Resource Database

Investigating the links between eco-cultural clam garden restoration, sediment structure, and bivalve productivity.

On the Pacific coast of North America, Indigenous communities have enhanced clam populations through time by building rock-walled terraces in soft-sediment intertidal habitats and actively tending these “clam gardens”. Today, clam biomass and density are decreasing regionally due to degraded ocean conditions, yet, clam gardens have double to quadruple the biomass of clams compared to unwalled beaches. A Coast Salish led clam garden restoration experiment aims to better understand the drivers behind physical mechanisms that increase clam productivity. As one component of the study, we are evaluating how active beach tending and rock wall reconstruction affect sediment characteristics using a before-after, control-impact design. Following the first five years of restoration, we hypothesize grain sizes will shift towards coarser size classes as the rebuilt wall traps gravel on its landward side and beach tiling increases the transport of silts offsite. Within the same time frame, we hypothesize beach tending will increase the carbonate content of sediments via an increase in crushed shell. With existing biological data, we will analyze the relative importance of shifts in habitat structure on bivalve biomass and density. Initial findings show variation in carbonate levels among tidal heights and sites. Clam gardens have higher carbonate levels at the low intertidal compared to non-walled beaches. Building on previous work that has examined increases to clam production on untended clam gardens, this large-scale study will help explain the effects of human management on habitat conditions and the mechanisms driving variation in clam productivity

Let your mussels do the talking: Using individual and clump morphology as indicators for restored mussel survival

Active restoration of shellfish reefs is becoming an increasingly popular option to recover habitat and ecosystem function to degraded coastal areas. In New Zealand, the loss of over 1500 km2 of subtidal green-lipped mussel (Perna canaliculus) reefs has incentivized efforts to recover this critical habitat to its historic range. Current restoration efforts rely on spreading adult (70-100 mm shell length (SL)) mussels across soft-sediment seafloor, which is effective albeit inefficient. There is growing interest in using subadult mussels (30-50 mm SL) to make the restoration process more efficient, however, more information is needed to develop large-scale methods for overcoming predation and hydrodynamic dislodgment that currently limit subadult mussel survival. This presentation will discuss how small variations in individual mussel and mussel clump morphologies correlate to large differences in their survival. In this study predator-resistant characteristics (attachment thread morphology and shell strength), mussel clump morphology, and survival following experimental deployments to a restoration site were compared in mussels from five populations. High survival was represented by mussels that formed compact, contiguous clumps (92.3 – 99.0%), possessed thicker and more numerous attachment threads (92.3 %), and/or greater shell strength (95.5 – 99.0 %). These results suggest that careful selection of subadult mussels that exhibit these characteristics improves resistance to predation and hydrodynamic stress, and thus restoration success. These data provide a framework for more developing more nuanced approaches to mussel reef restoration that use mussel biology to inform restoration strategies in New Zealand and for other species around the world.

Medium-term monitoring reveals effects of El Niño Southern Oscillation cycles on oyster reef restoration

Human activities and regional-scale climate variability are driving changes in the ecology of coastal and marine ecosystems worldwide. Ecological restoration has emerged as a best management practice to combat habitat degradation and restore lost ecological functions. However, relatively short project monitoring timeframes have limited our understanding of the effects of interannually climate cycles on water quality and restoration dynamics. We collected measurements on a 23 ha oyster reef constructed in the Gulf of Mexico for five years after reef construction to determine significant correlations between regional climate signals and local environmental and faunal dynamics. The potential role of climate variability on local salinity patterns (from changes in precipitation and evaporation) and faunal dynamics was investigated using the Oceanic Niño Index (ONI), a measure of El Niño Southern Oscillation (ENSO). ONI was correlated with salinity that occurred two to five months later. Positive ONI (El Niño) periods were characterized by reductions in salinity, increases in oyster recruitment and density, and reductions in resident motile fauna density and species richness. Negative ONI (La Niña) periods had higher and less variable salinities, and higher areal coverage of restoration substrates by large oysters. ENSO-driven salinity reductions in the second year after reef construction coincided with a shift in resident motile faunal community composition that was maintained despite  a second strong salinity reduction in year 5. In order to support the use of habitat restoration as a conservation and management tool, results indicate it is important to expand the temporal resolution of monitoring timeframes to at least five years so that resource managers and restoration practitioners can better understand how both short-term environmental variability and longer-term climate cycles can affect the outcomes of restoration actions.

Testing habitat suitability for mussel restoration after large scale decline

Natural green-lipped mussel (Perna canaliculus) populations are scarcely found in places where they once flourished throughout New Zealand, although they provide vital ecosystem services for our oceans. While restoration efforts have been attempted in the North Island, there has yet to be any wide scale restoration effort on the South Island, including the Marlborough Sounds. The Marlborough Sounds are a unique environment located in the top of the South Island, but with the loss of the native natural bivalves, the once-flourishing benthic community has experienced a shift. This shift may have impacted the environment such that it is no longer suitable to support mussel populations. With this in mind an effort to test habitat suitability at five locations that previously supported mussels began in January 2020. We transplanted four tonnes of local brood stock into these five locations in the Marlborough Sounds. At each location we performed preliminary surveys to characterize site differences including sediment analyses and benthic community characterization. The mussels were placed in three, 2.25 m2 plots at each location. Mussel survival, density, growth, and condition were recorded four times over a year. Mussel survival was high across all five sites after one year and each of these 15 plots of mussels will continue to be monitored for an additional year. As well as its relevance locally, the study more broadly provides insight for assessing suitable habitats to maximize efficiency and success of future restoration efforts.

