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European beech (Fagus sylvatica L.) forests have recently experienced severe diebacks that are expected to increase in future. Oriental beech (Fagus sylvatica spp. orientalis (Lipsky) Greut. & Burd) is a potential candidate for assisted migration (AM) in European forests due to its greater genetic diversity and potentially higher drought resistance. Yet AM entails not only benefits, but also risks, and it is therefore important to monitor the progression of introduced (sub)species. Here, we demonstrate the potential of leaf spectroscopy to replace resource-intensive genetic analysis and field phenotyping for the discrimination and characterization of these two beech subspecies. We studied two European beech forests, one in France and one in Switzerland, where Oriental beech from the Greater Caucasus was introduced over 100 years ago. During two summers (2021, 2022), we measured leaf spectral reflectance, leaf morphological and biochemical traits from genotyped adult trees. Subspecies prediction models were developed separately for top-of-canopy leaves (amenable to remote sensing) and bottom-of-canopy leaves (easier to harvest) using partial least squares discriminant analysis (PLS-DA) and different sets of spectral predictors. Morphological, biochemical and spectra-derived leaf traits indicated that Oriental beech trees at the sites studied were characterized by higher lignin and nitrogen per unit leaf area than European beech, suggesting more protein-rich leaves on a per-area basis. The model based on top-of-canopy leaf reflectance spectra in the short-wave-infrared region (SWIR I: 1450–1750 nm) most accurately distinguished Oriental from European beech (BA = 0.86 ± 0.08, k = 0.72 ± 0.15), closely followed by models based on SWIR II, and on spectra-derived traits (BA ≥ 0.84, k ≥ 0.67). This study provides a proof-of-principle for the development of spectroscopy-based approaches when monitoring introduced species, subspecies or provenances. Our findings hold promise

Global warming may force montane species to shift upward to keep pace with their shifting climate niche. How species differences in such distribution shifts depend on their elevational positions, elevation-dependent warming rates, and other environmental constraints, or plant functional traits is poorly understood. Here, we analyzed for 137 Himalayan tree species how distribution shifts vary with elevational niche positions, environmental constraints, and their functional traits. We developed ecological niche models using MaxEnt by combining species survey and botanical collections data with 19 environmental predictors. Species distributions were projected to 1985 and 2050 conditions, and elevational range parameters and distribution areas were derived. Under the worst-case RCP 8.5 scenario, species are predicted to shift, on average, 3 m/year in optimum elevation, and have 33% increase in distribution area. Highland species showed faster predicted elevational shifts than lowland species. Lowland and highland species are predicted to expand in distribution area in contrast to mid-elevation species. Tree species for which species distribution models are driven by responses to temperature, aridity, or soil clay content showed the strongest predicted upslope shifts. Tree species with conservative trait values that enable them to survive resource poor conditions (i.e., narrow conduits) showed larger predicted upslope shifts than species with wide conduits. The predicted average upslope shift in maximum elevation (8 m/year) is >2 times faster than the current observations indicating that many species will not be able to track climate change and potentially go extinct, unless they are supported by active conservation measures, such as assisted migration. Abstract in Nepali is available with online material.

Many species are shifting their ranges to keep pace with climate change, but habitat fragmentation and limited dispersal could impede these range shifts. In the case of climate-vulnerable foundation species such as tropical reef corals and temperate forest trees, such limitations might put entire communities at risk of extinction. Restoring connectivity through corridors, stepping-stones or enhanced quality of existing patches could prevent the extinction of several species, but dispersal-limited species might not benefit if other species block their dispersal. Alternatively, managers might relocate vulnerable species between habitats through assisted migration, but this is generally a species-by-species approach. To evaluate the relative efficacy of these strategies, we simulated the climate-tracking of species in randomized competitive metacommunities with alternative management interventions. We found that corridors and assisted migration were the most effective strategies at reducing extinction. Assisted migration was especially effective at reducing the extinction likelihood for short-dispersing species, but it often required moving several species repeatedly. Assisted migration was more effective at reducing extinction in environments with higher stochasticity, and corridors were more effective at reducing extinction in environments with lower stochasticity. We discuss the application of these approaches to an array of systems ranging from tropical corals to temperate forests. This article is part of the theme issue 'Ecological complexity and the biosphere: the next 30 years'.

Many species are shifting their ranges to keep pace with climate change, but habitat fragmentation and limited dispersal could impede these range shifts. In the case of climate-vulnerable foundation species such as tropical reef corals and temperate forest trees, such limitations might put entire communities at risk of extinction. Restoring connectivity through corridors, stepping-stones or enhanced quality of existing patches could prevent the extinction of several species, but dispersal-limited species might not benefit if other species block their dispersal. Alternatively, managers might relocate vulnerable species between habitats through assisted migration, but this is generally a species-by-species approach. To evaluate the relative efficacy of these strategies, we simulated the climate-tracking of species in randomized competitive metacommunities with alternative management interventions. We found that corridors and assisted migration were the most effective strategies at reducing extinction. Assisted migration was especially effective at reducing the extinction likelihood for short-dispersing species, but it often required moving several species repeatedly. Assisted migration was more effective at reducing extinction in environments with higher stochasticity, and corridors were more effective at reducing extinction in environments with lower stochasticity. We discuss the application of these approaches to an array of systems ranging from tropical corals to temperate forests. This article is part of the theme issue 'Ecological complexity and the biosphere: the next 30 years'.

Tree species diversity is an important determinant of the capacity of forests to support biodiversity and provide multiple ecosystem services. Tree diversity is also an important determinant of the ecological stability or vulnerability of the forests against disturbances, such as insect outbreaks or pathogen epidemics. Forest management decisions regarding the tree species diversity are therefore at the very core of successful adaptation of forestry to climate change and for sustainable forest management to meet the energy and raw material needs of the circular bioeconomy. In this chapter, we focus on three strategies that have been suggested as measures for adapting the forest management to climate change and that have the potential to influence tree diversity in forests, viz. introduction of diversity using non-native tree species, assisted migration, or use of admixtures. We discuss the forest health risks of these strategies and some avenues that can help to mitigate these risks in future forest management.

