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Buying forests for conservation: contours of a global trend
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ScienceDirect Buying forests for conservation: contours of a global trend Christoph Nolte Acquisitions of private forest rights have become a widespread conservation instrument. Over the past two decades, voluntary transactions have legally protected millions of hectares of private forestland in several countries, notably in the Americas. Limited evidence exists on the overall global magnitude and distribution of acquisitions, the factors driving site selection, and resulting ecological and social impacts. Improved behavioral models of landowners and conservation organizations might help steer acquisitions towards more efficient and equitable outcomes. Opportunities for building such models now exist owing to rapid advances in data, methods, and computing capacity.
Address Department of Earth and Environment, Boston University, 685 Commonwealth Ave, Boston, MA 02215, USA
Private forests play a crucial but underappreciated role in this effort. Approximately 10% of the world’s forests are privately owned [6]. Private forests are common in highincome countries across the Americas, Europe, and Oceania [7], and the predominant form of forest tenure in more than 50 countries [8]. Ownership type can vary from small-scale ‘family forests’ to large-scale investment holdings [9,10]. Private forests rights also exist in the absence of full ownership, such as in timber concessions on public land, non-possessory rights of traditional forest users, and many other arrangements [11]. Within countries, private forests are often located in priority areas for threatened biodiversity [12,13] and face high risks of forest loss and fragmentation [14,15]. The protection of private forests can thus make important contributions for avoiding carbon emissions, species extinctions, and the loss of forest ecosystem services.
Corresponding author: Nolte, Christoph ([email protected])
Current Opinion in Environmental Sustainability 2018, 32:68–75 This review comes from a themed issue on Environmental change issues Edited by Arun Agrawal, Chuan Liao, Cristy Watkins, Laura Vang Rasmussen and Reem Hajjar
Received: 27 November 2017; Revised: 9 March 2018; Accepted: 6 May 2018
https://doi.org/10.1016/j.cosust.2018.05.003 1877-3435/ã 2018 Elsevier B.V. All rights reserved.
Introduction Protecting forests from anthropogenic influence has long been a core goal of conservation advocates around the globe. In the 21st century, concerns about climate change and mass species extinctions have renewed global efforts to reduce global forest loss and degradation [1]. Researchers have joined policy makers and environmental organizations in the search for conservation strategies that are politically viable and deliver desired environmental and social outcomes [2,3]. Their efforts led to a rapid growth in empirical studies on the choice, allocation and impact of forest conservation interventions, fueled by advances in rigorous impact assessment methodologies and longterm, large-scale observations of forest change [4,5]. Current Opinion in Environmental Sustainability 2018, 32:68–75
A rapidly expanding conservation instrument for private forests is the voluntary permanent transfer of property rights. Over the past two decades, rights to tens of thousands of private forest properties have been permanently transferred to public agencies or conservation nongovernmental organizations (NGOs) [16–18]. Scholars have begun to engage with this phenomenon; their contributions are diverse in scope and come from a wide range of disciplines, including environmental science, conservation biology, forestry, law, economics, and geography. Little systematic evidence exists on the global extent and distribution of forest right acquisitions, the factors driving site selection, and the long-term ecological and social impacts. As a result, it is difficult to assess whether, where, and how forest acquisitions contribute to the conservation of forest values. Here I synthesize the current literature on acquisitions of private forest rights for conservation. I define those as ‘voluntary permanent transactions of private rights to forestland that occur with the intention to conserve ecological values in perpetuity’. My definition covers acquisitions and donations of full (e.g. ownership) or partial rights (e.g. easements, covenants, and servitudes), as long as the recipient has either the legal obligation or the declared core mission to conserve ecological values forever. I also consider declarations of private protected areas if they involve permanent transfers of rights. Excluded from the scope of this review are temporary transactions (e.g. payments for environmental services), regulatory approaches (e.g. land use zoning), or transactions between non-private entities (e.g. REDD+) which www.sciencedirect.com
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Figure 1 Public conservation actors: national, subnational, local
Purchase, tax incentives (optional)
Full or partial rights (voluntary)
Private forest owner
Private conservation actors: NGOs, individuals Purchase (optional) Current Opinion in Environmental Sustainability
Forest right acquisitions for conservation (schematic representation).
have been treated more extensively elsewhere [19–21] and in other contributions to this special issue (Figure 1).
