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Article

Conservation Fencing for Coastal Wetland Restoration: Technical Requirements and Financial Viability as a Nature-Based Climate Solution

1
River Consulting Pty Ltd., Nietta, TAS 7315, Australia
2
Burwood Campus, Deakin University, Burwood, VIC 3125, Australia
Sustainability 2025, 17(16), 7295; https://doi.org/10.3390/su17167295
Submission received: 4 June 2025 / Revised: 4 August 2025 / Accepted: 7 August 2025 / Published: 12 August 2025

Abstract

This paper investigates whether carbon payments are sufficient to entice private landholders to invest in the rehabilitation and protection of coastal wetlands as a nature-based climate solution. Ecologically intact coastal wetlands, such as mangroves and saltmarshes, are capable of sequestering and storing large amounts of carbon. Reinstating ecological functionality of degraded coastal wetlands may be achieved by installing conservation fences that exclude hard-hoofed domestic and feral animals. This research integrates ecological, technical and economic data to ascertain whether conservation fencing could represent a financially viable investment for coastal landholders in the Australian context, if restored wetlands attracted carbon payments. Data gleaned through literature review and expert interviews about technical fencing requirements, contemporary costs and potential blue carbon income are consolidated into scenarios and tested using cost–benefit analysis. Payback periods are calculated using deterministic parameters. Risk-based cost–benefit analysis accounts for uncertainty of ecological and price parameters; it provides probability distributions of benefit–cost ratios assuming an expert-agreed economic lifespan of conservation fences. The results demonstrate that the payback period and benefit–cost ratio are highly sensitive to wetlands’ carbon sequestration capacity, fencing costs and the carbon price going forward. In general, carbon payments on their own are likely insufficient to entice private landholders to protect coastal wetlands through conservation fencing, except in circumstances where restored wetlands achieve high additional carbon sequestration rates. Policy measures that reduce up-front costs and risk and remuneration of multiple ecosystem services provided by restored wetlands are required to upscale blue carbon solutions using conservation fencing. The research findings bear relevance for other conservation and land-use contexts that use fencing to achieve sustainability goals and generate payments for ecosystem services.

1. Introduction

Coastal ecosystems supply diverse ecosystem services, which are essential to human wellbeing and sustainability [1]. Coastal wetlands, such as mangroves and saltmarshes, have a superior ability to sequester atmospheric CO2 and store carbon and thus play a critical role in climate regulation [2,3]. Land-use conversion and degradation have turned many coastal wetlands into net sources of greenhouse gases [4,5]. Ecological restoration of degraded coastal wetlands can rebuild their capacity to sequester and store carbon [6] and is considered a nature-based solution to climate change [7,8].
Conservation fences play an important role in the restoration of coastal wetlands. Conservation fences are physical barriers that protect the assets contained in enclosed areas from threatening processes and agents [9]. Conservation fences can protect many natural assets, including carbon sinks, biodiversity and water quality [10].
In Australia, many restorable wetlands lie on private land [11,12]. The decision to restore degraded wetlands on private land is strongly influenced by financial considerations [13]. Restoration imposes direct costs (e.g., for fencing, hydrological works, revegetation, etc.) and a suite of opportunity costs; without adequate compensation, participation is unlikely [14]. For wetland restoration to happen at scale, restoration needs to be financially viable for a large number of landholders [8].
In Australia, private landholders can now receive carbon payments from restored coastal wetlands. In 2022, the “tidal reinstatement method” was accredited as a blue carbon method under the Australian Carbon Credit Unit (ACCU) Scheme [15]. Accreditation means that landholders who restore wetlands using this method receive carbon credits. Carbon credits are traded on the carbon market operated through the Commonwealth Emissions Reduction Fund [16], meaning credits yield carbon payments.
A second method for coastal wetland restoration is “exclusion fencing”. Conservation fences in this context seek to achieve the exclusion of ungulates from wetland areas. Ungulates comprise livestock such as cattle, sheep and horses, as well as invasive hard-hoofed mammals such as feral pigs, deer, goats and water buffalo. Ungulates cause damage to wetlands through grazing, browsing, treading, rooting and wallowing [17]. Exclusion of ungulates enables natural or assisted regeneration of wetlands to occur. Conservation fencing targeted at ungulates has been shown to be an effective method for saltmarsh restoration in particular [18,19]. In Australia, “exclusion fencing” is currently under consideration for accreditation as a blue carbon method [20]. If the method is accredited, landholders will also be eligible to receive carbon credits from this blue carbon method.
This research contributes to the international literature by identifying under what conditions the installation of conservation fences for coastal wetland restoration may be financially viable, assuming that carbon sequestered by restored wetlands yields carbon payments. The research articulates how fences need to be designed and managed to effectively exclude ungulates and provides contemporary cost estimates. Cost–benefit analysis integrates cost information and expected carbon income from coastal wetlands for strategically chosen scenarios. Scenarios represent different carbon sequestration rates, different carbon price projections and different cost assumptions. Investment payback periods are estimated, and probability distributions of the benefit–cost ratio are developed using random continuous parameters as model inputs. Conclusions are drawn on how policies and incentives can encourage conservation fencing for blue carbon on private land and encourage upscaling of nature-based climate solutions.

2. Materials and Methods

2.1. Literature Review and Semi-Structured Expert Interviews

A literature review of the scientific and grey literature was conducted to establish the requirements for and costs of effective conservation fencing. Additional information was obtained through semi-structured telephone interviews conducted with fencing experts. Experts were professional fencing business operators. The interviews were non-interventional and were therefore not subject to ethical approval. No personal or business data were collected. Participation in the interviews was anonymous.
A list of businesses of rural fencing professionals in near-coastal locations was compiled using the Australian fencing contractor directory [21]. Of fifteen businesses contacted, seven business operators were available for telephone interviews between 29 and 31 October 2024. The seven experts conducted fencing activities in coastal areas covering eastern Australia, including Tasmania and Cape York. After verbal informed consent to participate in the research was obtained, semi-structured interviews were conducted. Interviews explored technical and cost aspects of fencing coastal wetlands:
  • Technical requirements and fence management requirements for effective ungulate exclusion [22]:
    What types of fences have you used to exclude ungulates from riparian areas and coastal wetlands?
  • Types of costs incurred, cost estimates and variation:
    What is the current approximate cost per km of fence installed?
    What is the approximate cost of levelling and other fenceline preparation methods?
    What additional factors affect the cost of fencing of coastal wetlands?
  • Non-cost factors affecting the financial viability of fencing:
    What is the life expectancy of the fence?
    What other factors need to be taken into consideration?
Interview duration was between 18 and 37 min. Notes were taken during the interviews, and the information gleaned was subsequently consolidated into a cohesive narrative.

