Novel urban ecosystems: Concepts, definitions and a strategy to support urban sustainability and resilience

ABSTRACT

The 21st century is already known for unprecedented and fundamental changes and new trajectories--think climate change, global economics, migration and population growth. The world is now predominantly urban and will become increasingly so until mid-century when global population is expected to stabilize at around 70% urban. The world has entered a new geological era, the Anthropocene, in which the impacts and artifacts of humans are recognized as a geologic force. In this "Century of the City." for the world to be sustainable and resilient, cities must be an essential part of the solution--and novel urban ecosystems will play a fundamental role. A new conception, definition, and typology of 21st century "novel" urban nature is proposed here as the basis for a novel urban ecosystem strategy to provide essential ecosystem services to support urban sustainability and resilience. This proposed novel nature strategy is informed by landscape and urban ecology and collaborates systematically in "designed experiments" with urban landscape architecture practice. Designed experiments on novel urban ecosystem are necessary to: 1) monitor the performance of innovative designs to provide essential ecosystem services; 2) to mitigate the inescapable ecosystem disservices; and 3) to build public understanding and support for new types and new models of novel urban ecosystems.

KEY WORDS

Novel Urban Ecosystems; Urban Resilience; Urban Landscapes; Ecosystem Services; Landscape Performance; Adaptive Design

Introduction

Now, still early in the 21st Century, the world faces an uncertain and increasingly challenging future. The global population is projected to increase to 10 billion people by the year 2050, a 43% increase from today's population [1]. For the first time in human history, most of this population increase will occur in the world's cities and urban regions--and the greatest increases in population, and in attendant urban growth, will occur in the developing world [2]. We are now beginning to understand the consequences and complexities of our present, and future, urban existence [3]. The changes that humans have caused are visible from space, measurable in the planet's atmosphere, and palpable to all via the world's changing climate, rising sea levels, biodiversity loss, and changes to water and air quality, human health and the overall quality of life.

The world is undeniably in new and uncharted territory, the era of the Anthropocene--in which the impacts and artifacts of humans have become global in scale, and comparable in its significance to the geologic forces that defined prior eras. In this context, the conventional wisdom that separates and opposes "nature" and "cities" is no longer accurate and certainly not productive to meet current and future challenges. Emma Marris et al. [4] argue that the Anthropocene does not represent the failure of environmentalism, but rather a call-to-action, and a challenge to learn from the "exuberant" and novel urban ecosystems and landscapes that characterize the world's cities--and to develop a more opportunistic and "forward-looking nature."

We know that the future will demand new conceptions, new paradigms and new structures for urban nature--including its appearance, its spatial dimensions, its functions and complexity, and...