The underappreciated value of brownfield sites: motivations and challenges associated with maintaining biodiversity

Abstract

Protection and mitigation of biodiversity are essential within land-use planning; highlighted by the increased importance of nature during the global pandemic and the fight against climate change. Currently, the character of both the land and decision-makers can influence the weight biodiversity is ascribed within planning processes. Through analysis of semi-structured interviews, with various actors within the Northamptonshire planning system, this research explored the opportunities and challenges around promoting biodiversity across brownfield sites; the motivations for conservation by different planning actors; and what this means for the future of urban habitats on previously developed land. This research found that brownfield sites continue to be undervalued for their biodiversity potential, predominantly due to the downplaying of ecological expertise in decision-making. With England’s proposed planning reforms, this paper argues that tensions between brownfield redevelopment and biodiversity conservation stand to be further exacerbated as the government intends to “scythe through red tape” (Johnson 2020b).

Keywords:

• brownfield
• biodiversity
• sustainable development
• planning
• conservation

1. Introduction

Amidst the adversity during the global pandemic of 2020, the United Kingdom’s (UK) Conservative-led government announced that England will “Build Build Build” and build “greener” and “faster” to restore economic growth and social stability as part of “Project Speed”. (UK Prime Minister’s Office 2020a). At the same time, biodiversity thrived during the momentary “anthropause” of the Covid-19 pandemic “lockdowns” (Rutz et al. 2020), where the importance of nature and greenspaces for society and well-being were extolled (Soga et al. 2021). Project Speed threatens severe habitat loss through the withdrawal of discretionary planning processes and stakeholder consultation. Thus, questions regarding “faster” development versus the motivations and challenges associated with maintaining biodiversity arise.

With the view that “the newt-counting delays in our system are a massive drag on the productivity and prosperity of this country” (Johnson 2020b), the government’s White Paper, Planning for the Future proposes to streamline the existing case-by-case assessment of potential development and stop ecological surveys causing delays (Ministry of Housing and Communities and Local Government (MHCLG) 2020). In its place, a three-tiered land zonal system, with categories of Growth, Renewal or Protected areas, will offer developments “permission in principle” with most decisions for approval being made at plan-making stages (29). Table 1 illustrates the key tenets of the proposed planning reform. Such “spatial selectivity” of land into zones is an instrument already employed internationally in planning policy “to emphasise place qualities” (Galland 2012, 1362) with the aim of strengthening economic, environmental, and cultural contexts and their “situational requirements” (Bryson et al. 2016, 121). Despite concerns that biodiversity may lose its protection through the circumvention of ecological surveys, the White Paper suggests that particular areas of high biodiversity value will be allocated as Protected zones in an attempt to create “beautiful places” (Table 1). In theory, the withdrawal of discretionary planning processes and stakeholder consultation will allow planners to protect and improve biodiversity in certain areas with greater ease.

Table 1. Key proposed changes to England’s planning system from the White Paper: Planning for the Future (2020).

Proposed key changes	Details
Zonal planning	Permission in principle once assigned into Growth, Renewal zones and designation of Protected zones where development is restricted.
Consultation process	Takes place at plan-making stages rather than decision-making stages through a digital-first approach.
Streamlining of planning regulation	Local Plans to only include a core set of standards and requirements for development.
A focus on beauty	Commitment to biodiversity net gain with the aim to create “beautiful” places.
Community Infrastructure Levy	A national flat-rate levy in place of Section 106 Developer Contributions.

However, the Wildlife Trusts, a leading UK conservation group, have raised concerns for biodiversity that fall outside of the “neat little boxes” of proposed planning zones believing that new planning proposals will fail to protect nature: “The Government may find it inconvenient that wildlife won’t stick to its three categories and survives outside protected areas, as well as thriving on some brownfield sites that it would like to see developed.” (The Wildlife Trusts, “New planning proposals will fail to protect nature”, 05 August 2021). Within this research, urban brownfield sites are defined as pockets of previously developed land within the fabric of built-up areas, often forming a network of informal greenspaces (Rupprecht et al. 2014), deemed derelict and contaminated (Alker, Roberts, and Smith 2000) but potentially re-developable (The Town and Country Planning (Brownfield Land Register) Regulations 2017, UK, Regulation 4). Urban brownfield areas can maintain particular typologies due to their differing former uses (i.e., as post-factory developments, vacant commercial buildings, plots, and residential properties), making them unique, with potentially ecologically complex, development scenarios (Loures and Vaz 2018; Rega-Brodsky, Nilon, and Warren 2018).