Tree species diversity is an important determinant of the capacity of forests to support biodiversity and provide multiple ecosystem services. Tree diversity is also an important determinant of the ecological stability or vulnerability of the forests against disturbances, such as insect outbreaks or pathogen epidemics. Forest management decisions regarding the tree species diversity are therefore at the very core of successful adaptation of forestry to climate change and for sustainable forest management to meet the energy and raw material needs of the circular bioeconomy. In this chapter, we focus on three strategies that have been suggested as measures for adapting the forest management to climate change and that have the potential to influence tree diversity in forests, viz. introduction of diversity using non-native tree species, assisted migration, or use of admixtures. We discuss the forest health risks of these strategies and some avenues that can help to mitigate these risks in future forest management.

Biological invasions are a major global threat to biodiversity and often affect ecosystem services negatively. They are particularly problematic on oceanic islands where there are many narrow-ranged endemic species, and the biota may be very susceptible to invasion. Quantifying and mapping invasion processes are important steps for management and control but are challenging with the limited resources typically available and particularly difficult to implement on oceanic islands with very steep terrain. Remote sensing may provide an excellent solution in circumstances where the invading species can be reliably detected from imagery. We here develop a method to map the distribution of the alien chestnut (Castanea sativa Mill.) on the island of La Palma (Canary Islands, Spain), using freely available satellite images. On La Palma, the chestnut invasion threatens the iconic laurel forest, which has survived since the Tertiary period in the favourable climatic conditions of mountainous islands in the trade wind zone. We detect chestnut presence by taking advantage of the distinctive phenology of this alien tree, which retains its deciduousness while the native vegetation is evergreen. Using both Landsat 8 and Sentinel-2 (parallel analyses), we obtained images in two seasons (chestnuts leafless and in-leaf, respectively) and performed image regression to detect pixels changing from leafless to in-leaf chestnuts. We then applied supervised classification using Random Forest to map the present-day occurrence of the chestnut. Finally, we performed species distribution modelling to map the habitat suitability for chestnut on La Palma, to estimate which areas are prone to further invasion. Our results indicate that chestnuts occupy 1.2% of the total area of natural ecosystems on La Palma, with a further 12–17% representing suitable habitat that is not yet occupied. This enables targeted control measures with potential to successfully manage the invasion, given the relatively l

Standing genetic variation represents a genetic load on population fitness but can also support a rapid response to short-term environmental change, and the greatest potential source of such standing genetic variation typically exists among locally adapted populations living along an environmental gradient. Here, we develop a spatially explicit simulation model to quantify the contribution of existing genetic variation arising from migration-mutation-selection-drift balance to time to extinction under environmental change. Simulations reveal that local adaptation across a species range associated with an underlying environmental gradient could extend time to extinction by nearly threefold irrespective of the rate of environmental change. The potential for preadapted alleles to increase the rate of adaptation changes the relative importance of established extinction risk factors; in particular, it reduced the importance of the breadth of environmental tolerance and it increased the relative importance of fecundity. Although migration of preadapted alleles generally increased persistence time, it decreased it at rates of environmental change close to the critical rate of change by creating a population bottleneck, which ultimately limited the rate at which de novo mutations could arise. An analysis of the extinction dynamics further revealed that one consequence of gene flow is the potential to maximize population growth rate in at least part of the species range, which is likely to have consequences for forecasting the consequences of ecological interactions. Our study shows that predictions of persistence time change fundamentally when existing local adaptations are explicitly taken into account, underscoring the need to preserve and manage genetic diversity.

Standing genetic variation represents a genetic load on population fitness but can also support a rapid response to short-term environmental change, and the greatest potential source of such standing genetic variation typically exists among locally adapted populations living along an environmental gradient. Here, we develop a spatially explicit simulation model to quantify the contribution of existing genetic variation arising from migration-mutation-selection-drift balance to time to extinction under environmental change. Simulations reveal that local adaptation across a species range associated with an underlying environmental gradient could extend time to extinction by nearly threefold irrespective of the rate of environmental change. The potential for preadapted alleles to increase the rate of adaptation changes the relative importance of established extinction risk factors; in particular, it reduced the importance of the breadth of environmental tolerance and it increased the relative importance of fecundity. Although migration of preadapted alleles generally increased persistence time, it decreased it at rates of environmental change close to the critical rate of change by creating a population bottleneck, which ultimately limited the rate at which de novo mutations could arise. An analysis of the extinction dynamics further revealed that one consequence of gene flow is the potential to maximize population growth rate in at least part of the species range, which is likely to have consequences for forecasting the consequences of ecological interactions. Our study shows that predictions of persistence time change fundamentally when existing local adaptations are explicitly taken into account, underscoring the need to preserve and manage genetic diversity.

Standing genetic variation represents a genetic load on population fitness but can also support a rapid response to short-term environmental change, and the greatest potential source of such standing genetic variation typically exists among locally adapted populations living along an environmental gradient. Here, we develop a spatially explicit simulation model to quantify the contribution of existing genetic variation arising from migration-mutation-selection-drift balance to time to extinction under environmental change. Simulations reveal that local adaptation across a species range associated with an underlying environmental gradient could extend time to extinction by nearly threefold irrespective of the rate of environmental change. The potential for preadapted alleles to increase the rate of adaptation changes the relative importance of established extinction risk factors; in particular, it reduced the importance of the breadth of environmental tolerance and it increased the relative importance of fecundity. Although migration of preadapted alleles generally increased persistence time, it decreased it at rates of environmental change close to the critical rate of change by creating a population bottleneck, which ultimately limited the rate at which de novo mutations could arise. An analysis of the extinction dynamics further revealed that one consequence of gene flow is the potential to maximize population growth rate in at least part of the species range, which is likely to have consequences for forecasting the consequences of ecological interactions. Our study shows that predictions of persistence time change fundamentally when existing local adaptations are explicitly taken into account, underscoring the need to preserve and manage genetic diversity.

