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Infrastructure development is central to the processes that abate and produce vulnerabilities in cities. Urban actors, especially those with power and authority, perceive and interpret vulnerability and decide when and how to adapt. When city managers use infrastructure to reduce urban risk in the complex, interconnected city system, new fragilities are introduced because of inherent system feedbacks. We trace the interactions between system dynamics and decision-making processes over 700 years of Mexico City's adaptations to water risks, focusing on the decision cycles of public infrastructure providers (in this case, government authorities). We bring together two lenses in examining this history: robustness-vulnerability trade-offs to explain the evolution of systemic risk dynamics mediated by feedback control, and adaptation pathways to focus on the evolution of decision cycles that motivate significant infrastructure investments. Drawing from historical accounts, archeological evidence, and original research on water, engineering, and cultural history, we examine adaptation pathways of humans settlement, water supply, and flood risk. Mexico City's history reveals insights that expand the theory of coupled infrastructure and lessons salient to contemporary urban risk management: (1) adapting by spatially externalizing risks can backfire: as cities expand, such risks become endogenous; (2) over time, adaptation pathways initiated to address specific risks may begin to intersect, creating complex trade-offs in risk management; and (3) city authorities are agents of risk production: even in the face of new exogenous risks (climate change), acknowledging and managing risks produced endogenously may prove more adaptive. History demonstrates that the very best solutions today may present critical challenges for tomorrow, and that collectively people have far more agency in and influence over the complex systems we live in than is often acknowledged.

Urbanization is the most drastic form of land use change affecting biodiversity and ecosystem functioning and services far beyond the limits of cities. To understand the process of urbanization itself as well as its ecological consequences, it is important to quantify the spatiotemporal patterns of urbanization. Based on historical land use data, we characterize the temporal patterns of Phoenix and Las Vegas – the two fastest growing metropolitan regions in the United States – using landscape pattern metrics at multiple spatial resolutions. Our results showed that the two urban landscapes exhibited strikingly similar temporal patterns of urbanization. During the past several decades, urbanization in the two desert cities resulted in an increasingly faster increase in the patch density, edge density, and structural complexity at both levels of urban land use and the entire landscape. That is, as urbanization continued to unfold, both landscapes became increasingly more diverse in land use, more fragmented in structure, and more complex in shape. The high degree of similarity between the two metropolitan regions may be attributable to their resemblance in the natural environment, the form of population growth, and the stage of urban development. While our results corroborated some theoretical predictions in the literature, they also showed spatiotemporal signatures of urbanization that were different from other cities. Resolving these differences can certainly further our understanding of urban dynamics. Finally, this study suggests that a small set of landscape metrics is able to capture the main spatiotemporal signatures of urbanization, and that the general patterns of urbanization do not seem to be significantly affected by changing grain sizes of land use maps when the spatial extent is fixed. This landscape pattern analysis approach is not only effective for quantifying urbanization patterns, but also for evaluating spatial urban models and investigating ecological effects of urbanization.

This article explores the dimensions of rapid urbanization in the Phoenix Standard Metropolitan Statistical Area (SMSA) over the past thirty years with respect to land use change. We devote primary attention to developing an understanding of what land transformations took place, the extent to which they occurred, and where they occurred. Our findings indicate that 32 percent of the Phoenix SMSA changed between 1970 and 2000. More than half of the overall change was from agriculture to some form of urban land use, and although a large percentage of the region remains open desert the parcels of desert are increasingly fragmented. This has significant implications for urban ecology and biodiversity. The growth indicates that rather than a pattern that reflects the agglomeration effects of a polycentric metropolis, the central business district of the City of Phoenix dominates the region. This has implications with respect to employment patterns, traffic congestion, and urban air quality and climate.

