Forest clearances, compensatory afforestation and biodiversity offsetting in forests: Balancing flexibility and equivalency in Switzerland

The settlement area is expanding at the cost of agricultural land in densely populated regions such as Central Europe. This development is also affecting the forest. Forest clearances due to, e.g. traffic and energy infrastructure development, require afforestation elsewhere but surfaces providing appropriate soil are increasingly scarce. Switzerland is an important case in point. It is densely populated, exhibits a large amount of forest – also in the lowlands – and although it features a strong forest protection law, it recently allowed compensating forest clearances with non-forest related offsets. Based on the results of a Q-methodology survey conducted during a stakeholder workshop, we show that pressure for more flexible forest specific rules largely stems from “ outside ” the forest sector, i.e. the agriculture and development sector. Only a small group of actors aims at reinstalling the more restrictive regime, whereas the largest group of actors embraces the status quo. This group rejects expansion of more flexible rules and adheres to strengthening the top of the mitigation hierarchy, i.e. prioritizing the mitigation of habitat loss caused by development. This interpretation of biodiversity offsetting aligns with the conviction that development needs to respect the limits of growth. Prioritizing the mitigation hierarchy requires a planning rather than a market coordination approach. We show that in a context with rigid biodiversity off-setting rules, following a multipurpose forest regime and with high land-use competition, stakeholder preferences impede the integration of habitat banking approaches into the planning of compensatory afforestation and biodiversity offsetting in the forest.


Introduction
Containing the expansion of settlement areas is one of the key challenges in densely populated metropolitan areas of Central European countries.While biodiversity has primarily been threatened by the dominance of homogenous agricultural production landscapes (Noack et al., 2022), advancing urbanizationespecially at the urban fringeat the expense of agricultural land increases land-use competition (OECD, 2009, 46f;Steinhäußer et al., 2015) and further threatens natural capital.Biodiversity offset regulation, i.e. the requirement to mitigate the impact of this development on biodiversity and to compensate the loss of natural habitats, is expected to alleviate the loss of biodiversity and achieve a 'No Net Loss' of habitats (Wende et al., 2018).
The forest is often affected by the development of the settlement area, as it also implies expanding infrastructure for traffic, energy production, wastewater, etc. (Troxler and Zabel, 2021).Usually, the forest area itself is subject to an original offset regulation provided by forest legislation (Bähr, 2021), which requires forest clearances to be compensated by afforestation elsewhere (compensatory afforestation).As it is the case for offset regulation more generally, such compensation is usually implemented on agricultural land.More recently, suitable land for compensatory afforestation has become scarce, in part because the safeguards for agricultural land were increased.One obvious solution is to replace compensatory afforestation with biodiversity offsets, i. e. nature conservation and revitalization projects outside (or even inside) the forest.In fact, biodiversity offsetting in the forest tends to be cheaper (Pröbstl-Haider and Ammer, 2017) while at the same time decreasing the pressure on the agricultural sector to fulfil compensation requirements.Hence, the demand for more flexible rules will increase as the competition for land between settlements, infrastructure and agriculture intensifies.
The term biodiversity offsetting is used in a variety of discourses reflecting distinct narratives about the effectiveness of respective schemes (Damiens et al., 2020): While some see it as an opportunity for cost efficient nature protection, others rate it as a measure of last resort at the very bottom of the so-called "mitigation hierarchy", to contain damage of otherwise unavoidable development.As referred to above, a more recent interpretation goes even further by emphasizing the priority of avoidance and by committing to the "No Net Loss" goal.
It is well acknowledged that biodiversity offsetting comes with conceptual shortcomings (e.g.assumptions about the commodification of nature; compare Björnberg, 2020) and practical difficulties (Bull et al., 2013).With respect to the latter, key challenges include assessing the equivalency of compensation by an appropriate metric (Borges-Matos et al., 2023) and deciding how much on-site (location) and inkind (habitat) compensation requirements can be loosened to support implementation without endangering the "No Net Loss" goal (compare e.g.Shumway et al., 2023 for a recent example).Reaching the latter, however, would also require a high level of transparency, e.g. by establishing national registers of compensation projects (Kujala et al., 2022), thorough monitoring as well as spatial coordination through planning (Blicharska et al., 2022).Due to these difficulties, it is a real danger that biodiversity offsetting is being subordinated to (settlement) development (Le Billon, 2021) instead of employing it as means to internalize external costs.Accordingly, such offsetting schemes have always been confronted with strong skepticism and opposition since their introduction in the 1960s (Damiens et al., 2020).
In this article, we analyze how stakeholders involved in implementing biodiversity offsetting in the forest as a replacement of compensatory afforestation evaluate different options for balancing flexibility and equivalency at the interface of forest area protection and biodiversity offsetting.Empirically, we focus on the Plateau region of Switzerland, where forest protection and biodiversity offsetting rules are quite rigid despite land-use competition being exceptionally high.This makes Switzerland, and in particular its Plateau region, an important case for studying the resistance against more flexible biodiversity offsetting regulation.Besides serving as an instructive case, this question in itself is of topical interests because the rather rigid rules of offsetting have been rendered more flexible less than 10 years ago, and have since been causing serious implementation difficulties (Schulz et al., 2023).We invited a selection of stakeholders for a one-day workshop to conduct a Q-methodology inquiry that allowed us to elicit preferences based on an exhaustive collection of statements describing policy options.
In the remainder of the article, we will explain how biodiversity offsets and forest clearances are related before we elaborate on the Swiss case in more detail, present the methodological approach and the results, which we will discuss in light of the literature.