Standing genetic variation represents a genetic load on population fitness but can also support a rapid response to short-term environmental change, and the greatest potential source of such standing genetic variation typically exists among locally adapted populations living along an environmental gradient. Here, we develop a spatially explicit simulation model to quantify the contribution of existing genetic variation arising from migration-mutation-selection-drift balance to time to extinction under environmental change. Simulations reveal that local adaptation across a species range associated with an underlying environmental gradient could extend time to extinction by nearly threefold irrespective of the rate of environmental change. The potential for preadapted alleles to increase the rate of adaptation changes the relative importance of established extinction risk factors; in particular, it reduced the importance of the breadth of environmental tolerance and it increased the relative importance of fecundity. Although migration of preadapted alleles generally increased persistence time, it decreased it at rates of environmental change close to the critical rate of change by creating a population bottleneck, which ultimately limited the rate at which de novo mutations could arise. An analysis of the extinction dynamics further revealed that one consequence of gene flow is the potential to maximize population growth rate in at least part of the species range, which is likely to have consequences for forecasting the consequences of ecological interactions. Our study shows that predictions of persistence time change fundamentally when existing local adaptations are explicitly taken into account, underscoring the need to preserve and manage genetic diversity.

Serbian spruce is an old, relict and currently rare and endangered spruce species particularly susceptible to climate change that attracts a lot of attention in the academic community since its discovery in 1875. Today, Serbian spruce is limited to the area of ~100 km2 localized around the mid-course of the Drina River in the mountainous central Balkans, at the border of Republic of Serbia and Republic of Srpska, Bosnia and Herzegovina. Within this small area, ~30 remnant populations of various sizes are scattered at north-to-northwest orientated slopes of hills. Given the current state of Serbian spruce populations as well as extreme climate events and poor natural regeneration in this species, applied “do not touch” conservation approach is severely questioned, and some alternative protection and in situ and ex situ conservation actions have been put forward. In situ actions should involve: (1) facilitation of natural regeneration by selective removal of individual competitor trees, (2) assisted natural regeneration by planting high quality seedlings throughout the species current natural range or at nearby suitable sites, and (3) assisted natural regeneration by direct seeding. Although in situ actions may provide short-term persistence of Serbian spruce, ex situ actions, i.e., assisted migration, achieved by both assisted range expansion and assisted species migration, are inevitable, since it is very likely that Serbian spruce will disappear from its natural habitats in the near future due to the rapid climate change.

Standing genetic variation represents a genetic load on population fitness but can also support a rapid response to short-term environmental change, and the greatest potential source of such standing genetic variation typically exists among locally adapted populations living along an environmental gradient. Here, we develop a spatially explicit simulation model to quantify the contribution of existing genetic variation arising from migration-mutation-selection-drift balance to time to extinction under environmental change. Simulations reveal that local adaptation across a species range associated with an underlying environmental gradient could extend time to extinction by nearly threefold irrespective of the rate of environmental change. The potential for preadapted alleles to increase the rate of adaptation changes the relative importance of established extinction risk factors; in particular, it reduced the importance of the breadth of environmental tolerance and it increased the relative importance of fecundity. Although migration of preadapted alleles generally increased persistence time, it decreased it at rates of environmental change close to the critical rate of change by creating a population bottleneck, which ultimately limited the rate at which de novo mutations could arise. An analysis of the extinction dynamics further revealed that one consequence of gene flow is the potential to maximize population growth rate in at least part of the species range, which is likely to have consequences for forecasting the consequences of ecological interactions. Our study shows that predictions of persistence time change fundamentally when existing local adaptations are explicitly taken into account, underscoring the need to preserve and manage genetic diversity.

‘Putting the right species back in the right place’: expressed in the words of Bruce Pavlik, the Head of Restoration Ecology at the Millennium Seed Bank at Kew Gardens in a fundraising clip for the Breathing Planet Campaign, the work of biodiversity repositories seems straightforward. A simple matter of renewing the colonial and capitalistic capture of nature by exhausting its diversity in collecting, and then of reinserting species, suspended in the form of genetic information, into the neat spaces their disappearance or almost-dispappearance has left in their original ecosystems, the redemptive value of biodiversity repositories seems unquestionable. ‘There is no technological reason why any species should go extinct’, the clip goes on. The cryopreservation of genetic material in seed banks and ‘frozen zoos’ is often and justifiably understood as genetic-fetishistic suspension, several times removed from animal lives in actual habitats; I propose however to read them as world-making devices in their own right too, more entangled and entangling than they might present themselves to be. Collecting and saving are two mandates that have effects both on the species whose genetic information is banked and on the natures that are made possible or impossible through the projects delineated by biodiversity repositories; but they have also been implicated in a third such mandate, the assisted adaptation of species to anthropogenic climate change (be it the plan for ‘chaperoned assisted relocation’ proposed by the Missouri Botanical Garden or the ‘cultivation of marginally hardy taxa’ proposed at the Arnold Arboretum). How are biodiversity repositories an active intervention into the shaping of natures both inside and outside, and what are the consequences of what happens within the apparatus of these repositories for wider understandings of landscapes and species under threat? How linked is the suspension of metabolic processes and evolutionary potential and the understandi

Key message: This datapaper collects individual georeferenced tree height data from Pinus nigraArn.,P. pinasterAiton, andP. pineaL. planted in common gardens in France, Germany, Morocco, and Spain. The data can be used to assess genetic variation and phenotypic plasticity with further applications in biogeography and forest management. The three datasets are available at https://doi.org/10.5281/zenodo.3250704(Vizcaíno-Palomar et al.2018a),https://doi.org/10.5281/zenodo.3250698(Vizcaíno-Palomar et al.2018b), andhttps://doi.org/10.5281/zenodo.3250707(Vizcaíno-Palomar et al. 2018c), and the associated metadata are available at https://metadata-afs.nancy.inra.fr/geonetwork/srv/eng/catalog.search#/metadata/644682d3-78c6-4fcc-af26-b1a928be7b1b,https://metadata-afs.nancy.inra.fr/geonetwork/srv/eng/catalog.search#/metadata/535b8ad0-9315-4d78-80bd-d0f6cbb9d0ceandhttps://metadata-afs.nancy.inra.fr/geonetwork/srv/eng/catalog.search#/metadata/4cc0d2f0-00a9-42c8-aa34-fbbc647e3eb9forP. nigra, P. pinasterandP. pinea, respectively.