2.2. Cost–Benefit Analysis

To gauge the economic opportunity provided by the proposed “exclusion fencing” blue carbon method, cost–benefit analysis was conducted. Cost–benefit analysis encompasses comparing the projected costs and benefits associated with an investment decision to determine whether the investment yields a financial net benefit [23]. Cost–benefit analysis was used to estimate the benefit–cost ratio (BCR) and the payback period of investment for strategically selected scenarios. Cost–benefit analysis considers an investment economically viable when BCR ≥ 1. At the point where BCR = 1, the internal rate of return of the investment is equal to the discount rate. Higher BCR estimates indicate that the internal rate of return is higher than the discount rate, meaning the investment is more profitable. For infrastructure projects such as fencing, the payback period of investment assesses how quickly BCR ≥ 1 is achieved [24]. Shorter payback periods are preferable. For a fencing project to be financially viable, the payback period needs to be shorter than the economic lifespan of the fence.
The premise of this cost–benefit analysis was twofold. Firstly, it assumed that exclusion fencing of degraded coastal wetlands would enable functional restoration of coastal wetlands, which would subsequently achieve their blue carbon potential. Secondly, it assumed that all carbon sequestered by restored wetlands would be remunerated through the sale of carbon credits.
Risk-based cost–benefit analysis was used to account for uncertainty associated with potential future income generated by exclusion fencing. Risk-based cost–benefit analysis assesses probabilities of outcomes [25]. By defining key parameters as random continuous variables, probability functions of the BCR were obtained [26,27]. The carbon sequestration rate following wetland restoration and the annual increase in the carbon price were treated as random continuous parameters. Probability functions of parameter values in scenarios exploring uncertainty were obtained using 1000 Monte Carlo Simulations (MCSs). This simulation number is in the range of 500–1000 simulations recommended for statistically stationary models [28]. Dobes et al. [29] used risk-based cost–benefit analysis of fencing for water quality improvement, while Hagger et al. [30] applied the method to assess the viability of tidal reinstatement of coastal wetlands. The cost–benefit analysis was conducted in Microsoft® Excel® for Microsoft 365 MSO (Version 2507). The specifications of parameter distributions in any given scenario are given in the Results section.
The BCR achieved by the investment in conservation fencing was calculated as the ratio between the net present value of anticipated blue carbon income (NPV_I) from the protected wetland at a specified point in time and the net present value of costs for fence installation and maintenance (NPV_C) at the same point in time:
B C R t =   t = 0 t N P V _ I / t = 0 t N P V _ C  
Costs consisted of up-front material, machinery and labor associated with fence installation, and ongoing fence maintenance costs. Income was defined as the wetland’s carbon sequestration rate (CSRt ≞ t CO2e ha−1 yr−1) multiplied by the wetland area protected by the fence (A ≞ ha) and the carbon price (CPt ≞ AUD/t CO2e). A discount rate r = 6% was applied to future income and expenses.
N P V _ I t = A × C S R t × C P t / 1 + r t
The first set of benefit–cost scenarios gleaned the expected payback period of investment in exclusion fencing under different cost and carbon sequestration assumptions. Parameters were treated as deterministic.
The second set of risk-based benefit–cost scenarios estimated the BCR of exclusion fencing under uncertainty. These scenarios explored the financial risk associated with investment in exclusion fencing. To capture uncertainty, ‘carbon sequestration rate’ and ‘annual carbon price increase’ were modeled as independent random variables. Both were defined as having a normal distribution ~N( μ 2) with mean value μ and standard deviation σ.
The specification of CSR as a normally distributed random continuous parameter is:
f C S R t =   1 / σ     ×     2 π     ×     e C S R μ 2 σ 2 2
The carbon price was assumed to be increasing, with the annual rate of the price increase (cpi) being uncertain:
f c p i t =   1 / σ     ×     2 π       ×     e c p i μ 2 2 σ 2
This assumption was based on past performance of the carbon price, which shows a general trend of price increase since the inception of ACCUs but high price volatility [31]. The effect of defining carbon price increase as a random continuous variable is illustrated in Figure 1 for cpi~N(μ = 10% yr−1, σ = μ) and a starting price of 35.50 AUD/t CO2e, which was the ACCU price applicable on 6th May 2025. In comparison, the price had previously exceeded 40 AUD/t CO2e in November 2024 [32].
Under the stipulated uncertainty, there was a 50% probability of the nominal carbon price being in the range between 44 and 67 AUD/t CO2e after 12 years. There was a 5% probability of the future nominal carbon price experiencing a decline to AUD 31 after 12 years and a similar probability of it exceeding AUD 90 after 12 years. For each scenario under investigation in the risk-based cost–benefit analysis, the assumptions defining the parameter uncertainty are stipulated.

3. Results

The first research objective was to compile and articulate the requirements regarding construction, maintenance and management of conservation fences, which effectively exclude ungulates. The insights gleaned from the literature review and expert interviews are summarized below using subheadings and bullet-point lists for brevity and clarity.

3.1. Effective Exclusion Fencing

3.1.1. Fence Types

Conservation fences for coastal wetlands are barrier fences. They are intended to keep out ungulates. Exclusion of ungulates can be achieved through a variety of fence types, with different solutions applicable in different circumstances. Principally, there are three fence type options:
  • Mesh netting is a prefabricated wire mesh that is quick to erect and acts as a physical barrier to domestic, feral and native animal movement. Mesh netting comes in a variety of heights and with different mesh openings. Mesh openings tend to be graduated, with larger holes higher on the mesh and smaller holes towards the bottom of the mesh. Mesh netting can come with a skirting or ‘apron’, which lies flat on the ground and is designed to stop animals from digging underneath. High-tensile plain wire is often added above mesh netting to support the fence strength. Mesh fencing requires high-tensile plain support wire wherever the fence spans over waterways.
  • Barb wire fences consist of multiple strands of twisted barbed high-tensile wire. The barbs embedded in the wire are sharp, deterring animals from pushing up against the fence or rubbing against it. Cattle fences typically consist of 5–7 strands of barb wire.
  • Electric fencing uses plain wire carrying an electric current, which induces avoidance behavior in animals. Electric fences need to be continuously charged to between 5000 and 10,000 volts to prevent animals from touching the wires. This requires an adequate and reliable power supply. Electric fences are typically arranged as multiple strands of plain wire; some carry electricity, while the other strands act as earth wires. Electric fences are cheaper to build than mesh netting fences but are less effective in situations where vegetation growth impacts reliability of charge; they also require more monitoring effort [33]. Adhering to principles of safe operation, e.g., through the installation of warning signs, is paramount where people may interact with electric fences [34].
  • Electric fences can be combined with mesh netting or barb wire fences. This increases the effectiveness of the fence but also increases costs.
Fencing wires and netting require regular posts to hold them up and strainer posts and stays to tension the wire. Fence posts are typically spaced between three and five meters apart. The material of fence posts is typically treated timber or rot-proof native timber if it can be sourced locally. Timber posts are unsuitable for rocky ground; here, post holes may have to be pre-drilled and posts concreted to affix them to the ground. Stainless steel is the most durable material in highly corrosive coastal environments. Insulators or insulator posts are required to hold electric wires in place.