Scale and actors Efforts to characterize the global scale and distribution of forest right acquisitions are complicated by the absence of comparable statistics. However, in terms of broad patterns, two assumptions seem plausible. First, forest right acquisitions will be more widespread in countries with large privately-owned forests. Globally, the U.S. and Brazil have the largest forests under private ownership. The tenure form is also predominant in several countries across the Americas (e.g. Argentina, Canada, Chile, Paraguay), Europe (e.g. Germany, Finland, France, Italy, Spain, Sweden), and Australia [8,22]. Second, conservation actors are more likely to choose forest right acquisitions as a conservation instrument if the main alternative — regulation — is perceived as unfeasible or unlikely to protect ecological values to the extent desired by those actors. Fertile ground for acquisitions will thus exist in localities whose political culture has historically favored private property rights over regulatory approaches to landscape conservation. Insights from the literature appear to corroborate these assumptions. Land acquisitions for conservation are widespread in the U.S., where 1363 active land trusts protected more than 15 million hectares through transactions of full or partial rights [17], public spending for conservation www.sciencedirect.com
acquisitions exceeded $40 billion over the last two decades [16,23], and tax incentives for charitable donations of land rights can be generous [24]. The activity is widespread across forest landscapes [25,26,27] and includes funding programs specifically dedicated to forest conservation [28]. Significant country-level activity in conservation-oriented acquisitions of forest rights has also been reported from Australia [29–31], Brazil [32], Canada [33], Chile [18], Colombia [34], Denmark [35] and Finland [36]. International transactions occurred in at least 20 tropical countries [37]. In addition, many countries have developed frameworks for the creation of ‘privately protected areas’ (PPAs), which, in some instances, also involve the permanent abandonment of private land rights [38–40]. Forest acquisitions involve actors with diverse constituencies and interests. Public agencies, NGOs, and private individuals have acted as funders, deal makers, or postdeal stewards. Acquisitions in the U.S. and Australia involve a strong interplay of public and private conservation organizations [16,29,41]. In other countries, studies have focused either on publicly (e.g. Colombia, Denmark, Finland [34,35,36]) or privately funded acquisitions (e.g. Brazil, Canada, Chile [18,32,33]). Funding for acquisitions of forest rights can come from local [42], subnational [16], national [28], and international sources [18,37]. Organizational interests in forest conservation are diverse, ranging from the conservation of species, Current Opinion in Environmental Sustainability 2018, 32:68–75
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carbon, scenic views, hydrological functions and other ecological services to the provision of recreational access, hunting grounds, or timber production. Forest acquisitions can vary substantially in size. Emblematic cases from the last 25 years include the 296 000 ha Pumalı´n Park in Chile [43], Johan Eliasch’s 160 000 ha acquisition of Brazilian Amazon rainforest [44], and forestry easements in Maine (U.S.), several of which exceeded 100 000 ha [45]. Most acquisitions occur at smaller scales. In the U.S., the median size of 55 253 forest parcels protected with direct public funding 1998– 2016 was 17 ha, and the median size of 56 875 easements on forest parcels was 12 ha.1 Few studies from other countries offer summary statistics on parcel size. Yet, even in the absence of global statistics, it appears safe to state that forest right acquisitions are now occurring at scales that, in some geographies, rival those of other forest conservation interventions. Given their widespread use, what do we know about their effectiveness?
Allocation Ecological and social outcomes of conservation interventions depend on their location within a landscape. Spatial prioritization has therefore long been a cornerstone of conservation planning: given specific goals and budgets, where are priority locations for investments [46,47]? Reallife landscape conservation, however, rarely follows such algorithms [48]. Goals are seldom well-specified, measurable, and unequivocally shared among all organizations. Budget constraints might be clear for a specific program and funding period, but those programs will in turn be affected by changing preferences of constituencies and attributes of candidate sites. Furthermore, as forest right acquisitions are voluntary, the propensity of landowners to sell or donate property rights bears a major influence on where conservation ultimately occurs [49]. Recognizing the importance of landowner preferences in shaping forest acquisitions, scholars in several countries have begun to elicit such preferences systematically. Surveys of potential [50–55,56] and actual participants [57–60] in the U.S., Australia, and South Africa find attitudes towards permanent conservation to be linked to characteristics of individuals (age, gender, income, environmental values, sense of place), properties (size, current use, habitat) and contracts (scale and type of restrictions, size of incentive, public access, post-deal right holder). Each study focuses on a smaller subset of these attributes, and systematic syntheses of findings across surveys, models and geographies are absent. In that light, the main takeaway is that landowner attitudes towards protecting their land are complex, diverse, and context-specific. 1
Own computations, based on spatial data from Refs. [16,45], using parcels with >25% forest cover [109]. Current Opinion in Environmental Sustainability 2018, 32:68–75