Blue carbon in national greenhouse gas inventories – overcoming challenges in tropical countries

Coastal wetlands, including mangroves, tidal marshes and seagrasses, sequester significant amounts of carbon dioxide (blue carbon), while also providing valuable ecosystem services. Although their global area is smaller than terrestrial forests, their per unit area carbon sequestration is greater, because of the accumulation of soil carbon, contributing to the climate change mitigation potential of  coastal wetland restoration.

The value of sustainably managing coastal wetlands is recognized by the United Nations Framework Convention on Climate Change. Under the Paris Agreement, participating countries are required to report their greenhouse gas (GHG) emissions and removals using IPCC guidelines for national GHG inventories. Despite the availability of GHG guidance to include change in coastal wetlands, few countries have applied the guidance. Review of national climate change actions found that mangrove holding countries often consider coastal wetlands in their adaptation plans, but rarely in their estimation of GHG emissions/removals or mitigation. Some countries, such as Indonesia, have included mangroves for results-based payments under Reducing Emissions from Deforestation and Forest Degradation (REDD+). Indonesia is including managed coastal wetlands in national GHG inventory and has recently announced ambitious targets to restore 600,000 ha of mangroves by 2024.

We explored the opportunities and challenges for incorporating coastal wetlands into national GHG inventories in Fiji and Indonesia, and developed advice for tropical countries on how to overcome these challenges considering previous IPCC guidance. By incorporating coastal wetlands within national GHG inventories, countries can recognize the valuable contribution they provide to climate change mitigation, helping to meet GHG emission reduction targets.

Long-term assessment of ecological degradation of a large coastal wetland system in Los Angeles, CA

Coastal wetlands are unique transitional areas containing diverse organisms adapted to living in the dynamic interface between fresh and salt water; however, the proximity of these systems to coastal development increases impacts. In southern California, anthropogenic stressors have resulted in a 75 98% loss of estuarine habitat. Remaining habitats suffer from various levels of degradation, as in the case of the 577-acre Ballona Wetlands Ecological Reserve (Reserve). More than a century of anthropogenic impacts has altered distribution, extent, and nativity of vegetation communities. However, the Reserve is the largest opportunity for coastal wetland restoration in the Los Angeles region. This project’s objective is to increase knowledge of the long-term functioning of this degraded estuarine wetland to inform adaptive management and restoration.

Data evaluated for this study include long-term assessments of jurisdictional wetland extent (and loss), California Rapid Assessment Method (CRAM) scores (standardized condition assessment), and species-level vegetation cover surveys and mapping. Mapping vegetation associations over time provides data on species invasions and the nativity of areas.

Overall, altered hydrology and topography have reduced salt marsh habitat availability and significantly modified the ecological community, including reduced wetland extent. Site-wide trends demonstrate that many areas suffer from high degrees of invasion by habitat-altering plants such as Carpobrotus edulis. CRAM surveys found that average scores declined over the study period. Wetland delineation surveys found that approximately a quarter of the site is considered delineated wetland, and an even smaller portion is exposed to tidal influence. These data will be used in restoration planning

Bois d’Arc Lake and Watershed-Scale Ecological Restoration: a Historic Reservoir and a Texas Sized Mitigation Project

The North Texas Municipal Water District (NTMWD) is currently constructing a surface water reservoir in Fannin County, Texas to supply a growing regional population; the first reservoir in Texas in approximately 30 years. Environmental impacts from the resulting Bois d’Arc Lake are being mitigated by restoring, enhancing and preserving over 14,000 acres of wetland and upland habitats and 70 miles of ephemeral, intermittent and perennial streams within the same watershed. Much of this restoration takes place on property formerly used for agriculture and livestock production for over 100 years.

The scale of this mitigation project is significant: approximately 8,500 acres of forested, emergent and scrub shrub wetland; 2,600 acres of upland forest; and 3,200 acres of native grassland restoration and enhancement; and over 392,000 linear feet of stream restoration, enhancement and establishment. Restoration and perpetual protection of these habitats will decrease erosion, sedimentation, and nutrient loads in a significant portion of the Bois d’Arc Creek watershed that drains into the Red River between Texas and Oklahoma.

This presentation will provide background on development of the Bois d’Arc Lake Mitigation Project as well as its current status over one year into construction. We will discuss the variety of habitats on-site, restoration techniques employed (including innovative use of local native materials), and lessons learned to date on ecological restoration at this scale. We will also discuss how NTMWD used a novel full-service provider contracting mechanism to reduce project cost and transfer longterm risk, providing a model for future large-scale restoration projects.