3.1.2. Matching Fence Type to Ungulates

Conservation fences seeking to prevent the movement of animal species must be designed with the physical characteristics and abilities of the target species in mind, including their size and ability to jump, dig, climb and bite through different fences [10]. The behaviors of species, e.g., whether they dig under, push through or jump over, determine design characteristics of the exclusion fence.
Key design aspects are the height of the fence, type of wire and layout of the fence. Table 1 provides an overview of ungulate-specific fence design recommendations.
Among ungulates, deer, goats and pigs have the most demanding requirements [35,36,37,38]:
  • Deer can jump high fences. Where deer are to be excluded, extra fence height is required, with a minimum height of 1.8 to 2.0 m recommended. Maximum mesh size is 300 × 200 mm for red deer (Cervus elaphus) and 200 × 200 mm for fallow deer (Dama dama) [39].
  • Feral goats can pass over, through or under fences. Fence height recommendations range from 1.1 to 1.3 m. External diagonal bracing posts should be avoided as they assist goats in climbing over fences. Mesh size of 150 × 150 mm is deemed adequate. Any gap between the ground and fence should be no more than 80 mm. A strand of barbed wire at the bottom of the wire mesh is recommended to prevent goats from pushing under the fence. Fences with aprons are also suitable.
  • Feral pigs preferably pass through or dig under fences. Fence height recommendations vary from 0.9 to 1.2 m. Posts should be no more than 5 m apart. Mesh fence with aprons is recommended. Pigs will seek to break through fences, in particular, if a high-value food or water resource is on the other side [38,40].
  • Water buffalo are prevalent across coastal areas of the Northern Territory. Fences designed for cattle are suitable for buffalo; fences need to be well maintained as buffalo tend to tackle sub-standard fences with their horns.
In Australia, at any given location, one can expect the presence of multiple ungulates. An ungulate-proof fence therefore “must include a mesh size to exclude the smallest species, a fence height to exclude the most agile jumper or climber, and have the material strength to withstand the most powerful species” [37]. Guidelines for riparian fencing are highly relevant in the context of coastal wetland fencing [41], as are detailed guidelines for exclusion fencing [42]. Fence manufacturers also provide detailed technical explanations, specifications and illustrations of their products (e.g., [43,44,45,46]).

3.1.3. Measures Supporting the Effectiveness of Exclusion Fences

Key measures supporting the effectiveness of fences include fenceline siting and preparation, fence monitoring and repair and ongoing management of the protected area. The latter refers specifically to the initial removal of ungulates from the protected area and ongoing removal of ungulates that may stray into the area.
Soil type and environmental conditions influence the type of post materials to be used. For example, steel posts may be required for rocky areas, and post holes may have to be predrilled for wooden posts. In sandy and soft soil, extra-long posts may be required to ensure fence stability. Hot-dipped galvanized steel is significantly more durable than untreated structural steel and only slightly more expensive. In wet and saline conditions, the corrosion resistance of stainless steel ensures superior longevity but at four to five times the cost [47].
Fenceline preparation is essential. Prior to fence installation, a corridor needs to be prepared for the fenceline and to facilitate access. Fenceline preparation requires various amounts of land clearing and leveling, to regulate the distance of the bottom fence wire from ground level. “Effective exclusion fences rely on well-prepared and graded fence lines, with no dips or hollows, and a wide cleared area on either side, to reduce damage from branches, improve fence visibility and access for maintenance” [42]. General recommendations also include the removal of platforms (rocks, stumps) on the outside of the fence that may act as a platform for ungulates to jump the fence. Tree branches overhanging the fence should be removed to prevent foreseeable damage to the fence. There are state-specific guidelines that govern the clearing of native vegetation for this purpose.
Monitoring and maintenance are paramount for the long-term effectiveness of a newly constructed ungulate-proof fence [33]. “A good maintenance and monitoring program will detect the breach immediately upon its occurrence, will have people and resources in place to make emergency repairs, and will have reduced the likelihood of animals entering when a breach occurs” [48]. When damage to a fence occurs, e.g., through tree fall, flood damage or animal impact, it needs to be swiftly repaired. Once a fence is compromised, ungulates—especially pigs—have been found to quickly reinvade and cause the same level of damage, or potentially worse damage, as if the fence did not exist [49].
Ungulates need to be eliminated from protected wetlands after an exclusion fence is first constructed; thereafter, an ungulate-free status needs to be maintained. On typical coastal farms in south-eastern Australia, removal of stray farm animals from protected wetlands does not pose a particular problem. Removal of feral ungulates may be more problematic, specifically in large wetland areas [37]. Depending on the species and the size of the wetland area, ungulate removal techniques may include aerial shooting, ground hunting and trapping [50]. Removal may possibly include poisoning of feral pigs [38]. Though controversial, aerial shooting remains the key control tool for managing, in particular, water buffalo, feral horses and feral deer in Australia [51,52].
Exclusion fences have ‘weak points’ where people access or transition fences [33]. Open gates facilitate ungulate incursions. Installing cattle grids instead of gates can mitigate against this risk, but grids are more expensive to install. Damage to fences can be caused by animal interaction with the fence, vandalism or natural events such as floods and windstorms. Fences also deteriorate over time, particularly in saline coastal conditions and if poorly maintained.