For decades, brownfield redevelopment has been esteemed in planning policy for its sustainable credentials utilising existing urban infrastructures (Urban Task Force 1999; Loures, Panagopoulos, and Burley 2016) to reinvigorate local economic growth and prosperity (Prescott 2005; Siikamaki and Wernstedt 2008). It has encouraged the regeneration of historic industrial regions, such as the Midlands and the north of England (CPRE 2020), and protected the countryside from urban sprawl (Adams, De Sousa, and Tiesdell 2010; Ministry of Housing and Communities and Local Government (MHCLG) 2020). This narrative continues under Project Speed, whereby £400 million of the Brownfield Land Fund has been allocated to building 24,000 homes on previously developed land (UK Prime Minister’s Office 2020b). Arguably, this “sustainable” label has three major flaws: first, insufficiency of available urban brownfield areas to meet UK housing supply demands (Heid 2004); second, the unequal effects of remediation and gentrification on minority communities (Melstrom and Mohammadi 2021); third and importantly for this research, the decline of national biodiversity in relation to brownfield redevelopment (Hayhow et al. 2019). The often derelict and unmanaged character of previously developed areas can make urban brownfields host to rich flora and fauna, with rapid colonisation and establishment of native plant species (Meffert and Dziock 2012; Schröder and Kiehl 2020) and succession toward urban woodlands (Kowarik and Langer 2005; Trentanovi et al. 2021a). These successional stages attract and support diverse, stress-tolerant, and even rare native species, especially protected invertebrate species such as bumblebees (e.g., Shrill carder bee) and butterflies (e.g., Small blue butterflies), making urban brownfield sites unique for the ecological diversity and connectivity of inner-city nature (Mathey et al. 2015; Threlfall and Kendal 2018). Brownfield sites are often categorised as open mosaic habitats (Eyre, Luff, and Woodward 2003; Riding et al. 2010; Rupprecht et al. 2014) and are specifically classified within the UK Biodiversity Action Plan (BRIG 2011) due to greater biodiversity than managed/planted greenfield spaces, i.e., land not previously developed, but characterised by controlled vegetation such as agricultural fields and recreational parks (Kowarik 2011; Bonthoux et al. 2014; Goulson et al. 2015). The diversity and rarity of some brownfield sites, which may only have existed for a few decades, are comparable to the value of some ancient woodland sites where trees have taken hundreds of years to mature (Barker 2015). Despite this, the extraordinary existence and character of such habitats is not widely recognised or understood outside of the scientific community. Brownfields are at significant risk of removal by development due to perceptions of being “wastelands” (Bonthoux et al. 2014; Mathey et al. 2018). This calls into question the ability of planners to confidently consider the value of biodiversity across urban brownfield areas in the wake of England’s planning reforms.

Focusing on the motivations associated with conserving biodiversity by actors in the planning system should aid in understanding the potential for fairness and transparency toward the value of nature within the urban brownfield planning system. Under a constructivist logic, which assumes that people’s realities are constructed based on a shared foundation of experience and values (Williamson 2006), it is reasonable to assume that different actors within the planning system with varying objectives and agendas will likely approach conservation and perceive the benefits and challenges of brownfield sites through different lenses (Blaikie 2011). This research, therefore, explores the opinions and experiences of ecologists and conservation practitioners, local authority planners, a surveyor, and planning consultants to answer two key objectives in preview of the proposed planning reform:

