the past 30 years. Based on four years of field measurements at the Chongming Dongtan wetland in the Yangtze Estuary, a process-based grid model of spatio-temporal range expansion for S. alterniflora was developed. The model incorporated the seasonal patterns of seed bank dynamics, seedling establishment, clonal propagation and vegetative growth, while also considering the effects of hydrodynamic conditions on the range expansion of S. alterniflora in the coastal saltmarshes. Modelling of a survey strip over a single year on the Dongtan wetland showed that the simulated spread pattern agreed with the actual pattern recorded during the growing season (March-September) with an accuracy of 90-95%, based on the estimations of seed bank dynamics and seedling establishment. On a wider spatio-temporal scale, an 8 year simulation showed that the patterns of range expansion of S. alterniflora are amenable to spatially-explicit modelling that takes spatio-temporal processes into account, mainly due to the aggregation effects of clonal integration in patches. Hydrodynamic conditions and niche availability were the most important factors controlling the expansion rate of S. alterniflora on the seaward expansion front. However, the actual expansion rate of S. alterniflora has slowed down in recent years due to the reduction in the sediment load of the Yangtze River following the completion of the Three Gorges Dam Project. There remain several uncertain issues relating to the model setup and its predictive capacity in terms of environmental variability and the stochasticity that is inherent in the modelling of the reproduction, dispersal and survival of S. alterniflora. Furthermore, an update of the model is needed linked to the sediment dynamics seasonality of hydrodynamic conditions in the Yangtze Estuary. In conclusion, this modelling approach provided valuable insights into the life-cycle mechanisms and range expansion processes of S. alterniflora under the current conditions. We suggest the potential application of this model in comparing various control strategies. © 2013 Elsevier B.V.

Li C.,East China Normal University | Li C.,Guangdong Institute of Eco environmental and Soil Sciences | Li J.,East China Normal University | Li J.,Shanghai Key Laboratory of Urbanization and Ecological Restoration | And 2 more authors.
Landscape Ecology | Year: 2013

Urbanization transforms landscape structure and profoundly affects biodiversity and ecological processes. To understand and solve these ecological problems, at least three aspects of spatiotemporal patterns of urbanization need to be quantified: the speed, urban growth modes, and resultant changes in landscape pattern. In this study, we quantified these spatiotemporal patterns of urbanization in the central Yangtze River Delta region, China from 1979 to 2008, based on a hierarchical patch dynamics framework that guided the research design and the analysis with landscape metrics. Our results show that the urbanized area in the study region increased exponentially during the 30 years at the county, prefectural, and regional levels, with increasing speed down the urban hierarchy. Three growth modes-infilling, edge-expanding, and leapfrogging-operated concurrently and their relative dominance shifted over time. As urbanization progressed, patch density and edge density generally increased, and the connectivity of urban patches in terms of the average nearest neighbor distance also increased. While landscape-level structural complexity also tended to increase, the shape of individual patches became increasingly regular. Our results suggest that whether urban landscapes are becoming more homogenous or heterogeneous may be dependent on scale in time and space as well as landscape metrics used. The speed, growth modes, and landscape pattern are related to each other in complicated fashions. This complex relationship can be better understood by conceptualizing urbanization not simply as a dichotomous diffusion-coalescence switching process, but as a spiraling process of shifting dominance among multiple growth modes: the wax and wane of infilling, edge-expansion, and leapfrog across the landscape. © 2013 Springer Science+Business Media Dordrecht.

Niu J.Y.,Shanghai Key Laboratory of Urbanization and Ecological Restoration
Dong wu xue yan jiu = Zoological research / "Dong wu xue yan jiu" bian ji wei yuan hui bian ji | Year: 2011

From December 2009 to May 2010 goose and duck (Anatidae) community censuses in winter and shorebird (Charadriiforms) community censuses in spring were conducted across three types artificial wetlands (urban lake wetland, restorative wetland, abandoned wetland) along the coast of Nanhui, Shanghai. Correlation analyses were undertaken between community indices and habitat factors. The results showed there were significant differences in the density of geese and ducks among the wetlands, but no difference in the number of species. The density of geese and ducks in the restorative wetland was 3.77 times that of abandoned wetland and 6.03 times that of urban lake wetlands. The number of species and density of shorebirds in restorative wetlands was 2.88 and 5.70 times that of abandoned wetlands. We found significant differences in the number and density of shorebird species between restorative and abandoned wetlands. The number of species density of geese and ducks and the Shannon-Wiener (H') index were positively correlated with water area. The number of species and H' were negatively correlated with vegetation area. The number of species, species density and H' and evenness were negatively correlated with vegetation coverage. H' was positively correlated with mean water level. The results showed that the number and density of shorebird species were positively correlated with bare muddy areas. Aquaculture ponds and paddy fields in reclaimed area is efficient sufficient compensation mechanism to maintain more water areas for waterbirds and to control vegetation expansion and maintain shorebird habitat after coastal reclamation.

