Post-fire germination and plant invasion in Mediterranean Chile.

Premise: Plants from regions where fire is a novel disturbance typically lack fire-adaptive traits, which may explain the post-fire invasion by alien plants from fire-prone ecosystems. Unlike many Mediterranean-type ecosystems, the Chilean matorral has a limited evolutionary history with fire. We predict that a negative germination response to fire will be more frequent in its native flora than in alien plants, most of which originate from the fire-prone Mediterranean Basin.

Exploring the Uniqueness of Photosynthetic and Hydraulic Traits of Antarctic Vascular Plants: A Comparative Study with Related Species.

Deschampsia antarctica and Colobanthus quitensis are extremophile species thriving from the Andes to the Subantarctic regions. Although they share this gradient with other species, notably, they are the only flowering plants growing naturally in Antarctica. These species exhibit traits typical of xeromorphy, such as high leaf mass area (LMA) and leaf density (LD), which influence mesophyll conductance and photosynthesis.

Hydraulic and Photosynthetic Performance of Antarctic Plants Under Successive Freeze-Thaw Cycles.

Climate change projections predict warming and increased weather variability, mainly in polar regions, altering freeze-thaw patterns. However, the effects of rising temperatures and more frequent freeze-thaw events on the water and CO management of Antarctic plants remain unclear. To address this, we conducted a laboratory experiment to investigate how growth temperature (5°C and 15°C) and successive freeze-thaw cycles influence the hydraulic and photosynthetic performance of Deschampsia antarctica (D.

Morpho-Physiological Traits and Dehydration Tolerance of High-Altitude Andean Wetland Vegetation in the Chilean Atacama Region.

High-altitude wetlands of the Andes (HAWA) are unique ecosystems influenced by substrate conditions and reliant on consistent water supply from precipitation, runoff, groundwater, and glacial melting. Considering the diverse ecosystem services provided by HAWAs and the increasing threat these ecosystems face from natural and anthropogenic factors, such as drought, land-use change, and climate change, it is crucial to conduct a comprehensive assessment of their vulnerability. In this study, we characterized the functional trait spectrum of dominant plant species within the Salar de Pedernales, Quebrada Leoncito (Leoncito) and Río Negro HAWAs and explored the relationships between these traits and key environmental variables.

Ecophysiology of Antarctic Vascular Plants: An Update on the Extreme Environment Resistance Mechanisms and Their Importance in Facing Climate Change.

Antarctic flowering plants have become enigmatic because of their unique capability to colonize Antarctica. It has been shown that there is not a single trait that makes and so special, but rather a set of morphophysiological traits that coordinately confer resistance to one of the harshest environments on the Earth. However, both their capacity to inhabit Antarctica and their uniqueness remain not fully explained from a biological point of view.

Ecological and metabolic implications of the nurse effect of Maihueniopsis camachoi in the Atacama Desert.

Plant-plant positive interactions are key drivers of community structure. Yet, the underlying molecular mechanisms of facilitation processes remain unexplored. We investigated the 'nursing' effect of Maihueniopsis camachoi, a cactus that thrives in the Atacama Desert between c.

Trait evolution during a rapid global weed invasion despite little genetic differentiation.

Invasive species often possess a great capacity to adapt to novel environments in the form of spatial trait variation, as a result of varying selection regimes, genetic drift, or plasticity. We explored the geographic differentiation in several phenotypic traits related to plant growth, reproduction, and defense in the highly invasive by measuring neutral genetic differentiation ( ), and comparing it with phenotypic differentiation ( ), in a common garden experiment in individuals originating from regions representing the species distribution across five continents. Native plants were more fecund than non-native plants, but the latter displayed considerably larger seed mass.

Testing the stress gradient hypothesis in soil bacterial communities associated with vegetation belts in the Andean Atacama Desert.

Background: Soil microorganisms are in constant interaction with plants, and these interactions shape the composition of soil bacterial communities by modifying their environment. However, little is known about the relationship between microorganisms and native plants present in extreme environments that are not affected by human intervention. Using high-throughput sequencing in combination with random forest and co-occurrence network analyses, we compared soil bacterial communities inhabiting the rhizosphere surrounding soil (RSS) and the corresponding bulk soil (BS) of 21 native plant species organized into three vegetation belts along the altitudinal gradient (2400-4500 m a.

Nutrient availability regulates Deschampsia antarctica photosynthetic and stress tolerance performance in Antarctica.

Deschampsia antarctica is one of the only two native vascular plants in Antarctica, mostly located in the ice-free areas of the Peninsula's coast and adjacent islands. This region is characterized by a short growing season, frequent extreme climatic events, and soils with reduced nutrient availability. However, it is unknown whether its photosynthetic and stress tolerance mechanisms are affected by the availability of nutrients to deal with this particular environment.

The Upper Range Limit of Alien Plants Is Not in Equilibrium with Climate in the Andes of Central Chile.

Alien plant species are colonizing high-elevation areas along roadsides. In this study, we evaluated whether the distributions of alien plants in the central Chilean mountains have reached climatic equilibrium (i.e.

