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Germination kickstarts plant recruitment. Hence, acknowledging this process is a prerequisite for restoration of ecosystems. In dry forests, where opportunities for plant establishment occur in a narrow window of opportunity, seeds must respond to cues to germinate when conditions for growth are suitable. Understanding the strategies and adaptations of seeds to the seasonal dry-forest ecosystems is needed to guide restoration and management actions in the face of climate change. We investigated the effects of scarification, temperature and light in germination percentage, germination time and synchrony of six woody Fabaceae species. The species have ecological potential for restoration and are of cultural and economic importance for the local people in the Tehuacán-Cuicatlán Valley, Mexico. We carried out a multifactorial germination experiment with five temperatures, two light regimes and two scarification conditions for Mimosa luisana, M. polyantha, M. adenantheroides, M. lactiflua, Acaciella angustissima and Vachellia constricta. Responses differed among the species, but they all germinated in a wide range of temperatures (10°C to 40°C). Mechanical scarification highly increased the germination percentage of all species. Higher temperature increased and speeded up germination in dark conditions for most of the species. We found more heterogeneous responses in germination synchrony among species. Despite that the studied species had high germination percentages in warm temperatures, their recruitment in nature might be negatively affected by warmer and drier conditions, and by the loss of shade and seed dispersers due to deforestation and changes in land use. It is crucial to study not just germination percentage and time but also other aspects of the germination process such as the germination synchrony, since it might reveal useful information for management actions.

Rapid climate change imperils a multitude of species, demanding either swift adaptation or a strategic migration to new areas to safeguard their existence. Species confined to spatially limited habitats face heightened vulnerability as ecological conditions may undergo dramatic shifts across their range. In this study, we delve into the processes shaping the geographic distribution of Mimosa luisana, a species endemic to the Tehuacán-Cuicatlán Valley in Mexico, having high potential for use in ecological restoration. We aimed to forecast the response of M. luisana to climate change and to formulate strategic management guidelines in the face of global change. We conducted a reciprocal translocation and a common garden experiment with three provenances of M. luisana. We used populations originating from the lower, central and upper range-limit of the altitudinal and latitudinal distribution of the species. We found significant differences in the relative growth rate, leaf biomass change and specific leaf area among the three provenances during their early establishment, but found little evidence of local adaptation among the studied populations. Instead, all provenances did best at the central part of the species range. We suggest that cold temperatures might be delimiting the upper limit of M. luisana within the Tehuacán-Cuicatlán Valley, whereas tolerance to drought may set lower limits. M. luisana might respond to climate change not by upward shifts of each locally adapted population distributed along the elevational gradient, but by conditions improving at the high-elevation edge in response to warming. A management implication from our results is that ensuring genetic diversity of the seed batches may be more important than only using local seed sources of M. luisana in ecological restoration actions.

Climate change is threatening range-restricted species world-wide, but assessments of vulnerability is lacking in many areas, especially in tropical mountain regions. We assessed the vulnerability of the tropical dry forest species Mimosa luisana, an important nurse plant facilitating the establishment of other species, and provider of ecosystem services to local communities. We projected changes in the geographic distribution and extent of the climatic envelope of M. luisana for the periods 2021-2040, 2041-2060, 2061-2080, using the Maximun Entropy species distribution model (MaxEnt). We also tested the response of local provenances of M. luisana to different climate change scenarios by transplanting them to new elevations. 

We found that new areas at higher elevation will become climatically suitable for M. luisana in the future, without losing its current geographic range, so that its geographic range may expand by between 50% and 313%. Transplantation showed that M. luisana can grow and survive in a wide range of conditions. Moreover, M. luisana was able to survive when translocated 700 m upwards, to areas above its current elevational limit. 

We conclude that M. luisana is not in need of assisted migration to escape climate-related extinction, but translocation to areas that become climatically suitable may be beneficial to its conservation. The species may be used in ecological restoration projects in a wide range of conditions, including beyond its present range, increasing the likelihood of success in present and future ecological restoration actions. However, we acknowledge the need for assessing the climate-change effects on reproduction and the dispersal capacity of the species. 

The arid and semi-arid vegetation zones of the world often harbour high species diversity and significant endemism. They also face elevated levels of environmental pressures due to high human settlement densities and weak institutional systems. This necessitates adequate conservation and ecological restoration efforts, which in turn demand physiological and ecological knowledge of the species involved. Seed traits can be important for plant establishment success and growth, especially at early life stages, when seedlings also are most sensitive. We studied the role of seed traits for early establishment of the woody Fabaceae species Mimosa luisana, a candidate species for use in ecological restoration within the Tehuacán-Cuicatlán Valley (TCV), Mexico. We assessed the relationship between seed traits and biomass production, biomass allocation and relative growth rate (RGR) up to 200 days after germination, in a common garden experiment using three populations that represented the lower, central and upper limit of M. luisana geographical distribution. M. luisana seeds were 1.9-3.9 mm long, 1.7-3.3 mm wide, 1.2-2.9 mm thick, and weighed from 3 to 19 mg. We found the seeds from the lower limit to be lighter, thinner and less spherical than the central and upper populations. Across all populations, 41% of the total biomass consisted of leaves, followed by shoots (33%) and roots (27%). The biomass production and allocation showed no significant difference among populations during the initial harvests; however, discernible differences emerged over time. Seed weight initially had a significant effect on biomass production, but this effect was lost with time. Seed weight alone explained only 0.82% of the total variance of biomass production, while harvest age explained 40.05%, and seed provenance 3.08%. The correlation between seed weight and RGR was slightly negative but not significant. These results have implications for efforts to ecologically restore dry forests in the region as well as how to implement climate change adaptation and conservation translocation actions, as these might imply sowing and establishing M. luisana at new sites. Given the small variance in biomass accumulation explained by seed traits and provenance, efforts to protect M. luisana during germination and establishment are likely to be more important for management success than the seed source used.