[EN] In the mid-twentieth century, the overseas emigration from Europe was in clear decline, but both Spain and Argentina tried to revitalize this flow that had carried thousands of families to the South American country decades earlier. Owing to economic, political and ideological reasons, both governments allocated an enormous amount of resources to fostering this migratory movement, a goal in which the Intergovernmental Committee for European Migration (ICEM) was also involved. Thanks to this assistance, many Spanish families with no resources were able to emigrate and settle in Argentinean territory. However, not everything turned into benefits for the migrants. The implemented plans also suffered from serious defects that, in many cases, caused more difficulties than they tried to solve. In this paper, we will analyze these problems and the attempts to resolve them., [ES] A mediados del siglo XX, pese a los claros síntomas de declive de la emigración europea hacia ultramar, tanto España como Argentina intentaron revitalizar la corriente que décadas antes había llevado a miles de familias a establecerse en el país sudamericano. Por motivos económicos, políticos e ideológicos, ambos gobiernos dedicaron una ingente cantidad de recursos a fomentar este movimiento migratorio, objetivo en el que también estaba volcado el Comité Intergubernamental para las Migraciones Europeas (CIME), un organismo cuya existencia dependía precisamente del mantenimiento de los flujos transoceánicos. Gracias a esta asistencia, muchas familias españolas sin recursos pudieron emigrar y establecerse en territorio argentino, pero no todo se tradujo en beneficios para los migrantes. Los programas de mano de obra y de reagrupación familiar, a los que estos se acogieron, adolecían de defectos que en muchos casos terminaron causando problemas más graves de los que pretendían solventar. En el presente artículo se analizarán estos problemas y los intentos de solución por parte de sus responsables.

This study aims at investigating how diversity and community structure of arthropods are affected by assisted migration of foundation species. This is proposed to counter biodiversity loss in the tracks of climate change. By focusing on foundation species, a larger quantity of biodiversity could be protected. I investigated arthropod diversity and community structure linked to nine Freemont cottonwood (Populus fremontii) populations types from different areas planted in three common gardens at different elevations. In accordance with the mid-elevation hypothesis that states that diversity peaks at mid-elevations, the diversity and most abundances of arthropod peaked in a mid-elevation garden at 1000 m.a.s.l. However, abundances of the functional group of predators peaked at low elevations contradicting the mid-elevation diversity pattern. Earlier studies have found that genetics and local adaptation exists between arthropods and host plants. Therefore, it was hypothesized that arthropod diversity would differ between cottonwood populations with different origin. The results were non-significant but there were signs of some cottonwood populations holding a higher diversity of arthropods. The result was inconclusive although there were signs of some populations supporting higher diversities than the rest. There was an interaction effect between common gardens and cottonwood population where the most abundant population types contained higher abundances of arthropods in mid-elevation garden. The analysis were performed with a GLM (Generalized linear model) and a Tukey HSD (honest significant difference) and the variables tested was SWD Index (Shannon-Winer diversity index), Evenness and abundances. The results from this study implement that the success of assisted migration and interaction with diversity linked to foundation species need to be further investigated. The findings in this study could be the result of a variety of underlying processes, from species interac

The Planet has entered a new epoch - the Anthropocene; where human activities, such as mining for and burning of fossil fuels, land-use change, and industrialization are actively disrupting the planet’s state. The rate at which climate change is occurring as a result of human activity is unprecedented in recent millennia and poses many threats through drastic changes in rain fall patterns, rising sea level, retreating glaciers, and an increase in extreme weather events. Mountain ranges and the plant and animal species that thrive in specific ‘life zones’ on the mountain slope are particularly vulnerable to the threats posed by climate change. As temperatures increase, these ‘life zones’ will essentially shift upwards - and flora and fauna either adapt to warmer conditions, or migrate to avoid extinction. This begs the questions, where will species retreat to when there is nowhere further up the mountain to migrate? Assisted migration has been proposed as a potential solution for species unable to adapt to climate change or unable to migrate, and involves the deliberate interference of humans in relocating species to habitats, outside their historic range, in hopes of preventing the species from going extinct. I examined key patterns within assisted migration research from peer-reviewed literature, to highlight the current state of assisted migration research and debate. My aim is to identify whether research favored certain species or geographic locations, to highlight the ethical dilemmas associated with engineering nature, and the potential assisted migration has for sustainable development in mountain ranges. I conducted a literature review and content analysis of 68 journal articles. The results suggest that assisted migration research is heavily debated from scientific, ethical, political and economic perspectives; with a largely theoretical debate and with limited transfer into field experiments. Furthermore, there is an element of bias in research focusing on

Vulnerability assessments can provide useful information for the establishment of climate change adaptation strategies. We performed spatial vulnerability assessments for multiple plant species that incorporate potential range shifts to areas of future suitable climate. We conducted the assessments at a national level for plant species organized into vulnerable species groups. We then identified a climate meta-corridor for each vulnerable group that could potentially be a pathway for multiple species. We estimated climate suitability for 2297 South Korean terrestrial plant species under current climate conditions and climate projections for 2050 using the Multivariate Adaptive Regression Splines multiresponse species distribution model. We classified the plants into five groups based on their current spatial distribution patterns: centrally located species, wide-range species, coastal mountain species, montane species, and lowland species. Three vulnerability assessment components — exposure, spatial disruption, and dispersal pressure — were used to calculate the spatial vulnerability of each species. Vulnerability values were averaged by group. We identified climate meta-corridors that would link current suitable areas to future climatically suitable areas, and tested the corridors for multi-species accessibility. The vulnerability assessment indicates that coastal mountain, montane, and lowland species groups, comprising 37% of all modelled species, are the most vulnerable to climate change. The climate meta-corridor for each group overlaps at least some portion of 83% or more of its species' current modelled ranges. The current and future climate-suitable areas for the lowland species group have very little spatial overlap, suggesting a high priority should be placed on the corridor identified for these species. We found that the destinations of the climate corridors converge, raising questions about large numbers of species moving to limited areas, and that tran