1. How are different stakeholders currently motivated to conserve biodiversity in development planning?

2. What are the implications for biodiversity in planning and development with reference to urban brownfield sites?

2. Location of study: Northamptonshire

Łopucki and Kitowski (2017) believe that previous research (Donovan, Sadler, and Bryson 2005; Lorimer 2008), which tended to focus on biodiversity impacts of urbanisation across large towns or cities, has led to extensive, large-scale generalisations being applied within less applicable regions. Therefore, this study focuses on Northamptonshire, a mainly rural middle England county (2364 km²) with a patchwork of small urban centres, and a population of 747,622 people (Northamptonshire County Council 2019). At the time of this research, 89 brownfield sites were within or on the edge of built-up areas in Northamptonshire. Their use and scale ranged from individual garages to school sites, car parks, and large industrial buildings. In comparison, the city of Birmingham had over 1,000 brownfield sites registered. The variability in house prices and accessibility to the economic centres of London and Birmingham via two main railway routes make Northamptonshire an attractive location for commuters, resulting in a housing delivery target of at least 70,000 houses by 2031 (West Northamptonshire Joint Planning Unit (WNJPU) 2011; North Northamptonshire Joint Planning and Delivery Unit (NNJPDU) 2018). In light of England’s planning system transformation, this analysis opens a timely discussion surrounding existing attitudes toward the conservation of urban biodiversity in development planning. Rigorous research on this scale aims to provide insight into “an early introduction of measures” that could help to preserve the biodiversity within areas of more premature urbanisation (Łopucki and Kitowski 2017, 934).

3. Method

Semi-structured online interviews were conducted with principal biodiversity actors involved in development planning within Northamptonshire between June and August 2020. District and borough council websites, planning and environmental statements, and ecological surveys were reviewed prior to the interviews to provide context and background knowledge regarding how biodiversity was considered in Northamptonshire with regard to a) the justification for development; b) biodiversity assessment prior to construction; c) the proposed biodiversity mitigation strategies. Respondents were recruited strategically from three distinct stakeholder categories via recommendations and networking. This included:

• three local authority (LA) planners;

• five consultants: one chartered surveyor from a small family-owned development company and four planning consultants working on behalf of larger development consultancy firms. This broadened the pool of experience as opposed to speaking to individual developers;

• four experts representing the scientific community: two ecologists and two conservation practitioners from separate Northamptonshire wildlife organisations.

Data collected from the interviews was coded in line with Richards’ three stages of analysis: descriptive, topic, and analytical (Richards 2015, 107). Topic coding of the interview transcriptions identified recurrent themes and the analytical coding grouped concepts and categories together to enable conclusions to be drawn. Ethics approval for this research was given by the PG Research Ethics Committee, School of Geographical Sciences, The University of Bristol.

4. Results and discussion

With the goal of evaluating brownfield sites as opportunities or challenges to future sustainable development, the review of planning documents and the interviewee responses revealed ubiquitous agreement that biodiversity conservation is just one aspect of a complex decision-making system within development planning. The findings are structured to reflect the multifaceted context in which biodiversity is considered through investigation of Objectives 1 and 2.

4.1. Objective 1: How are different stakeholders currently motivated to conserve biodiversity in development planning?

All respondents acknowledged the responsibility of new developments to meet sustainable development targets in line with England’s National Planning Policy Framework’s (NPPF) three—pronged definition, including social, economic, and environmental imperatives (MHCLG 2021) (Table 2). All cited the need for new developments to address the nation’s growing population, inward migration, and changing household composition. The NPPF outlines requirements to support the growth of urban communities including the “provision of infrastructure” and support for “innovation and improved productivity” (MHCLG 2021, 5). The respondents corroborated the provision of public transport services and opportunities for job creation as important considerations for “sustainable urban extensions.”

Table 2. Benefits and challenges of development on brownfield sites in relation to sustainable development.

Sustainable Development	Comments	Local Authority Planners			Consultants (Work For Developers)					Scientists
					Planning Consultants				Surveyor	Ecologists		Conservationists
		A	B	C	A	B	C	D	A	A	B	A	B
Social	“Abandoned”, “redundant”, “derelict”, “neglected”, “unsightly”, “unloved”, “scrubby”, “tatty” areas “non-conforming uses”, ”wrack and ruin”	✓	✓	✓			✓	✓	✓				✓
	Identified to meet the needs for housing and development	✓			✓					✓
	More accepted for development by public and government		✓	✓		✓				✓	✓	✓	✓
	Constraints to development, i.e., heritage, building regulations	✓	✓	✓		✓
	Potential for high density development				✓		✓		✓
Economic	Makes use of existing infrastructure and local facilities in an urban location	✓	✓	✓		✓							✓
	Regeneration of urban centres			✓
	Contamination, remediation	✓		✓	✓	✓	✓	✓	✓			✓	✓
	Cost, threats to viability	✓	✓		✓	✓	✓	✓	✓				✓
	Unpredictable, unknowns	✓			✓		✓	✓
Environmental	Removes pressure off greenfield land	✓	✓	✓				✓	✓				✓
	May not support biodiversity, low consideration compared to greenfield				✓	✓		✓		✓
	“May provide habitats”,” be rich”, “alive”, “buzzing” with wildlife, “variable”	✓	✓		✓	✓				✓	✓	✓	✓