3.2. Factors Impacting the Efficiency of Exclusion Fencing

The second research objective was to explore what factors determined the efficiency of ungulate exclusion fencing. This section explores cost-effectiveness within ecological, social and economic constraints [53]. For private landholders, the decision to implement fences is strongly influenced by the expected return on investment [54]. The following question thus arises: under what circumstances would it be efficient for landholders to invest in conservation fencing of coastal wetlands, if this generated income from carbon credits issued for protected wetlands? To be economic, at a minimum, income from carbon credits earned by the protected wetland would have to off-set the cost of exclusion fencing within the economic lifetime of the fence. The economic lifetime of the fence is the anticipated number of years after fence construction, before major repairs and associated costs can be expected.

3.2.1. Monetary Benefits from Blue Carbon

The financial benefit of ungulate exclusion fencing can be quantified as the ACCUs issued for the area protected, multiplied by the ACCU price (Equation (2)). The number of ACCUs depends on the amount of carbon sequestered and stored by the wetland.
Establishing the ability of coastal wetlands to sequester and retain carbon is the focus of much contemporary research [55,56,57,58,59]. Estimates of CSR differ for different types of coastal wetlands, and there is high variability within the estimates for each type of ecosystem. International research indicates that mean saltmarsh CSR is 8.0 t CO2e ha−1 yr−1 with a standard deviation of 8.5 t CO2e ha−1 yr−1 [60]. In the Australian context, estimates for saltmarsh CSR range from 1.17 t CO2e ha−1 yr−1 in temperate Western Australia [61] to 2.01 t CO2e ha−1 yr−1 in temperate Victorian locations [62] and 9.3 t CO2e ha−1 yr−1 for tropical locations [63].

3.2.2. Monetary Cost of Fencing

Installation of an exclusion fence is a non-trivial and expensive activity. There are initial capital investment costs and ongoing costs after the fence is erected. Total costs comprise different cost categories:
  • Groundwork is necessary to facilitate access for fence construction and, in the case of mesh netting, ensure gap-free placement for maximum fence effectiveness.
  • Material per-meter costs are principally determined by the choice of the fence type and configuration. Netting and wire, posts and strainers are major components of the material cost aspect. Additional material costs are incurred for gates, cattle grids and swing netting required for waterway crossings.
  • Installation costs comprise labor costs for the crew of people installing the fence and the costs for specialized machinery hire and cartage, if required.
  • Maintenance costs are associated with regular inspections performed to identify any damage or breaches and repairs to reinstate fence effectiveness. Vegetation management may be required to retain access to the fence and prevent potential damage to the fence.
  • Costs may be associated with the initial removal of ungulates from protected wetlands. Repeated removal of domestic and feral ungulates straying into the protected area is essential.
Cost estimates for exclusion fencing in the literature are rare and case-specific. For example, Reef Catchments [64] puts the cost of installing one km of permanent mesh pig exclusion fence at approximately AUD 18,000 km−1 with an additional annual fence maintenance cost of 2% of construction cost (AUD 360 km−1 yr−1). Other sources suggest that the material costs for rural fences can be between AUD 60 to AUD 80 m−1, with prices potentially rising to AUD 150 m−1 when installation is difficult [65]. Dickman [10], over a decade ago, estimated the material cost of conservation fencing to be between AUD 6000 and AUD 30,000 km−1, with cost differences based on fence configuration, location, substrate and topography.
Pertinent cost information obtained from semi-structured interviews conducted with fencing experts is summarized in Table 2. As a guideline, per-km fencing costs were estimated to be in the range of AUD 20,000 to AUD 50,000, and experts agreed that in coastal conditions, the economic lifetime of an exclusion fence—and consequently the investment payback period—was 10 years.
The perimeter-to-area ratio of a conservation fence directly affects its financial efficiency. Small ratios are preferable as perimeter reflects fence length and therefore cost, while the size of the area enclosed determines income [53,66,67]. The ratio is determined by the shape of the conservation area, with square or rectangular-shaped areas offering more favorable perimeter-to-area ratios compared to irregular-shaped areas. Square shapes are ideal; a square 1ha wetland area requires only 400 m of fenceline. In comparison, the equivalent rectangular-shaped area may require 500 m of fenceline, resulting in a 25% higher cost for the same benefit. Irregular shapes further reduce the efficiency of investment in fencing.
Even with efforts to minimize the perimeter-to-area ratio, siting a conservation fence is ultimately dictated by the shape of the wetland and the terrain surrounding it. Straight lines following ridgelines or along roadsides are preferable. Straight lines are easier to construct than lines with many corners; they are more effective (as they can be more highly strained) and more easily maintained. Where possible, fences should be located out of flood zones, especially where there is likely to be fast-flowing water that could damage the fence [41,68].

3.2.3. Additional Considerations About the Benefits and Costs of Ungulate Exclusion Fences

This research focuses on the private financial costs of exclusion fencing relative to the anticipated income from carbon credits; any other benefits and costs associated with conservation fences are not considered in the cost–benefit analysis. They are, however, relevant in a broader socio-economic and environmental context and thus warrant mentioning. In particular, wetlands provide a multitude of ecosystem services that not only benefit landholders but also spill over to benefit society as a whole [69].
The ‘total economic value’ framework conceives the totality of ecosystem services provided by natural assets such as wetlands through the lens of use values and non-use values [70]. For any given wetland, use values can encompass extractive uses such as fishing or angling and non-extractive uses such as bird watching. Non-use values include climate regulation, aesthetic value and existence value. The installation of ungulate exclusion fences is likely to enhance all ecosystem services provided by coastal wetlands and thus generates benefits across multiple use and non-use values.
Wetlands hold particular significance for indigenous peoples [71]. Many wetlands have significance as ceremonial and initiation sites and traditional hunting and gathering grounds, and wetlands may also serve as boundary markers [50]. Groom et al. [72] explored the sociocultural values of the extensive coastal wetlands in the Northern Territory. Here, the majority of coastal and near-coastal land is owned, managed or co-managed by Aboriginal people. Benefits from coastal wetland improvement accrue to Aboriginal communities in the first instance [73]. Many ungulates have invaded coastal wetlands and are causing extensive environmental damage. This includes feral pigs, cattle and goats, buffalo, horses and donkeys (Equus asinus). Ungulate exclusion fences can safeguard important cultural assets and food sources.
However, ungulates also hold a variety of cultural, spiritual, financial and food values for traditional owners [50]. For example, the Jawoyn people reportedly consider buffalo a source of bush meat and horses a bush pet, resulting in a preference for retaining these species in the landscape. In contrast, they regard pigs as a pest species, which they want eliminated [74].
Wellbeing benefits to traditional owners from exclusion fencing projects are maximized when such projects deliver ongoing sociocultural benefits, including employment benefits and associated income. Activities including fence maintenance and ungulate tracking, removal and culling present an employment opportunity for remotely located traditional owner communities. Income earned from the provision of such environmental services has been shown to make a large positive contribution to their wellbeing [75,76,77].
Exclusion fences can have unintended impacts on non-target species; they cause entanglement, present barriers to movement or migration, and can cause behavioral change [38,78]:
  • Flying and gliding fauna, e.g., bats and gliders, are particularly prone to becoming entangled in barb wire. For this reason, the use of plain top wires is recommended and, according to the fencing contractors, used in most conservation fences.
  • Fences present barriers to the movements of non-target species. Fences can disrupt migration patterns of native fauna and cause behavioral change. Fencing contractors reported options for installing ‘gates’ in the fence or pieces of poly pipes below the fence to facilitate the movement of small native fauna such as fish, platypuses and turtles [79]. However, no similar solutions exist for larger marsupials and dingos.
  • Fences per se do not reduce the populations of ungulate pest animals. Fencing one area can result in increased grazing pressure and impact in other areas.
Measures for minimizing negative ecological impacts need to be considered in the planning, design and implementation phases of ungulate exclusion fencing.