The Planet has entered a new epoch - the Anthropocene; where human activities, such as mining for and burning of fossil fuels, land-use change, and industrialization are actively disrupting the planet’s state. The rate at which climate change is occurring as a result of human activity is unprecedented in recent millennia and poses many threats through drastic changes in rain fall patterns, rising sea level, retreating glaciers, and an increase in extreme weather events. Mountain ranges and the plant and animal species that thrive in specific ‘life zones’ on the mountain slope are particularly vulnerable to the threats posed by climate change. As temperatures increase, these ‘life zones’ will essentially shift upwards - and flora and fauna either adapt to warmer conditions, or migrate to avoid extinction. This begs the questions, where will species retreat to when there is nowhere further up the mountain to migrate? Assisted migration has been proposed as a potential solution for species unable to adapt to climate change or unable to migrate, and involves the deliberate interference of humans in relocating species to habitats, outside their historic range, in hopes of preventing the species from going extinct. I examined key patterns within assisted migration research from peer-reviewed literature, to highlight the current state of assisted migration research and debate. My aim is to identify whether research favored certain species or geographic locations, to highlight the ethical dilemmas associated with engineering nature, and the potential assisted migration has for sustainable development in mountain ranges. I conducted a literature review and content analysis of 68 journal articles. The results suggest that assisted migration research is heavily debated from scientific, ethical, political and economic perspectives; with a largely theoretical debate and with limited transfer into field experiments. Furthermore, there is an element of bias in research focusing on

Climate change is projected to have negative implications for forest ecosystems and their dependent communities and industries. Adaptation studies of forestry practices have focused on maintaining the provisioning of ecosystem services; however, those practices may have implications for climate change mitigation as well by increasing biological sinks or reducing emissions. Assessments of the effectiveness of adaptation strategies to mitigate climate change are therefore needed; however, they have not been done for the world’s northern coniferous forests. Diversifying the forest by planting tree species more likely suited to a future climate is a potential adaptation strategy to increase resilience. The efficacy of this strategy to reduce the risks of climate change is uncertain, and other ecosystem services provided by the forest are also likely to be affected. We used a spatially explicit forest landscape modeling framework (LANDIS-II) to simulate the effects of planting a range of native tree species in colder areas than where they are currently planted in a managed temperate coniferous forest landscape in British Columbia, Canada. We investigated impacts on carbon pools, fluxes, tree species diversity, and harvest levels under different climate scenarios for 100 yr (2015–2115) and found that the capacity of our forest landscape to sequester carbon would largely depend on the precipitation rates in the future, rather than on temperature. We further found that, irrespective of the climate prediction model, current planting standards led to relatively low levels of resilience as indicated by carbon fluxes and stocks, net primary productivity (NPP), and species diversity. In contrast, planting a mix of alternative tree species was generally superior in increasing the resilience indicators: carbon stocks and fluxes, NPP, and tree species diversity, but not harvest rates. The second best novel planting regime involved adding Pinus contorta to the stocking standard in t

Periods of low precipitation and increasing atmospheric temperature are having adverse effects on tree and forest growth and survival in part via limitations upon photosynthesis. Understanding how different species and plant functional types will physiologically respond to the combination of drought and heat is therefore critical for modeling and predicting the fate of trees and forests under future climate conditions. In addition, climate is changing at a faster pace than the slow natural adjustment rates of most species to their rapidly shifting habitat conditions, especially for long-lived tree species, which poses a major challenge for management, conservation, and preservation strategies and policies. Therefore the current traditional conservation/preservation methods, such as providing migration corridors and increasing suitable habitat at range margins will need to be supplemented with a more direct, innovative, and adaptive approach. One such approach is that of managed migration, which is the intentional translocation of species outside their current habitat in order to reduce anticipated loss of biodiversity caused by climate change related stress. This dissertation addresses these problems through the experimental examination of heat, drought, and the combination of heat and drought on two conifer species that have differing drought tolerances, which can serve as global models for a range of physiological mechanisms to deal with water and heat stress, as well as a social science investigation into the preservation of an iconic conifer tree, the coast redwood into Oregon via managed migration.

Conservation translocations, anthropogenic movements of species to prevent their extinction, have increased substantially over the last few decades. Although multiple species are frequently moved to the same location, current translocation guidelines consider species in isolation. This practice ignores important interspecific interactions and thereby risks translocation failure. We model three different two-species systems to illustrate the inherent complexity of multispecies translocations and to assess the influence of different interaction types (consumer-resource, mutualism, and competition) on translocation strategies. We focus on how these different interaction types influence the optimal founder population sizes for successful translocations and the order in which the species are moved (simultaneous or sequential). Further, we assess the effect of interaction strength in simultaneous translocations and the time delay between translocations when moving two species sequentially. Our results show that translocation decisions need to reflect the type of interaction. While all translocations of interacting species require a minimum founder population size, which is demarked by an extinction boundary, consumer-resource translocations also have a maximum founder population limit. Above the minimum founder size, increasing the number of translocated individuals leads to a substantial increase in the extinction boundary of competitors and consumers, but not of mutualists. Competitive and consumer-resource systems benefit from sequential translocations, but the order of translocations does not change the outcomes for mutualistic interaction partners noticeably. Interspecific interactions are important processes that shape population dynamics and should therefore be incorporated into the quantitative planning of multispecies translocations. Our findings apply whenever interacting species are moved, for example, in reintroductions, conservation introductions, biological

Periods of low precipitation and increasing atmospheric temperature are having adverse effects on tree and forest growth and survival in part via limitations upon photosynthesis. Understanding how different species and plant functional types will physiologically respond to the combination of drought and heat is therefore critical for modeling and predicting the fate of trees and forests under future climate conditions. In addition, climate is changing at a faster pace than the slow natural adjustment rates of most species to their rapidly shifting habitat conditions, especially for long-lived tree species, which poses a major challenge for management, conservation, and preservation strategies and policies. Therefore the current traditional conservation/preservation methods, such as providing migration corridors and increasing suitable habitat at range margins will need to be supplemented with a more direct, innovative, and adaptive approach. One such approach is that of managed migration, which is the intentional translocation of species outside their current habitat in order to reduce anticipated loss of biodiversity caused by climate change related stress. This dissertation addresses these problems through the experimental examination of heat, drought, and the combination of heat and drought on two conifer species that have differing drought tolerances, which can serve as global models for a range of physiological mechanisms to deal with water and heat stress, as well as a social science investigation into the preservation of an iconic conifer tree, the coast redwood into Oregon via managed migration.