Acceptance of the need for development was combined with apprehension surrounding its placement and delivery, and views varied between the stakeholders. Planning Consultant B cited biodiversity removal as a common objection to greenfield development by local communities and considered brownfield redevelopment as an opportunity to protect greenfield sites despite the additional remediation costs due to historic contamination. This brownfield-first narrative was further supported by the popular assumptions that brownfield sites make effective use of existing infrastructure and local facilities, and improve the aesthetics of “tatty” (Surveyor A) and “redundant” (LA Planner C) areas (Table 2). Such viewpoints reflect the national political narrative, as Consultant B recognised that local governments employ brownfield redevelopment as a political token to appeal to constituent voters. LA Planner B confirmed this rhetoric: “Obviously building on brownfield means that you might not necessarily be building on greenfield so the priority from the government is to use previously developed land.”

Despite the opportunities of building on brownfield sites, the obligation to provide housing cannot always be satiated by a collection of brownfield developments. LA Planner A attested tradeoffs must be made between conserving biodiversity and building houses for future generations. Where development needs take precedence, the challenge for planners and consultants is to efficiently compensate for the loss of the natural environment through sensitive, sustainable design, LA Planner C: “we have a duty to provide housing, so the art is to make sure that the development includes sustainability elements and…elements that encourage biodiversity.” This statement emphasises the holistic approach to sustainable development by LA planners (Table 2). However, “sustainable” had different emphases for different people, with Ecologist A questioning: “Well, what do you mean by sustainable?” Table 2 highlights the importance of the social and environmental pillars for scientists. Most LA planners and consultants agreed that incorporating biodiversity conservation into sustainable planning was considered just “another piece of the jigsaw” (Consultant C) as respondents also cited improved air quality, opportunities for jobs, and sustainable construction as key considerations. LA Planner C put the challenge of balancing sustainability and biodiversity into context: “Do we keep all the trees? But then will the tree overshadow a building that will then have to turn more lights on? …You do one thing and it’ll have implications on other things.” The reviewed planning documents highlighted how sites circumvented the complexities of sustainable development via biodiversity offsetting and enhancement, for example, through the addition of bat boxes, provision of new hedgerows, and wildlife tunnels for badgers.

All respondents confirmed how biodiversity offsetting is often focused on brownfield sites due to negative public perceptions compounded by a lack of public access, Conservationist A: “[Brownfields] are also places people don’t have a lot of access to … they’re not often places you’d encourage your children to play. Whereas greenfield is much more positive, even though a lot of brownfield sites are much more biodiverse than some greenfield sites.” Ecologist B believed that a lack of scientific awareness and an “oversimplification” of brownfield site biodiversity favoured development opportunities in the eyes of the general public and, therefore, were an “easy strapline” for the government to promote. As seen in Table 2, the scientific stakeholders (ecologists and conservationists) found brownfield sites potentially more attractive conservation zones than the other planning actors: Ecologist A: “You get some lovely bits of greenfield countryside; you know a nice chalk downland. But…managed wheat fields, with hedges flailed to within an inch of their life…biological deserts. I think it’s quite an insidious term really [“greenfield”], it bundles so much good and bad into one.” They vocalised the high value potential of brownfield habitats as “low-nutrient systems” (Conservationist A) able to support “stress-tolerating species” (Ecologist A). LA planners and consultants commonly cited badgers, bats, birds, and newts, renowned species considered in planning processes, with only Consultant B referring to a brownfield site bird species, the Black Redstart. This disparity reflected individual ecological knowledge and highlighted the variation of respondents’ experience of brownfield redevelopments with the suggested “oversimplification” of the variability of biodiversity across different landscapes. Respondents’ experiences and motivations to conserve biodiversity varied with the potential to influence mitigation levels.

The moral obligation to conserve biodiversity for its ability to thrive irrespective of human modification was recognised by all respondents. However, the extent to which this motivation drove planning decisions varied between respondent groups. Conservationist B found issue with the identification of biodiversity as “species-poor” and “species-rich” as commonly classified in ecological planning surveys, and argued that biodiversity exists outside of human valuation, with the need for development designs to make more of existing natural features. In contrast, Ecologist B stated pragmatism is needed within development planning, “what you don’t want to fall into is…becoming precious about every last bit”. Hence, there are clear policies in place to protect key species, however, for some, this was still an inconvenience. When referring to the statutory obligation to protect great crested newts, the consultants expressed the hassle of safeguarding their survival, “You can’t dispose of them in the quietness of night…because that’s illegal. You have to take account of them, either through moving them to somewhere else or safeguarding their existing location”, and mitigation in relation to development viability, “they can reduce the capacity of sites for accommodating development.”