Vegetation drives the response of the active fraction of the rhizosphere microbial communities to soil warming in Antarctic vascular plants.

In the Antarctic Peninsula, increases in mean annual temperature are associated with the coverage and population density of the two Antarctic vascular plant species-Deschampsia antarctica and Colobanthus quitensis-potentially modifying critical soil processes. In this study, we characterized the diversity and community composition of active microorganisms inhabiting the vascular plant rhizosphere in two sites with contrasting vegetation cover in King George Island, Western Antarctic Peninsula. We assessed the interplay between soil physicochemical properties and microbial diversity and composition, evaluating the effect of an in situ experimental warming on the microbial communities of the rhizosphere from D.

Respiratory and Photosynthetic Responses of Antarctic Vascular Plants Are Differentially Affected by CO Enrichment and Nocturnal Warming.

Projected rises in atmospheric CO concentration and minimum night-time temperatures may have important effects on plant carbon metabolism altering the carbon balance of the only two vascular plant species in the Antarctic Peninsula. We assessed the effect of nocturnal warming (8/5 °C vs. 8/8 °C day/night) and CO concentrations (400 ppm and 750 ppm) on gas exchange, non-structural carbohydrates, two respiratory-related enzymes, and mitochondrial size and number in two species of vascular plants.

Anatomical and biochemical evolutionary ancient traits of Araucaria araucana (Molina) K. Koch and their effects on carbon assimilation.

The study of ancient species provides valuable information concerning the evolution of specific adaptations to past and current environmental conditions. Araucaria araucana (Molina) K. Koch belongs to one of the oldest families of conifers in the world, but despite this, there are few studies focused on its physiology and responses to changes in environmental conditions.

Net plant interactions are highly variable and weakly dependent on climate at the global scale.

Although plant-plant interactions (i.e. competition and facilitation) have long been recognised as key drivers of plant community composition and dynamics, their global patterns and relationships with climate have remained unclear.

Invasive Stages within Alien Species and Hutchinson's Duality: An Example Using Invasive Plants of the Family Fabaceae in Central Chile.

To understand the factors that limit invasive expansion in alien species, it is critical to predict potential zones of colonization. Climatic niche can be an important way to predict the potential distribution of alien species. This correlation between niche and geographic distribution is called Hutchinson's duality.

Network motifs involving both competition and facilitation predict biodiversity in alpine plant communities.

Biological diversity depends on multiple, cooccurring ecological interactions. However, most studies focus on one interaction type at a time, leaving community ecologists unsure of how positive and negative associations among species combine to influence biodiversity patterns. Using surveys of plant populations in alpine communities worldwide, we explore patterns of positive and negative associations among triads of species (modules) and their relationship to local biodiversity.

Carbon allocation to growth and storage depends on elevation provenance in an herbaceous alpine plant of Mediterranean climate.

It is unclear whether the frequently observed increase in non-structural carbohydrates (NSC) in plants exposed to low temperatures or drought reflects a higher sensitivity of growth than photosynthesis in such conditions (i.e. sink limitation), or a prioritization of carbon (C) allocation to storage.

Going off trails: How dispersed visitor use affects alpine vegetation.

Mountain protected areas provide a range of ecosystem services including conserving biodiversity, while often providing recreation and tourism opportunities. Unfortunately, tourists and pack animals used to transport equipment can damage sensitive alpine vegetation particularly when they leave trails. This study assessed the impacts of disturbance from off trail use on alpine vegetation in a popular park in the Andes.

Assessing the ecophysiological response of a mountain grassland community to ski slope management through isotopic composition.

A scarce natural snow cover forces an increasing use of artificial snow on ski slopes and returns a small amount of snowmelt water available to plants outside the pistes at the beginning of the growing season. We tested if the use of artificial snow on the ski slopes and the decreased natural snow cover outside the ski slopes lead to changes in the leaf ecophysiology of dominant species in a ski area located in Northern Italy. Using carbon (C/C) and oxygen (O/O) stable isotope ratios in plant leaves, we estimated the intrinsic water use efficiency (iWUE) and we speculated about changes in photosynthesis and stomatal conductance.

Low-temperature tolerance of the Antarctic species Deschampsia antarctica: A complex metabolic response associated with nutrient remobilization.

The species Deschampsia antarctica (DA) is one of the only two native vascular species that live in Antarctica. We performed ecophysiological, biochemical, and metabolomic studies to investigate the responses of DA to low temperature. In parallel, we assessed the responses in a non-Antarctic reference species (Triticum aestivum [TA]) from the same family (Poaceae).

How do vascular plants perform photosynthesis in extreme environments? An integrative ecophysiological and biochemical story.

In this work, we review the physiological and molecular mechanisms that allow vascular plants to perform photosynthesis in extreme environments, such as deserts, polar and alpine ecosystems. Specifically, we discuss the morpho/anatomical, photochemical and metabolic adaptive processes that enable a positive carbon balance in photosynthetic tissues under extreme temperatures and/or severe water-limiting conditions in C species. Nevertheless, only a few studies have described the in situ functioning of photoprotection in plants from extreme environments, given the intrinsic difficulties of fieldwork in remote places.