Considerations for the Long-term Management of the Invasive form of Common Reed (Phragmites australis)

The nonnative form of common reed (Phragmites australis) is well known as an invasive species of coastal and inland marshes and widely accepted as having negative effects on biodiversity and wetland functions in comparison to undisturbed wetlands. In the U.S., both large and small scale projects have been implemented with the goal of eradication or significant reduction of common reed stands followed by the restoration of native plant communities. These efforts have been ongoing for over 25 years with varying levels of success which have led to a narrowing in the treatment methods to a core group of effective approaches. The types of projects that incorporate common reed management can range from large scale programs with relatively secure funding for long-term management, to relatively short duration (3 – 5 years) wetland mitigation projects with no long-term management requirements.

Through project experience and field observation, common reed reintroduction into previously restored sites that have not undergone significant hydrologic change remains a threat to the benefits achieved. An element of these types of projects that deserves further exploration is how biodiversity and functional gains, once achieved, can be maintained into the future, and what type of political, financial and cooperative mechanisms are required to support long-term monitoring and maintenance actions. This presentation will explore current programs with different approaches to provide long-term management of common reed, including the Great Lakes Phragmites Collaborative, a Wetland Mitigation Bank, and a State funded program for Wildlife Management Areas that could serve as potential models for managers.

Methane emissions and dissolved organic carbon concentration of a constructed fen over the first seven years of ecosystem development

Wetlands comprise a large portion of the pre-disturbance landscape in the Athabasca Oil Sands Region (AOSR) and have become a focus of reclamation in recent years. An important aspect of wetland reclamation is understanding the biogeochemical functioning and impact on carbon exchange, including methane (CH4) and dissolved organic carbon (DOC). Here we report on the CH4 emissions and DOC concentration and chemistry over the first seven years of ecosystem development. Methane emissions were measured using manual static chambers between 2013 and 2019, alongside environmental variables such as water table depth, soil temperature and vegetation cover. DOC concentration and specific ultraviolet absorbance (SUVA) were measured monthly at 50 cm depth in a series of piezometers in three transects across the fen. Methane emissions remained low throughout the majority of the measurement period; however, in later years, a small increase became apparent. Increasing salinity levels and high levels of sulphate are likely the cause of the low CH4 emissions found, despite a consistently high-water table and the dominance of vegetation with aerenchymous tissue such as Carex aquatilis and Typha latifolia in later years. DOC concentration increased consistently over time while SUVA decreased. This indicates a decline in the aromaticity of DOC, suggesting increasing plant contribution. Meanwhile, DOC concentration in the fen was also positively corrected to sodium concentration. This assessment of the drivers on CH4 emissions and DOC concentration during early development at this constructed fen indicate that local chemical conditions are important drivers of carbon biogeochemistry in an oil sands reclamation context.

Program for Restoring and Creating Wetlands and Bodies of Water

Québec’s lower St. Lawrence River wetlands have experienced significant losses in area since the onset of European began. Bodies of water have also been transformed over the course of recent decades in order to improve the drainage and productivity of agricultural lands.

However, wetlands and bodies of water fulfill a variety of ecological functions. Today, these ecosystems are insufficient in number in several lower St. Lawrence River basins to deal with climate change. Creating and restoring wetlands and bodies of water is now the preferred approach used to counterbalance the inevitable losses and disturbances experienced by these environments.

In order to reach the no net loss objective for wetlands and bodies of water, the Act respecting the conservation of wetlands and bodies of water was adopted in June 2017, and an initial province-wide, three-year Program for Restoring and Creating Wetlands and Bodies of Water, was launched in June 2019. The aim of the program is to redistribute to Regional County Municipalities, the amounts paid into a fund to compensate for the inevitable loss of wetlands and bodies of water within their boundaries. The initial program has a total budget of $30 million (divided into two components) that will enable it to fund projects for restoring and creating wetlands and bodies of water. The first call for projects was launched in the winter of 2020. Part 1 covers prefeasibility studies, while Part 2 funds restoration and creation projects. The best projects will be selected by the Ministère and a committee of independent experts.

Thinking ahead for road rehabilitation in wetlands

Constructing safe and durable access roads within peat harvest sites is crucial for both logistical reasons and fire risk management. These access roads may, however, impede water flows and leave undesirable topographical attributes to a restored peat harvest site. Premier Tech Horticulture has developed an operational framework into which road restoration planning is integrated from construction to decommissioning. Roads are constructed using non-merchantable timber from the newly developed site to create a buoyant layer of corduroy onto which a layer of clay and gravel is added. The corduroy layer must be thick enough to support heavy machinery and requires the right density to alleviate the need for a geotextile membrane to hold the layer of clay and gravel. This proven road design allows a passive flow of water on both sides without requiring culverts, and the absence of geotextile greatly reduces rehabilitation costs. Upon rehabilitation, the whole road constituents are inverted so that the mineral layer and the corduroy are buried under freshly exposed peat. Road construction and maintenance techniques will be presented, as well as a road rehabilitation pilot project initiated in 2018 in Athabasca, (AB, Canada) where a Peat Inversion Technique (PIT) was adapted to suit a depleted peat harvest site.

A participatory process for ecological restoration of mangroves in Pantanos de Centla Biosphere Reserve (Tabasco, Mexico)

Ecosystem restoration is an essential activity to recover degraded areas, improve human well-being, and preserve biological diversity, particularly in countries with major socio-environmental challenges like Mexico. As a strategy to mitigate climate change effects, the objective of this project was to restore 50 hectares of mangroves inside a natural protected area, Pantanos de Centla Biosphere Reserve (PCBR).

