Challenging Assumptions in Urban Restoration Ecology

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<ul><li><p>Land</p><p>scap</p><p>e Jo</p><p>urna</p><p>l32</p><p>:2IS</p><p>SN 0</p><p>277-</p><p>2426</p><p> 2</p><p>013</p><p> by </p><p>the </p><p>Boa</p><p>rd o</p><p>f Reg</p><p>ents</p><p> of t</p><p>he U</p><p>nive</p><p>rsit</p><p>y of</p><p> Wis</p><p>cons</p><p>in S</p><p>yste</p><p>mChallenging Assumptions in Urban Restoration Ecology</p><p>Joshua Zeunert</p><p>ABSTRACT This paper presents a critical examina-tion of core assumptions of Restoration Ecology (RE) and Urban Restoration Ecology (URE) with a focus on reinstatement of native/indigenous vegetation in urban areas. REs widely utilized and imposed land use approach reconstructs questionable historic interpretations of natural landscapes. RE misappropriates various terms and ideologies central to its paradigm, thereby exclud-ing non- native biodiversity. Despite decades of theory, research, and practice, RE suffers a noteworthy risk of failure. RE applies rural conservation practices to urban environments, which often presents difficulties in terms of scale and suitability for fauna. RE is optimistic or mis-representative regarding economics, maintenance, and risk in urban environments. This paper briefly discusses an alternative focus, which includes a broader concept of restoration. More substantially, this paper explores multi-functional landscape techniques that: respond to novel states in urban environments; that address present and future needs and scenarios; deliver tailored ecosystem services; and provide resources and productivity specifi-cally relevant to urban contexts.</p><p>KEYWORDS Restoration ecology, urban, biodiversity, landscape architecture, indigenous, native, design, plan-ning, management.</p><p>INTRODUCTIONThis paper presents a critical examination of the ideology and practice of Restoration Ecology (RE), also known as ecological restoration/reconstruction/reinstatement, in the landscape context of urbanized Australia. While RE appears to be a reasonable and positive endeavour, there are numerous core problems with its ideology, approach, and eff ectiveness. This paper does not seek to critique the practice of restoring landscapes per se, but rather, questions the prevalence of applying the dominant paradigm and narrow focus in which RE is often conceived and conducted. The critique focuses on RE that returns landscapes to past, historical states (SER 2004; SER 2005; Handel 2011), and the attempts to re- purpose urban and peri- urban landscapes as reconstructed indigenous/native land-scapes in urban areas where these have been altogether destroyed and lost (herein referred to as urban restora-tion ecology or URE). </p><p>While most RE is applied in rural environments or at a regional scale, the majority of discourse does not explicitly diff erentiate between urban and rural contexts. Regardless of context, RE practitioners often apply the same or similar methods in urban and rural areas. While the RE movement provides accessible material on implementation (SER 2005), very little is provided or discussed to its relevance in urban sce-narios. The need for RE in any given context is often treated as a given (Clewell and Aronson 2006) and therefore most literature does not closely examine the context for RE, the where and why. Some RE dis-course blurs the boundary between conservation and restoration, and some misappropriates the term bio-diversity. For the purposes of this paper, native and indigenous are used to denote the plant and animal species occurring in a nation/region before the arrival of humans and/or signifi cant disturbance by humans. </p></li><li><p>232 Landscape Journal 32:2</p><p>Urban refers to an agglomeration of humans in towns, cities, and megalopolises.</p><p>While this paper focuses on an Australian context, it has many coincident themes and parallels with RE in North America, the UK, and worldwide. Urban disciplines aff ected by RE/URE ideology typically include: ecology, urban and regional planning, urban ecology, landscape architecture, urban design, natural resource management, environmental management, architecture, open space management, and horticul-ture. Many of these disciplines have not disseminated critique and debate of URE. As these disciplines often aim to improve and increase natural resources and capital, ecosystem services, and social engagement with cultural and environmental issues and practices, it is, thus, imperative to assess UREs legitimacy in a wider context.</p><p>This article provides a contextual background for ecological restoration cast against a discussion of fl awed assumptions, performance issues, and a suggested paradigm shift to improve landscape outcomes. Possibilities for further research on multi-functional urban landscape approaches are pre-sented, such as urban agriculture at the edges of its scope of considerations.