Preferences of conservation organizations have also been the subject of inquiry. Many organizations involved in forest right acquisitions openly declare their priorities on public-facing websites, but these are usually expressed in vague terms. In a nationwide U.S. census, land trusts identified as top priorities the conservation of natural areas, wildlife habitat, water, and wetlands; other priorities include working farms and ranchlands, recreation lands, scenic views and landscapes, working forestland, and historic or cultural resources [17]. Stated choice surveys of land trust experts reveal a preference for wildlife habitat and biodiversity, large contiguous forests, and riparian lands [61,62,63]. Researchers have also deduced the characteristics of local conservation demand from the preferences of rural homeowners [64–67]. However, how such demand in turn affects the allocation of conservation is unclear, as opinions of land trust experts can differ from those of the local public [62]. In the first direct quantitative comparison of the preferences of landowners and conservation organizations, the authors finds that both sides favor permanent easements and are motivated by community and place attachment, but differ on issues such as managerial control and public access [63]. Given this diversity of preferences and attributes, what are the main drivers of permanent forest conservation in practice? Few studies attempt to answer this questions empirically. One study of U.S. forest owners finds wealthier individuals with larger properties and forest management plans to be more likely to have easements on their properties [68]. In Denmark, permanent restrictions were more frequently adopted by younger, non-agricultural landowners with higher forest cover on their land [35]. In Australia, non-production landholders participated in conservation auctions more often and offered lower bids [69]. In the Appalachian region, the location of easements was found to be more strongly associated with median incomes and distance to infrastructure than with environmental factors such as topography, soil quality and land cover diversity [26]. In addition to such systematic patterns, researchers also identify factors that can introduce randomness, such as sudden changes in landowner family situations [70]. Beyond attributes of individual landowners, several U.S. studies have highlighted the importance of large-scale contextual factors in affecting were forest right acquisitions occur. For instance, rates of private land protection increased in specific regions during economic transitions, for example, forestland divestment in Wisconsin and New England [71,72], or after large-scale catastrophes, for example, floods in the Missouri floodplain [73]. Tax incentives and public investments have also been shown to influence the rate of private land conservation across space and time [24,74,75]. It is less clear whether the allocation of conservation has been affected by improved knowledge and planning tools; one study finds that www.sciencedirect.com
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improvements in conservation planning by the largest U.S. land trust did not affect its land acquisition patterns over a 40 year period [76]. Outside the U.S., spatial drivers of forest right acquisitions are rarely examined systematically.
Impact Do we know whether forest acquisitions are an effective tool for delivering ecological and social benefits? Most actors with direct involvement in acquisitions will refer to successful transactions as ‘win–win’ cases for landowners and conservation. Given the voluntary nature of these transactions, this assumption of mutual benefit appears plausible — certainly more so than in the case of coercive conservation measures. However, costs can incur to people not at the table. First, landowners giving up land rights often receive public funds, either through direct payments or as tax incentives in the case of charitable donations. In the U.S. alone, public expenses for land acquisitions between 2000 and 2015 ranged between $2 and $3.5 billion per year [16,77]. Secondly, transaction costs of deal making and stewardship are non-negligible: again in the U.S., land trusts employ more than 8100 staff and manage $2.1 billion of funding, including $588 million for stewardship and legal defense [17]. Thirdly, ‘public’ preferences about forests are not homogenous; locking in the use of a given parcel for perpetuity, whether it be for species conservation, recreational access, hunting, ranching, or timber production, might benefit some stakeholders but affect others negatively. Finally, forest acquisitions do not challenge existing distributions of land rights, which are highly unequal in many countries and have often been obtained at the expense of indigenous and marginalized land users [78]. Understanding the net benefits of acquisition thus requires a more comprehensive perspective on costs, benefits, and the distribution among affected individuals. It also requires an explicit consideration of counterfactual outcomes [79]: what would have happened if the acquisition had not occurred? Forest acquisitions might be expected to result in tangible improvements in ecological conditions over businessas-usual. However, existing evidence for this claim remains surprisingly inconclusive. Several studies examine spatial patterns of land acquisitions as a proxy for ecological outcomes, and find evidence of clustering in space [71,80], enhanced connectivity [81,82], and improved representation [82,83]. Yet the location of conservation alone is insufficient as a conservation measure [84]. The specific terms of protection can vary across space and time, and in the U.S., easements have become more complex and less restrictive over time [85,86,87]. In that light, it seems surprising that even simple ecological outcomes are rarely assessed, as monitoring of protected forests is the exception rather than a rule www.sciencedirect.com
[30,88,89]. Counterfactual impact studies are almost absent. One quasi-experimental analysis suggests that forest easements in the U.S. did not lead to an adoption of improved forest management practices other than the creation of forest management plans [90]. A remote sensing study in Maine finds no difference in forest disturbance on properties with and without easements [91]. In a simulation study of threat abatement in a California landscape, easements were projected to result in only minor impacts on housing development over a 50 year period [92]. Although scarce, this evidence suggests that short and medium-term impacts of perpetual land conservation can be small if actions are located in areas of low anthropogenic pressure or if they impose few new restrictions. Social outcomes of forest right acquisitions are rarely examined. Conservation organizations cater to a wide range of social demands [81], making it difficult for any study to consider the full range of benefits. However, some specific insights exist. In the U.S., public recreational access, often considered a key benefit [93], is commonly provided by conservation organizations on their own properties [94], but less so on easements, as landowners tend to dislike it [63,95]; this absence of visitation, in turn, might have positively affected conservation outcomes on easements [96]. Localized benefits of conservation acquisitions have been inferred from increases in nearby land values [97,98], a phenomenon that can also undermine future protection efforts and induce leakage [99]. In the international context, largescale forest acquisitions have faced criticism of green grabbing [100].