Biodiversity offsetting, habitat banking and spatial planning
In theory, biodiversity offsetting is designed to internalize the external costs of biodiversity loss (Damiens et al., 2021), which usually occurs from construction projects on former agricultural land at the urban fringe.At their core, offset regulations, which were introduced with the nature conservation and environmental protection laws in the 1970s, were meant to promote a mitigation hierarchy, which stipulates that project developers first have to avoid negative impacts followed by the prescription to minimize them, i.e. by restoring affected habitats (compare Fig. 1).Obligating the developer to organize and pay for the actual offsetting, i.e. establishing a new and equivalent habitat at a different place that is compensating the ecological loss caused by any (residual) development impacts, is usually only provided as the last resort (Wende et al., 2018).
A prompt or even anticipatory compensation of the same type of habitat (in-kind rather than out-of-kind compensation) very close to the original location (on-site rather than off-site; depicted by offsetting option A in Fig. 1) would probably be most supportive of the "No Net Loss" ambition (Moilanen and Kotiaho, 2018).Such direct compensation is rather difficult and often jeopardized by implementation problems.This is why more flexible approaches are often preferred, although they might come at the cost of a net-loss of biodiversity (compare T. Schulz et al. offsetting option B in Fig. 1).
The offset banking mechanism establishes a third party (a bank operator) who is responsible for collecting offset supply (e.g. a pool of offset areas) and coordinating it with the demand from the side of the developers.While different variants of offset banking exist, they all introduce some flexibility by enabling the offsetting suppliers to establish new habitats for which they receive credits based on an explicit catalogue of compensation measures and respective currencies.Such supply is preferably established ahead of the development project, as this would allow the habitat to accumulate ecological functions until the time the compensation is actually required.Habitat banking can thus provide a critical advantage, as it enables the pooling of offsetting projects (Droste et al., 2022;Vaissière and Meinard, 2021).Although biodiversity offsets can be integrated into spatial planning policies without such an habitat banking mechanism (Hanson and Olsson, 2023), it can largely facilitate the coordination of offsetting areas at a larger scale (Baganz and Baganz, 2023).Therefore, it is also expected that it can help reducing land-use conflicts by providing a better spatial optimization of land-use needs (Tarabon et al., 2021).

Compensatory afforestation and biodiversity offsetting in the forest
Conceptually, biodiversity offsetting is closely related to the requirement to restore cleared forest patches, which is common in many countries (Bähr, 2021).This forest specific type of offset regulation, i.e. compensating forest clearances by afforestation elsewhere (compensatory afforestation), is usually required by forest law.Such afforestation, however, is often implemented on agricultural land also (OECD, 2016, 189f).Agricultural land is thus diminished not only by the settlement area growing at the urban fringe itself but also by the related increasing need for biodiversity offsetting and compensatory afforestation.Ultimately, this raises political pressure to use the forest (and other strongly protected surfaces) as a potential area for biodiversity offsetting (Ecker and Pröbstl-Haider, 2016).
Biodiversity offsetting projects in the forest can be implemented in two different ways: either by designating larger forest patches for ecosystem restoration or biodiversity protection (e.g.forest nature reserves) or by adjusting forest management to allow for "production integrated compensation" (PIC; Druckenbrod and Beckmann, 2018).In the latter case, the offset is accomplished by converting homogenous forest stands towards more structural diversity or a more natural tree species composition, by retaining habitat trees, creating and maintaining valuable open areas, developing rare forest communities, accumulating dead-wood, etc. (Schrader, 2013).Establishing and maintaining such PIC as permanent structures and providing sufficient additionality, i.e. ecological value beyond what would have been provided by the standard management approaches anyway (Heberling et al., 2011), is challenging.et al. (2022) conclude from their global comparison of biodiversity offsetting governance that various basic principles, such as the mitigation hierarchy and habitat banking, are becoming adopted gradually in an increasing number of countries.However, institutional diversity increases due to differing implementation approaches and institutional prerequisites.In Europe, adherence to the mitigation hierarchy -and thus the precedence of avoidance -is still strong in many countries and habitat banking solutions or even compensation fees (Gao et al., 2023) are seen more critically.

Droste
While Germany and the UK might be exceptions, a more cautious approach in Europe is confirmed, for example, for Finland by Lehtiniemi et al. (2023).Analyzing the public discourse at a national level, they find that biodiversity offsetting in Finland is framed 1) by developers and landowners as well as the forest and agricultural administration as a "corporate responsibility", i.e. an opportunity for business, provided sufficiently flexible rules, 2) by "regional governance" organizations as a "planning tool" and thus a set of rules that contain market coordination and 3) by nature conservation organizations, scientific institutions and the public administration as a "nature conservation" tool, provided adherence to the mitigation hierarchy is strict and firm compensation rules and monitoring requirements are stipulated.Damiens et al. (2020) have analyzed biodiversity offsetting discourses more generally across continents based on Dryzek's (2013) comprehensive conceptual account of competing environmental discourses.Apart from more extreme positions, they identify three types of "reformist" discourses that argue for ways to preserve nature without questioning the economic growth paradigm: • "Administrative rationalism" is seen as the original discourse that justified biodiversity offsetting as a last resort measure within a mitigation hierarchy, emphasizing in-kind and on-site measures.
• "Ecological modernization" emphasizes the mitigation hierarchy but still expects positive effects of price signals and thus prefers habitat banking integrated into conservation planning regulation.• "Green neoliberalism" is promoting biodiversity offsetting as a costefficient measure that facilitates win-win solutions, if relying on flexible rules backed by habitat banking.Lehtiniemi et al.'s (2023) "planning tool" discourse can thus be attributed to the "administrative rationalism" type, the "corporate responsibility" discourse to the "green neoliberalism" type and the "nature conservation tool" discourse to the "ecological modernization" type.Conflict is likely to occur between the proponents of such different perspectives on biodiversity offsetting, particularly also since Damiens et al. (2020) argue that the discourses at the extremes have gained in importance.On the one hand, Varumo et al. (2023) observe, e.g. that the implementing actors in Finland are particularly concerned about the acceptance of the results by the broader society, which is likely to contradict ecological requirements of biodiversity offsetting as a "nature conservation" tool.On the other hand, reformist discourses are challenged particularly also by "post-growth" narratives (Damiens et al., 2020) that question biodiversity offsetting as a mechanism that is privileging land development and undermining truly transformative reforms.The complexity of the topic may even provoke conflict among landowners, although they all are likely to share the same "corporate responsibility" frame (Plant and Ruoso, 2023).
One important implication of the complexity of the issue is also, as Karlsson and Karhunmaa (2023) have established for Finland, that policy ambiguity is usually high for such compensation schemes and that it may persist even after a major reform.The authors demonstrate, how this results in a policy experimentation approach, which brings together very different and potentially conflicting implementing actors.They are nonetheless willing to cooperate, to find solutions and to compromise, as they have learned that there is no alternative to biodiversity offsetting and have adopted a more flexible understanding of the mechanism.Given that the introduction of more flexible compensatory afforestation rules in Switzerland had implications for biodiversity offsetting and that implementing actors are still struggling to find a balance between market coordination and planning, as we will explain below, we expect to find a similar situation also in our case.

