TY - THES T1 - Getting to the Root of Change: How Plants Respont to Novel Climates, Soils, and Soil Biota T2 - Forestry Y1 - 2019 A1 - Michael J. Remke ED - Matthew Bowker ED - Nancy Johnson ED - Catherine Gehring ED - Thomas Kolb KW - arbuscular mycorrhizal KW - climate change KW - ecto-mycorrhizal KW - Plants KW - soil biota KW - soils AB -

Global climate change is having profound and widespread effects on plant growth and survival. For the southwestern United States, warmer temperatures, more variable precipitation and more extreme droughts are expected. As plant populations experience these changes they may adapt and persist in place or may experience increasing environmental stress, eventually leading to mortality. An interesting component of environmental change is that different edaphic conditions may mitigate or exacerbate changes in the environment. As an example, coarse soils with low water holding capacity may exacerbate a change in water availability. Additionally, soil biota may play a critical role in facilitating plant survival during environmental change. Mycorrhizal fungi and plant growth promoting rhizobacteria both have been shown to have an impact on plant water uptake and physiological regulation. Interestingly, plants migrating to new locations maybe experiencing different novel environments by migrating across edaphic boundaries. Novel edaphic environments may have vastly different physical and chemical properties to which plant populations are adapted to. Furthermore, plant migration often occurs independently of the migration of associated soil microbes, including mycorrhizal fungi. Both arbuscular mycorrhizal (AM) fungi and ecto-mycorrhizal (EM) fungi play important roles in plant nutrient and water uptake. While plant responses to changes in climate, or even soils are fairly well understood, few studies have examined the impact of simultaneous change in climate, soil, and soil biota on plant performance To better understand adaptation to novel environments, the grass Bouteloua gracilis was grown at six field sites: two natal source sites, a +2°C site, a +3°C site, a -2°C site and -3°C site where the warmer sites simulate in situ warming and precipitation changes whereas the cooler sites simulate plant migration. In these papers we define home as soil communities from the plants site of origin, and away as soil communities from the transplant site. Plants at all of the transplant sites were then grown in the following combinations of soil and soil biota: 1) home soil, home soil biota, 2) away soil, home soil biota, 3) home soil, away soil biota and 4) away soil, away soil biota. Home refers to soil or soil biota from the same site as the plant, whereas away represents soil or soil biota from the transplant site. We found plants generally grew more in cooler/wetter environments than in warm/dry environments. In warm/dry environments, we also found that home soil biota generally facilitated plant growth and plants were larger than those grown with away soil biota. Away soils originating from one site in particular, had a dramatic negative effect on plant growth. In general, our results demonstrate that warmer temperatures have a negative effect on plant growth that can be mitigated partly by plant associated soil biota. In order to better understand plant physiological responses to changes in environment, we conducted a similar, parallel study with the tree Pinus ponderosa where we grew P. ponderosa at three field sites: one natal source site, a +2°C site and a -2°C site. We used the same treatment combinations described above. We monitored plant growth and leaf physiology metrics during the monsoon season. Trees grown at the +2°C site grew as large as those grown at the home site when they had their home soil biota, but not when they had their away soil biota. Trees with their home soil biota maintained nearly 2× the maximum net photosynthetic rate and stomatal conductance rate than those grown with their away soil biota. These results imply that home soil biota play a critical role in either water uptake or physiological regulation and away soil biota do not have the same effect. Lastly, we conducted a third experiment to more closely examine how the plant symbiosis with home soil biota influence plant growth differs from that with away soil biota. In this experiment, we grew the grass Bouteloua gracilis from a relatively wet and relatively dry site with either home or away soil biota. We then subjected plants to a watering regime that simulated or moderate drying or extreme drying and monitored plant growth. At the termination of the experiment we recorded fungal structures colonizing plant roots. We observed that home plant-soil biota combinations grew larger and had a greater portion of roots colonized by AM fungi structures for nutrient exchange and uptake (hyphae and arbuscules). In contrast, away plant-soil biota combinations resulted in a greater portion of roots colonized by less beneficial AM fungi structures that are used for fungal carbon storage (vesicles). These results may indicate that home plant-fungal pairings generally have greater mutualistic function, partially due to fungal allocation. Plants responding to changes in their environment will be exposed to a wide array of scenarios and thus exhibit a wide range of responses. In general, our studies indicate that soil biota mitigate some of the negative effects of warmer drier environments on plant growth. We also demonstrate that plants migrating to novel cooler and wetter environments are much less dependent on these soil biota, however, edaphic boundaries are likely to be a barrier to plant growth with certain soil environments a greater barrier than others.

JF - Forestry PB - Northern Arizona University CY - Flagstaff, Arizona, USA VL - Doctor of Philosophy in Forest Science UR - https://www.sega.nau.edu/sites/default/files/Getting_to_the_Root_of_Change.pdf ER - TY - JOUR T1 - Southwestern white pine (Pinus strobiformis) species distribution models project a large range shift and contraction due to regional climatic changes JF - Forest Ecology and Managment Y1 - 2018 A1 - Andrew J. Shirk A1 - Samuel A. Cushman A1 - Kristen M. Waring A1 - Christian A. Wehenkel A1 - Alejandro Leal-Sáenz A1 - Chris Toney A1 - Carlos A. Lopez-Sanchez KW - climate change KW - Multi-scale KW - Pinus strobiformis KW - Range shift KW - Southwestern white pine KW - Species distribution model AB -