With ongoing climate change, many plant species may not be able to adapt rapidly enough, and some conservation experts are therefore considering to translocate warm-adapted ecotypes to mitigate effects of climate warming. Although this strategy, called assisted migration, is intuitively plausible, most of the support comes from models, whereas experimental evidence is so far scarce. Here we present data on multiple ecotypes of six grassland species, which we grew in four common gardens in Germany during a natural heat wave, with temperatures 1.4–2.0°C higher than the long-term means. In each garden we compared the performance of regional ecotypes with plants from a locality with long-term summer temperatures similar to what the plants experienced during the summer heat wave. We found no difference in performance between regional and warm-adapted plants in four of the six species. In two species, regional ecotypes even outperformed warm-adapted plants, despite elevated temperatures, which suggests that translocating warm-adapted ecotypes may not only lack the desired effect of increased performance but may even have negative consequences. Even if adaptation to climate plays a role, other factors involved in local adaptation, such as biotic interactions, may override it. Based on our results, we cannot advocate assisted migration as a universal tool to enhance the performance of local plant populations and communities during climate change.

The conservation and sustainable use of forests in the twenty-first century pose huge challenges for forest management and policy. Society demands that forests provide a wide range of ecosystem services, from timber products, raw materials and renewable energy to sociocultural amenities and habitats for nature conservation. Innovative management and policy approaches need to be developed to meet these often-conflicting demands in a context of environmental change of uncertain magnitude and scale. Genetic diversity is a key component of resilience and adaptability. Overall, forest tree populations are genetically very diverse, conferring them an enormous potential for genetic adaptation via the processes of gene flow and natural selection. Here, we review the main challenges facing our forests in the coming century and focus on how recent progress in genetics can contribute to the development of appropriate practical actions that forest managers and policy makers can adopt to promote forest resilience to climate change. Emerging knowledge will inform and clarify current controversies relating to the choice of appropriate genetic resources for planting, the effect of silvicultural systems and stand tending on adaptive potential and the best ways to harness genetic diversity in breeding and conservation programs. Gaps in our knowledge remain, and we identify where additional information is needed (e.g.;the adaptive value of peripheral populations or the genetic determinism of key adaptive traits) and the types of studies that are required to provide this key understanding. © 2015, Springer-Verlag Berlin Heidelberg.

Serbian spruce (Picea omorika (Pančić) Purk.) is a rare and endangered tertiary relict and endemic species, with restricted and fragmented natural range in Serbia and Bosnia and Herzegovina, mainly around the mid-course of the Drina river. Since the middle of the 19th century, its natural range declines constantly, followed by a decline in the number of mature individuals. The decline of this forest species is slow and mainly attributed to poor regeneration and low competing ability. Given the foreseen worsening of the climate in forthcoming decades, this decline can only accelerate. In recent years, dieback related to drought has been observed as response to extreme weather events suggesting that Serbian spruce will face difficulties in adapting to climate change within its natural range. However, successful use of Serbian spruce in Central and Northern Europe indicates potentially large adaptive potential of this species which, along with the high genetic variability, outweigh the limited morphological variation, self-fertilization, and limitations related to the restricted natural range in the first place, and, indicates possible directions of migration in the second place. In this paper, current conservation actions are discussed, and strategies for the species survival in a changing environment are suggested. Since migration and adaptation are the least likely responses of this species to climate change, measures such as assisted migration may be the only strategy which will enable persistence of Serbian spruce. Current conservation programs, limited to in-situ actions, need to be supplemented with ex-situ actions and strategies. In the worst case scenario, i.e. for species such as Serbian spruce which are unable to migrate and/or adapt to changing climate, the most suitable sites should be identified and colonized in order to prevent extinction in the near future.

Projections of the regional climate model for Southeast Europe generally predict an increasing of temperature and a decrease in precipitation, with some local variations. Higher frequency of extreme weather events and increased flooding can also be expected. This climate change will, among other things, result in changes in habitats and species distribution, and a decrease in biodiversity. In most cases, forest ecosystems will be unable to adapt fast enough to keep pace with changes in climate. Extreme weather events and low precipitation during the growing season will cause high mortality of seedlings after planting. New forests will face the whole range of these changes because of the long lifetime of trees. Reforestation programs must take projections of climate change into consideration. In the long term, new guidelines for site-species matching, provenance selection, and genetic diversity need to be adopted. In the short term, site preparation, planting techniques, and post planting protection need to be improved. In addition, seedling quality (morphological, physiological, and genetic) and planting time need to be specific for each site. New site preparation, planting, and post-planting protection methods are useful tools for short term success measured in seedling survival and initial growth. Seedling quality is essential for short and long term success. Different strategies, such as assisted migration and increased genetic diversity of planting material, can provide better chances for long term success measured in growth, fitness, and capability to produce the next, better adapted generation.

Serbian spruce (Picea omorika (Pančić) Purk.) is a rare and endangered tertiary relict and endemic species, with restricted and fragmented natural range in Serbia and Bosnia and Herzegovina, mainly around the mid-course of the Drina river. Since the middle of the 19th century, its natural range declines constantly, followed by a decline in the number of mature individuals. The decline of this forest species is slow and mainly attributed to poor regeneration and low competing ability. Given the foreseen worsening of the climate in forthcoming decades, this decline can only accelerate. In recent years, dieback related to drought has been observed as response to extreme weather events suggesting that Serbian spruce will face difficulties in adapting to climate change within its natural range. However, successful use of Serbian spruce in Central and Northern Europe indicates potentially large adaptive potential of this species which, along with the high genetic variability, outweigh the limited morphological variation, self-fertilization, and limitations related to the restricted natural range in the first place, and, indicates possible directions of migration in the second place. In this paper, current conservation actions are discussed, and strategies for the species survival in a changing environment are suggested. Since migration and adaptation are the least likely responses of this species to climate change, measures such as assisted migration may be the only strategy which will enable persistence of Serbian spruce. Current conservation programs, limited to in-situ actions, need to be supplemented with ex-situ actions and strategies. In the worst case scenario, i.e. for species such as Serbian spruce which are unable to migrate and/or adapt to changing climate, the most suitable sites should be identified and colonized in order to prevent extinction in the near future.