Case study approach
In Europe, many countries have been reluctant to adopt a more flexible approach towards biodiversity offsetting or even allowing for habitat banking (Brockett et al., 2023;Droste et al., 2022).Switzerland is no exception: The Swiss Federal Nature and Heritage Conservation Act contains an offset regulation clause since 1985.It adheres to a strict mitigation hierarchy and the corresponding implementation guidelines stipulate that in-kind and on-site compensation have strict priority over out-of-kind and off-site compensation (Kägi et al., 2002).An offset banking mechanism and a corresponding explicit eco-points system for assessing the ecological equivalency of compensation projects do not yet exist, so the evaluation of compensation equivalency is conducted in a rather qualitative manner.Thus, biodiversity offsetting rules have been rather stable and remained more rigid than, for example, in neighboring Germany (Epiney and Furger, 2013).
As particularly the lowlands of Switzerland are densely populated and population as well as the settlement area are growing steadily (since 2010, population has grown by about 12 percentage points), the lowland regions and larger mountain valleys experience extreme competition for land (Tobias and Price, 2020).The persistence of a relatively rigid biodiversity offsetting regime under conditions of high land-use competition makes Switzerland an interesting case for studying the development of biodiversity offsetting policy and implementation.Following analytical generalizability (Yin, 2013), we expect our results to be transferable to other cases with similar characteristics in Central Europe, i.e. metropolitan regions in European countries that have not (yet) adopted a habitat banking approach to biodiversity offsetting but that experience high land-use competition.In such contexts political pressure towards more flexible offsetting rules is likely to occur, which is then exacerbated in cases with historically rigid biodiversity offsetting rules, following a multipurpose forest regime.
As Switzerland is a federal country, the specification and implementation of forest policy and biodiversity offsetting is delegated to the level of the cantons (federal states).We hence need to take into account the sub-national level in our analysis.We have selected the Canton of Berne as a 'crucial case' in the Swiss context, which makes it valuable as a single case study (Bennett, 2004).First, the part of the Canton Bern that is situated in the Plateau region is highly urbanized and densely populated and thus representative for the Swiss lowlands.Second, Berne is one of the only regions to have concretely addressed biodiversity offsetting as a means to compensate forest clearances through pilot projects with habitat banking approaches (Schulz et al., 2023).Third, compared to other cantons, the forest administration of the canton of Berne is known for its pronounced advocacy of market-based political instruments and cost-efficient administrative structures (Schmidt, 2018).Such a context is particularly interesting for our focus on the role of the forest sector in land-use conflicts.
Forest area protection is particularly strong and rigid in Switzerland, also: forest clearances are generally prohibited (Art.5 of the Swiss Forest Act) and thus can only be approved by way of exception (Steinmann et al., 2017).To receive such an exception, it has to be shown that no suitable alternative to the designated location in the forest exists for the project causing the clearance, that the clearance is in line with further spatial planning provisions and that it does not cause significant environmental danger.Also, if possible, clearances should be allowed only temporally.
On top of this rather strict mitigation hierarchy, the Swiss Forest Act also explicitly stipulates that all clearances have to be replaced by afforesting land in the same area (Art.7).More recently, pressure from the agricultural sector has resulted in a flexibilization of the rules: as the forest area is actually accruing in the mountainous areas, it was argued that this should be taken into account in the calculation of compensatory afforestation.Since 2016, it is thus possible to offset forest clearances with nature conservation projects (in or outside the forest).While this can be considered the rule where the forest area is accruing (in the mountains) it otherwise (in the lowlands) still must remain the exception (Steinmann et al., 2017).The possibility to replace compensatory afforestation with measures that are not related to forest area preservation, may be seen as a significant departure from strict forest area protection (Bähr, 2021) and the cantonal administration struggles with implementing this aspect and to coordinate it with more general biodiversity offsetting (Schulz et al., 2023).
In recent years, the land-use conflicts affecting the agricultural sector have increased and national legislation was adapted to better protect the most productive agricultural areas (Tobias and Price, 2020).The political pressure to get rid of compensatory afforestation on agricultural land is persisting and corresponding motions have been submitted to the national parliament repeatedly, calling for an even firmer protection of agricultural land.Previous analyses (Schulz et al., 2023) have thus revealed that representatives from agriculture but also developers and other non-primarily forest-related actors involved in implementing biodiversity offsetting (offsetting platforms, private counseling enterprises) tend to support biodiversity offsetting in the forest.