We examined how growth of the Phoenix urban landscape has changed spatial patterns in native Sonoran desert plant diversity. Combining data from the U.S. Census with a probability-based field inventory, we used spatial and multivariate statistics to show how plant diversity across the region is influenced by human actions. Spatial variations in plant diversity among sites were best explained by current and former land use, income, housing age, and elevation. Despite similar average diversity in perennial plant genera between desert and urban sites, numerous imported exotics have significantly increased variation in plant generic composition among urban sites, with a “luxury effect” of higher plant diversity at sites in wealthier neighborhoods. We conclude that controls on natural spatially autocorrelated desert plant diversity are replaced by a variable suite of site-specific human factors and legacy effects, which require an integration of ecology and social science to be fully understood.

In this chapter, we explore the historical dimension of urbanization and why the ecology of urbanization has, until recently, been missing. We discuss the consequences of this for our perceptions of urbanization throughout history and also discuss the emerging reintroduction of ecology and the concept of natural capital into the global discourse on urbanization and sustainability. Humans and the institutions they devise for their governance are often successful at self-organizing to promote their survival in the face of virtually any environment challenge. However, from history we learn that there may often be unanticipated costs to many of these solutions with long-term implications on future societies. For example, increased specialization has led to increased surplus of food and made continuing urban growth possible. But an increased urban - rural disconnection has also led to an alienation of food production from the carrying capacity of the land. While connections and feedbacks with the hinterland that supported growing urban centres were often apparent in the past, this has increasingly been lost in a globalized world. The neglect of a social-ecological perspective and the current disconnect between the urban and the rural risks mean that important feedback mechanisms remain invisible, misinforming policy and action with large consequences for global sustainability. We argue that through reintroducing the social-ecological perspective and the concept of natural capital it is possible to contribute to a redefinition of urban sustainability through making invisible feedbacks and connections visible.

Urban areas are hot spots that drive environmental change at multiple scales. Material demands of production and human consumption alter land use and cover, biodiversity, and hydrosystems locally to regionally, and urban waste discharge affects local to global biogeochemical cycles and climate. For urbanites, however, global environmental changes are swamped by dramatic changes in the local environment. Urban ecology integrates natural and social sciences to study these radically altered local environments and their regional and global effects. Cities themselves present both the problems and solutions to sustainability challenges of an increasingly urbanized world.

The Phoenix metropolitan agglomeration (Fig. 7.1) is one of the fastest-growing conurbations in the United States, and is the focus of the Central Arizona-Phoenix Long-Term Ecological Research Project (CAP LTER) (Grimm et al. 2000, Grimm and Redman 2004). This project has been the locus of significant remote sensing investigation and characterization of the Phoenix urban and peri-urban areas (Stefanov 2002), combined with ground truthing and allied studies (Hope et al. 2003). The information derived from these and other studies is increasingly being used by local governments and regional planners (GP2100 2003). As an example, the City of Scottsdale, Arizona has used high-resolution, airborne, multispectral data to assess impervious and pervious land-cover percentages for surface water runoff studies. This use of remotely sensed information, rather than traditional ground-based surveys, produced estimated cost savings of eight to fifteen million dollars for the city (W. Erickson 1999). Construction of an advanced visualization and modeling environment (a “decision theater”) that integrates remotely sensed and other geospatial data for the Phoenix metropolitan region was completed in 2005 at Arizona State University (J. Fink 2005). Use of such an advanced system enables near real-time modeling of the impact of planning and development decisions. Remotely sensed data acquired at a variety of spatial, spectral, and temporal resolutions provides the basic biophysical information necessary to initialize models of urban resilience and sustainability.

In coming decades, the rapid increase of large cities in the developing world and the transformation of urban landscapes in the developed world will be among the greatest challenges to human welfare and a viable global environment. Although cities occupy only 5% of the Earth’s terrestrial surface, they are home to almost half the global population, who consume 75% of the world’s natural resources and generate an equivalent proportion of pollution and waste. The United Nations estimates that virtually all net population growth over the next 30 years will occur in cities, doubling their population. This anticipated population growth will transform urban landscapes, create undreamed-of challenges and opportunities for political and social institutions, and require an unprecedented investment in infrastructure.