For the consultants who work for developers, practicality and commercial viability stood in the way of conserving biodiversity based upon moral obligation. Surveyor A stated, “we try our best” but recognised biodiversity mitigation as a significant “cost line”. With developer contributions toward affordable housing and highway maintenance, conservation of biodiversity can be a risk to the overall validity of development, further emphasising the importance of economic aspects to the consultants (Table 2). Managing costs was a particular concern for development on previously developed land as opposed to the development of greenfield areas which was likened to building on a “blank canvas” (Conservationist B) and “a clean slate” (Consultant B). Brownfield redevelopment often requires additional remediation costs to remove historic contamination, further threatening the extent of biodiversity mitigation (Table 2). Highlighting financial pressures, Conservationist B and Consultant A stated that, despite policy requirements, developers are largely motivated to achieve the minimum requirements for conserving biodiversity to increase development profitability. The current system corroborates a market-centred approach to development, i.e., “selling a product” to developers whereby ecological expertise (often “a bit of an inconvenience” (Ecologist B)) is expected to “superimpose” (Ecologist A) recommendations onto predetermined designs resulting in compromises over ecological suggestions. Three respondents referred to this approach to ecological assessment as a “tick box exercise” suggesting that essential biodiversity assessments can fall short of rigorous application: “biodiversity is literally a tick box exercise and the presence of a report is sufficient… Sometimes you have the feeling that the report hasn’t been read.” (Ecologist A). Consultant B inferred that for biodiversity to be given greater consideration in development planning it requires being framed as a “marketing tool”. LA planners all referenced the benefits of nature for human well-being: ranging from greenspaces for exercise, gardens for interactions with wildlife, to the global contribution toward fighting climate change. Consultant C emphasised the increased importance of including local greenspaces within new developments following the COVID-19 restrictions where people were confined to just one hour of outdoor exercise a day (Johnson 2020a). The increased safeguarding of biodiversity has the potential for “a win-win” scenario (Conservationist B) whereby considered conservational development planning is also instrumental to human well-being.

Planning consultants referred to the recent introduction of the biodiversity net gain (BNG) strategy as the ultimate incentive for future biodiversity-related mitigation approaches in development planning. Conservationist A suggested that the BNG strategy tool would align actors with a shared environmental goal: “it gives people who aren’t so excited about biodiversity a way of understanding the pros and cons ‘cause it comes out with a number…so it makes it more accessible for lots of different people.” however, “[BNG] is not a replacement for having a good ecologist.” Conservationist B was skeptical whether biodiversity policy always translated into diligent development practice: “I think you can’t go wrong with the BNG. But it is how it’s managed …the interpretation of a lot of these regulations is down to the individual planners.” However, despite arguments to better encourage ecological input into development planning, Conservationist B warned that ecologists too could be compromised: “the ecologist, whilst they should be a professional…they are paid for by the developer who wants a certain amount done.” Such responses suggest that experienced ecologists, as actors within the planning system, have considerable command over the future of biodiversity but are restricted in unlocking their capabilities whilst answerable to developers. As a resolution, Consultant A proposed that all actors must engage in a collective conversation to bring together their opposite intentions and work toward a shared goal: “we need to be conscientiously bringing forward development that isn’t just maximizing profits, it’s actually looking at a broader definition of profit”. Ecologist B agreed, “there’s no reason why biodiversity can’t go hand-in-hand ….with landscape design. There’s a lot of overlap…but we do need everybody collectively buying into it”.

4.2. Objective 2: What are the implications for biodiversity in planning and development with reference to urban brownfield sites?

