How far is it to your local? A survey on local provenance use in New South Wales

Summary The decision as to where to source seed is one of the most critical in restoration projects. Locally collected seed is often recommended, or even contractually required, because it is assumed to be adapted to local conditions and therefore result in superior survival and growth rates, conferring a greater probability of restoration success. The perceived advantages, which include retaining the genetic ‘integrity’ of the site, are centred around the avoidance of outbreeding depression and hybridization. These traditional reasons for using locally collected seed need to be reconsidered in the light of rapidly changing climatic and other environmental conditions; plants that are locally adapted now may not be locally adapted in future. Understanding the current usage of local provenance is pivotal to discussions on its appropriateness under climate change. We present the results of a survey of restoration practitioners in New South Wales on attitudes and practices in relation to the use of local provenance. We found that whilst the majority of practitioners preferentially use local provenance seeds, the actual definition of local provenance varied amongst respondents. Whilst 80% of participants believe that projections of future climate change are relevant to restoration projects, there is an apparent reluctance to actively manage for this eventuality. However, many respondents are in favour of a review of seed‐sourcing policy/guidelines to allow for the inclusion of non‐local provenance material. Implications of the survey for potential changes to guidelines to better prepare for anticipated changing conditions are discussed.     

Combining genotype,phenotype, and environmental data to delineate site‐adjusted provenance strategies for ecological restoration

Despite the importance of climate‐adjusted provenancing to mitigate the effects of environmental change, climatic considerations alone are insufficient when restoring highly degraded sites. Here we propose a comprehensive landscape genomic approach to assist the restoration of moderately disturbed and highly degraded sites. To illustrate it we employ genomic data sets comprising thousands of single nucleotide polymorphisms from two plant species suitable for the restoration of iron‐rich Amazonian Savannas. We first use a subset of neutral loci to assess genetic structure and determine the genetic neighbourhood size. We then identify genotype‐phenotype‐environment associations, map adaptive genetic variation, and predict adaptive genotypes for restoration sites. Whereas local provenances were found optimal to restore a moderately disturbed site, a mixture of genotypes seemed the most promising strategy to recover a highly degraded mining site. We discuss how our results can help define site‐adjusted provenancing strategies, and argue that our methods can be more broadly applied to assist other restoration initiatives.     

A spatial multicriteria decision analysis for selecting priority sites for plant species restoration: a case study from the Chilean biodiversity hotspot

Developing conservation strategies to restore populations of threatened species has been signaled as an important task by the Convention on Biological Diversity 2011–2020 targets. Species are being threatened not only by habitat loss and fragmentation but increasingly by climate change. As resources for conservation are often limited, and restoration is among the most expensive conservation strategies, developing approaches that help in the prioritization of areas for restoration efforts is a critical task. In this study, we propose a spatial multicriteria decision analysis (SMCDA) framework for identifying potential areas for plant species restoration initiatives that can explicitly take into account future climatic change. As a way to show how the framework can be applied, we took advantage of freely available niche modeling software and geospatial information to identify regional‐scale priority areas for restoration of two threatened endemic tree species (i.e. Bielschmiedia miersii and Pouteria splendens) of the “Chilean Winter Rainfall‐Valdivian Forest” Hotspot. The SMCDA framework allowed us not only to identify priority areas for species restoration but also to analyze how different environmental conditions and land‐use types may affect the selection of areas for species restoration. Our analysis suggests that the inclusion of climate change is a key factor to assess the potential areas for species restoration because species may respond differentially to future climatic conditions. This framework is conceived to be used as a complementary approach to available landscape‐scale spatial conservation planning tools.     