Conclusions What role do forest right acquisitions play in the conservation of forest values — and how can their performance be improved? In spite of a rich empirical reality and rapidly growing literature, robust answers remain in their infancy. Even for goals that appear to be widely shared among conservation supporters — such as carbon storage, species protection, and public access — few studies offer rigorous estimates of impact. This is true even in the U.S., whose unparalleled scale of forest right acquisitions has inspired significant academic productivity. For other countries, even basic indicators, such as the overall scale of forest right acquisitions, are lacking. Such scarcity of evidence provides a reason for concern, given that acquisitions are now a well-established (and occasionally wellfunded) conservation instrument, but few studies have identified measurable impacts on ecological outcomes, at least in the short run. To steer forest right acquisitions towards higher public benefit, analysts will not only have to begin quantifying such impacts more comprehensively. They will also have to develop a more systematic, contextualized Current Opinion in Environmental Sustainability 2018, 32:68–75
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understanding of how multiple organizations, each with their own preferences, internal rules, and funding streams, but all interacting in the same landscape with the same range of diverse landowners, produce a given spatial pattern of protection. To inform policy, more evidence is also needed on how such systems will respond to new programs and funding streams with different design attributes (e.g. eligibility, site selection, price discovery). Tax incentives, for instance, have been shown to accelerate the pace of conservation [24], but they also have encouraged fraudulent activity [101] and might detract conservation attention from high-priority areas. Information, such as identifying priority habitats under climate change, can influence where protection occurs, but only if decision makers and funders are responsive to it [76]. New opportunities to build a better empirical understanding of those dynamics now exist. Improvements in data, inferential methods, and computational capacity allow researchers to quantify impact and model allocation at scales and resolutions that were out of reach just a decade ago. In the U.S., national data on conservation priorities [13], parcel boundaries and sales, public spending on land transactions [16], the spatial locations of protected lands [102,103], and multi-decadal land cover change [104,105] are improving rapidly. In combination, these datasets allow for a wide range of new analyses, including: (1) quantifying the impact of forest acquisitions on land cover change and fragmentation at parcel-level resolution and continental scales for different types of actors (e.g. federal, state, local, vs. NGO), acquisition strategies (full or partial), and geographies, (2) developing and testing parcel-level models of the real-life site selection behavior of conservation organizations and their interactions with landowners, permitting predictions regarding outcomes and benefits of future policies and programs, (3) developing and empirically calibrating estimates of the cost of conserving any given parcel, which would not only help close a long-standing gap in conservation planning [106], but might also assist regulators in combating easement fraud [107].
In other countries, datasets with similar thematic reach might not yet exist, but can often be compiled through targeted data collection efforts [108]. Overall, conditions for new research on the scale, cost, allocation, and impact of forest right acquisitions seem more favorable than ever before. It seems likely that we will witness evidence gaps narrow over the next few years.
Acknowledgements I thank Arun Agrawal, Paul Armsworth, and two anonymous reviewers for valuable feedback.
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77. Looney A: Charitable Contributions of Conservation Easements. 2017. 78. Sikor T, Stahl J, Enters T, Ribot JC, Singh N, Sunderlin WD, Wollenberg L: REDD-plus, forest people’s rights and nested climate governance [Internet]. Glob Environ Chang 2010, 20:423-425. 79. Ferraro PJ: Counterfactual thinking and impact evaluation in environmental policy. New Dir Eval 2009, 2009:75-84. 80. McDonald RI, Yuan-Farrell C, Fievet C, Moeller M, Kareiva P, Foster D, Gragson T, Kinzig A, Kuby L, Redman C: Estimating the effect of protected lands on the development and conservation of their surroundings. Conserv Biol 2007, 21: 1526-1536. 81. Wallace GN, Theobald DM, Ernst T, King K: Assessing the ecological and social benefits of private land conservation in Colorado. Conserv Biol 2008, 22:284-296. 82. Rissman AR, Merenlender AM: The conservation contributions of conservation easements: analysis of the San Francisco Bay area protected lands spatial database. Ecol Soc 2008:13. 83. Santos MJ, Thorne JH, Christensen J, Frank Z: An historical land conservation analysis in the San Francisco Bay Area, USA: 1850–2010. Landsc Urban Plan 2014, 127:114-123. 84. Chape S, Harrison J, Spalding M, Lysenko I: Measuring the extent and effectiveness of protected areas as an indicator for meeting global biodiversity targets. Philos Trans R Soc Lond B Biol Sci 2005, 360:443-455. 85. Owley J, Rissman AR: Trends in private land conservation: increasing complexity, shifting conservation purposes and allowable private land uses. Land Use Policy 2016, 51:76-84. Based on a detailed database of 269 conservation easements, the authors observe that easements have become more complex and less restrictive over time. 86. Rissman A, Bihari M, Hamilton C, Locke C, Lowenstein D, Motew M, Price J, Smail R: Land management restrictions and options for change in perpetual conservation easements. Environ Manage 2013, 52:277-288. 87. Rissman AR, Owley J, Shaw MR, Thompson BB: Adapting conservation easements to climate change. Conserv Lett 2015, 8:68-76. 88. Neugarten RA, Wolf SA, Stedman RC, Tear TH: Integrating ecological and socioeconomic monitoring of working forests. BioScience 2011, 61:631-637. 89. Alexander L, Hess GR: Land trust evaluation of progress toward conservation goals. Conserv Biol 2012, 26:7-12. 