Within the literature (Table 3), the value of nature has been classified into intrinsic (nature as an end in itself), instrumental (nature as merely a means to an end) and relational motivations (the meaningful relationships between humans and nature) (Arias-Arévalo, Martín-López, and Gómez-Baggethun 2017). Nature can thrive in areas of minimal disruption from extensive human activity such as urban brownfield sites and their varying successional stages have been considered “surrogate habitat for high intensity pastures” (Habel et al. 2019, 5). The very nature of brownfield sites underpins the intrinsic motivation for conservation simply by existing outside of areas of frequent human modification and provides the impetus for protection strategies such as the UK Post-2010 Biodiversity Framework (Table 3). The value given to biodiversity across brownfield sites expressed by the scientific players in this study aligned with an intrinsic and moral care for nature. Whilst appreciative of brownfield biodiversity, consultants, who work closely with developers, were cautious of conservational practices based on intrinsic value alone, believing it lacks real-world application (Table 3), citing remediation costs and unexpected contamination issues as potential barriers to conservation (Table 2).

Table 3. Motivations for conserving biodiversity.

Motivation	Key points	Key literature
Intrinsic	The moral obligation to protect nature.	(Soulé 1985; Oksanen 1997; Maguire and Justus 2008; Laycock et al. 2011; Joint Nature Conservation Committee and Department for the Environment and Food and Rural Affairs (JNCC and DEFRA)) 2012; O’Connor and Kenter 2019).
	Impetus for UK environmental protection strategies.
	Can exclude the needs of society in favour of the rights of biodiversity.
	Absence of real-world application.
Instrumental	Ecosystem services and benefit to sustainable design.	(McCauley 2006; Justus et al. 2009; Niemelä et al. 2010; Gómez-Baggethun and Ruiz-Pérez 2011; Reyers et al. 2012; Pedersen 2012; Rode et al. 2016; Chiaradia, Sieh, and Plimmer 2017; Moilanen and Kotiaho 2018; Björnberg 2020).
	Putting a price on conservation.
	Polluter pays principle; commission of surveys and mitigation licensing.
	Steward earns principle; brownfield regeneration funding. Motivates the conservational practice of biodiversity offsetting.
Relational	The plurality of relations and benefits that connect all life on earth.	(Healey 2000; Stokes et al. 2010; Tallis and Lubchenco 2014; Chan et al. 2016; Díaz et al. 2018; Himes and Muraca 2018; Casas et al. 2021; Trentanovi et al. 2021b).
	Relationality in planning and architectural design. Giving conservational agency to the general public through education.
	Inclusivity of under-represented groups in conservational decisions.
Plural valuation	Obtaining a comprehensive understanding of how people are motivated to conserve nature and the origins of their decisions.	(Dearborn and Kark 2010; Couix and Hazard 2013; Arias-Arévalo, Martín-López, and Gómez-Baggethun 2017; Berry et al. 2018; Bruskotter et al. 2019).

Such arguments have underpinned the values debate (Table 3) resulting in conservational practices such as biodiversity offsetting to temper project and budget constraints, alongside pressures to provide housing and economic growth. Biodiversity offsetting, a market-based instrument, reconciles economic motives with biodiversity conservation by compensating biodiversity loss via improvements elsewhere, i.e., Protected zones as in Table 1. Under the government’s recent rhetoric to “build back greener”, with a biodiversity net gain strategy, the offsetting practice is seen by LA planners and consultants in this study as a means to meet both housing supply demands and conservational targets (Johnson 2020b). Investing in the enhancement and mitigation of development impacts on biodiversity, via an ecosystem services approach, could prove instrumental to human well-being, with cultural benefits such as improved landscape aesthetics and entertainment, and regulating services like pollination and pest control (La Notte et al. 2017; Marselle et al. 2021). “Buying into conservation” (Justus et al. 2009) in this way has motivated some developers to go beyond minimum requirements for conservation to fit into an “environmentally-aware” niche in the market (Dixon 2007, 2395). For planning actors, this is a practical and sustainable way to balance the competing considerations of planning processes.

However, removing the ethical regulation of intrinsic values in conservation through biodiversity offsetting can lead to an irreversible net loss when comparing the quick temporal frames of human activity against naturally slow-moving biodiversity succession within some brownfield sites (Moreno-Mateos et al. 2015; Taherzadeh and Howley 2018). This current conservational practice raises concern amongst wildlife conservation groups both within and outside of this research in the context of the government’s “Project Speed,” where the key proposed planning changes are outlined in Table 1. An online statement by the Director of the Royal Society for the Protection of Birds (RSPB) posited that together with early consultation processes the zonal designation of land into Growth and Renewal development areas would create a significant and irreversible loss of opportunity to value and defend a succession of brownfield biodiversity (“Which future do we want to plan for?” RSPB, 7 August 2020). Does Project Speed continue McCauley’s (2006) belief that we are “selling out on nature”?