A participatory restoration process was developed with two local communities (El Palmar and Tembladeras) that inhabit PCBR. This process involved three main phases: planning, implementation, and monitoring. During planning, the communities’ restoration interests and needs were identified, a socio-ecological diagnosis was made, and actions to be developed were defined among all actors involved. In the implementation phase, 20,5 ha in El Palmar was reforested with 17,000 Rhizophora mangle propagules to increase vegetation coverage in natural channels, and hydrological rehabilitation was performed in 4900 meters of different segments of natural channels in Tembladeras. Simultaneously, training workshops were conducted with both communities, focusing on mangrove ecosystem services, the methodological sequence of restoration processes, and some monitoring techniques.

During the monitoring phase, communities supported evaluation activities that produced results indicating that both actions were generating the expected benefits for them. Survival of mangrove propagules was high (74%) and hydrological rehabilitation effectively recovered the functionality of natural channels for fishing activity. Workshops reinforced the community involvement and strengthened local capacities for conserving and managing mangroves. The project has demonstrated that social participation is fundamental to ensure continuity in restoration processes and to increase their probability of success.

Bringing nature back into our lives in cities of the desert: A case study from the Canary Islands

Arrecife is a city with more than sixty thousand inhabitants located in the desert of the Canaries, in the southeast of the island of Lanzarote. A high percent of the ecosystem has disappeared in the area because of the expansion of urbanized plots and infrastructures. ‘Arrecife Natura’ is an environmental charity founded in 2019 and dedicated to restoring the desert ecosystem in the city and urban border. With a zero euro budget, recycled materials, volunteers from the local community, the social media, and seeds from urban wild populations, we are rewilding sites around the city using native plants propagated in neighbors’ patios, terraces and roofs. We are also working with the city council to alter the policy of removing wild herbaceous plants from urban spaces. Using native species has the benefit that once established, we can step back and leave the area to nature with minimal intervention such as irrigation (biggest challenge in the desert). This approach to restoration using native species creates green spaces that require little to no long-term intervention, and benefit the wellbeing of local communities. Together, we are planting the seeds of a greener future for the city of Arrecife.

Reconnecting with land: a private restoration project in Chilean Patagonia

The main theme of the Conference is the “New Trajectory”, however the ecological restoration cannot be effective without prior restoration of our relation to the land. With the multiplication of private protected areas globally, landowner practitioners, who restore nature areas they own, form nowadays an important group of restoration practitioners.

Their land is generally smaller than state- or privately-protected (by non-State legal persons) areas, but constitutes an enrichment of the diversity of restoration paradigms, perspectives and experiences, often ignored by the institutionalized approach to restoration focusing on government agencies and academic research. The “owner practitioners” face the same challenges worldwide: the need to be a polymath, relying on, and sharing, own aspirations and experience. Often the rehabilitation or restoration has no commercial or immediate “service” value, but is aimed at rebuilding ecosystems. Because they lack the security of a legal entity, access to funding or other support is limited. Long-term legal and other protection is essential but difficult to secure.

The above and other issues are reflected in a case study based on 15 years experience with a private project in Chilean Patagonia. The area is adjacent to the San Rafael National Park, was severely degraded in the last century, needs restoration (soil, native forest, wetlands) and serves as a buffer for the park, wildlife corridor and habitat for endangered species. The case study relates experience and successes useful for other owner practitioners by outlining approaches taken to address the environmental degradation, legal issues encountered, and challenges faced.

Social participation in forest restoration projects: insights from a national assessment in Mexico

Ecosystem and landscape restoration are increasingly incentivized worldwide, and many countries are demonstrating political will for achieving ambitious restoration objectives. Despite the involvement of all society sectors in restoration activities, projects frequently fall short of addressing the social dimension in their planning, implementation and monitoring phases. In Mexico, 56.3%; of the population lives in poverty, 53.4% of which is indigenous people living in common-pool systems. Therefore, these communities are one of the most important decision-making groups in terms of forest restoration. However, a rigorous survey about the social dimension of forest restoration has never been carried out. In this study we evaluate the degree to which restoration projects in Mexico address social aspects. We analyzed 75 ecological restoration projects. We found that 47% of projects were established in common-pool systems (many in State Protected Natural Areas) and 98.5% were funded by the government. Despite the participation of community members in 86% of the projects, in 78% of them, this participation occurred only during the execution of the restoration actions, leaving the social participation unaddressed during the planning, and monitoring phases. Although, the third most important goal of projects was generating employment, this labor force was temporary and has served only to alleviate social tensions for a short time. The diffusion of restoration projects is still scarce. Thus, this type of social participation cannot make restoration projects fairer and more inclusive, nor do they have the capacity to increase their sustainability and permanence in the future.