Step back from the forest and step up to the Bonn Challenge: how a broad ecological perspective can promote successful landscape restoration

We currently face both an extinction and a biome crisis embedded in a changing climate. Many biodiverse ecosystems are being lost at far higher rates than they are being protected or ecologically restored. At the same time, natural climate solutions offer opportunities to restore biodiversity while mitigating climate change. The Bonn Challenge is a U.N. programme to restore biodiversity and mitigate climate change through restoration of the world's degraded landscapes. It provides an unprecedented chance for ecological restoration to become a linchpin tool for addressing many environmental issues. Unfortunately, the Forest and Landscape Restoration programme that underpins the Bonn Challenge, as its name suggests, remains focused on trees and forests, despite rising evidence that many non‐forest ecosystems also offer strong restoration potential for biodiversity and climate mitigation. We see a need for restoration to step back to be more inclusive of different ecosystem types and to step up to provide integrated scientific knowledge to inform large‐scale restoration. Stepping back and up will require assessments of where to restore what species, with recognition that in many landscapes multiple habitat types should be restored. In the process, trade‐offs in the delivery of different ecosystem services (e.g. carbon, biodiversity, water, albedo, livestock forage) should be clearly addressed. We recommend that biodiversity safeguards be included in policy and implemented in practice, to avoid undermining the biophysical relationships that provide ecosystem resilience to climate change. For ecological restoration to contribute to international policy goals will require integrated large‐scale science that works across biome boundaries.     

Seed planning,sourcing, and procurement

Ensuring the availability of adequate seed supplies of species and sources appropriate for restoration projects and programs necessitates extensive science‐based planning. The selection of target species requires a review of disturbance conditions and reference areas, development of a reference model, and consideration of specific objectives, timeframes, available resources, and budgets as well as the performance of prospective species in past restoration efforts. Identification of seed sources adapted to site conditions is critical to provide for short‐term establishment and long‐term sustainability. Seed zones and plant movement guidelines provide tools for sourcing plant materials with reduced risk of maladaptation. A seed zone framework also facilitates seed use planning and contributes to stability and predictability of the commercial market, thereby reducing costs and improving the availability of adapted seed supplies. Calculating the amount of seed required for each species is based on seed quality (viability, purity), seed weight, expected seedling establishment, and desired composition of the seeding. If adequate collections from wildland stands are not feasible, then seed increase in seed fields or use of nursery stock may be warranted. Adherence to seed collection and seed production protocols for conserving genetic diversity is critical to protect genetic resources and buffer new seedings and plantings against environmental stressors. Maintenance of genetic diversity becomes even more critical considering current or expected climate change impacts. Collaboration and partnerships can benefit seed selection and procurement programs through sharing of information, coordination in project planning, and increasing the availability of native seed.     

Local provenancing in subtropical rainforest restoration: For better or worse? A review of practitioners’ perspectives

The adaptive potential of restored communities is important to their long‐term sustainability, particularly in the face of changing environmental conditions such as climate change. The genetic diversity of rainforest plants in restoration projects and their suitability to current and future environmental site conditions are important considerations for restoration practitioners and seed suppliers. Presented here are the results from a survey of rainforest restoration practitioners in North East New South Wales and South East Queensland, Australia. The survey canvassed practitioners’ perspectives on local provenancing, genetic diversity and other aspects of restoration that have the potential to influence the long‐term success of restored rainforest communities. All respondents to this survey typically included a planting component in their restoration projects (whether for reconstruction or to supplement assisted regeneration). Planting represents an anthropogenic selection and translocation of genotypes to a restoration site. As a result, considerations of genetic origin and the potential implications to the restored rainforest community are relevant to most restoration projects. This industry survey's results showed that genetic diversity and local provenancing are concepts of importance to practitioners. However, there seems to be a lack of clarity within the industry about how to define local provenance and how the concepts of local provenancing and genetic diversity influence each other. The results indicated that local provenancing remains the preferred provenancing strategy amongst practitioners, with inclusion of non‐local provenance seed not regarded as an effective means of improving genetic diversity. This is despite researchers highlighting the limitations of local provenancing, particularly in highly fragmented landscapes, and despite the publication of numerous alternative provenancing strategies. Rainforest restoration may benefit from practitioners questioning the appropriateness of local provenancing to their restoration projects and considering that in some circumstances exclusive reliance on local provenance stock may in fact be worse, not better, for the long‐term sustainability of restored communities.     