</p><p>BACKGROUNDEons of geological time on earth have given human-ityuntil recent decadesa seemingly endless abun-dance of ecosystem services that have provided us with the fresh water, food, and resources that fund our daily activities. Human practices have always re- shaped and impacted ecosystems, and until recent decades the global human population has not been large enough to cause widespread concern at the collective impacts of human actions. In recent centuries and most markedly, since the 20th century, humans have industrialized at an accelerated pace fueled by extensive use of fossil fuels, natural resources, and ecosystem services to the detriment of biological diversity and native environ-ments. A worldwide urban culture dependent on fossil fuels has generated high pressure on global and na-tional ecosystems, creating concern amongst ecologists, scientists, and in some cases, the wider population. There is an increasing global scientifi c consensus that the Earth has entered a biodiversity extinction crisis (UNEP 2007) due to the cumulative eff ects of human (anthropogenic) impacts on the environment (ABCS </p><p>2010). A wide range of discourse on global and local biodiversity loss has been published. Subsequent focus on reducing further losses has encountered a range of threats and impacts (ABCS 2010; Cocklin and Dibden 2009). In response, conservation of native and indige-nous biodiversity has expanded to include the concepts and practices of restoration ecology/ecosystem res-toration (RE) (Lodwick 1994). Restoring ecosystems and their services is intended as a measure to increase resilience in the face of biodiversity loss and to restore ecosystem services. </p><p>RE as practiced usually attempts to rebuild eco-system services as conservation for conservations sake (DeClerck and Salinas 2011) and/or reconstructs historic landscapes that usually have lesser value to humans. REs increasingly narrow focus on conserv-ing and restoring ecosystems and their services creates a mixed impact in practice. Though primarily based on conservation motives rather than economic or human ends (Redford and Adams 2009), the provision of ecosystem services is an anthropocentric concept. Evaluating the eff ectiveness of reconstructed ecosystem services requires a similarly broad and anthropocen-tric methodology. This article argues that as global populations, ecological footprints, and human impacts continue their unprecedented growth, it is imperative that the landscapes we invest in are fl exible and multi-functional as they:</p><p>1. maximize their benefits to future inhabitants; 2. maximize efficiency and performance; 3. are resilient to future pressures; 4. mitigate impacts of human activities, and5. provide useful resources, services, and benefits </p><p>(WCED 1987).</p><p>This paper does not seek to question the often surprising evidence of native/indigenous biodiversity located in urban areas, but rather to highlight the challenges presented in maintaining or enhancing this biodiversity, especially in areas growing in population, density, and/or intensity of human activity. </p><p>What is Restoration Ecology/Urban Restoration Ecology? In their foundational document (Shackelford etal. 2013, 297), the Society for Ecological Restora-tion (SER) defi ne RE as an intentional activity that </p></li><li><p>Zeunert 233</p><p>initiates or accelerates the recovery of an ecosystem with respect to its health, integrity and sustainability (SER 2004, 1) and the process of assisting the recov-ery of an ecosystem that has been degraded, dam-aged, or destroyed (SER 2004, 3). SERs Guidelines for Developing and Managing Ecological Restoration Projects elaborates:</p><p>Restoration attempts to return an ecosystem to its historic trajectory, i.e. to a state that resembles a known prior state or to another state that could be expected to develop naturally within the bounds of the historic trajectory (2005, 2).</p><p>Hobbs and Norton (1996) state that the goal of ecosystem restoration is to re- transition an ecosystem to its pre- disturbed structure, function, and composi-tion. Initially, RE was primarily focused on rural and regional environments; however, its application in urban environments is increasing. </p><p>REs implementation has been aided by the spatial estimation of indigenous landscape reference ecosystems (low woodland, sedgeland, etc.). In Aus-tralia, seminal works by Benson and Howell (1990) and Kraehenbuehl (1996) mapped pre- European reference ecosystems across the urban regions of Syd-ney and Adelaide and provided detailed species lists, historic photographs, drawings, and accounts. This mapping has provided an understanding of historic vegetation and landscapes in terms of spatial cover-age and vegetation association structures, which has aided REs implementation, especially where reference ecosystems have been destroyed and lost. Assessment of spatial areas, quality, and condition of reference ecosystems is now commonplace and is often an integral component of ecological studies and planning processes. Yet this approach can also be questionable as many of these assessments are highly subjective and involve implicit value judgments (Parkes, Newell, and Cheal 2003). </p><p>The SER guidelines list fi ve contexts for restora-tion, three of which use urban examples where there is no pre- existing indigenous landscape present (SER 2005) in the process of return[ing] ecosystems to their intended trajectory (SER 2004, 12). REs value- laden defi nitions and terms (Suding 2011) refl ect the strong belief that historic, indigenous landscapes are the rightful state.