90. Song N, Aguilar FX, Butler BJ: Conservation easements and management by family forest owners: a propensity score matching approach with multi-imputations of survey data. For Sci 2014, 60:298-307. 91. Noone MD, Sader SA, Legaard KR: Are forest disturbance rates and composition influenced by changing ownerships, conservation easements, and land certification? For Sci 2012, 58:119-129. 92. Byrd KB, Rissman AR, Merenlender AM: Impacts of conservation easements for threat abatement and fire management in a rural oak woodland landscape. Landsc Urban Plan 2009, 92:106-116. 93. Daigle JJ, Utley L, Chase LC, Kuentzel WF, Brown TL: Does new large private landownership and their management priorities influence public access in the northern forest? J For 2012, 110:89-96. 94. Lieberknecht K: Public access to U.S. conservation land trust properties: results from a national survey. J Am Plan Assoc 2009, 75:479-491. 95. Miller AD, Bastian CT, McLeod DM, Keske CM, Hoag DL: Factors impacting agricultural landowners’ willingness to enter into conservation easements: a case study. Soc Nat Resour 2010, 24:65-74. www.sciencedirect.com
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Current Opinion in Environmental Sustainability 2018, 32:68–75
ScienceDirect Buying forests for conservation: contours of a global trend Christoph Nolte Acquisitions of private forest rights have become a widespread conservation instrument. Over the past two decades, voluntary transactions have legally protected millions of hectares of private forestland in several countries, notably in the Americas. Limited evidence exists on the overall global magnitude and distribution of acquisitions, the factors driving site selection, and resulting ecological and social impacts. Improved behavioral models of landowners and conservation organizations might help steer acquisitions towards more efficient and equitable outcomes. Opportunities for building such models now exist owing to rapid advances in data, methods, and computing capacity.
Address Department of Earth and Environment, Boston University, 685 Commonwealth Ave, Boston, MA 02215, USA
Private forests play a crucial but underappreciated role in this effort. Approximately 10% of the world’s forests are privately owned [6]. Private forests are common in highincome countries across the Americas, Europe, and Oceania [7], and the predominant form of forest tenure in more than 50 countries [8]. Ownership type can vary from small-scale ‘family forests’ to large-scale investment holdings [9,10]. Private forests rights also exist in the absence of full ownership, such as in timber concessions on public land, non-possessory rights of traditional forest users, and many other arrangements [11]. Within countries, private forests are often located in priority areas for threatened biodiversity [12,13] and face high risks of forest loss and fragmentation [14,15]. The protection of private forests can thus make important contributions for avoiding carbon emissions, species extinctions, and the loss of forest ecosystem services.
Corresponding author: Nolte, Christoph ([email protected])
Current Opinion in Environmental Sustainability 2018, 32:68–75 This review comes from a themed issue on Environmental change issues Edited by Arun Agrawal, Chuan Liao, Cristy Watkins, Laura Vang Rasmussen and Reem Hajjar
Received: 27 November 2017; Revised: 9 March 2018; Accepted: 6 May 2018
https://doi.org/10.1016/j.cosust.2018.05.003 1877-3435/ã 2018 Elsevier B.V. All rights reserved.
Introduction Protecting forests from anthropogenic influence has long been a core goal of conservation advocates around the globe. In the 21st century, concerns about climate change and mass species extinctions have renewed global efforts to reduce global forest loss and degradation [1]. Researchers have joined policy makers and environmental organizations in the search for conservation strategies that are politically viable and deliver desired environmental and social outcomes [2,3]. Their efforts led to a rapid growth in empirical studies on the choice, allocation and impact of forest conservation interventions, fueled by advances in rigorous impact assessment methodologies and longterm, large-scale observations of forest change [4,5]. Current Opinion in Environmental Sustainability 2018, 32:68–75
A rapidly expanding conservation instrument for private forests is the voluntary permanent transfer of property rights. Over the past two decades, rights to tens of thousands of private forest properties have been permanently transferred to public agencies or conservation nongovernmental organizations (NGOs) [16–18]. Scholars have begun to engage with this phenomenon; their contributions are diverse in scope and come from a wide range of disciplines, including environmental science, conservation biology, forestry, law, economics, and geography. Little systematic evidence exists on the global extent and distribution of forest right acquisitions, the factors driving site selection, and the long-term ecological and social impacts. As a result, it is difficult to assess whether, where, and how forest acquisitions contribute to the conservation of forest values. Here I synthesize the current literature on acquisitions of private forest rights for conservation. I define those as ‘voluntary permanent transactions of private rights to forestland that occur with the intention to conserve ecological values in perpetuity’. My definition covers acquisitions and donations of full (e.g. ownership) or partial rights (e.g. easements, covenants, and servitudes), as long as the recipient has either the legal obligation or the declared core mission to conserve ecological values forever. I also consider declarations of private protected areas if they involve permanent transfers of rights. Excluded from the scope of this review are temporary transactions (e.g. payments for environmental services), regulatory approaches (e.g. land use zoning), or transactions between non-private entities (e.g. REDD+) which www.sciencedirect.com
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Figure 1 Public conservation actors: national, subnational, local
Purchase, tax incentives (optional)
Full or partial rights (voluntary)
Private forest owner
Private conservation actors: NGOs, individuals Purchase (optional) Current Opinion in Environmental Sustainability
Forest right acquisitions for conservation (schematic representation).
