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Populus fremontii (Fremont cottonwood) is recognized as one of the most important foundation tree species in the southwestern USA and northern Mexico because of its ability to structure communities across multiple trophic levels, drive ecosystem processes and influence biodiversity via genetic-based functional trait variation. However, the areal extent of P. fremontii cover has declined dramatically over the last century due to the effects of surface water diversions, non-native species invasions and more recently climate change. Consequently, P. fremontii gallery forests are considered amongst the most threatened forest types in North America. In this paper, we unify four conceptual areas of genes to ecosystems research related to P. fremontii's capacity to survive or even thrive under current and future environmental conditions: (i) hydraulic function related to canopy thermal regulation during heat waves; (ii) mycorrhizal mutualists in relation to resiliency to climate change and invasion by the non-native tree/shrub, Tamarix ; (iii) phenotypic plasticity as a mechanism for coping with rapid changes in climate; and (iv) hybridization between P. fremontii and other closely related Populus species where enhanced vigour of hybrids may preserve the foundational capacity of Populus in the face of environmental change. We also discuss opportunities to scale these conceptual areas from genes to the ecosystem level via remote sensing. We anticipate that the exploration of these conceptual areas of research will facilitate solutions to climate change with a foundation species that is recognized as being critically important for biodiversity conservation and could serve as a model for adaptive management of arid regions in the southwestern USA and around the world. [ABSTRACT FROM AUTHOR]

Climate change and competition from invasive species remain two important challenges in restoration. We examined the hypothesis that non‐native tamarisk (Tamarix spp.) reestablishment after aboveground removal is affected by genetics‐based architecture of native Fremont cottonwood (Populus fremontii) used in restoration. As cottonwood architecture (height, canopy width, number of stems, and trunk diameter) is, in part, determined by genetics, we predicted that trees from different provenances would exhibit different architecture, and mean annual maximum temperature transfer distance from the provenances would interact with the architecture to affect tamarisk. In a common garden in Chevelon, AZ, U.S.A. (elevation 1,496 m), with cottonwoods from provenances spanning its elevation distribution, we measured the performance of both cottonwoods and tamarisk. Several key findings emerged. On average, cottonwoods from higher elevations were (1) two times taller and wider, covered approximately 3.5 times more basal area, and were less shrubby in appearance, by exhibiting four times fewer number of stems than cottonwoods from lower elevations; (2) had 50% fewer tamarisk growing underneath, which were two times shorter and covered 6.5 times less basal area than tamarisk growing underneath cottonwoods of smaller stature; and (3) the number of cottonwood stems did not affect tamarisk growth, possibly because the negative relationship between cottonwood stems and basal area. In combination, these findings argue that cottonwood architecture is affected by local conditions that interact with genetics‐based architecture. These interactions can negatively affect the growth of reinvading tamarisk and enhance restoration success. Our study emphasizes the importance of incorporating genetic and environmental interactions of plants used in restoration. [ABSTRACT FROM AUTHOR]

Discussion around anthropogenic climate change has occurred for over 100 years. However, in recent decades, these discussions have intensified due to increased confidence in scientific research highlighting adverse effects, increased knowledge breadth in climate science, and heightened public and political awareness and engagement on the topic. Climate change is now acknowledged as one of the biggest challenges and threats to modern lifestyles. Nature-based solutions (NBS), as a mediator and mitigator to adverse climate change effects, is an emerging area of expanding research collateral and practitioner literacy. To highlight current NBS knowledge, existing knowledge gaps, and research trends, a Quantitative Systematic Literature Review (QSLR) was undertaken (n = 54). This QSLR reveals the short temporal span of articles relating to NBS as a response to climate change, with most articles being of a research style format. NBS research focus areas were found to be dominated by ecological and infrastructure approaches to climate change mitigation, and ecological and technical positions were found to be most topical across the current climate change literature. Multiple knowledge gaps were identified by the review, namely the lack of broader conceptual approaches and knowledge acquisition regarding climate change responses via NBS, as well as the psychological relationship humans share with NBS and climate change, adverse or otherwise. These knowledge gaps highlight where future research inquiry may be directed to increase the value and completion of this research area. It is hoped that this QSLR will assist in increasing the profile of NBS in the multidisciplinary and complex response to anthropogenic climate change, as well as contribute to the growth in investment and implementation of NBS assets for a rigid and resilient global future. [ABSTRACT FROM AUTHOR]