3.3. Payback Time for Investment in Exclusion Fencing

This section reports the results of applying deterministic cost–benefit analysis for evaluating the attractiveness of exclusion fencing using the payback method [24]. Payback period is the time it takes to achieve BCR = 1, i.e., for the net present value of carbon income to be equal to the net present value of cost.
Fencing incurs up-front costs for materials, machinery and labor, and ongoing costs for maintenance. Potential carbon income only accrues after fences are installed. As explained in Section 3.2.2, experts stipulate the economic lifetime of an ungulate exclusion fence in coastal conditions to be 10 years. Consequently, only situations that achieve BCR ≥ 1 by year 10 are deemed financially viable.
Three cost scenarios and three CSR scenarios are explored. Figure 2 illustrates the results. Assumptions applied in all scenarios are as follows: Annual maintenance costs of 2% of installation costs apply to cover labor costs associated with regular inspection, minor repairs and occasional ungulate removal. The carbon price increases at 5% yr−1. The perimeter-to-area ratio assumes that 0.5 km fenceline is required to enclose 1 ha of wetland.
The three CSR scenarios shown in Figure 2a represent the saltmarsh carbon sequestration estimates given in the literature, ranging from 2 t CO2e ha−1 yr−1 [62] to 9.3 t CO2e ha−1 yr−1 [63]. A further scenario of 5 t CO2e ha−1 yr−1 is included. The cost of fencing is assumed to be AUD 30,000 km−1.
Scenario CSR = 9.3 t CO2e ha−1 yr−1 achieves cost payback in year 5. This scenario achieves BCR > 2 after 13 years. In contrast, in the scenario with a low sequestration rate, CSR = 2 t CO2e ha−1 yr−1, BCR remains <1 for the entire 25 years shown. In the middle CSR scenario, payback is achieved in year 12, which is just outside the 10-year target range.
The three cost scenarios in Figure 2b represent typical fencing cost stipulations provided by fencing experts: AUD 20,000, AUD 30,000 and AUD 50,000 km−1 for different types of material requirements depending on ungulates to be excluded, difficulty of terrain and types of materials used. Assumed CSR in these scenarios is 5 t CO2e ha−1 yr−1.
As already shown, the combination of AUD 30,000 km−1 and CSR = 5 t CO2e ha−1 yr−1 results in cost payback after 12 years. If the fence installation cost is AUD 20,000 km−1, the payback period is reduced to seven years. This low-cost scenario achieves BCR > 2 in year 13. High installation costs of AUD 50,000 km−1 see the payback period extended to beyond 20 years.
This means that, ceteris paribus, fencing costs below AUD 30,000 km−1 combined with carbon sequestration rates greater than 5 t CO2e ha−1 yr−1 are likely to achieve cost payback within the economic lifetime of ungulate exclusion fences protecting coastal wetlands.