Further, the ecosystem services approach which assigns value to particular ecological systems and structures still perpetuates tradeoffs (Paavola and Hubacek 2013). Concerns over what constitutes biodiversity in the proposed BNG metric implies that developers may well employ the ecosystem services approach in order to practically achieve the 10% net gain target (Department for the Environment and Food and Rural Affairs (DEFRA) 2019; Turkelboom et al. 2018). Whilst brownfield sites are perceived as “unsightly” (Planner A), their low aesthetic value will continue to correlate to high development potential and loss of brownfield biodiversity (Brady 2006). This fate is underlined by the government’s future commitment to “the creation of beautiful places” (Ministry of Housing and Communities and Local Government (MHCLG) 2020, 21; Table 1) and brownfield redevelopment: “we are going to build fantastic new homes on brownfield sites and other areas that with better transport and other infrastructure could frankly be suitable and right for development” (Johnson 2020b). A danger of the UK government utilising brownfield regeneration as a tool to sell development to the public is its recent promise to simplify planning regulations and “scythe through red tape” (Johnson 2020b). The removal of the “newt-counting delays” (Johnson 2020b) could result in species endangerment. The conservationists within this study felt that future efforts to follow the proposed BNG strategy could be disingenuous and allow the justification of habitat destruction and tradability through the loop hole of offsetting; a fear shared with global conservation actors and coined as the “license to trash” (Trémolet et al. 2021, 19). Despite the legislative protection of the UK Biodiversity Action Plan, reliance on the market-driven nature of development, particularly in the backdrop of Project Speed, could continue to overlook the cultural and ecological value and variability of brownfield sites to the detriment of threatened species (Doremus 2003; Joint Nature Conservation Committee (JNCC) 2007).

Changes to England’s planning system provide a timely opportunity, both nationally and regionally, to revaluate small-scale habitats by reimagining our economic and cultural relationships with brownfield biodiversity (Table 3). For instance, recent shifts away from expected manicured informal urban greenspaces, such as roadside verges, can provide potential cost-saving measures for local councils, exemplifying the opportunity to revalue the varied aesthetics of natural succession on pockets of previously developed spaces (O’Sullivan et al. 2017). Brownfield sites can similarly provide opportunities to create inner-urban greenspaces and corridors which can help with education on urban species by including signposted walkways and observation benches whilst also avoiding large-scale re-disturbance of contaminated sites (Doick et al. 2006). If carefully curated, access to urban wildlife through the protection of biodiverse brownfield sites could bring ecological wealth to local communities besides the economic benefits of redevelopment (De Sousa 2006). Such ecological opportunity is considered essential for humans considering the recent emphasis on local nature and greenspace as a respite from social restrictions in a new pandemic-aware world (Mrema 2020), and for nature through the creation of urban wildlife corridors (Northamptonshire Local Nature Partnership 2016). The increase of “work from home” practices following Covid-19 restrictions could be an opportunity to protect both brownfield and greenfield sites from development by repurposing now vacant office spaces into household and student accommodation etc. Education around the value of ecological succession found on urban brownfield areas and other informal greenspaces has the potential to play an important part in influencing public policy (Table 3) by dismantling current public perceptions toward colour-coded labels of land and facilitating shared experiences between humans and nature that endure time and challenge (Buglife 2009; Bachner and Hill 2014; Chan, Gould, and Pascual 2018). Locally accessible brownfield sites provide opportunities to feature within a “green” curriculum such as the recently proposed Natural History GCSE qualification, as publicised on OCR’s online “Position Statement” (October 2020). Training on the use of the proposed digital consultation platform at the plan-making stages of the new planning system (Table 1) could also ensure greater inclusion of under-represented groups in conservation decisions (Table 3).

A growing public awareness of biodiversity brings to the fore not only the ecological prejudices but the potential social injustices surrounding brownfield site regeneration. Drivers of environmental injustices (i.e., environmental racism and gentrification) include the relocation of spoil piles from brownfield remediation to lower-socio economic and minority ethnic communities, and the reduction in providing affordable housing to recoup remediation costs (Eckerd and Keeler 2012; Essoka 2010). In contrast, solely conserving brownfield biodiversity through its zonal designation as greenspace could potentially contribute to gentrification as “greening” can increase local property values and drive out local residents (Maantay and Maroko 2018). Clearly, development is distinctly interdisciplinary and thus labeling sites purely based on their economic or environmental potential may neglect the panoptic agenda of sustainable development. A proposed zonal system whereby land is granted permission in principle at the plan-making stages may trade the potential flexibility of sites to respond to sustainability challenges when the certainty of their land-use is pre-determined (Gallent et al. 2019).