have been treated more extensively elsewhere [19–21] and in other contributions to this special issue (Figure 1).
Scale and actors Efforts to characterize the global scale and distribution of forest right acquisitions are complicated by the absence of comparable statistics. However, in terms of broad patterns, two assumptions seem plausible. First, forest right acquisitions will be more widespread in countries with large privately-owned forests. Globally, the U.S. and Brazil have the largest forests under private ownership. The tenure form is also predominant in several countries across the Americas (e.g. Argentina, Canada, Chile, Paraguay), Europe (e.g. Germany, Finland, France, Italy, Spain, Sweden), and Australia [8,22]. Second, conservation actors are more likely to choose forest right acquisitions as a conservation instrument if the main alternative — regulation — is perceived as unfeasible or unlikely to protect ecological values to the extent desired by those actors. Fertile ground for acquisitions will thus exist in localities whose political culture has historically favored private property rights over regulatory approaches to landscape conservation. Insights from the literature appear to corroborate these assumptions. Land acquisitions for conservation are widespread in the U.S., where 1363 active land trusts protected more than 15 million hectares through transactions of full or partial rights [17], public spending for conservation www.sciencedirect.com
acquisitions exceeded $40 billion over the last two decades [16,23], and tax incentives for charitable donations of land rights can be generous [24]. The activity is widespread across forest landscapes [25,26,27] and includes funding programs specifically dedicated to forest conservation [28]. Significant country-level activity in conservation-oriented acquisitions of forest rights has also been reported from Australia [29–31], Brazil [32], Canada [33], Chile [18], Colombia [34], Denmark [35] and Finland [36]. International transactions occurred in at least 20 tropical countries [37]. In addition, many countries have developed frameworks for the creation of ‘privately protected areas’ (PPAs), which, in some instances, also involve the permanent abandonment of private land rights [38–40]. Forest acquisitions involve actors with diverse constituencies and interests. Public agencies, NGOs, and private individuals have acted as funders, deal makers, or postdeal stewards. Acquisitions in the U.S. and Australia involve a strong interplay of public and private conservation organizations [16,29,41]. In other countries, studies have focused either on publicly (e.g. Colombia, Denmark, Finland [34,35,36]) or privately funded acquisitions (e.g. Brazil, Canada, Chile [18,32,33]). Funding for acquisitions of forest rights can come from local [42], subnational [16], national [28], and international sources [18,37]. Organizational interests in forest conservation are diverse, ranging from the conservation of species, Current Opinion in Environmental Sustainability 2018, 32:68–75
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carbon, scenic views, hydrological functions and other ecological services to the provision of recreational access, hunting grounds, or timber production. Forest acquisitions can vary substantially in size. Emblematic cases from the last 25 years include the 296 000 ha Pumalı´n Park in Chile [43], Johan Eliasch’s 160 000 ha acquisition of Brazilian Amazon rainforest [44], and forestry easements in Maine (U.S.), several of which exceeded 100 000 ha [45]. Most acquisitions occur at smaller scales. In the U.S., the median size of 55 253 forest parcels protected with direct public funding 1998– 2016 was 17 ha, and the median size of 56 875 easements on forest parcels was 12 ha.1 Few studies from other countries offer summary statistics on parcel size. Yet, even in the absence of global statistics, it appears safe to state that forest right acquisitions are now occurring at scales that, in some geographies, rival those of other forest conservation interventions. Given their widespread use, what do we know about their effectiveness?
