Junxiang Li

Spatiotemporal pattern of urbanization in Shanghai, China between 1989 and 2005

Quantifying the spatiotemporal pattern of urbanization is necessary to understand urban morphology and its impacts on biodiversity and ecological processes, and thus can provide essential information for improving landscape and urban planning. Recent studies have suggested that, as cities evolve, certain general patterns emerge along the urban–rural gradient although individual cities always differ in details. To help better understand these generalities and idiosyncrasies in urbanization patterns, we analyzed the spatiotemporal dynamics of the Shanghai metropolitan area from 1989 to 2005, based on landscape metrics and remote sensing data. Specifically, the main objectives of our study were to quantitatively characterize the spatiotemporal patterns of urbanization in Shanghai in recent decades, identify possible spatial signatures of different land use types, and test the diffusion coalescence hypotheses of urban growth. We found that, similar to numerous cities around the world reported in previous studies, urbanization increased the diversity, fragmentation, and configurational complexity of the urban landscape of Shanghai. In the same time, however, the urban–rural patterns of several land use types in Shanghai seem unique—quite different from previously reported patterns. For most land use types, each showed a distinctive spatial pattern along a rural–urban transect, as indicated by landscape metrics. Furthermore, the urban expansion of Shanghai exhibited an outward wave-like pattern. Our results suggest that the urbanization of Shanghai followed a complex diffusion–coalescence pattern along the rural–urban transect and in time.

Special Issue on Green Infrastructure for Urban Sustainability

More than 50% of the world population now lives in urban areas, and the urban population is projected to reach 6.3 billion in 2050, most of which will reside in less developed countries (United Nations 2012). Urban green infrastructure as parks, forests, street trees, green roofs, gardens, and cemeteries is especially in an urbanized world of crucial importance as it is the main carrier of ecosystem services and improves the quality of life for urban residents. For instance, it supports regulating ecosystem services by increasing water infiltration (Haase and Nuissl 2007; Pauleit and Duhme 2000) and has positive impacts on the microclimate regulation (Gill et al. 2007; Hamada and Ohta 2010). Furthermore, urban green provides recreational facilities and offers urban residents the possibility to get in touch with nature (Matsuoka and Kaplan 2008) and supports the local food supply through allotment gardens (Barthel et al. 2013). Green infrastructure as a concept has been developed within the last two decades. It commonly refers to the connective matrices of green spaces that can be found in and around urban and urbanfringe landscapes (Mell 2008) or is simply defined as urban and periurban green space systems (Tzoulas et al. 2007). Due to its provision of numerous complementary ecological, economic, and social benefits, green infrastructure not only enables planners to develop multifunctional, innovative, and sustainable places (Mell 2008), but also promotes ecosystem and human health and wellbeing (Tzoulas et al. 2007) and provides abiotic, biotic, and cultural functions to advance and contribute to urban sustainability (Ahern 2007). Urban green infrastructure is closely related to human wellbeing and biodiversity in urban areas (Gaston 2010; Richter and Weiland 2012) and plays an important part in urban ecology. In recent years, in some published books on urban ecology, urban green was factored into investigations regarding how cities and their sociocultural, economic, and environmental systems can be managed in a way that allows producing sustainable cities (Alberti 2008; Endlicher 2011; Gaston 2010; Niemela et al. 2010; Richter andWeiland 2012). However, urban green mostly plays just a minor part when talking about atmospheric processes such as urban heat islands or climate change (Alberti 2008; Endlicher 2011). The studies on urban green infrastructure also focus on human perception, educational values of urban wilderness as part of urban green or social benefits by urban gardening (Richter and Weiland 2012; Endlicher 2011). However, only a few papers have investigated the recreational services in developing countries (Jim and Chen 2006, 2009). In some regional case studies, for instance, designers have paid more attention to implementing theoretical principles and government requirements in urban planning or landscape architecture, but lack technical support from ecological and geographical perspectives (Li et al. 2005; Jim and Chen 2003). Therefore, it is urgently necessary to improve the research scope and methods linking function, ecosystem services, planning, and the design of urban green infrastructure in the pursuit of urban sustainable development (Mao et al. 2012; Chang et al. 2007).

Influence of Park Size and Its Surrounding Urban Landscape Patterns on the Park Cooling Effect

AbstractUrban parks, an essential component of urban green infrastructure, are known for their multiple ecosystem services to the residents in the cities. Mitigating the urban heat island (UHI) effects is one of such services. Scientific understanding on how park size and surrounding landscape pattern influence its cooling effect, however, remains poor. Using 39 parks in Shanghai, China, this paper aims to understand the relationship of land surface temperature (LST) with park size and the impacts of the surrounding landscape patterns on parks’ cooling effect. The results show that the parks’ LST decreased logarithmically with park size. There are nonlinear relationships between park sizes and their cooling effects. Large parks do not have advantages over small ones in the efficiency of cooling the surrounding environment. Both the class and landscape level patterns surrounding the parks influence the cooling effect. The proportion and dominance of urban land use types negatively affect park cooling effec...