3.4. BCRs Under Uncertainty

In reality, landholders need to make the investment decision—whether or not to invest in installing a conservation fence around a coastal wetland—under risk. The question thus becomes what the likelihood is that carbon credit payments will pay back the investment within the 10-year economic lifespan of the fence.
The following scenarios show probability functions of the BCR for uncertain future carbon price (as illustrated in Figure 1) and uncertain CSR achieved by the protected wetland. Probabilities are modeled by applying 1000 MCSs, as explained in Section 3.1.
Figure 3 depicts the probability curves for BCR in year 10 for different CSR levels.
Under assumptions of low carbon sequestration (CSR~N(μ = 2; σ = 1 t CO2e ha−1 yr−1)), there is a zero probability of cost payback after 10 years and a 50% probability of paying back 50% of fencing cost after 10 years.
In scenario CSR~N(μ = 5; σ = 3 t CO2e ha−1 yr−1), the probability of payback within 10 years is 76%. This means that cost payback is probable, but not guaranteed. There is a very small (2%) probability of achieving BCR ≥ 2.
In scenario CSR~N(μ = 9; σ = 5 t CO2e ha−1 yr−1), cost payback is certain to be achieved after 10 years. This scenario has a 65% probability of BCR ≥ 2 after 10 years, a 12% likelihood of BCR ≥ 3 and a 1% likelihood of BCR ≥ 4. This scenario is highly profitable.
The results indicate that, ceteris paribus, conservation fencing of tropical saltmarsh wetlands is financially viable. However, for low-CSR wetlands in temperate locations, the case for investment in conservation fencing is not favorable.
Fencing costs are up-front costs and thus not subject to future uncertainty. Maintenance costs over the 10-year economic lifespan of the fence are also predictable, assumed at 2% of installation cost per year, as no major repairs are expected. However, it is still important to explore how uncertainty of CSR and future carbon price affects the BCR of different levels of fencing cost. The same three levels of fencing cost as previously (Section 3.3) investigated for deterministic conditions are applied.
Figure 4 illustrates the estimated probability distribution for the BCR after 10 years for the three cost scenarios. Assumed carbon price uncertainty is ~N(μ = 5% yr−1; σ = μ). Assumed CSR is given by ~N(μ = 5; σ = 3 t CO2e ha−1 yr−1). Each scenario modeled independent probability distributions for CSR and cpi using 1000 MCSs.
Under the given assumptions, there is a 98% probability of cost payback (i.e., BCR ≥ 1) after 10 years in the AUD 20,000 km−1 cost scenario. This scenario is associated with a 39% probability of BCR ≥ 2 and 3% probability of BCR ≥ 3 after 10 years.
Probability of cost payback after 10 years for the AUD 30,000 km−1 cost scenario is 76%. This means there is a 24% likelihood that cost payback will not be achieved within the economic lifetime of the exclusion fence.
Probability of cost payback after 10 years for the AUD 50,000 km−1 cost scenario is 12%, meaning it is unlikely but not impossible for exclusion fencing to be viable under the given combination of assumptions.
As previously stated, Australia’s temperate zone saltmarshes have estimated sequestration rates of 2 t CO2e ha- yr-1 [62]. Many of these wetlands are privately owned [12], and upscaling private wetland conservation requires that the associated investment is financially viable. The estimated BCR for conservation fencing of such low-CSR wetlands, deterministic and probabilistic, has not been supportive of investment. The question of whether more favorable fencing costs and carbon price assumptions may result in favorable BCRs arises.
Three additional scenarios are investigated; two assume more favorable carbon price development under uncertainty, and one explores very low fencing costs. Figure 5 illustrates the resulting BCR probability distributions. The carbon price scenarios assume 10% yr−1 and 15% yr−1 mean annual price increase, respectively, normally distributed across the 1000 MCSs, with σ = μ. The higher level of price increase represents a more optimistic outlook for the carbon price, but also a riskier one. In these scenarios, fencing costs are assumed to be low, at AUD 20,000 km−1. The third scenario represents very low fencing costs of AUD 10,000 km−1. Such low costs may apply where only domestic grazing animals such as cattle, sheep and/or horses are excluded from wetlands, and where existing fences can be retrofitted to ensure effective exclusion.
At low fencing costs of AUD 20,000 km−1, there is a 32% probability of cost payback after 10 years if carbon price development is uncertain with cpi ~N(μ = 10% yr−1, σ = μ). More favorable cpi ~N(μ = 15% yr−1, σ = μ) increases the likelihood of cost payback within 10 years to 71%. This means that even very high carbon price increases in the near future do not guarantee cost payback in low-CSR situations.
In the scenario that reduces fencing costs to AUD 10,000 km−1, likelihood of cost payback after 10 years is 99 percent for the cpi ~N(μ = 10%, σ = μ) scenario. This suggests that low fencing costs are the key to viable conservation fencing of low-CSR wetlands. This result can be explained by up-front costs influencing the BCR relatively more strongly than rising future income, which is discounted.

4. Discussion

This research gauges the economic opportunity offered by blue carbon payments for protecting coastal wetlands through conservation fences. Conservation fences are designed to exclude ungulates and thereby prevent physical and biological disturbance of wetlands. Deterministic and risk-based cost–benefit analysis are applied. The exploration is hypothetical and general in nature, and multiple assumptions apply.
The premise of the cost–benefit analysis consists of three parts. Firstly, it is assumed that installing conservation fences around degraded coastal wetlands will enable functional restoration, and wetlands will subsequently achieve their blue carbon potential. In reality, full recovery of carbon sequestration may take decades to achieve [8]. Secondly, it is assumed that all carbon sequestered by protected wetlands is remunerated through the sale of carbon credits. This premise is also optimistic in that ACCUs are issued subject to additionality conditions [80,81]; only carbon sequestration deemed ‘additional’ to what would have occurred without fencing is remunerated. Further matters affecting profitability and risk of conservation fencing for blue carbon include definitions of property rights and determinations regarding leakage and permanence [82].
By combining literature research and expert interviews, this research achieves a systematic and comprehensive depiction of factors determining both the effectiveness and efficiency of ungulate exclusion fencing. Fencing is a vital element of many conservation activities, whether the primary objective is biodiversity conservation, water quality protection or carbon sequestration. Fencing is a seemingly banal conservation activity; however, there are many factors to consider in the siting of fences, fenceline preparation, choice of fence type and materials, and determination of how to deal with ‘weak points’, all of which determine fence functionality and cost. The up-to-date compilation of costs is useful for other researchers who seek to assess the financial net benefits of conservation measures or land-use options involving the installation of fences. Recently used fencing cost estimates of AUD 15 m−1 [18,83] refer to the pre-COVID-19 era. Using outdated data leads to the underestimation of costs and, consequently, overestimation of the financial viability of natural carbon solutions based on “exclusion fencing”.
The results illustrate that conservation fencing for blue carbon may present a viable, even lucrative, investment option under certain circumstances, specifically in the case of wetlands with high carbon sequestration potential [84]. In contrast, for wetlands with low carbon sequestration potential, income from blue carbon alone is unlikely to pay back the investment in conservation fencing in most situations during the economic lifetime of the fence. Similar findings were made for saltmarshes in Scotland [85]. For wetland protection to be financially viable in such situations, landholders require additional incentive payments [86]. Additional payments may take the form of grant payments that reduce the up-front cost of fencing and/or additional remuneration for other ecosystem services provided by protected wetlands, such as biodiversity improvements or recreational opportunities [87,88]. Remunerating multiple ecosystem services is called ‘bundling’ or ‘stacking’ [89]. Programs that support sustainable livelihoods for traditional owners by remunerating social co-benefits of wetland restoration and protection also exist [90].
The research identifies cost minimization as a key strategy for ensuring financial viability of investment in conservation fencing, specifically where income potential from resulting ecosystem services is limited. A key factor determining viability is the perimeter-to-area ratio of the conservation fence; the more irregularly shaped the protected area is, the wider this ratio becomes, resulting in reduced viability. Minimizing the ratio is a key consideration when siting a fenceline.
When interpreting the results of the cost–benefit analysis, it is further important to note that any other costs associated with conservation fencing for blue carbon were considered outside the scope of this analysis. Additional costs reduce the BCR and increase the payback period and consequently negatively affect the financial viability of conservation fencing. Additional private costs may arise, for example, in the form of opportunity costs from lost income. This is particularly the case where saltmarshes were previously used for agricultural production, e.g., cattle grazing. Removal and eradication of ungulates from fenced wetlands may incur significant costs in some circumstances [91]. There are also transaction costs to consider when participating in carbon sequestration programs, e.g., brokering costs associated with the project being managed by specialized companies [92], with brokers and traders typically charging between 5 and 20% share of carbon credits as commission.
Risk-based cost–benefit analysis yields probability distributions of financial parameters. Probability distributions enable decision-makers to assess probabilistic outcomes of investment decisions within the realm of their business situations and individual risk preferences [93]. For example, a risk-taking landholder may want to invest under conditions that estimate 75% probability of cost payback while also offering a 20% chance of BCR ≥ 1.5. A risk-averse landholder may require near-100% probability of cost payback as a condition for investing, or may demand a certain probability of BCR ≥ 2 as a way of enforcing a risk premium.
There are additional sources of risk that are not considered in the analysis. In particular, with climate change, there is an increase in risk that conservation fences may be impacted, even destroyed, by natural events such as severe flooding or wildfire [94]. Such events cause major additional costs for fence repair or replacement, possibly affecting the expected economic lifetime of the fence, resulting in major negative impacts on the BCR. Climate change also impacts the ecological functions of wetlands, possibly resulting in a reduction in carbon sequestration achieved by protected wetlands [84,95]. While wetland protection is a nature-based climate solution, the solution itself is directly and indirectly affected by climate change. Risk-based cost–benefit analysis thus needs to be based on up-to-date information about uncertainty of financial and ecological parameters.
The scenarios chosen in this analysis, and assumptions applied, are general in nature; they seek to explore a realm of potential situations that broadly represent the Australian coastal context. The resulting BCR estimates are illustrative in that they provide insights into the relative importance of key assumptions on the hypothetical efficiency of conservation fencing for blue carbon. Anybody who considers undertaking “exclusion fencing”, if and when this becomes an approved method for earning carbon credits, is advised to undertake a cost–benefit analysis tailored to their individual situation. Landholders should explore the full realm of costs and benefits of conservation fencing, account for multiple dimensions of uncertainty, and evaluate the resulting risk, giving consideration to their unique business context and personal preferences.