Wang R.,East China Normal University | Yuan L.,East China Normal University | Zhang L.,East China Normal University | Zhang L.,Shanghai Key Laboratory of Urbanization and Ecological Restoration
Ecological Engineering | Year: 2010

As a species for ecological engineering, Spartina alterniflora was introduced to Chongming Dongtan in 1995, and over the last 10 years, this species has rapidly invaded large areas of the Chongming Dongtan nature reserve. In this study, use of a normalized biomass size-spectra (NBSS) approach was explored to evaluate the possible impacts of S. alterniflora invasion on the benthic communities along gradients of intertidal zones and the invasion history of S. alterniflora within the nature reserve. The results showed that the characteristics of macrobenthic communities and the variation in macrobenthic communities described by the first two CCA axes revealed clearly the gradients of elevation and invasion history of S. alterniflora. The differences in the macrobenthic assemblages between the Spartina alterniflara marshes and the native Phragmites australis marshes decreased with increasing of invasion history of S. alterniflara. The macrobenthic biomass showed a decreasing trend, while the meiobenthic biomass showed a reverse trend along the elevation gradient. The macrobenthic biomass of S. alterniflora marshes with longer invasion history was higher than that at recently invaded S. alterniflora marshes, while the meiobenthic biomass was lower. The slopes of NBSS for the sampling sites showed a trend of steeper slopes with decreasing of elevation and at the recently invaded S. alterniflora marshes than that at marshes with longer invasion history, while the differences between the native P. australis marshes and the S. alterniflora marshes with long invasion history tended to be diminished. The NBSS approach could thus be used more widely to detect possible impacts of S. alterniflara invasion on benthic assemblages. This study also indicated the potential for this approach to provide valuable insights into the ecosystem ecology of invasive species, which could be very important for wetland biodiversity conservation and resource management in the Yangtze River Estuary and other such impacted areas. © 2010 Elsevier B.V. All rights reserved.

Che Y.,Shanghai Key Laboratory of Urbanization and Ecological Restoration | Yang K.,Shanghai Key Laboratory of Urbanization and Ecological Restoration | Chen T.,Shanghai Key Laboratory of Urbanization and Ecological Restoration | Xu Q.,Shanghai Key Laboratory of Urbanization and Ecological Restoration
Ecological Engineering | Year: 2012

Good urban riverfronts have both ecological and social benefits in urban planning and development. With rapid increase of urban stream rehabilitation projects in developing countries, the concept of Public Accessibility of Riverfront (PAR) has become a highlight in evaluating river ecosystem improvement. In this study the Comprehensive Index of Public Accessibility of Riverfront (CIPAR) that consists of 4 sub-indexes and 12 indicators is designed for assessing the conditions of PAR. The index system is novel for its combined consideration of riverfront accessibilities and benefits. These four sub-indexes measure (1) spatial accessibility reflecting riverfront openness and main transportation convenience, (2) visual accessibility reflecting visual field openness, (3) corridor continuity reflecting riverfront vegetation condition, water-oriented settings, and spatial continuity, and (4) amenity reflecting comfortable experience of riverfront environment and diversity of riverfront activities. Based on the questionnaire and field data collected during March 1-15, 2011, 24 reaches of the Suzhou Creek and its distributaries were assessed with CIPAR, and the urban riverfront after rehabilitation was quantified. The result showed that most of the reaches of Suzhou Creek still suffered a poor-fair PAR condition, and that among the four sub-indexes, visual accessibility got the lowest score with an average score of 0.7. The unsatisfactory PAR condition along the Suzhou Creek mainly resulted from the failure in synchronizing the planning and management of riverfront land uses and river channels in previous phase of the rehabilitation project. This case study supports the use of CIPAR to assess the effectiveness of riverfront rehabilitation project. © 2011 Elsevier B.V..

Xiao D.,East China Normal University | Zhang L.,East China Normal University | Zhang L.,Shanghai Key Laboratory of Urbanization and Ecological Restoration | Zhu Z.,East China Normal University
Estuarine, Coastal and Shelf Science | Year: 2010

The range expansion patterns of Spartina alterniflora and the roles which sexual reproduction and asexual propagation play in range expansion were investigated at the Chongming Dongtan nature reserve in the Yangtze Estuary, China. Two range expansion patterns of S. alterniflora at its advancing fronts could be found (1) S. alterniflora-mudflat front (S-M) and (2) S. alterniflora-Scirpus mariqueter-mudflat front (S-S-M). One feature revealed by this study was that a flush of seedling recruitment and establishment in spring was a crucial way for S. alterniflora to colonize new habitats and achieve a fast rate of range expansion. The mean number of seedlings recruited at the S-M front was much higher than that at the S-S-M front. Once established, the survivorship of seedlings was high, both at the S-M and S-S-M fronts. The established seedlings formed new tussocks quickly by vegetative tillering and growth of rhizomes and these finally merged into dense meadows. The mean distance of range expansion of S. alterniflora, after one growing season at the S-M front, was 25.4 ± 3.1 m yr-1 and 2.7 ± 0.5 m yr-1 at the S-S-M front. Sexual reproduction by seedlings and asexual propagation by tillering and growth of rhizomes were the two main means by which S. alterniflora could maintain a fast rate of range expansion on the salt marshes of the Yangtze Estuary. The colonization behaviors of S. alterniflora on advancing fronts differed as a reaction to various external and internal factors. The impact of abiotic and biotic factors governing the range expansion of S. alterniflora and its implications for the spatial structure of tidal wetlands are discussed. © 2010 Elsevier Ltd. All rights reserved.

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