Data collection
In 2020, we invited stakeholder representatives (see below for more detail) to participate in a workshop to exchange opinions on biodiversity offsetting in the forest.The workshop was organized as part of a larger research project on forest-related land-use conflicts and was conducted to bring cantonal and national stakeholders together to jointly discuss policy options for coordinating compensatory afforestation and biodiversity offsetting.The agenda was structured in a way that allowed the Q-methodology surveying approach to be implemented during the workshop.It requires respondents to independently sort statements into a predefined scheme either as part of an online-survey or in private faceto-face sessions.Other than in a more standard survey with "Likertscale" inspired individual answer categories for each item, a respondent should be better able "to provide a model of his viewpoint vis-à-vis the subject matter under consideration; his elicited response indicates what is operant in his case, e.g., that he agrees with statements a and b more than c" (Brown, 1980, 6).Conducting a Q-methodology survey within a workshop-setting has been proposed and implemented by Yoshizawa et al. (2016).They suggest incorporating all necessary steps: the initial generation of statements (the Q set), the individual sorting of this Q set, resulting in a Q-sort per participant, the analysis of the data during the workshop and a grouping of the participants according to the factors found.

Statements (Q-set)
Our workshop did not aim at providing an all-inclusive Q-methodology application.Rather, we considered the workshop format as an advantage to assemble stakeholders from the cantonal (implementation) and national (policy-design) context in order to facilitate exchange based on a structured procedure that would allow us to gather information about positions towards reform proposals.
Preceding the workshop, we sent the potential participants an online questionnaire with a predefined set of 34 statements divided into 17 topics (such as avoidance, forest area preservation vs. preservation of agricultural land, spatial aspects, pooling, compensatory afforestation, temporal aspects, financial compensation, equivalency, habitat banking, enforcement, etc.).These statements represented "policy recommendations" as discussed by Brown (1980, 58ff).The invited participants then had the opportunity to provide comments on the suggested statements, to propose amendments or alternative and new statements or to more generally provide input.We consolidated these suggestions and comments and adapted the statements and their structure, included new statements and discarded others.This procedure resulted in a final list of 34 "policy recommendation" statements, which were not sent to the participants in advance but were presented as the first part of the workshop.Given the elaborate procedure behind the compilation of statements, we are confident that they were fairly comprehensively describing all relevant aspects of compensatory afforestation and biodiversity offsetting in the forest.

Participants (P-set)
19 of the initially invited 25 persons took part in the workshop, who mainly represented stakeholders from Canton Berne such as the cantonal nature conservation and forest administration (including a colleague from the neighboring Canton Aargau, which is equally affected), the cantonal section of a nature protection association, cantonal farmer and forest owner associations as well as consultancy and industry initiatives related to biodiversity offsetting being active in the region.From the national level, the forest and environmental protection administrations and further civil society organizations with expertise on forests were participating (Table B in the appendix).We selected the organizations based on indications given by the cantonal authorities about relevant stakeholders involved in policy design and implementation.Individual invited participants from these organizations were selected also based on what they had published on the subject matter.These participants represented the most relevant interests in the Swiss lowlands context with a specific focus on the canton of Berne.However, it has to be noted that P-sets in Q-methodology do not necessarily have to be representative of the population of relevant stakeholders (Brown, 1980, 191).It is more important that the Q-set (i.e. the statements, as discussed in the previous section) is representative of the public discourse and thus of all possible positions that can be taken on the subject matter.

Workshop procedure
During the initial phase of the workshop, a plenary discussion was held on the consolidated statements.The discussion was necessary to clarify remaining issues with the definition of terms and the ambiguity of statements and thus fostered the shared understanding of the statements.
Later, the participants were grouped into 5 "tables".The participants were allocated to groups by the hosts to avoid clustering participants with supposedly similar beliefs and positions at the same table (Table B in the appendix indicates which representative was sitting at which of these tables).According to the procedures of the Q-methodology, the participants where then given the task to individually lay out the 34 statement cards on a grid that corresponded to a normal distribution over the answer-scale − 4 (strongly disagree) to +4 (strongly agree) and to add justifications for the statements placed at the extremes.
We encouraged the participants to discuss statements in the groups or to also walk around and to discuss statements with others.While this possibility for exchange was actively used, the final Q-sort was done individually in all cases.Due to the workshop setting and the open discussion during the sorting exercise, the Q-sorts may not be fully independent.However, as all of the participants represented a firm interest with respect to clearance compensation, we did not expect them to be influenced heavily by other participants.
The predefined distribution grid for the Q-sorts was perceived as being too rigid for some participants.We thus allowed participants to place the statement cards wherever they pleased within the range of the scale, which corresponds to a "non-forced" Q-sorting procedure.
The sorting exercise lasted for 75 minutes.While the participants were at lunch, the researchers collected and captured the sorts and conducted a preliminary analysis that was then presented to the audience in the afternoon.The participants had the opportunity to discuss these results briefly and then to work on possible solutions and policy recommendations in groups.At the end of the day, these group solutions were discussed again in the plenary which resulted in a more open discussion about caveats and shortcomings of these various reform proposals.