5. Conclusions

Policy makers require reliable information about the interactions between people and ecological systems so they can implement policies and programs that upscale urgently needed nature-based solutions to climate change [1]. The restoration of coastal wetlands is one such solution and can be achieved through strategic conservation fencing.
This research offers important insights into conservation fencing of coastal wetlands for blue carbon. The research combines literature review, empirical research and cost–benefit analysis to
  • Define a conceptual framework for conservation fencing based on the notions of effectiveness and efficiency;
  • Articulate technical and material requirements of effective exclusion fencing for different ungulates;
  • Provide insights into the options and complexity of decisions associated with the installation of ungulate exclusion fences and associated costs;
  • Compile a systematic and contemporary understanding of material and installation costs of exclusion fencing in different environmental conditions;
  • Provide probabilistic estimates of the BCR of conservation fencing for blue carbon under uncertainty for a range of scenarios that broadly represent the Australian conditions.
Excluding ungulates from coastal wetlands is feasible, provided design, construction and ongoing management of conservation fences ensure their effectiveness as barriers.
Risk-based cost–benefit analysis shows that conservation fencing of coastal wetlands for blue carbon can conceivably become a viable investment option for private landholders who have wetlands with high additional carbon sequestration potential and/or can keep fencing costs low. This finding supports the inclusion of conservation fencing in the portfolio of nature-based climate solutions [96]. However, carbon payments such as those provided for under Australia’s ACCUs scheme offer only a partial solution. In situations where the additional carbon sequestration potential of wetlands is low, income from carbon credits alone is unlikely to justify private investment in coastal wetland restoration. Uncertain future climate change impacts call for further caution. Programs offering up-front grant funding can de-risk investment, while policies and programs that bundle payments for carbon, biodiversity and other ecosystem services can offer higher payments and provide more income certainty for participating landholders, thus strengthening the business case.
Further research is required to provide a nuanced understanding of the human and socio-economic dimensions of conservation fencing for blue carbon. It is currently unknown how landholders may evaluate the potential opportunity to earn income from blue carbon in the context of their business situation, personal values and preferences. Qualitative research can be employed to more fully understand the realm of considerations, complexities and trade-offs perceived by landholders [97]. Additionally, experimental economic surveys [98] can deliver relevant insights into the monetary and non-monetary dimensions associated with participation in such novel environmental programs and critically support policy and incentive design.

Funding

Deakin University contracted River Consulting Pty Ltd. to undertake this research as part of the “Leading the Charge through Nature-Based Solutions” Project. The research was funded by BHP.

Institutional Review Board Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

All data used to support the cost–benefit analysis are reported in this paper.

Acknowledgments

The author is grateful to the fencing experts who participated in the research and generously shared their knowledge. Melissa Wartman conceptualized the project and secured funding for the research. The author greatly appreciates the constructive comments provided by three reviewers.

Conflicts of Interest

Author Romy Greiner is the director of River Consulting Pty Ltd.

Abbreviations

The following abbreviations are used in this manuscript:
AUDAustralian Dollar (Reference Date is October 2024)
ACCUAustralian Carbon Credit Unit, also referred to as a carbon credit
BCRBenefit–cost ratio, representing net present value of income generated by an investment relative to net present value of investment and associated costs
cpiCarbon price index, representing the annual percentage change in the price of a carbon credit
CSRCarbon sequestration rate, representing the amount of greenhouse gases sequestered by a natural ecosystem, measured in t CO2e ha−1 yr−1
MCSMonte Carlo Simulations, a method that uses predefined parameter distributions to randomly assign parameter values in simulation models.