Wastelands transformation: enhancing adaptive capacity of social ecological systems, under the global change

Adaptive capacity, in the face of environmental change, is crucial for building resilience of coupled social ecological systems across spatial, temporal, and institutional scales. The wastelands “i.e., abandoned lands” redevelopment could help to increase the adaptive capacity (AC) of societies and ecosystems in the face of current and future change. Nonetheless, most regeneration approaches are based on cost and economic benefits sensed estimates of wastelands value after reclamation, especially in France. Our aim is to frame the transformation of wastelands as a strategy to improve social and ecological AC, at local level, that is to say, a way of organizing the action with a view to achieve the resilience and to help human and natural systems to better adapt to environmental global change. We argue the necessity for such a transformation strategy and provide examples from literature with regard to the concept of AC and the potential contribution from applying ecological restoration insights in the management of wastelands.

Wastelands transformation could enhance different determinants of AC: 1) at ecological level, mainly: diversity and distribution of species, ecological connectivity, habitat heterogeneity, life history traits, like dispersal capacity, preservation of abiotic parameters; and 2) at the social level, as like as: improving the resources and existing assets; flexibility and alternative development, more participatory and deliberative governance in the planning of regeneration projects; learning and willingness to take adaptive actions. Social and ecological adaptive capacity complement each other, thus, both are crucial for the resilience of the social ecological system.

Advancing the Practice of Soil Bioengineering in Alberta – the Bow River Bioengineering Demonstration and Education Project

The Bow River Bioengineering Demonstration and Education Project (BDEP) is an award winning, next generation riverbank erosion protection project. Borne in response to the 2013 flood, it was the largest initiative under the Alberta Environment and Parks department Southern Alberta Fisheries Habitat Enhancement and Sustainability program. The project includes three key elements: design and construction of a bioengineering demonstration site on the Bow River in Calgary, a monitoring program to assess the effectiveness of the constructed works, and an education program to educate professionals and the public about the advantages of using bioengineering techniques.

Project design and construction were completed from 2016 to 2019. Fourteen different bioengineering techniques were constructed along 720 m of riverbank. Seven commonly used techniques were constructed to showcase how they can be achieved successfully. Seven innovative bioengineering techniques were piloted to expand the engineering design toolbox in Calgary. Over 100 trees, 2300 potted shrubs, and 30,000 live cuttings were planted at the site. Over 2000 tonnes of concrete rubble, wood debris, and steel were removed from the riverbank.

Post-construction monitoring of fish, wildlife, riparian health, and structure integrity will occur at the BDEP over a 10-year period from 2019 to 2029. Results for 2019 and 2020 monitoring show that planted vegetation survival is 76%, both fish and wildlife are using the wildlife passage corridor and constructed fish habitat, and riparian health has improved.

Ongoing education initiatives include interpretive site signage, site tours, technical presentations, and a City of Calgary website that openly shares project technical documentation

Effect of Reclamation Practices on Soil Water Quality

Proper reclamation of surface mined lands is vital for adequate restoration of ecosystem services. To that end, a 5-step reclamation process – The Forestry Reclamation Approach (FRA) – was developed for reforestation of surface mined areas in the Appalachian Region, USA, in the early 2000’s. FRA practices are easy to implement and result in significant improvement to plant establishment and growth. While these effects have been extensively studied, the practices effect on soil biogeochemical processes and soil water quality are not well documented.

We present results from a 3-year monitoring study of FRA sites (WV, USA) instrumented with soil water sampling devices 12 years after reclamation. The study site established in 2005 and include two 2.8-ha 1.5 m deep plots constructed using only Brown (oxidized) or Gray (reduced) sandstone overburden material. Each plot was split into compacted (overpass by D-10 caterpillar dozer) and non-compacted material placement subplots. Each plot, along with adjacent undisturbed forest, were instrumented with three shallow observation wells (1-m deep) each, randomly placed within the plot area. Water samples were collected weekly, filtered on-site through 0.45µm filter, split into three subsamples that were capped with minimal headspace and delivered on ice to the lab where they were kept refrigerated prior to next-day analysis for ionic composition, total alkalinity, and dissolved organic carbon. A field acidified sub-sample was stored for metal analysis. YSI Pro Plus multiparameter meter was used for in situ measurement of dissolved oxygen, pH, temperature, total dissolved solids (TDS), and redox potential in the wells prior to water sample collection.

An increase in TDS was found when redox potential decreased (which itself was inversely related to pH). This increase in TDS under anoxic conditions was surprising and improved our understanding of the role of redox-promoted dissolution in these, otherwise, upland, supposedly well-drained soils. Wide temporal fluctuation in all measured parameters was recorded and are attributed to the poor ability of the newly constructed soil to properly buffer changes in moisture, pH, and redoxpotential. The results are discussed in the context of soil development, resiliency, and vulnerability amid expected extreme weather events.

Finding Onsite Restoration Solutions for Hydrologic Issues Caused by Off-site Development: Two Case Studies of Hardwood Swamps in Ontario, Canada

Two case studies are explored where off-site development altered wetland hydroperiods and threatened the persistence of deciduous swamp communities (Mixedwood Plains ecozone). The project objectives were to: compare existing hydroperiod conditions against the suitable hydroperiod for the swamp type (using feature-based water balance analysis), identify mitigation measure(s) to bring the hydroperiod closer to suitable conditions, and obtain buy-in from agencies and stakeholders.