Remote Sensing as a Tool for Urban Planning and Sustainability.- Automatic Land-Cover Classification Derived from High-Resolution IKONOS Satellite Imagery in the Urban Atlantic Forest of Rio de Janeiro, Brazil, by Means of an Object-Oriented Approach.- Advances in Urban Remote Sensing: Examples From Berlin (Germany).- Spatial Analysis of Urban Vegetation Scale and Abundance.- Urban Environmental Monitoring in Buenos Aires - Determining Green Areas.- Challenges in Characterizing and Mitigating Urban Heat Islands - A Role for Integrated Approaches Including Remote Sensing.- Phoenix, Arizona, USA: Applications of Remote Sensing in a Rapidly Urbanizing Desert Region.- Application of Remote Sensing and GIS Technique for Urban Environmental Management and Sustainable Development of Delhi, India.- Berlin (Germany) Urban and Environmental Information System: Application of Remote Sensing for Planning and Governance - Potentials and Problems.- Views of Chiang Mai: The Contributions of Remote-Sensing to Urban Governance and Sustainability.- 20 Years After Reforms: Challenges to Planning and Development in China's City-Regions and Opportunities for Remote Sensing.

Spatial variation in plant diversity has been attributed to heterogeneity in resource availability for many ecosystems. However, urbanization has resulted in entire landscapes that are now occupied by plant communities wholly created by humans, in which diversity may reflect social, economic, and cultural influences in addition to those recognized by traditional ecological theory. Here we use data from a probability-based survey to explore the variation in plant diversity across a large metropolitan area using spatial statistical analyses that incorporate biotic, abiotic, and human variables. Our prediction for the city was that land use, along with distance from urban center, would replace the dominantly geomorphic controls on spatial variation in plant diversity in the surrounding undeveloped Sonoran desert. However, in addition to elevation and current and former land use, family income and housing age best explained the observed variation in plant diversity across the city. We conclude that a functional relationship, which we term the “luxury effect,” may link human resource abundance (wealth) and plant diversity in urban ecosystems. This connection may be influenced by education, institutional control, and culture, and merits further study.

The fate of private lands is widely seen as key to the fate of biodiversity in much of the world. Organizations that work to protect biodiversity on private lands often hope that conservation actions on one piece of land will leverage the actions of surrounding landowners. Few researchers have, however, examined whether protected lands do in fact encourage land conservation nearby or how protected lands affect development in the surrounding landscape. Using spatiotemporal data sets on land cover and land protection for three sites (western North Carolina, central Massachusetts, and central Arizona), we examined whether the existence of a protected area correlates with an increased rate of nearby land conservation or a decreased rate of nearby land development. At all sites, newly protected conservation areas tended to cluster close to preexisting protected areas. This may imply that the geography of contemporary conservation actions is influenced by past decisions on land protection, often made for reasons far removed from concerns about biodiversity. On the other hand, we found no evidence that proximity to protected areas correlates with a reduced rate of nearby land development. Indeed, on two of our three sites the development rate was significantly greater in regions with more protected land. This suggests that each conservation action should be justified and valued largely for what is protected on the targeted land, without much hope of broader conservation leverage effects.

Preliminary assessment of survey and excavation data suggest that major shifts occurred regionally in settlement patterns within El Morro Valley during the last half of the 13th century A.C. Clusters of small masonry pueblos on ridge tops are replaced by a few, large, defensible pueblos; then the valley is abandoned early in the 14th century. Intensification of intercommunity warfare is postulated in attempting to explain these shifts, and our results are compared with those of earlier workers (especially Leslie Spier and Richard Woodbury) to arrive at a tentative cultural-historical outline culminating in Zuni settlement of the Cities of Cibola.

A hidden pitfall in hhtoriography is disregard for the fact that conditions within nations and races change with the change of periods and the passage of time.… This is a sore affliction and is deeply hidden, becoming noticeable only after a long time, so that rarely do more than a few individuah become aware of it.

Every town was contained within a certain economic framework. At local level this implied a system of relationships with the surrounding countryside and the neighbounng towns, within which the town might play a dominant or subordinate role. At national or international levels, it implied systems of relationships, depending on distances within the Mediterranean or even the Greater Mediterranean region. Finally there was political change.