Data analysis
The Q-methodology is completed by a factor analysis of the collected Q-sorts, in which the cases are the statements and the individual Q-sorts (and thus the subjects, i.e. the participants) are the items.Textbooks emphasize that rather than a large sample of participants, a sufficiently large (but more importantly sufficiently representative) set of statements should be provided.With 19 participants and 34 statements, our P-and Q-sets are certainly sufficient (Brown, 1980, 260).An initial statistically significant Bartlett-test (p-value below 0.001) indicates that the data is suitable for factor analysis.
The analysis of the data was conducted with the package «qmethod» in R (Zabala, 2014), using "oblimin" rotation and resulting in three factors.The screeplot (Fig. A in the appendix) indicates that the explanatory power of further factors drops significantly relative to that of the third factor.The factors described in the following sections cluster Q-sorts expressing similar views and thus represent shared perspectives on the subject matter, which were confirmed by the participants during the workshop.The factor loadings of the individual Q-sorts are listed in Table A in the appendix.The table lists only factor loadings above 0.4 and indicates that for most participants allocation to a factor is unambiguous (the more ambiguous cases are discussed further below).Subsequently, z-scores were calculated for each factor and statement, indicating how much a single statement contributes to a factor and thus also giving an indication about whether and how much a statement was supported or rejected by the Q-sorts being attributed to this factor.Whether or not a statement is discriminating a factor is determined by the respective z-scores' distance to the other factors' z-score for a given statement, which is calculated based on a standard-error of differences (Zabala, 2014).
Additional information regarding the reliability of the results, particularly regarding the z-scores estimated, can be obtained by applying a "Bootstrap Q-method" analysis to the data, as is provided additionally by the «qmethod» package (Zabala and Pascual, 2016).First, the bootstrap analysis would allow to identify Q-sorts that do not contribute reliably enough to a factor and thus also to further judge the number of factors to be extracted.This, however, is not recommended with "unforced" Q-sorts, as in our case.The bootstrap also provides standard deviations for the z-score estimates across bootstrap iterations, which allows to further judge the salience of single statements within a factor and to identify those statements that more reliably discriminate between different factors.In the figures of the following section, z-scores for the standard (transparent) and the bootstrap analysis (opaque) as well as the standard deviation for the latter are provided.Reliability is solely judged visibly, based on whether and by how much z-scores deviate and standard deviation intervals overlap.It would also be possible to take into account other criteria, e.g.whether a certain statement changes its factor scores and by how much compared between the standard and the bootstrap analysis (Table C in the appendix).These additional criteria, however, turn out to be of minor importance for the results and aren't further discussed for reasons of space.

Advocates of improving implementation of the status quo
Fig. 2 contains the statements that best separate the first factor (status quo) from the others, (more flexibility and back to in-kind compensation) so the blue squares are always rather distant from the symbols representing the other two factors.
The information contained in the figure suggests that the first factor may be labeled as "Improving implementation of the status quo": gaining back control over the mitigation hierarchy and finding new, innovative ways for biodiversity offsetting also in the forest, without, however, allowing for any kind of offset banking approach.
The bootstrap analysis confirms this interpretation by identifying s26 (support for implementation guidelines) as the most reliably salient statement for this first factor.Other salient and sufficiently reliable statements that support this interpretation include the necessity to first and foremost avoid clearances by intervening accordingly in early phases of the planning process (s1) and orientating compensatory afforestation more generally towards the needs of those species that were affected by the respective clearances (s11) as well as rejecting the idea that the in-kind compensation principle should be given more weight than the on-site principle (s9), a consequence of the latest reform.Also, the complaint that implementation is seen as being hampered by insufficient resources (s27) remains a sufficiently distinguishing statement.
The respondents of this factor form by far the largest group (as can be seen in Table B in the appendix) that contains a broad selection of representatives deemed crucial for implementation: the public administration units of both sectors and levels of public administration, the environmental organizations (which have a right to appeal against development projects) and the national level association of forest owners.

Advocates of more flexible rules
Fig. 3: lists the statements that best determine the second factor and for which the green triangles are farthest from the remaining two symbols representing the other groups.The number of Q-sorts related to this factor is small: they were completed by two representatives of the cantonal farmer association, one representative of a research institution and the representative of the private counseling enterprise (Table B in the appendix).
The statements and respondents attributed to this second factor show that it represents the view of the advocates for a more flexible definition and implementation of biodiversity offsets in the forest.Contrary to the other two groups, the Q-sorts attributed to this factor strongly approve a more market-based coordination of supply and demand.The two statements that are suggested by the bootstrap analysis as the most reliably salient are clearly supporting this interpretation: the group explicitly favors an exchange for balancing demand and supply of offsetting projects (s28) and rejects the integration of potential compensation areas into the cantonal comprehensive plans, the strongest and most explicit planning tool of the cantonal level (s8).
Other distinguishing statements (and respective positions) confirmed by the bootstrap analysis are support for a habitat banking system and the free trading of offsets (s29) as well as for financial compensation into an offset fund (s31) and relative support for expanding the meaning of additionality (s32).Furthermore, rejecting more evidence-based (s21) and qualitative (s23) equivalency verification of biodiversity offsetting as well as a «pooling» of compensation projects (s16) are reliably distinguishing statements.

Advocates of in-kind compensation (afforestation)
Fig. 4 lists the statements that identify the third factor (red dots).They basically indicate a preference for returning to a rule of compensatory afforestation and thus strict in-kind compensation.This group aims to preserve forest surface in a more quantitative sense by strictly adhering to the mitigation hierarchy and favoring command-andcontrol and strict planning measures.
The bootstrap analysis reveals that some ambiguity remains with respect to this factor.Still, the most reliably distinguishing statement (and position, respectively) is rejection of abandoning in-kind compensation even if it were to the advantage of cultivated land and nature conservation sites with high potential (s6).Preference for in-kind compensation even in a different region (s10) and insisting on a permanence requirement for offsets particularly if they were to be coordinated through a habitat banking system (s30), remaining as the probably most critical design and implementation challenge for biodiversity offsetting in the forest, fit this interpretation well, although they are not identified as equally reliable by the bootstrap analysis.
This third group, similar to the second, remained small.Apart from one civil society organization of the forest and one actor from the spatial planning sector, it is particularly one cantonal administration unit that advocates this position.

Participants not unambiguously loading on a factor
It is also telling that some participants couldn't be attributed unambiguously to one single factor.According to our criteria to not consider participants with factor loading below 0.4, it was the representative of the national forest administration and the one representative of a regional forest owners association that were not loading sufficiently on any factors (Table B in the appendix).The federal forest administration, which assumes the lead in the clearance approval procedure, usually tries to take a neutral stance which might explain its balanced position.Forest owners, which often are also farmers, may be torn between strictly preserving the forest area and finding a balanced solution that is also acceptable for agriculture.The divided position of the forest owners is not only reflected by low factor loadings but also by the high loadings of the representative from the cantonal forest owners' association on two factors (Table B in the appendix): apparently, this respondent was undecided between allowing more flexible biodiversity offsetting rules and strengthening compensatory afforestation.