Serbian spruce (Picea omorika (Pančić) Purk.) is a rare and endangered tertiary relict and endemic species, with restricted and fragmented natural range in Serbia and Bosnia and Herzegovina, mainly around the mid-course of the Drina river. Since the middle of the 19th century, its natural range declines constantly, followed by a decline in the number of mature individuals. The decline of this forest species is slow and mainly attributed to poor regeneration and low competing ability. Given the foreseen worsening of the climate in forthcoming decades, this decline can only accelerate. In recent years, dieback related to drought has been observed as response to extreme weather events suggesting that Serbian spruce will face difficulties in adapting to climate change within its natural range. However, successful use of Serbian spruce in Central and Northern Europe indicates potentially large adaptive potential of this species which, along with the high genetic variability, outweigh the limited morphological variation, self-fertilization, and limitations related to the restricted natural range in the first place, and, indicates possible directions of migration in the second place. In this paper, current conservation actions are discussed, and strategies for the species survival in a changing environment are suggested. Since migration and adaptation are the least likely responses of this species to climate change, measures such as assisted migration may be the only strategy which will enable persistence of Serbian spruce. Current conservation programs, limited to in-situ actions, need to be supplemented with ex-situ actions and strategies. In the worst case scenario, i.e. for species such as Serbian spruce which are unable to migrate and/or adapt to changing climate, the most suitable sites should be identified and colonized in order to prevent extinction in the near future.

Projections of the regional climate model for Southeast Europe generally predict an increasing of temperature and a decrease in precipitation, with some local variations. Higher frequency of extreme weather events and increased flooding can also be expected. This climate change will, among other things, result in changes in habitats and species distribution, and a decrease in biodiversity. In most cases, forest ecosystems will be unable to adapt fast enough to keep pace with changes in climate. Extreme weather events and low precipitation during the growing season will cause high mortality of seedlings after planting. New forests will face the whole range of these changes because of the long lifetime of trees. Reforestation programs must take projections of climate change into consideration. In the long term, new guidelines for site-species matching, provenance selection, and genetic diversity need to be adopted. In the short term, site preparation, planting techniques, and post planting protection need to be improved. In addition, seedling quality (morphological, physiological, and genetic) and planting time need to be specific for each site. New site preparation, planting, and post-planting protection methods are useful tools for short term success measured in seedling survival and initial growth. Seedling quality is essential for short and long term success. Different strategies, such as assisted migration and increased genetic diversity of planting material, can provide better chances for long term success measured in growth, fitness, and capability to produce the next, better adapted generation.

Patterns of adaptive variation within plant species are best studied through common garden experiments, but these are costly and time-consuming, especially for trees that have long generation times. We explored whether genome-wide scanning technology combined with outlier marker detection could be used to detect adaptation to climate and provide an alternative to common garden experiments. As a case study, we sampled nine provenances of the widespread forest tree species, Eucalyptus tricarpa, across an aridity gradient in southeastern Australia. Using a Bayesian analysis we identified a suite of 94 putatively adaptive (outlying) sequence-tagged markers across the genome. Population-level allele frequencies of these outlier markers were strongly correlated with temperature and moisture availability at the site of origin, and with population differences in functional traits measured in two common gardens. Using the output from a canonical analysis of principal coordinates we devised a metric that provides a holistic measure of genomic adaptation to aridity that could be used to guide assisted migration or genetic augmentation.

Patterns of adaptive variation within plant species are best studied through common garden experiments, but these are costly and time-consuming, especially for trees that have long generation times. We explored whether genome-wide scanning technology combined with outlier marker detection could be used to detect adaptation to climate and provide an alternative to common garden experiments. As a case study, we sampled nine provenances of the widespread forest tree species, Eucalyptus tricarpa, across an aridity gradient in southeastern Australia. Using a Bayesian analysis we identified a suite of 94 putatively adaptive (outlying) sequence-tagged markers across the genome. Population-level allele frequencies of these outlier markers were strongly correlated with temperature and moisture availability at the site of origin, and with population differences in functional traits measured in two common gardens. Using the output from a canonical analysis of principal coordinates we devised a metric that provides a holistic measure of genomic adaptation to aridity that could be used to guide assisted migration or genetic augmentation.

Human induced changes in climate, both at local and regional scales alter the conditions for plant establishment. For ecosystem management, it is necessary to quantify the effects of these changes for planning strategies to establish viable plant populations. Survival and growth of provenances of Albizia plurijuga y Ceiba aesculifolia were evaluated in an altitudinal gradient and in two slopes in the city of Morelia, Michoacán, which suffers the effect of the urban heat island. Survival of A. plurijuga varied significantly in response to the altitude above sea level, being lowest at the lowest altitude (34% a 2050 msnm); plant height also varied along the altitudinal gradient. For Ceiba aesculifolia plants there were no significant differences in survival at different altitudes but there were between slopes (northwest 55%, south 27%). The growth variable that showed significant differences was stem diameter, both between slopes (NO = 0,7 cm; S = 0,5 cm) as among altitudes. These results suggest that it is necessary to take into consideration the provenance of tree species when plantations for ecological restoration are planned in areas where climatic conditions have been altered, as is the case if sites under the influence of urban heat islands or the foreseen effects of climate change. In mountain areas, this implies an altitudinal migration uphill., Los cambios generados por el ser humano en el clima, tanto a nivel regional como local, alteran las condiciones en las cuales las plantas pueden establecerse. Para el manejo de ecosistemas es necesario cuantificar los efectos de estos cambios para planear estrategias de establecimiento de poblaciones viables. Se evaluó la supervivencia y crecimiento de familias de Albizia plurijuga y Ceiba aesculifolia en un gradiente altitudinal y en dos laderas en la ciudad de Morelia, Michoacán, que sufre el efecto de isla urbana de calor. La supervivencia de A. plurijuga varió de forma significativa en función de la altitud sobre el nivel del mar, siendo menor a menor altitud (34% a 2050 msnm), y la altura de las plantas también fue diferente en cuanto a la altitud. Para Ceiba aesculifolia no hubo diferencias significativas al finalizar el experimento en cuanto a supervivencia a diferentes altitudes, pero sí entre laderas (noroeste 55%, sur 27%). La variable de crecimiento que mostró diferencias significativas fue el diámetro del tallo tanto entre laderas (NO = 0,7 cm; S = 0,5 cm) como a diferentes altitudes. Los resultados sugieren que se debe considerar el origen de las procedencias de especies arbóreas cuando se desea establecer plantaciones de restauración en sitios en donde las condiciones climáticas han sido alteradas como es el caso de áreas afectadas por el fenómeno de isla urbana de calor o por los efectos esperados por el cambio climático, lo que en zonas montañosas implicaría una transferencia altitudinal hacia arriba.