Allocation Ecological and social outcomes of conservation interventions depend on their location within a landscape. Spatial prioritization has therefore long been a cornerstone of conservation planning: given specific goals and budgets, where are priority locations for investments [46,47]? Reallife landscape conservation, however, rarely follows such algorithms [48]. Goals are seldom well-specified, measurable, and unequivocally shared among all organizations. Budget constraints might be clear for a specific program and funding period, but those programs will in turn be affected by changing preferences of constituencies and attributes of candidate sites. Furthermore, as forest right acquisitions are voluntary, the propensity of landowners to sell or donate property rights bears a major influence on where conservation ultimately occurs [49]. Recognizing the importance of landowner preferences in shaping forest acquisitions, scholars in several countries have begun to elicit such preferences systematically. Surveys of potential [50–55,56] and actual participants [57–60] in the U.S., Australia, and South Africa find attitudes towards permanent conservation to be linked to characteristics of individuals (age, gender, income, environmental values, sense of place), properties (size, current use, habitat) and contracts (scale and type of restrictions, size of incentive, public access, post-deal right holder). Each study focuses on a smaller subset of these attributes, and systematic syntheses of findings across surveys, models and geographies are absent. In that light, the main takeaway is that landowner attitudes towards protecting their land are complex, diverse, and context-specific. 1
Own computations, based on spatial data from Refs. [16,45], using parcels with >25% forest cover [109]. Current Opinion in Environmental Sustainability 2018, 32:68–75
Preferences of conservation organizations have also been the subject of inquiry. Many organizations involved in forest right acquisitions openly declare their priorities on public-facing websites, but these are usually expressed in vague terms. In a nationwide U.S. census, land trusts identified as top priorities the conservation of natural areas, wildlife habitat, water, and wetlands; other priorities include working farms and ranchlands, recreation lands, scenic views and landscapes, working forestland, and historic or cultural resources [17]. Stated choice surveys of land trust experts reveal a preference for wildlife habitat and biodiversity, large contiguous forests, and riparian lands [61,62,63]. Researchers have also deduced the characteristics of local conservation demand from the preferences of rural homeowners [64–67]. However, how such demand in turn affects the allocation of conservation is unclear, as opinions of land trust experts can differ from those of the local public [62]. In the first direct quantitative comparison of the preferences of landowners and conservation organizations, the authors finds that both sides favor permanent easements and are motivated by community and place attachment, but differ on issues such as managerial control and public access [63]. Given this diversity of preferences and attributes, what are the main drivers of permanent forest conservation in practice? Few studies attempt to answer this questions empirically. One study of U.S. forest owners finds wealthier individuals with larger properties and forest management plans to be more likely to have easements on their properties [68]. In Denmark, permanent restrictions were more frequently adopted by younger, non-agricultural landowners with higher forest cover on their land [35]. In Australia, non-production landholders participated in conservation auctions more often and offered lower bids [69]. In the Appalachian region, the location of easements was found to be more strongly associated with median incomes and distance to infrastructure than with environmental factors such as topography, soil quality and land cover diversity [26]. In addition to such systematic patterns, researchers also identify factors that can introduce randomness, such as sudden changes in landowner family situations [70]. Beyond attributes of individual landowners, several U.S. studies have highlighted the importance of large-scale contextual factors in affecting were forest right acquisitions occur. For instance, rates of private land protection increased in specific regions during economic transitions, for example, forestland divestment in Wisconsin and New England [71,72], or after large-scale catastrophes, for example, floods in the Missouri floodplain [73]. Tax incentives and public investments have also been shown to influence the rate of private land conservation across space and time [24,74,75]. It is less clear whether the allocation of conservation has been affected by improved knowledge and planning tools; one study finds that www.sciencedirect.com
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improvements in conservation planning by the largest U.S. land trust did not affect its land acquisition patterns over a 40 year period [76]. Outside the U.S., spatial drivers of forest right acquisitions are rarely examined systematically.