Consensus and disagreement
Two types of consensus statements can be differentiated: those for which the three groups are unambiguously positioned on one side of the origin of the z-score scale and those for which these positions circle around zero.The latter implies agreement due to lack of a strong position, which we interpret as a certain level of indifference.In Fig. 5 it is only statement s24, i.e. the claim that equivalency should only be judged  with respect to the area used, that is clearly (i.e. the result is also confirmed by the bootstrap analysis) rejected by everybody, even by the advocates of more flexible rules.
Fig. 6 lists the three statements, for which disagreement is largest among all three groups and which thus appear to be the most controversial issues.All these three statements obviously reveal conflicts between the advocates of flexibilization and the advocates of strengthening in-kind compensation, while the ones rather supporting the status quo seem to take an in-between position.Prohibiting out-ofkind compensation (s2) is the most controversial claimalso being best confirmed by the bootstrap analysisstrongly rejected by the second group.

Potential coalitions of actors
Apart from the highly contested statements presented in the previous section, this section identifies statements for which some disagreement prevails without ruling out coalitions between two stakeholder groups that both clearly reject or approve a statement.
The clearest potential coalition that is also confirmed by the bootstrap analysis can be derived from s8, s23 and s21 in Fig. 3: a qualitative assessment of equivalency, a proof of effectivity and the comprehensive planning of offsetting areas are aspects that are defended by the supporters of the status quo and the advocates of the compensatory afforestation requirement against those demanding more flexible rules for biodiversity offsetting in the forest.Fig. 7 identifies additional two statements for a potential coalition against more flexible rules: s13 (allowing out-of-kind compensation everywhere) and s14 (strengthening production integrated out-of-kind compensation), although in the latter case, this potential coalition seems to be rather indifferent.Lastly, in Fig. 2 a more salient and reliable potential coalition of the advocates of more flexible rules and those supporting the compensatory afforestation requirement can be identified for statement s26, indicating that only the supporters of the status quo criticize the insufficient implementation guidelines.

Discussion
Our workshop's purpose was to identify stakeholders' acceptance of different options for balancing flexibility and equivalency at the interface of forest area protection and biodiversity offsetting.More specifically, we explored reasons for conflict in relation to biodiversity offsetting in the forest, policy options to reconcile such conflicts, and finally the acceptance of these options.The Q-methodology can be a helpful tool for such an analysis of stakeholder acceptance, particularly in conservation contexts (Zabala et al., 2018).Often, rather obvious opposing stakeholder types are identified by such studies, e.g.resource users vs. conservationists (Hempel et al., 2019) or, in the case of forest management, those preferring management for habitats against those opting for timber harvesting (Steelman and Maguire, 1999).Sometimes, however, conflict rather concerns the rules and institutions structuring decision-making which may superimpose the contrast between utilization and protection interests (Coke and Brown, 1976;Curry et al., 2013;Gruber, 2011).
In the following, we highlight the main insights from our analysis and discuss these in relation to the extant literature on the Q-methodology and biodiversity studies.As our case of Berne, Switzerland exhibits characteristics of relatively rigid biodiversity offsetting following a multipurpose forest regime under conditions of high land-use competition, we argue that following the analytical generalizability (Yin, 2013), our insights can be transferable to other cases with similar characteristics in Central Europe.
A first key insight from the analysis that resonates with the literature is the preference for the status quo, where diverse actors find common ground after a policy reform (i.e. the Revision of the Forest Act in 2016).These advocates of the status quo form the largest group, a "grand coalition" so to say, consisting of an apparently wide variety of very different actors, including nature conservation groups, public forest and nature conservation administration representatives across all levels and the national forest owners among others.This is in line with a similar finding of Karlsson and Karhunmaa (2023) who identify implementing  actors that are willing to find common ground on biodiversity offsetting after a major policy reform which resulted in ambiguity concerning implementation (compare also Evans, 2023, who makes a similar Case for New South Wales, Australia).The remaining two internally likeminded groups are smaller and, with the exception of one representative of a cantonal administration, either do not belong to the inner circle of forest-related stakeholders or are less involved in implementation.The identification of a larger and integrative "implementing coalition" corresponds to similar insights from Q-methodology based stakeholder analyses in comparable contexts.The closest is probably the study by Díaz and van Vliet (2018), who examined stakeholders concerned with the implementation of the recently agreed on Swiss Energy Strategy.They identified the by far largest group as the "mainstream proponents" that agree with the aims of the Energy Strategy.Also, Vanbuel (2022) found two equally large groups of teachers that basically agree with the usefulness of language education policy in Flanders while the remaining groups are more critical.
A second main insight from the analysis is that the "grand coalition" tends to reject market-based solutions to address the increasing difficulty to find suitable land for compensatory afforestation.Together with the more radical advocates of compensatory afforestation, the supporters of the status quo also reject the idea of assessing equivalency through a more formal ecopoints system, a related offset banking system as already applied in the neighboring countries Germany and France (Droste et al., 2022;Schulz et al., 2023) or even to allow for financial compensation.Most prominently, though, they reject out-of-kind compensation, which, according to these actor groups, should either be prohibited or at a minimum should not become the norm.These results confirm that future attempts to make a clearance offsetting system and forest area protection even more flexible will face serious resistance.
On the one hand, it is rather a planning-based approach towards building up "ecological infrastructure" that is promoted.However, our "grand implementing coalition" can't be unambiguously attributed to the "administrative rationalism" discourse type of Damiens et al. (2020), as it doesn't strongly insist on on-site measures.On the other hand, the literature claims that particularly in metropolitan regions with intense land-use competition (Baganz and Baganz, 2023), the right balance between planning approaches and market coordination (Barral and Guillet, 2023) needs to be found.While this is in line with Damiens et al. ( 2020) "ecological modernization" discourse, it doesn't fully cover our implementing coalition either, which rejects a habitat banking approach.
We found that skepticism towards habitat banking approaches is deeply rooted in reservations with respect to the logical consistency and adverse normative implications of the offsetting concept and thus due to serious distrust in the capacity of the efficacy of biodiversity offsetting.This seems to correspond with similar findings about the lacking trust in the problem-solving capacity of certain (market-based) policy instruments hinging on the limited knowledge about their functioning in the Swiss context (Sudau et al., 2023).While this latter result was derived from Q-methodology survey among a large sample of Swiss laypersons, our P-set was limited to invited experts, who are knowledgeable about policy design and implementation with respect to forest area protection and compensatory afforestation.Distrust in our analysis seems to be rooted in experience with biodiversity offsetting regimes, e. g. for the expansion of the network of motorways in the 1970's.This skeptical view is backed by a large body of scientific research also pointing to serious implementation deficits of biodiversity offsetting in different contexts (Damiens et al., 2020).A striking example for implementation deficits is given by Primmer et al. (2019), who demonstrate for the case of Finland, how the state tends to lighten the burden for project developers by taking over tasks and responsibilities.Similarly, Govind (2023) points out, how in New South Wales (Australia) it is difficult to insist on the mitigation hierarchy and the priority of avoidance.
A third insight from our analysis is that there is a strong reservation with respect to out-of-kind offsets.Defining equivalency across different ecosystems remains a challenge that is also reflected in the literature (Moilanen and Kotiaho, 2018).The stakeholders are divided over the question to which extent equivalency should be evaluated by considering primarily the needs of the affected species (implying a more restrictive understanding of equivalency) or whether ecosystem services providing direct benefits for human beings should also be considered (implying a more "holistic" understanding).The former interpretation of equivalency favors the restoration of degraded ecosystems, which has been supported by Weissgerber et al. (2019) and is also supported by the advocates of strengthening compensatory afforestation.One opportunity for reform along this line and against the advocates of the status quo (compare section 4.3) would be to allow afforestation on urban wasteland, as proposed by Lauf et al., (2014).The latter interpretation, instead, promotes so-called "production integrated" biodiversity offsetting measures (compare section 4.6).However, ultimately, we find that in the Swiss context, all hinges on the possibility to provide permanent biodiversity offsets in the forest.If strengthening production integrated compensation in the forest is seen as one reform option, improving their permanence would be a requirement.