Human induced changes in climate, both at local and regional scales alter the conditions for plant establishment. For ecosystem management, it is necessary to quantify the effects of these changes for planning strategies to establish viable plant populations. Survival and growth of provenances of Albizia plurijuga y Ceiba aesculifolia were evaluated in an altitudinal gradient and in two slopes in the city of Morelia, Michoacán, which suffers the effect of the urban heat island. Survival of A. plurijuga varied significantly in response to the altitude above sea level, being lowest at the lowest altitude (34% a 2050 msnm); plant height also varied along the altitudinal gradient. For Ceiba aesculifolia plants there were no significant differences in survival at different altitudes but there were between slopes (northwest 55%, south 27%). The growth variable that showed significant differences was stem diameter, both between slopes (NO = 0,7 cm; S = 0,5 cm) as among altitudes. These results suggest that it is necessary to take into consideration the provenance of tree species when plantations for ecological restoration are planned in areas where climatic conditions have been altered, as is the case if sites under the influence of urban heat islands or the foreseen effects of climate change. In mountain areas, this implies an altitudinal migration uphill., Los cambios generados por el ser humano en el clima, tanto a nivel regional como local, alteran las condiciones en las cuales las plantas pueden establecerse. Para el manejo de ecosistemas es necesario cuantificar los efectos de estos cambios para planear estrategias de establecimiento de poblaciones viables. Se evaluó la supervivencia y crecimiento de familias de Albizia plurijuga y Ceiba aesculifolia en un gradiente altitudinal y en dos laderas en la ciudad de Morelia, Michoacán, que sufre el efecto de isla urbana de calor. La supervivencia de A. plurijuga varió de forma significativa en función de la altitud sobre el nivel del mar, siendo menor a menor altitud (34% a 2050 msnm), y la altura de las plantas también fue diferente en cuanto a la altitud. Para Ceiba aesculifolia no hubo diferencias significativas al finalizar el experimento en cuanto a supervivencia a diferentes altitudes, pero sí entre laderas (noroeste 55%, sur 27%). La variable de crecimiento que mostró diferencias significativas fue el diámetro del tallo tanto entre laderas (NO = 0,7 cm; S = 0,5 cm) como a diferentes altitudes. Los resultados sugieren que se debe considerar el origen de las procedencias de especies arbóreas cuando se desea establecer plantaciones de restauración en sitios en donde las condiciones climáticas han sido alteradas como es el caso de áreas afectadas por el fenómeno de isla urbana de calor o por los efectos esperados por el cambio climático, lo que en zonas montañosas implicaría una transferencia altitudinal hacia arriba.

Assisted Colonization (AC) has been proposed as one method of aiding species to adapt to the impacts of climate change. AC is a form of translocation and translocation protocols for threatened species, mostly for reintroduction, are well established in Australia. We evaluate the information available from implementation of translocations to understand how existing policies and guidelines should be varied to plan, review and regulate AC. While the risks associated with AC are potentially greater than those of reintroductions, AC is likely to be the only available method, other than germplasm storage and establishment of captive populations, of conserving many taxa under future climate change. AC may also be necessary to maintain ecosystem services, particularly where keystone species are affected. Current policies and procedures for the preparation of Translocation Proposals will require modification and expansion to deal with Assisted Colonization, particularly in relation to risk management, genetic management, success criteria, moving associated species and community consultation. Further development of risk assessment processes, particularly for invasiveness, and guidelines for genetic management to maintain evolutionary potential are particularly important in the context of changing climate. Success criteria will need to respond to population establishment in the context of new and evolving ecosystems, and to reflect requirements for any co-establishment of interdependent species. Translocation Proposals should always be subjected to independent peer review before being considered by regulators. We conclude that consistent approaches by regulators and multilateral agreements between jurisdictions are required to minimize duplication, to ensure the risk of AC is adequately assessed and to ensure the potential benefits of AC are realized.

Managed relocation (MR) has rapidly emerged as a potential intervention strategy in the toolbox of biodiversity management under climate change. Previous authors have suggested that MR (also referred to as assisted colonization, assisted migration, or assisted translocation) could be a last-alternative option after interrogating a linear decision tree. We argue that numerous interacting and value-laden considerations demand a more inclusive strategy for evaluating MR. The pace of modern climate change demands decision making with imperfect information, and tools that elucidate this uncertainty and integrate scientific information and social values are urgently needed. We present a heuristic tool that incorporates both ecological and social criteria in a multidimensional decision-making framework. For visualization purposes, we collapse these criteria into 4 classes that can be depicted in graphical 2-D space. This framework offers a pragmatic approach for summarizing key dimensions of MR: capturing uncertainty in the evaluation criteria, creating transparency in the evaluation process, and recognizing the inherent tradeoffs that different stakeholders bring to evaluation of MR and its alternatives.

Steane D.A., Potts B.M., McLean E., Prober S.M., Stock W.D., Vaillancourt R.E., & Byrne M. (2014). Genome-wide scans detect adaptation to aridity in a widespread forest tree species. Molecular Ecology, 23(10), 2500-2513. Available here