</p><p>To What Extent is Restoration Ecology/Urban Restoration Ecology Utilized?</p><p>We are obviously past any point where strategies that focus on preservation of pristine habitats are sufficient for the job. Greater attention must be placed on human- dominated landscapes (Novacek and Cleland 2001).</p><p>The demand for restoration is rapidly increasing: RE is in a signifi cant growth period and it is becoming a primary focus of natural resource management with thousands, if not millions of restoration projects occur-ring annually across the globe (Suding 2011; Harris 2011). The SER have members and partners in over sixty nations (Whisenant 2011). At a 2010 meeting of the Convention on Biological Diversity, countries com-mitted to a target of restoring 15 percent of degraded ecosystems worldwide by 2020 (SCBD 2010). Growth in RE is evident in the increasing volume of published journal articles and academic programs and outputs. </p><p>Decisions that determine urban land use outcomes involve planners, natural resource managers, landscape architects, architect, environment offi cers, politicians, and various consultants. RE is a prevailing and estab-lished land- use methodology endorsed and imple-mented by many of these professionals (Clewell and Aronson 2006). URE is globally evident in the projects of planners, landscape architects, and architects who increasingly use intensive methods1 in highly urbanized locations2 aimed at increasing indigenous biodiversity (such as vertical green walls on high- density buildings and large road- bridge wildlife crossings) (Francis and Lorimer 2011; Blaustein 2013). </p><p>Why Question Urban Restoration Ecology?While URE appears to be a reasonable and positive endeavour, there are numerous key problems with its ideology, approach, and eff ectiveness. This is espe-cially the case when it is applied with an assumption that RE is an appropriate strategy in any given context. Restoration eff orts frequently ignore the why of the project and imply that restoration is needed, that this is inherently obvious, and that restoration intentions are noble (Clewell and Aronson 2006). The how of restoration needs signifi cantly closer examination and comparison with alternative approaches; a substantial </p></li><li><p>234 Landscape Journal 32:2</p><p>undertaking that is outside of the scope of this paper, but briefl y explored in the fi nal section. </p><p>FLAWED ASSUMPTIONS EMPLOYED IN RESTORATION ECOLOGYREs core problem is that it is retrospective. It assumes that the past provides the blueprint and best solution to current and future issues. Restoring ecosystems to a historical state by reinstating indigenous plant species does not necessarily optimize or maximize outcomes nor make them resilient in the face of pressures of present and future scenarios. Faced with unprecedented changes in climate, land use, and biodiversity, the goal of return-ing to static, past points in time and restarting the eco-logical clock is unrealistic (Moreira 2006; Suding 2011).</p><p>For example, Wade, Gurr, and Wratten claim ecological restoration of farmland can contribute to sustainable agriculture by moving degraded ecosys-tems closer to their former state and thereby restoring ecosystem function (2008, 831). Restoring ecosystem function and historical integrity is a central goal of most RE advocates; however, it is based on several problematic assumptions:</p><p>1. Restoration can restore the lost historic state and/or native/indigenous ecosystem function of sites;</p><p>2. Historic states/ecosystems are optimum for current and future scenarios;</p><p>3. Nature is or was naturally in- balance, and this balance can be (re)constructed by humans; </p><p>4. Systems will recover in the desired way if they are reinstated;</p><p>5. Adaptation, use, or conservation of restored landscapes will be considered appropriate in the future;</p><p>6. RE is the most effective method for restoring degraded land;3 and</p><p>7. Degraded landscapes have less value4 than restored landscapes (accounting for the embodied energy and likelihood of success/failure of RE).</p><p>Lateral thinking may help to develop novel and eff ective solutions to design, plan, and construct relevant ecosystem services, rather than attempting to replicate and reconstruct past landscapes. This is especially relevant in urban contexts.</p><p>Restoration Differs from ConservationREs paradigm and practices are rooted in a rural conservation ethic (Lodwick 1994; Dramstad, Olson, and Forman 1996). While a logical evolution exists between conservation and restoration, problems arise when they are not clearly and explicitly diff erentiated and many RE advocates and literature fall into this misrepresentation. In simple terms, conservation pro-tects areas of remnant native/indigenous biodiversity already in place that have tangible conservation value. Restoration recre...</p></li></ul>