Limitations
Certainly, our analysis is not without shortcomings, and it is particularly the workshop character of the analysis that needs to be discussed.First, a vital prerequisite of the method is that the statements employed provide a complete representation of all aspects of the problem.There are many different approaches suggested in the literature, some promoting a fully "theoretical" sample of statements, derived without input by potential respondents and experts while others rely heavily on an inductive generation of statements by the potential respondents themselves.We opted for a middle way, as the limited time during a workshop forced us to collect feedback from potential respondents online and in advance, without the possibility for a more interactive procedure.The workshop format, though, was probably the more limiting factor for the number of statements, as more statements need more time to be sorted.
One additional limitation of the workshop character of the inquiry is the violation of the requirement to collect independent Q-sorts.Table B in the appendix gives an impression about whether there is a coincidence between the grouping of participants at tables and the contribution of their respective Q-sort to one of the extracted factors.Obviously, Fig. 7. z-scores, for each of the three factors, of those cases (statements) for which there is relative disagreement and a coalition of the supporters of the status quo as well as the supporters of compensatory afforestation against those supporting more flexibility seems possible (transparent symbols represent estimates of the standard analysis, opaque symbols represent estimates of the bootstrap analysis, including whiskers to indicate the standard deviation).
T. Schulz et al. the first factor, which, however, comprises the largest group of participants, is clustering somewhat at tables 4 and 5. Otherwise, no such obvious pattern can be observed.We can only reiterate our impression from the workshop that the sorts were conducted by the participants in a responsible way and that all participants were fully self-conscious expert representatives of stakeholder organizations with a firm interest in the issue and with much experience concerning the underlying context.
Another limitation of the workshop format was that it prevented a more personal consideration of the respondents' background information regarding their Q-sorts.We did collect justifications of the most extremely rated statements and respondents were asked to write down their interpretations, qualifications and concerns about statements.This information, however, was not evaluated systematically for the analysis presented above, because most of the more important concerns were expressed in the final discussion of the workshop.
Finally, it is important to note that our inquiry only considered actors that have a strong interest in the subject area and can be considered experts.We have not included the perspective of the broader population on compensatory afforestation and biodiversity offsetting in the forest.One may suspect that well-informed stakeholders are biased towards forest area preservation and less flexibility in biodiversity offsetting as compared to the broader population.However, a recent nation-wide population survey that provided oversampling for the neighboring canton of Aargau (which lies entirely within the Plateau region of Switzerland) reveals that 80% of the population of this canton support strict (i.e.on-site and in-kind) compensatory afforestation (BVU, Departement Bau Verkehr und Umwelt des Kantons Aargau, 2022).While more differentiated questions on this subject area would probably reveal a more nuanced picture, it does not seem that the implementing stakeholders have a more conservative perspective on the issue than the broader population.