Southwestern white pine (Pinus strobiformis; SWWP) is a conifer species that occurs at mid to high elevations in
the mountains of Arizona, New Mexico, and northern Mexico. A key component of mixed conifer forests in the
region, SWWP is an important species for wildlife and biodiversity. The dual threats of the non-native fungal
pathogen that causes white pine blister rust (WPBR) and a warmer, drier projected future climate have created
an uncertain future for SWWP. In this study, we used a novel multi-scale optimization approach including an
ensemble of four species distribution modeling methods to explore the relationship between SWWP occurrence
and environmental variables based on climate, soil, and topography. Spatial projections of these models reflecting
the present climate provide an improved range map for this species that can be used to guide field data
collection and monitoring of WPBR outbreaks. Future projections based on two emissions scenarios and an
ensemble of 15 general circulation models project a large range shift and range contraction by 2080. Changes in
the future distribution were particularly extreme under the higher emissions scenario, with a more than 1000 km
northerly shift in the mean latitude and 500m increase in the mean elevation of the species’ suitable habitat.
This coincided with a range contraction of over 60% and a significant increase in habitat fragmentation. The
ability of SWWP to realize its projected future range will depend on colonization at the leading edge of the range
shift, including dispersal dynamics, resistance to WPBR, competition with other species, and genetic adaptations
to local climate. Our results provide information that can be used to guide monitoring efforts and inform conservation
planning for this keystone species.

VL - 411:176-186 UR - https://doi.org/10.1016/j.foreco.2018.01.025 ER - TY - JOUR T1 - Species Introductions and Their Cascading Impacts on Biotic Interactions in desert riparian ecosystems. JF - Integrative and comparative biology Y1 - 2015 A1 - Hultine,Kevin R A1 - Bean,Dan W A1 - Dudley,Tom L A1 - Gehring,Catherine A KW - Animals KW - climate change KW - Desert Climate KW - Ecosystem KW - Introduced Species KW - Rivers AB -

Desert riparian ecosystems of North America are hotspots of biodiversity that support many sensitive species, and are in a region experiencing some of the highest rates of climatic alteration in North America. Fremont cottonwood, Populus fremontii, is a foundation tree species of this critical habitat, but it is threatened by global warming and regional drying, and by a non-native tree/shrub, Tamarix spp., all of which can disrupt the mutualism between P. fremontii and its beneficial mycorrhizal fungal communities. Specialist herbivorous leaf beetles (Diorhabda spp.) introduced for biocontrol of Tamarix are altering the relationship between this shrub and its environment. Repeated episodic feeding on Tamarix foliage by Diorhabda results in varying rates of dieback and mortality, depending on genetic variation in allocation of resources, growing conditions, and phenological synchrony between herbivore and host plant. In this article, we review the complex interaction between climatic change and species introductions and their combined impacts on P. fremontii and their associated communities. We anticipate that (1) certain genotypes of P. fremontii will respond more favorably to the presence of Tamarix and to climatic change due to varying selection pressures to cope with competition and stress; (2) the ongoing evolution of Diorhabda's life cycle timing will continue to facilitate its expansion in North America, and will over time enhance herbivore impact to Tamarix; (3) defoliation by Diorhabda will reduce the negative impact of Tamarix on P. fremontii associations with mycorrhizal fungi; and (4) spatial variability in climate and climatic change will modify the capacity for Tamarix to survive episodic defoliation by Diorhabda, thereby altering the relationship between Tamarix and P. fremontii, and its associated mycorrhizal fungal communities. Given the complex biotic/abiotic interactions outlined in this review, conservation biologists and riparian ecosystem managers should strive to identify and conserve the phenotypic traits that underpin tolerance and resistance to stressors such as climate change and species invasion. Such efforts will greatly enhance conservation restoration efficacy for protecting P. fremontii forests and their associated communities.

VL - 55 SN - 1540-7063 UR - http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&DbFrom=pubmed&Cmd=Link&LinkName=pubmed_pubmed&LinkReadableName=Related%20Articles&IdsFromResult=25908667&ordinalpos=3&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSumhttp://www.ncbi. IS - 4 ER - TY - JOUR T1 - Genes to ecosystems: exploring the frontiers of ecology with one of the smallest biological units. JF - The New phytologist Y1 - 2011 A1 - Wymore,Adam S A1 - Keeley,Annika T H A1 - Yturralde,Kasey M A1 - Schroer,Melanie L A1 - Propper,Catherine R A1 - Whitham,Thomas G KW - Animals KW - Cell Respiration KW - climate change KW - Ecosystem KW - Environmental Pollution KW - Female KW - Fishes KW - Gene Expression KW - Haplotypes KW - Humans KW - Introduced Species KW - Male KW - Plants KW - Population Dynamics KW - Sciuridae AB -

Genes and their expression levels in individual species can structure whole communities and affect ecosystem processes. Although much has been written about community and ecosystem phenotypes with a few model systems, such as poplar and goldenrod, here we explore the potential application of a community genetics approach with systems involving invasive species, climate change and pollution. We argue that community genetics can reveal patterns and processes that otherwise might remain undetected. To further facilitate the community genetics or genes-to-ecosystem concept, we propose four community genetics postulates that allow for the conclusion of a causal relationship between the gene and its effect on the ecosystem. Although most current studies do not satisfy these criteria completely, several come close and, in so doing, begin to provide a genetic-based understanding of communities and ecosystems, as well as a sound basis for conservation and management practices.

VL - 191 SN - 0028-646X UR - http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&DbFrom=pubmed&Cmd=Link&LinkName=pubmed_pubmed&LinkReadableName=Related%20Articles&IdsFromResult=21631507&ordinalpos=3&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSumhttp://www.ncbi. IS - 1 ER -