In the first case study, the outlet of an off-site storm water management pond was constructed near the boundary of a wetland complex that contains provincially rare Bur Oak swamp. This increased surface water contributions to the wetland by 158% and exceeded the flood tolerance of Bur Oak. The best solution given the limited space available (only 30m between the wetland and proposed on-site development) was to divert the first 7.5mm storm event into a diversion swale while allowing the >7.5mm storm event to enter the wetland complex.

In the second case study, preliminary studies suggested upstream residential development caused a substantial increase in surface water contributions to a Swamp Maple-Hardwood swamp. The site-level water balance raised concerns that the swamp may be converting to an open marsh community. The case became more complicated when it was discovered the swamp was partially groundwater dependent, was not riparian, and behaved as a cascading system. The best mitigation measure was to direct all surface water flows from on-site development away from the feature.

For both cases, the future vegetation communities are discussed along with preliminary observations of current swamp health.

Long-term Reclamation Outcomes after using Varying Depths of Subsoil to Cap Sodic Overburden

Capping sodic overburden with subsoil or other non-sodic material is a common practice in mining to create a suitable growth medium for vegetation. Several studies were conducted in the 1970s, 80s and 90s to determine an optimal placement depth of subsoil to balance vegetation growth with costs associated with subsoil handling. These studies concluded that depths of 50 to 100 cm would provide a suitable rooting depth for vegetation and buffer against upward migration of sodium from the overburden. These conclusions were generally based on results obtained 5 to 10 years after subsoil was placed over sodic overburden. As development of soil processes and movement of elements in soil can take decades to centuries, the conclusions can be considered preliminary. As some of these previous study locations are still intact, it is possible to remeasure these locations to obtain longer term results and verify earlier conclusions. One such study was set up on agricultural land at Highvale Coal Mine, Alberta, Canada in 1982. It was monitored between 1982 and 1987, in 2001 and most recently in 2016 (34 years after subsoil capping). Migration of sodium into the subsoil cap was minimal between 1987 and 2016 and a capping depth of 55 cm plus 15 cm of topsoil produced a similar crop yield to capping depths thicker than 300 cm. Long-term results support previous conclusions that 50 to 100 cm of capping over sodic overburden can sustain crop productivity.

Managing flood flow connectivity to landscapes to build buffering capacity to disturbances: an ecohydrologic modeling framework for drylands

Increased flooding, droughts, and sediment transport are watershed-scale problems negatively impacting agriculture and ecosystems in drylands worldwide. Vegetation loss in upland watersheds is leading to scouring floods, which in turn decreases infiltration, soil moisture levels, and downstream groundwater recharge. Management to confront these intractable problems has been hindered by a lack of accessible decision support tools for both land and water managers that synthesize the watershed processes that buffer against dryland disturbances. Flood flow connectivities across the landscape create buffer zones through replenishing soil moisture and reducing flood energy, which in turn support multiple functions. This study developed a decision support tool, the Flood Flow Connectivity to the Landscape (FlowCon) framework that quantifies the most efficient management efforts to increase the key watershed buffering functions of increasing infiltration and reducing flow energy. FlowCon links three spatially explicit, process-based, and predictive models to answer two critical management questions: what key processes acting in what optimal areas are drivers of infiltration dynamics and what roles do peak flows of differing scales of energy play. We calibrated the models with measured runoff and corresponding rainfall events for a six-year period. The synthesized ecohydrologic indicators provided critical and statistically significant calibrations. Implementation of prioritized management is estimated to reduce peak flow by half, with focused interventions infiltrating three times the flow volume per area than the floodplain average. FlowCon provides an efficient assessment framework that integrates watershed process understanding in an accessible decision support tool to achieve tangible improvements in dryland watershed management.

Natural colonization and active inoculation of disturbed soils with biological soil crusts in northern Canada

Examining natural colonization of biological soil crusts (BSCs) on arctic, alpine and boreal soils of northern Canada, following glacial retreat and anthropogenic disturbances can inform active restoration. Biological soil crusts are early soil surface communities composed of bryophytes, lichens, bacteria, cyanobacteria and fungi. Their ubiquitous distribution, ability to survive harsh conditions and influence on soil and plant community development make them important for restoration. Longterm changes (~70 years) in BSC community composition and function across an alpine glacial foreland were evident based on metagenomics sequencing of the BSC community and measures of in-situ and optimal carbon and nitrogen fixation. Over the short-term (<30 years) BSC macrophyla (bryophytes and lichens) richness appeared to remain relatively constant in both a northern boreal and a low-arctic tundra landscape disturbed by mining activities, however, changes in species composition were evident. Fungal communities demonstrated the strongest changes in richness and composition in these recently disturbed landscapes. These shifts in the BSC community were linked with changes in nitrogen fixation, photosynthesis and organic carbon. Active inoculation of BSCs in growth chamber and field studies further identified changes in community development, composition and function driven by moisture and fertilization. Moisture promotes increased community development, especially of bryophytes, accompanied by higher normalized difference vegetation index (NDVI) values and higher rates of photosynthesis. Fertilization also promotes increased BSC cover and NDVI and increased organic carbon in soils directly underlying BSCs. Providing conditions that promote key BSC species and functions, identified through observing natural colonization, is essential for effective restoration.