Conclusion
Our analysis of the acceptance of policy options to coordinate forest clearance compensation and biodiversity offsetting provides a snapshot of the relevant stakeholder constellations in Switzerland.We thus show that in a context with rigid biodiversity offsetting rules, following a multipurpose forest regime and with high land-use competition, stakeholder preferences impede the integration of habitat banking approaches into the planning of compensatory afforestation and biodiversity offsetting in the forest.Currently, the issue of forest clearance compensation and biodiversity offsetting ranks high on the agenda of implementing authorities of the Swiss lowlands (such as the Canton of Berne) and other implementing actors who are confronted with development pressure and increasing difficulties in finding appropriate land for compensatory afforestation.It must be noted, though, that the sum of affected surfaces is currently still very small (Troxler and Zabel, 2021) and at a national scale, they can hardly be attributed to socio-economic structures and developments (Troxler et al., 2023).Both facts can also be taken as an indication of the effectivity of the rather rigid current rules (Schulz et al., 2023).
The most recent reform has introduced the unique, although limited, possibility to compensate forest clearances with non-forest related offsets.Political pressure from outside the forest sector exists to further loosen these rules to allow for more market-based coordination.Our analysis confirms that the stakeholders concerned with the forest in a narrower sense appear to form an epistemic community that tends towards planning approaches and retaining the current level of forest area protection with the ultimate aspiration to strengthen permanence, to maintain a strict understanding of equivalency and to foster the top of the mitigation hierarchy in order to fend off development pressure from the construction sector.They may best be described as a group that combines elements from the "administrative rationalism" discourse with some of a "green radicalism" discourse, rejecting an "ecological modernization" perspective on opening up the forest area for biodiversity offsetting.
This corresponds to what Damiens et al. (2020) put forward as a transformative understanding that acknowledges the limits of growth and challenges reformist approaches.However, such an approach will depend on strong procedural, i.e. participatory planning approaches, to establish jurisdictional biodiversity targets (Simmonds et al., 2020) and to incorporate the viewpoints of and generating benefits for the community (Griffiths et al., 2019).
We expect the pressure to integrate the forest area into biodiversity offsetting schemes and to combine them with habitat banking approaches to increase in the future, particularly in densely populated metropolitan regions facing intense land-use competition (Barral and Guillet, 2023).Future research could thus employ a comparative approach to examine how shifting discourse coalitions depend on forest preservation traditions and whether and how resistance against biodiversity offsetting in the forest can be upheld.

Declaration of competing interest
The authors declare the following financial interests/personal relationships which may be considered as potential competing interests.

Table A (continued ) s5
To avoid clearances, locations beyond the cantonal borders should be considered s6 Abstain from compensatory afforestation at the expense of cultivated land / high-potential areas s7 Facilitate compensatory afforestation on uncultivated and non-utilized urban land s8 Comprehensive planning of potential areas for offsetting is needed s9 Make compensatory afforestation possible further away (including altitude) s10 Compensatory afforestation in another region is still better than offsetting s11 Implement compensatory afforestation where potential for affected species is highest s12 Structure plans (cantons) should identify areas suitable for compensatory afforestation s13 Out-of-kind compensation should be allowed everywhere s14 Production integrated out-of-kind compensation in the forest needs to be strengthened s15 Agriculture can maintain offsets if objectives and control mechanisms are clear s16 Biodiversity offset pooling institution should secure spatially coordinated offsets s17 Long term maintenance of clearance offsetting requires to adapt the measures and sites s18 Maintaining clearance offsetting more than 50 years causes disproportionate effort s19 Market prices should be allowed for out-of-kind compensation s20 Avoid very expensive and small clearance offsetting measures s21 Equivalence of clearance offsetting needs to be based on a proof of effectivity s22 A system of ecopoints needs to be developed also for the forest s23 Equivalence of compensation needs to be based on a qualitative case assessment s24 Main evaluation criteria for out-of-kind compensation should be the area used s25 Forest owners need to be better informed about clearance offsetting possibilities s26 Clear guidelines from the federal environmental administration are needed to secure equivalence s27 Limited resources of nature conservation impair offset quality s28 An exchange for clearance offsetting should coordinate demand and supply s29 Based on a habitat banking system, clearance offsetting should be freely tradeable s30 A habitat banking system requires an explicit list of permanent offsetting measures s31 Enable financial compensation (offset fund) to prevent uncoordinated micro-offsets s32 Avoiding deterioration of ecosystems should be acknowledged as offsetting measure s33 Compensation premiums/discounts should foster early provision, prevent delay or spatial distance s34 Compensatory afforestation/offsetting should be part of the "ecological infrastructure"

Fig. 1 .
Fig. 1.Principles of biodiversity offset regulation, offset of residual impact and definition of «net-loss» (own representation based on Bennett et al., 2017).

Fig. 2 .
Fig. 2. z-scores, for each of the three factors, of those cases (statements) that best discriminate the first factor (transparent symbols represent estimates of the standard analysis, opaque symbols represent estimates of the bootstrap analysis, including whiskers to indicate the standard deviation).

Fig. 3 .
Fig. 3. z-scores, for each of the three factors, of those cases (statements) that best discriminate the second factor (transparent symbols represent estimates of the standard analysis, opaque symbols represent estimates of the bootstrap analysis, including whiskers to indicate the standard deviation).

Fig. 4 .
Fig. 4. z-scores, for each of the three factors, of those cases (statements) that best discriminate the third factor (transparent symbols represent estimates of the standard analysis, opaque symbols represent estimates of the bootstrap analysis, including whiskers to indicate the standard deviation).

Fig. 5 .
Fig. 5. z-scores, for each of the three factors, of those cases (statements) over which there is relative consensus (transparent symbols represent estimates of the standard analysis, opaque symbols represent estimates of the bootstrap analysis, including whiskers to indicate the standard deviation).

Fig. 6 .
Fig. 6. z-scores, for each of the three factors, of those cases (statements) for which there is relative disagreement without an indication for coalitions of two groups against the other (transparent symbols represent estimates of the standard analysis, opaque symbols represent estimates of the bootstrap analysis, including whiskers to indicate the standard deviation).

Table C
Bias estimates derived from the bootstrapping for all different statements.