At the centre of this planning conflict is the contention over whether the positive externalities of development (improved socio-economic conditions) truly outweigh the negatives (habitat and biodiversity loss) (Vihola and Kurvinen 2016). The government’s objectives to infill brownfield sites may be reflective of the interdisciplinary imbalance of existing planning processes. Current attitudes toward the field of ecology in development planning align with a “subordination-service relationship”, in which a “service” discipline is “commonly understood to be making up for…an absence or lack in the other” (Barry, Born, and Weszkalnys 2008, 28). Put simply, ecological services are employed “to tick a box and that’s it” (Ecologist A). By inappropriately utilising ecological expertise in decision-making, the planning system fails to capture the value of brownfield sites to biodiversity, instead underlining social sustainability through the rejuvenation of urban neighborhoods and economic prosperity. However, in the study of the benefits of interdisciplinarity in ecological challenges, Høyer and Naess (2008, 205) observed that it is naïve to assume that greater knowledge about particular ecological landscapes will “be readily translated into more sustainable practices.” Future decision-making will require leadership that will confidently orchestrate knowledge production, elevate ecological suggestions, and integrate community values through more rigorous commitment to interdisciplinary planning processes. Biodiversity conservation and a growing urban society can be mutually inclusive.

5. Conclusion

This study demonstrated that in a region of pre-largescale urbanisation the planning system is characterised by a plurality of motivations to conserve biodiversity. Mindful of the market motivations behind development decisions, the planning actors recognised the challenges of balancing biodiversity conservation with wider sustainability criteria and development viability, particularly on brownfield sites with high remediation costs. To satisfy conservation guidelines, biodiversity offsetting and ecosystem service approaches generally appeared to result in no biodiversity net loss. However, although common conservational practices, they may not be encompassing of slow successional habitats with little perceived economic or aesthetic value as potentially found on urban brownfield areas.

Respondents from ecological backgrounds felt that a seeming lack of understanding and appreciation of the variability of brownfield biodiversity has seen compliance to planning policy influenced by tradeoffs in favor of profitability with inadequate ecological assessment and mitigation. While ecological expertise is undervalued in development decision-making, national narratives may continue to prioritise brownfield regeneration to the detriment of threatened species. England’s proposed streamlining of the planning system stands to exacerbate these concerns without a concerted effort to rectify historic perceptions, and acknowledge the potential biodiversity of urban brownfield sites.

Recommendations:

1. In anticipation of national changes to development planning, future research should address the effects of zonal planning and early consultation processes on the conservation of biodiversity at varying levels of succession and explore how they may contribute to urban wildlife networks. Biodiversity should be protected and enhanced wherever it occurs, even on brownfield sites, and for this reason full ecological assessments are essential to inform brownfield development decisions within local plans and brownfield registers.

2. Raising awareness on the value of urban greenspace; educational programmes can reconfigure the measure of profit beyond economic framing in development markets to include meaningful and reciprocal relationships with nature. A starting point would be for smaller regions to initiate community mapping projects on the value of local brownfield sites and other informal urban greenspaces, assessing their contribution to green infrastructure (including improving walking and cycling routes) and ability to aid local communities in improving mental and physical health, and social wealth.

3. Rebalancing and reconfiguring interdisciplinary collaboration to include greater ecological leadership; this should be embedded into the planning practices of regions akin to Northamptonshire to capture the variability of biodiversity within the early stages of large-scale urbanisation.

4. Ubiquitous and genuine compliance to environmental policies based on scientific evidence is needed to ensure conscientious sustainable development truly occurs.

Revaluing sites traditionally perceived as unattractive and of little economic and ecological value will enhance biodiversity and set the tone for conservation of nature within future development planning. Has Covid-19 provided the opportunity to think more creatively regarding development and conservation on brownfield sites? Conserving biodiversity need not be an anathema to development, but an opportunity to create a thriving and sustainable future for all.

Disclosure statement

No potential conflict of interest was reported by the authors.