Applied urban ecology for sustainable urban environment

Urban ecology is recognized as a well-established science but may need a consolidated theory (Niemela 1999). The classical urban ecological studies are predominantly focused on the bio-physical research of the urban environment and lack addressing its social context and applicability in planning, design and management (Grimm and Redman 2004; Breuste and Qureshi 2011). However, the recent developments in applied urban ecology demonstrate multidisciplinary approaches and application rapidly improving the theoretical foundations of this science (Young 2009; Qureshi et al. 2010). Urban ecosystems still need improved Urban Ecosyst (2013) 16:675–680 DOI 10.1007/s11252-013-0337-9

Impacts of urbanization on vegetation phenology over the past three decades in Shanghai, China

Vegetation phenology manifests the rhythm of annual plant life activities. It has been extensively studied in natural ecosystems. However, major knowledge gaps still exist in understanding the impacts of urbanization on vegetation phenology. This study addresses two questions to fill the knowledge gaps: (1) How does vegetation phenology vary spatially and temporally along a rural-to-urban transect in Shanghai, China, over the past three decades? (2) How do landscape composition and configuration affect those variations of vegetation phenology? To answer these questions, 30 m × 30 m mean vegetation phenology metrics, including the start of growing season (SOS), end of growing season (EOS), and length of growing season (LOS), were derived for urban vegetation using dense stacks of enhanced vegetation index (EVI) time series from images collected by Landsat 5–8 satellites from 1984 to 2015. Landscape pattern metrics were calculated using high spatial resolution aerial photos. We then used Pearson correlation analysis to quantify the associations between phenology patterns and landscape metrics. We found that vegetation in urban centers experienced advances of SOS for 5–10 days and delays of EOS for 5–11 days compared with those located in the surrounding rural areas. Additionally, we observed strong positive correlations between landscape composition (percentage of landscape area) of developed land and LOS of urban vegetation. We also found that the landscape configuration of local land cover types, especially patch density and edge density, was significantly correlated with the spatial patterns of vegetation phenology. These results demonstrate that vegetation phenology in the urban area is significantly different from its rural surroundings. These findings have implications for urban environmental management, ranging from biodiversity protection to public health risk reduction.

Landscape corridors in Shanghai and their importance in urban forest planning.

In the past century people have witnessed rapid rates of urbanization throughout the world. By 2030 it is projected that more than 60% of the world’s population will live in cities (United Nations, 1999). Since the environment of many urban areas is becoming increasingly deteriorated, more attention is being given to making cities healthier, safer, and more sustainable. The role of green space, and urban forests in particular, in achieving these goals is acknowledged by urban planners, managers, and policy makers. Urban forests provide recreational and wildlife habitat and are appreciated for their aesthetic and architectural value. However, they also provide many ecological services to society by reducing the urban heat island, air pollution, noise, energy costs for buildings, and soil erosion. They also store and sequester carbon and perform hydrological functions such as flood control (Miller, 1997). In recent decades, concern about the environmental quality and long-term livability of urban areas has been a driving paradigm for planning professionals (Flores et al., 1998). Recently, the science of green-space planning has conceptually adopted an ecological framework, one that promotes a biologically rich urban environment and interactions among sites across multiple spatial and temporal scales. Ecological principles such as content, context, temporal dynamics, heterogeneity, and hierarchy have been suggested as factors that should be considered in urban green-space planning (Flores et al., 1998). Urban forests are increasingly viewed as living, integral components of urban infrastructure and not simply aesthetic “window dressing” (Miller, 1997; Jim, 1999). This change in appreciation is due to the recognition that trees and other vegetation play important roles in improving conditions in urban environments. While urban forests have many social, ecological, and economic effects, how best to optimize these benefits are among the critical questions that ecologists, planners, decision makers, and practitioners encounter. For instance, when developing new cities, where and how is it best to construct urban forests? To answer these questions is a great challenge and involves integrated study of applied and basic scientific disciplines. The science of landscape ecology has much to offer applied fields such as land-use management, urban planning, and biodiversity conservation, since it deals explicitly with questions of how landscape pattern affects environmental and social processes (Wu, 2001; see also Chapter 2).

Introduction to an Urban Ecosystem Approach

In the context of ongoing urbanization processes and sustainable urban development, the aim is to capture, describe, and convey to various target groups the current significance, the values, and the potentials of urban biodiversity and ecosystem services. To seek sustainable pathways, the current developments and different approaches are to be studied globally, whereas this book focuses on current processes and practices in China and Germany in more detail. The strategic goal is a long-term appreciation of the potentials and increased consideration of urban green spaces as nature-based solutions in city planning and development.

Indicator-based assessment of green space in growing cities as planning tool - experiences from the Sino-German ‘Green Cities Study’

The paper introduce the Sino-German ‘Green Cities Study’. In the last decades China and Germany have experienced a rapid urbanization process caused by rural-urban migration flows, re-densification and population growth. Against this background current developments, different approaches and future challenges in the competition of green spaces and urban land consumption in China and Germany are elaborated, discussed and illustrated within case studies and good practice examples. Mainstreaming urban biodiversity and ecosystem services in urban development policies requires the establishment of adequate indicators and the integration of ecosystem services in planning systems in China and Germany.