Integrated climate sensitive restoration framework for transformative changes to sustainable land restoration

Sustainable land restoration is the key to restore degraded land, halt biodiversity loss, and reinstate ecosystem services for human well‐being. Restoration needs to be planned and conducted with due recognition to growing climate uncertainty with an evolved understanding of the future restoration targets. The present opinion article attempts to provide an overview on an integrated climate sensitive restoration framework that recognizes the local participation in mapping degraded lands, identification of species for supporting species modeling to better understand climate uncertainty. Involvement of citizen science‐based restoration monitoring tools can contribute to big data analytics for ecological monitoring and policy support. The Framework potentially helps in sustainable land restoration by transformative changes for achieving the UN Decade on Ecosystem Restoration (2021–2030), Sustainable Development Goals 15, and addressing the post‐2020 Global Biodiversity Framework. However, to realize success, climate finance mechanisms to drive restoration should be seriously considered for reducing bias and enhancing opportunities of equitable sharing in the era of corruption, authoritarianism, and regulatory capture.     

Assessment of population genetics and climatic variability can refine climate‐informed seed transfer guidelines

Restoration guidelines increasingly recognize the importance of genetic attributes in translocating native plant materials (NPMs). However, when species‐specific genetic information is unavailable, seed transfer guidelines use climate‐informed seed transfer zones (CSTZs) as an approximation. While CSTZs may improve how NPMs are developed and/or matched to restoration sites, they overlook genetic factors that can diminish restoration success and/or deteriorate natural patterns of genetic diversity and environmental factors that may introduce unexpected variation. Here, we analyze molecular data and geographic patterns of environmental variability across the western United States and demonstrate how they can refine CSTZs. Using genetic data available for 13 relevant plant species, we found that the probability of mixing genetically differentiated individuals (i.e. from different evolutionary lineages, or populations) was approximately 8% when considering locations separated by 50 km and reached nearly 80% by 500 km, which are distances relevant to ecoregionally constrained CSTZs. Furthermore, climate analyses revealed that geographically proximate locations are likely to maintain environmental similarity, regardless of CSTZ or ecoregion assignment. These results suggest constraining CSTZ‐informed seed transfer decisions by distance may mitigate the opportunity for negative genetic outcomes. Furthermore, environmental variability and/or specificity of NPMs (depending upon the restoration strategy) should be achieved by sourcing NPMs from geographically proximate locations to avoid introducing excessive genetic differentiation. Our results highlight the utility of combining molecular genetic data with other genetic inferences (i.e. of adaptation) to determine how best to transfer seed across restoration species' ranges and develop new restoration materials.     

Forward‐Looking Forest Restoration Under Climate Change—Are U.S. Nurseries Ready?

The pace of climate change suggests that restoration efforts once focused on past conditions should become more forward‐looking. Suggestions for such restoration emphasize the use of a suite of species adapted to a range of possible future climates. In forest restoration, opportunities for forward‐looking restoration may be limited by the availability of suitable stock from state and commercial nurseries. Presently, most state nurseries have stock potentially suited to warmer climates than currently exist in their states. However, these nurseries are generally not actively incorporating information about climate change into their stocking choices and some see clear obstacles to providing such stock, particularly uncertainty about the future climate, and the existence of seed zones and other policies designed to protect locally adapted species genetics. As restoration ecologists adapt their methods to incorporate climate change, state nurseries should be involved in those discussions and may be important partners in outreach.     

Using restoration as an experimental framework to test provenancing strategies and climate adaptability

Restoring degraded Australian landscapes through revegetation is a key concern of land holders, NGOs and government agencies. With the advent of climate change, it is increasingly important that revegetation activities take into consideration the species and provenance of plant materials to ensure that environmental plantings will be resilient to future climate conditions. A major strength of the past 30 years restoration programmes is the development of a distributed network of educated and experienced practitioners. We have recently invited stakeholders from among this network to participate in a process to cost‐effectively build Environmental Research Infrastructure – a nationally distributed network of restoration plantings that explore a broad range of research activities including a better understanding of the adaptive responses of different species and provenances. This would also facilitate long‐term monitoring of change and adaptation across Australia, providing a wealth of information to inform future conservation and restoration programmes.     