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Figure 1. Nominal future carbon price if carbon price index is defined by ~N(μ = 10% yr−1, σ = μ). Summary statistics are derived from 1000 MCSs for any given year.
Figure 1. Nominal future carbon price if carbon price index is defined by ~N(μ = 10% yr−1, σ = μ). Summary statistics are derived from 1000 MCSs for any given year.
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Figure 2. Estimated BCR of conservation fencing over 25 years for (a) different CSRs of restored wetland and (b) different fencing costs.
Figure 2. Estimated BCR of conservation fencing over 25 years for (a) different CSRs of restored wetland and (b) different fencing costs.
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Figure 3. Probability curves for BCR of conservation fencing 10 years after fence installation, for different CSRs under uncertainty. Assumed fencing cost is AUD 30,000 km−1; 1000 MCSs were modeled.
Figure 3. Probability curves for BCR of conservation fencing 10 years after fence installation, for different CSRs under uncertainty. Assumed fencing cost is AUD 30,000 km−1; 1000 MCSs were modeled.
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Figure 4. Probability curves for BCR of conservation fencing 10 years after fence installation for different fencing cost scenarios under uncertainty. CSR is ~N (μ = 5; σ = 3 t CO2 ha−1 yr−1); 1000 MCSs were modeled.
Figure 4. Probability curves for BCR of conservation fencing 10 years after fence installation for different fencing cost scenarios under uncertainty. CSR is ~N (μ = 5; σ = 3 t CO2 ha−1 yr−1); 1000 MCSs were modeled.
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Figure 5. Probability curves for BCR of low-CSR-wetland conservation fencing 10 years after fence installation, for different fencing cost scenarios under uncertainty; 1000 MCSs were modeled.
Figure 5. Probability curves for BCR of low-CSR-wetland conservation fencing 10 years after fence installation, for different fencing cost scenarios under uncertainty; 1000 MCSs were modeled.
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Table 1. Fencing specifications for different ungulates.
Table 1. Fencing specifications for different ungulates.
Target SpeciesMinimum Fence Height (cm)Graduated MeshFence Skirting
Recommended
(Width in cm)
Electric Top Wire
Recommended if
Feasible
Cattle
(Bos taurus,
Bos indicus)
115NoNoYes
Goats
(Capra aegagrus hircus)
115–125Yes, no gaps at groundYes, 60–110Yes, additional hotwires may be needed to control male goats
Sheep
(Ovis aries)
145YesNoYes
Deer
(Cervcus elaphus,
Dama dama)
185–200YesNoYes
Feral pigs
(Sus scrofa)
90–120Yes, no gaps at groundYes, 60–110No
Water buffalo
(Bubalus bubalis)
120NoNoYes
Compiled from [35,36].
Table 2. Empirical cost estimates of ungulate exclusion fencing obtained from expert interviews.
Table 2. Empirical cost estimates of ungulate exclusion fencing obtained from expert interviews.
Cost
Elements
Baseline Cost EstimatesCost Variations: Considerations and Comments
Material and installation cost17 AUD m−1 to 25 AUD m−1
for fenceline with combination of timber posts and steel pickets

42 AUD m−1
for fenceline requiring concrete posts with galvanized pickets, or for galvanized steel posts and pickets

70 AUD m−1 for stainless steel or all-concrete post fences

200 AUD m−1 for
gates and assemblies

800 AUD m−1 to 1000 AUD m−1 for creek crossings
Costs are approximately 50:50 materials and installation.
Cost estimates are based on use of standard high-tensile galvanized mesh from one of the Australian suppliers.
Cost is, to some extent, dependent on length of fence: Short fences typically cost much more per meter as mobilization cost is the same irrespective of the length of the fence. Scale-induced cost savings cease upwards of approximately 1 km length, as long fences typically involve longer on-site transport distances.
There is virtually no difference in the installation cost between 5-strand barb wire and mesh netting; while material for barb wire fence is comparatively less, there is more labor required for installation.
An apron adds approximately AUD 5 m−1 to the material cost.
Raising fence height to exclude deer requires more wire, larger posts and bigger strainer assemblies; this approximately doubles the cost of the fence.
Each gate, waterway crossing and square (or sharp) corner requires two strainer assemblies (i.e., one on either side). The cost of a steel strainer assembly is approximately AUD 600. A mild corner only requires a stronger corner post, plus a support post.
Floodway installations are required wherever fast-flowing water occurs. AUD 10,000 buys a 12 m creek crossing with fixed pipe, chains and hanging panels.
Installation of a fence in an ecologically sensitive or very wet site may mean that all posts need to be driven by hand, resulting in higher labor costs.
Fence installations in remote locations incur higher labor cost due to travel time and travel-related expenses.
A machinery delivery charge is applicable to bring machinery such as excavators, tractors, attachments and tools on-site. The standard float cost for an excavator is AUD 4000. Machinery and tools also incur daily hire costs.
Material costs have increased approximately 70% over the past 3 years since COVID-19. Contractors have not yet passed on the full cost increase to customers.
Ongoing freight cost increases and other inflationary pressures are anticipated in future years, adding around 10% per year to costs going forward.
Fenceline preparationAUD 2.50 to AUD 5.00 m−1This baseline cost is for minor leveling and clearing.
Most exclusion fences require a 6 m wide clearing for access for installation of apron mesh netting and ongoing fence maintenance.
An excavator plus operator costs approximately 1600–2400 AUD/day, depending on the size of the machine, and clears 1 km per day in ideal conditions.
If country is heavily timbered, clearing may require a bulldozer, which increases per-meter cost.
Maintenance costDepreciate fence over 10 yearsThe rule of thumb is to depreciate an exclusion fence in coastal or saline conditions over 10 years.
Timber, treated or untreated, will generally only last 10 years.
Maintenance costs can be expected to be low in the first 10 years, s.t. favorable conditions, as only regular inspections for potential breaches are required. As a guide, annual maintenance costs are 2% of installation costs.
High maintenance costs—equivalent to depreciation costs and possibly higher—are likely to occur once the fence starts to deteriorate beyond 10 years.
The economic lifespan of a fence is determined by material use. Fences made of stainless-steel posts and mesh netting will last much longer, as will fences with all-concrete posts, which withstand fire, termites and also floods.
In heavily timbered conditions, maintenance includes the suppression of tree regrowth with long-lasting herbicides to ensure continued access to a fenceline and reduce the risk of damage from fallen trees.
All dollar values are current as of October 2024.
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Greiner, R. Conservation Fencing for Coastal Wetland Restoration: Technical Requirements and Financial Viability as a Nature-Based Climate Solution. Sustainability 2025, 17, 7295. https://doi.org/10.3390/su17167295

AMA Style

Greiner R. Conservation Fencing for Coastal Wetland Restoration: Technical Requirements and Financial Viability as a Nature-Based Climate Solution. Sustainability. 2025; 17(16):7295. https://doi.org/10.3390/su17167295

Chicago/Turabian Style

Greiner, Romy. 2025. "Conservation Fencing for Coastal Wetland Restoration: Technical Requirements and Financial Viability as a Nature-Based Climate Solution" Sustainability 17, no. 16: 7295. https://doi.org/10.3390/su17167295

APA Style

Greiner, R. (2025). Conservation Fencing for Coastal Wetland Restoration: Technical Requirements and Financial Viability as a Nature-Based Climate Solution. Sustainability, 17(16), 7295. https://doi.org/10.3390/su17167295

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