Salvage and Restoration of Biological Soil Crust on an Urban Superfund Site, Midvale, UT (USA)

Biological soil crust became an unexpected focus of restoration at a Superfund site in Midvale (Salt Lake County), UT (14.4” annual precipitation). Jordan Bluff was a steel mill tailings pile active from 1906 to 1971, remediated in the 1990s, and removed from the Superfund National Priorities List in 2004. Although it had already been designated for native habitat restoration as part of a multi-use urban development, the presence of volunteer Syntrichia sp. and other soil crust assemblages was not known until an ecological site assessment, prompted by pursuit of LEED certification. Thanks to a sustainability-minded client the soil crust became the center of attention for education, restoration, and the construction schedule. A crew was mobilized to salvage and store the crust until its redistribution post-planting (still pending). Biological soil crust communities are essential to soil stabilization, water infiltration, and fertility in arid ecosystems. This presentation will describe the steps taken to date at Jordan Bluff, review the state of knowledge of soil crust restoration methods, and discuss the relevance of crust restoration in the context of climate change and desertification.

Assessing the success of various restoration treatments in terms of vegetation recovery and cost effectiveness

The successful restoration of critically endangered habitat types at a low cost is of vital importance as we enter the UN Decade on Ecosystem Restoration. Here we test how successful and cost effective six combinations of restoration treatments were over a period of two years in the Cape Floristic Region of South Africa. Treatments used were: Burn, Burn-sow, Burn-sow-plant, Remove-grass-sow-plant, Soil plant and Soil-mulch-sow-plant. The combination of fire, seed and planting lead to plant diversity most similar to the control plots. The treatment that involved the use of topsoil transfer in combination with planting was the second most successful restoration treatment. Treatments that involved the manual removal of alien graminoids proved to be the least successful. Sowing contributed minimally to restoration where it was used with fire alone but was more successful when used with planting or the application of mulch. The manual removal of alien graminoids proved to be the most expensive treatment, whilst the treatment that only involved a controlled burn was the cheapest. We conclude that the combination of fire, seed and planting was the most successful treatment at a reasonable cost, while the transfer of topsoil from an intact site combined with planting was also successful in transferring an otherwise lost habitat.

Development of Soft Tailings Capping Technology to Create Stable and Sustainable Boreal Landscapes

The production of synthetic crude oil generates large volumes of fluid tailings comprised of process water, sand, silt and clay along with residual bitumen, diluent and other chemical constituents remaining from the extraction process. Given the nature and scale of tailings generated by oil sands mine operations, returning soft tailings deposits back to an ecosystem of equivalent  land capability is a complex challenge faced by all operators in the Athabasca oil sands region. This meso-scale greenhouse study uses 55 gallon columns to evaluate the growth and establishment of various boreal plants on treated fluid tailings under various capping treatments over 3 years; results from the first growing season will be discussed along with the baseline characterization of the tailings and materials used.

Capping depth treatments were applied to centrifuge, co-mix and thickened tailings followed by planting boreal upland and wetland communities. After one growing season, survival was high for most species among tailings types. The vegetative cover of forbs and graminoid species, height incremental growth of woody species and root development were greater in treatments with 30 cm of peat-mineral mix reclamation cap. Of the species planted, Scirpus microcarpus and Triglochin maritima were least impacted by tailings compared to Betula pumila. The constituents that may impact plant growth include Na, B and naphthenic acids, monitoring the change of those constituents in tailings, expressed water and plant tissue will be highlighted in this presentation.

Fertilization of substrate surrounding transplanted low-Arctic tundra sods significantly increases belowground biomass development

Low Arctic ecosystems in Canada present significant challenges for ecological restoration, including remote locations, harsh climates, short-growing seasons, and a lack of readily available native propagules. There is a need for low technology based approaches that employ local and on-site materials. Previous research has identified transplantation of “sods” (i.e., blocks of native vegetation and soil) as a simple, cost-effective, and efficient method for revegetation of disturbed sites. This study examined the responses of transplanted sods (approximately 0.13 m2 by 0.1 m deep) to nitrogen and phosphorus fertilization in a growth chamber experiment using sods harvested from undisturbed dry-heath tundra near Rankin Inlet, Canada. Aboveground plant community composition and normalized difference vegetative index (NDVI) images were assessed 140 days following fertilization to examine aboveground responses and vegetative health. Belowground biomass exiting the sod was determined and species identified through next-generation sequencing. Preliminary results indicate limited change within the aboveground community of the sods, however, fertilization of the surrounding substrate significantly increased root expansion from the sods, and resulted in significantly higher NDVI values, moss cover, and biological soil crust development on the substrate. Our study indicates that fertilization of adjacent substrates promotes belowground sod expansion and greater belowground biomass development, key to successful low Arctic restoration.

Restoring Fire Impacted Land in the Monchique Natura 2000 Site in Southwestern Portugal

In August 2018, the largest wildfire in Europe occurred in southwestern Portugal. Impacting an area of  27000 hectares covering 3 municipal councils, Monchique, Silves, and Portimão, in the Algarve of mainly privately owned land-plots within the Monchique Natura 2000. To restore this land, Ryanair, in partnership with GEOTA (a national NGO), the Monchique municipal council, Algarve Directorate for Tourism, and Algarve ICNF agency, developed the ‘Renature Monchique’ project. The aim of which is to assist landowners recover fire-impacted groves of endemic commercial trees, such as cork oak groves, including the planting of other trees, e.g., the Monchique oak, a local critically endangered species.