Lowland tapirs facilitate seed dispersal in degraded Amazonian forests

The forests of southeastern Amazonia are highly threatened by disturbances such as fragmentation, understory fires, and extreme climatic events. Large‐bodied frugivores such as the lowland tapir (Tapirus terrestris) have the potential to offset this process, supporting natural forest regeneration by dispersing a variety of seeds over long distances to disturbed forests. However, we know little about their effectiveness as seed dispersers in degraded forest landscapes. Here, we investigate the seed dispersal function of lowland tapirs in Amazonian forests subject to a range of human (fire and fragmentation) and natural (extreme droughts and windstorms) disturbances, using a combination of field observations, camera traps, and light detection and ranging (LiDAR) data. Tapirs travel and defecate more often in degraded forests, dispersing much more seeds in these areas [9,822 seeds per ha/year (CI_95% = 9,106; 11,838)] than in undisturbed forests [2,950 seeds per ha/year (CI_95% = 2,961; 3,771)]. By effectively dispersing seeds across disturbed forests, tapirs may contribute to natural forest regeneration—the cheapest and usually the most feasible way to achieve large‐scale restoration of tropical forests. Through the dispersal of large‐seeded species that eventually become large trees, such frugivores also contribute indirectly to maintaining forest carbon stocks. These functions may be critical in helping tropical countries to achieve their goals to maintain and restore biodiversity and its ecosystem services. Ultimately, preserving these animals along with their habitats may help in the process of natural recovery of degraded forests throughout the tropics. Abstract in Portuguese is available with online material.     

Should we be more critical of remnant seed sources being used for revegetation?

Summary A challenge for land managers restoring degraded agricultural landscapes across southern Australia will be to ensure the viability of remnant vegetation while simultaneously supplying the quantities of appropriate seed required for revegetation. To ensure such revegetation programs have the best chance of success, seed that is both genetically diverse and locally adapted will be required. Identifying suitable seed sources can be particularly difficult in regions where local seed sources are restricted to small and isolated remnants. Gold‐dust Wattle (Acacia acinacea Lindl.) is a key revegetation species in the Deniliquin region of New South Wales; however, broadscale land clearing in the area has limited local seed sources to a few remnant stands. Field‐based experience suggests that revegetation success may depend upon the source of seed used, raising the question of whether differences in the germination and survival of seed reflect functional problems within these source populations. To test this possibility, seed was collected from 15 mothers in each of three seed sources regularly used for local restoration programs. Seed quality for each mother was assessed in terms of seed production and seedling fitness. In addition, genetic diversity and mating system parameters were determined to assess whether these explained the seed quality responses observed. Differences among the seed sources with respect to seed quality were generally congruent with field‐based predictions. High levels of correlated paternity in the two poorly performing seed sources probably reflect limited mating availability due to smaller population sizes and genetic incompatibility being mediated by a self‐incompatible reproductive strategy. Further research is now required to determine whether observed variability in the quality of seed from remnant vegetation in degraded landscapes is compromising revegetation efforts, and to help practitioners develop strategies to critically evaluate their seed sources.     

Application of a Gondwanan perspective to restore ecological integrity in the south‐western Australian global biodiversity hotspot

Bounded by ocean and desert, the isolated, predominately Mediterranean‐climate region of south‐western Australia (SWA) includes nine bioregions (circa 44 million hectares). The ecological integrity of the landscapes in this global biodiversity hotspot has been compromised by deforestation, fragmentation, exploitation, and introduced biota. Nature and degree of transformation varies between four interconnected landscapes (Swan Coastal Plain; South‐west Forests; Wandoo Woodlands; and Great Western Woodlands). A Gondwanan perspective emphasizes a venerable biota and a cultural component to deep time. The particular importance of remnants and protected areas is recognized in restoring ecological integrity to Gondwanan landscapes. The nature and magnitude of the restoration task in these ancient, and neighboring, landscapes require higher levels of investment and more time than do recent landscapes. The protection, conservation, restoration, and rehabilitation of ecological integrity require multiple approaches in each landscape as well as consideration of the whole. Active conservation of biota and minimizing the impact of industrial‐ and agricultural‐use are priorities. Integrating a climate focus and rethinking fire are critical restoration considerations to future trajectories under anthropogenic climate change. A legislative mandate to coordinate industrial‐scale restoration and active conservation to build from protected areas must become a societal priority to restore ecological integrity.     