Impact Do we know whether forest acquisitions are an effective tool for delivering ecological and social benefits? Most actors with direct involvement in acquisitions will refer to successful transactions as ‘win–win’ cases for landowners and conservation. Given the voluntary nature of these transactions, this assumption of mutual benefit appears plausible — certainly more so than in the case of coercive conservation measures. However, costs can incur to people not at the table. First, landowners giving up land rights often receive public funds, either through direct payments or as tax incentives in the case of charitable donations. In the U.S. alone, public expenses for land acquisitions between 2000 and 2015 ranged between $2 and $3.5 billion per year [16,77]. Secondly, transaction costs of deal making and stewardship are non-negligible: again in the U.S., land trusts employ more than 8100 staff and manage $2.1 billion of funding, including $588 million for stewardship and legal defense [17]. Thirdly, ‘public’ preferences about forests are not homogenous; locking in the use of a given parcel for perpetuity, whether it be for species conservation, recreational access, hunting, ranching, or timber production, might benefit some stakeholders but affect others negatively. Finally, forest acquisitions do not challenge existing distributions of land rights, which are highly unequal in many countries and have often been obtained at the expense of indigenous and marginalized land users [78]. Understanding the net benefits of acquisition thus requires a more comprehensive perspective on costs, benefits, and the distribution among affected individuals. It also requires an explicit consideration of counterfactual outcomes [79]: what would have happened if the acquisition had not occurred? Forest acquisitions might be expected to result in tangible improvements in ecological conditions over businessas-usual. However, existing evidence for this claim remains surprisingly inconclusive. Several studies examine spatial patterns of land acquisitions as a proxy for ecological outcomes, and find evidence of clustering in space [71,80], enhanced connectivity [81,82], and improved representation [82,83]. Yet the location of conservation alone is insufficient as a conservation measure [84]. The specific terms of protection can vary across space and time, and in the U.S., easements have become more complex and less restrictive over time [85,86,87]. In that light, it seems surprising that even simple ecological outcomes are rarely assessed, as monitoring of protected forests is the exception rather than a rule www.sciencedirect.com
[30,88,89]. Counterfactual impact studies are almost absent. One quasi-experimental analysis suggests that forest easements in the U.S. did not lead to an adoption of improved forest management practices other than the creation of forest management plans [90]. A remote sensing study in Maine finds no difference in forest disturbance on properties with and without easements [91]. In a simulation study of threat abatement in a California landscape, easements were projected to result in only minor impacts on housing development over a 50 year period [92]. Although scarce, this evidence suggests that short and medium-term impacts of perpetual land conservation can be small if actions are located in areas of low anthropogenic pressure or if they impose few new restrictions. Social outcomes of forest right acquisitions are rarely examined. Conservation organizations cater to a wide range of social demands [81], making it difficult for any study to consider the full range of benefits. However, some specific insights exist. In the U.S., public recreational access, often considered a key benefit [93], is commonly provided by conservation organizations on their own properties [94], but less so on easements, as landowners tend to dislike it [63,95]; this absence of visitation, in turn, might have positively affected conservation outcomes on easements [96]. Localized benefits of conservation acquisitions have been inferred from increases in nearby land values [97,98], a phenomenon that can also undermine future protection efforts and induce leakage [99]. In the international context, largescale forest acquisitions have faced criticism of green grabbing [100].
Conclusions What role do forest right acquisitions play in the conservation of forest values — and how can their performance be improved? In spite of a rich empirical reality and rapidly growing literature, robust answers remain in their infancy. Even for goals that appear to be widely shared among conservation supporters — such as carbon storage, species protection, and public access — few studies offer rigorous estimates of impact. This is true even in the U.S., whose unparalleled scale of forest right acquisitions has inspired significant academic productivity. For other countries, even basic indicators, such as the overall scale of forest right acquisitions, are lacking. Such scarcity of evidence provides a reason for concern, given that acquisitions are now a well-established (and occasionally wellfunded) conservation instrument, but few studies have identified measurable impacts on ecological outcomes, at least in the short run. To steer forest right acquisitions towards higher public benefit, analysts will not only have to begin quantifying such impacts more comprehensively. They will also have to develop a more systematic, contextualized Current Opinion in Environmental Sustainability 2018, 32:68–75
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understanding of how multiple organizations, each with their own preferences, internal rules, and funding streams, but all interacting in the same landscape with the same range of diverse landowners, produce a given spatial pattern of protection. To inform policy, more evidence is also needed on how such systems will respond to new programs and funding streams with different design attributes (e.g. eligibility, site selection, price discovery). Tax incentives, for instance, have been shown to accelerate the pace of conservation [24], but they also have encouraged fraudulent activity [101] and might detract conservation attention from high-priority areas. Information, such as identifying priority habitats under climate change, can influence where protection occurs, but only if decision makers and funders are responsive to it [76]. New opportunities to build a better empirical understanding of those dynamics now exist. Improvements in data, inferential methods, and computational capacity allow researchers to quantify impact and model allocation at scales and resolutions that were out of reach just a decade ago. In the U.S., national data on conservation priorities [13], parcel boundaries and sales, public spending on land transactions [16], the spatial locations of protected lands [102,103], and multi-decadal land cover change [104,105] are improving rapidly. In combination, these datasets allow for a wide range of new analyses, including: (1) quantifying the impact of forest acquisitions on land cover change and fragmentation at parcel-level resolution and continental scales for different types of actors (e.g. federal, state, local, vs. NGO), acquisition strategies (full or partial), and geographies, (2) developing and testing parcel-level models of the real-life site selection behavior of conservation organizations and their interactions with landowners, permitting predictions regarding outcomes and benefits of future policies and programs, (3) developing and empirically calibrating estimates of the cost of conserving any given parcel, which would not only help close a long-standing gap in conservation planning [106], but might also assist regulators in combating easement fraud [107].
In other countries, datasets with similar thematic reach might not yet exist, but can often be compiled through targeted data collection efforts [108]. Overall, conditions for new research on the scale, cost, allocation, and impact of forest right acquisitions seem more favorable than ever before. It seems likely that we will witness evidence gaps narrow over the next few years.
Acknowledgements I thank Arun Agrawal, Paul Armsworth, and two anonymous reviewers for valuable feedback.
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Funding sources This research was supported by Boston University. Current Opinion in Environmental Sustainability 2018, 32:68–75
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