Starting in April 2019, the challenges and limitations for this project soon became clear. Until this time in Portugal, there had been no significant effort to initiate a ‘restoration project’ on a landscape scale with local landowners. Furthermore, a large part of the impacted area falls within a planted forest zone, and along with new fire regulations this limited tree planting options. In addition, the existing endemic tree groves are fragmented, isolated, and in many instances mere remnants of what existed previously. Also impacted by the fire of 2003, this area has suffered ecologically, socially, and economically, indicated by the high number of abandoned and degraded land-plots within this Natura 2000 site.

Primarily limited by private landownership, landscape-scale restoration poses many challenges in Portugal today. Not least of which is ‘aftercare’, limited by the options linked to available funding resources for ecological restoration in Portugal currently.

Trail degradation in Cape Breton Highlands National Park: An ecological approach to vegetation restoration

Ecotourism and hiking trails have become increasingly popular, but trails can lead to damage to surrounding vegetation, substrate compaction and erosion. Failure of vegetation recovery and further degradation has been observed at two closed sections of hiking trails in Cape Breton Highlands National Park (Skyline and Mica Hill). In the first year (Summer 2018) trail conditions, biotic factors, and abiotic factors were assessed in paired plots on the degraded trail and in adjacent undamaged vegetation. Characteristics of trail conditions were identified as lower vascular plant cover, and higher daily surface temperatures, compaction and moisture, as well as reduced substrate nutrients and higher pH levels. Additionally, there was no seed bank present on closed trails at Skyline, and while there was some evidence of a viable seed bank at Mica Hill, the seed bank species were not present in surrounding reference vegetation. In the second year, five different treatment types were implemented on closed sections of the Skyline trail and monitored for their effectiveness: erosion control mats were combined topsoil addition with additional direct seeding and transplanting treatments. While directly transplanted species were able to establish on the closed trails, the addition of topsoil improved cover and quality of vegetation. Both seeding and transplanting of native species also appeared to improve vegetation and quality when compared to controls. This study furthers our understanding of interactions between barrens species and provides the basis for a long-term restoration study where further monitoring throughout multiple growing seasons can further elucidate or modify these findings.

Drivers of Plot Scale Evapotranspiration in Restored and Unrestored Extracted Peatlands

Peat extraction alters peatland hydrology through active drainage and altered peat hydrophysical properties. Once extraction ceases, ecosystem recovery is limited by low soil moisture and deep water tables. Peatland restoration aims to return hydrologic conditions to those in undisturbed, reference peatlands. Changes to water table position, and re-introduction of plant species post-restoration, will both alter ET. Yet, how ET evolves post-restoration is poorly understood, particularly at the plot scale. In this study, ET was calculated from compiled growing season plot scale relative humidity data from restored, unrestored, and natural peatland sites in Seba Beach, Alberta and Bois-des-Bel, Quebec. Time since restoration at these sites ranged from 1 year to 25 years. The objectives of this study were to i) assess differences in ET between the three site types, ii) assess the influence of time since restoration on ET, iii) evaluate the influence of environmental controls and vegetation communities on ET. This study found that the restored sites had significantly higher ET rates than the natural and unrestored sites. There was no relationship between ET and time since restoration. Atmospheric conditions and soil temperature were important drivers of ET at all sites. Water table depth was not an important driver. The influence of vegetation differed across the sites. Gross ecosystem productivity was important at the restored and unrestored sites, while moss cover was most important at natural sites. Understanding the drivers of ET will help us better predict restored peatland water balance under a changing climate.

Fen plant re-establishment in restored peatlands on former in-situ oil sands well pad improves with residual mineral soil base and proper ecohydrological connectivity

Post-oil-mining peatland restoration aims at re-establishing crucial peatland functions, such as wildlife habitat, peat accumulation and carbon sequestration. Suitable conditions including soil moisture content near saturation via a relatively stable, near-surface water table, and abundant organic matter input are necessary to ensure the steady accumulation of peat.

We evaluated the efficiency of four restoration techniques applied on two former in-situ (“in place”) oil sands well pads in the Peace River and Cold Lake Oil Sands regions in Alberta, Canada, to provide habitat to characteristic fen plant species and plant functional types. The assessed restoration techniques were 1) the complete removal of all well pad construction materials and 2) spontaneous re vegetation, 3) the partial removal of the well pad’s mineral infill and 4) the managed re-vegetation with plant seedlings of Larix laricina, Salix lutea, and Carex aquatilis. An unrestored well pad sector and 24 local reference wetlands were monitored for comparison, considering vegetation diversity, biogeochemistry, hydrology and local climatic conditions.

Preliminary results show the highest plant diversity in the sectors with the mineral fill scraped down and levelled closest to the adjacent fen ecosystem, resulting in the water table level being closest to the surface. Lowest diversity was found in sectors of seedlings introduction, and the complete removal of all well pad construction materials. Findings suggest that the closer the surface is levelled with the surrounding ecosystems, and more seamless the hydrologic connection is re-established between restored and undisturbed sectors, the faster fen initiating conditions will establish and desired characteristic plant species will migrate.