Genetic Delineation of Local Provenance in Persoonia longifolia: Implications for Seed Sourcing for Ecological Restoration

Restoration of diverse native plant communities typically requires the collection of large amounts of seed. Thus, practitioners often struggle to find adequate supplies near project sites and need to know from how far they can collect without compromising restoration success—how far does local provenance extend? We addressed this issue by assessing genetic variation within, and differentiation among, 12 potential seed source populations of Persoonia longifolia, a key component of the jarrah forest of Western Australia. An analysis of molecular variance of 66 polymorphic amplified fragment length polymorphism markers partitioned 92% of the total genetic variation within populations and 8% among populations, indicating relatively weak but statistically significant population genetic differentiation. Ordination of these genetic data showed marked west/east and north/south gradients. Pairwise population genetic dissimilarity was correlated with both geographic distance and environmental distance derived from five climate variables. However, partial Mantel tests showed that the relationship between genetic and geographic distance was not independent of environmental distance, suggesting a non‐neutral signature in these markers. Bayesian outlier analysis identified two markers, and spatial analysis method tests identified highly significant associations between these two markers and three environmental variables. Frequency differences at these markers across populations suggested the possibility of climatically adapted provenances. The global significance value from analyses of similarities for these two markers correlated to a general provenance distance of 47 km, in contrast to a threshold of 60 km for the complete dataset. Guidelines for seed sourcing that consider these population genetic data should lead to more effective ecological restoration with this species.     

Integrating a global agro-climatic classification with bioregional boundaries in Australia

Aim Stratification of major differences in the biophysical features of landscapes at the continental scale is necessary to collectively assess local observations of landscape response to management actions for consistency and difference. Such a stratification is an important step in the development of generalizations concerning how landscapes respond to different management regimes. As part of the development of a comparative framework for this purpose, we propose a climate classification adapted from an existing broad scale global agro‐climatic classification, which is closely aligned with natural vegetation formations and common land uses across Australia. Location The project considered landscapes across the continent of Australia. Methods The global agro‐climatic classification was adapted by using elevation‐dependent thin plate smoothing splines to clarify the spatial extents of the 18 global classes found in Australia. The clarified class boundaries were interpolated from known classes at 822 points across Australia. These classes were then aligned with the existing bioregional classification, Interim Biogeographic Regionalization for Australia IBRA 5.1. Results The aligned climate classes reflect major patterns in plant growth temperature and moisture indices and seasonality. These in turn reflect broad differences in cropping and other land use characteristics. Fifty‐two of the 85 bioregions were classified entirely into one of the 18 agro‐climatic classes. The remaining bioregions were classified according to sub‐bioregional boundaries. A small number of these sub‐bioregions were split to better reflect agro‐climatic boundaries. Main conclusions The agro‐climatic classification provided an explicit global context for the analysis. The topographic dependence of the revised climate class boundaries clarified the spatial extents of poorly sampled highland classes and facilitated the alignment of these classes with the bioregional classification. This also made the classification amenable to explicit application. The bioregional and subregional boundaries reflect discontinuities in biophysical features. These permit the integrated classification to reflect major potential differences in landscape function and response to management. The refined agro‐climatic classification and its integration with the IBRA bioregions are both available for general use and assessment.     

Natural regeneration in the context of large‐scale forest and landscape restoration in the tropics

Large‐scale and long‐term restoration efforts are urgently needed to reverse historical global trends of deforestation and forest degradation in the tropics. Restoration of forests within landscapes offers multiple social, economic, and environmental benefits that enhance lives of local people, mitigate effects of climate change, increase food security, and safeguard soil and water resources. Despite rapidly growing knowledge regarding the extent and feasibility of natural regeneration and the environmental and economic benefits of naturally regenerating forests in the tropics, tree planting remains the major focus of restoration programs. Natural regeneration is often ignored as a viable land‐use option. Here, we assemble a set of 16 original papers that provide an overview of the ecological, economic, and social dimensions of forest and landscape restoration (FLR), a relatively new approach to forest restoration that aims to regain ecological integrity and enhance human well‐being in deforested or degraded forest landscapes. The papers describe how spontaneous (passive) and assisted natural regeneration can contribute to achieving multiple social and ecological benefits. Forest and landscape restoration is centered on the people who live and work in the landscape and whose livelihoods will benefit and diversify through restoration activities inside and outside of farms. Given the scale of degraded forestland and the need to mitigate climate change and meet human development needs in the tropics, harnessing the potential of natural regeneration will play an essential role in achieving the ambitious goals that motivate global restoration initiatives.     

Intraspecific trait variation across elevation predicts a widespread tree species' climate niche and range limits

Global change is widely altering environmental conditions which makes accurately predicting species range limits across natural landscapes critical for conservation and management decisions. If climate pressures along elevation gradients influence the distribution of phenotypic and genetic variation of plant functional traits, then such trait variation may be informative of the selective mechanisms and adaptations that help define climatic niche limits. Using extensive field surveys along 16 elevation transects and a large common garden experiment, we tested whether functional trait variation could predict the climatic niche of a widespread tree species (Populus angustifolia) with a double quantile regression approach. We show that intraspecific variation in plant size, growth, and leaf morphology corresponds with the species' total climate range and certain climatic limits related to temperature and moisture extremes. Moreover, we find evidence of genetic clines and phenotypic plasticity at environmental boundaries, which we use to create geographic predictions of trait variation and maximum values due to climatic constraints across the western US. Overall, our findings show the utility of double quantile regressions for connecting species distributions and climate gradients through trait‐based mechanisms. We highlight how new approaches like ours that incorporate genetic variation in functional traits and their response to climate gradients will lead to a better understanding of plant distributions as well as identifying populations anticipated to be maladapted to future environments.     

Integrating climate change and habitat fragmentation to identify candidate seed sources for ecological restoration

Anthropogenic change (climate change and habitat fragmentation) is driving a growing view that local seed collections may need to be supplemented with nonlocal seed as a strategy to bolster genetic diversity and thus increase evolutionary potential of plantings. While this strategy is becoming widely promoted, empirical support is limited, and there is a lack of accessible research tools to assist in its experimental testing. We therefore provide the Provenancing Using Climate Analogues (PUCA) framework that integrates the principles of the climate‐adjusted provenancing strategy with concepts from population genetics (i.e. potential inbreeding in small fragmented populations) as both a research and operational‐ready tool to guide the collection of nonlocal seed. We demonstrate the application of PUCA using the Midlands of Tasmania, Australia, a region that is currently undergoing large‐scale ecological restoration. We highlight multiple nonlocal seed sources for testing by identifying actual species distribution records that currently occupy environments similar to that projected to occur at the restoration site in the future. We discuss the assumptions of PUCA and the ecological considerations that need to be tested when moving nonlocal genotypes across the landscape.     

Developing biodiverse plantings suitable for changing climatic conditions 2: Using the Atlas of Living Australia

Summary There has been an increasing investment of taxpayer dollars in revegetation in Australia over the past 20 years, at both federal and state levels. The largest of these, the Australian Government’s Biodiversity Fund, will invest A$946 million to revegetate, rehabilitate and restore landscapes to store carbon, enhance biodiversity and build environmental resilience under climate change. The universal challenge for restoration practitioners working within these programmes is species selection for both current and future environmental conditions at a given site. For policy makers, the challenge is to provide guidelines and tools for this process. The first paper in this series of two papers looked at scientific methods that could provide underpinning knowledge to improve the assessment of species vulnerability to climatic and atmospheric change. In this paper, the publically accessible Atlas of Living Australia is used to demonstrate how revegetation project leaders can assess whether the species and provenances used in their revegetation projects are likely to be suitable for changing environmental conditions. While using the Atlas can assist current selections, ways in which more reliable selections for changing climatic conditions could be made are also outlined.