Caroline A. Havrilla

Colorado State University | CSU · Department of Forest and Rangeland Stewardship

Understanding the importance of biotic interactions in driving the distribution and abundance of species is a central goal of plant ecology. Early vascular plants likely colonized land occupied by biocrusts — photoautotrophic, surface‐dwelling soil communities comprised of cyanobacteria, bryophytes, lichens and fungi — suggesting biotic interaction...

Drylands are Earth's largest terrestrial biome and support one‐third of the global population. However, they are also highly vulnerable to land degradation. Despite widespread demand for dryland restoration and rehabilitation, little information is available to help land managers effectively re‐establish native perennial vegetation across drylands....

Biological soil crusts (biocrusts) occur in drylands globally where they support ecosystem functioning by increasing soil stability, reducing dust emissions and modifying soil resource availability (e.g. water, nutrients). Determining biocrust condition and extent across landscapes continues to present considerable challenges to scientists and land...

Soil degradation is one of the greatest environmental issues our planet faces today, with over 33% of Earth's soils currently degraded. Drylands are especially vulnerable to soil degradation given their history of intensive land use and desertification. Active soil restoration has been identified as a leading strategy to combat soil degradation and...

The capture and use of water are critically important in drylands, which collectively constitute Earth's largest biome. Drylands will likely experience lower and more unreliable rainfall as climatic conditions change over the next century. Dryland soils support a rich community of microphytic organisms (biocrusts), which are critically important be...

National-level governments are directing and funding climate adaptation research, which is essential to informing effective and equitable adaptation practices. We sought to understand how United States (US) federal agencies prioritize, direct, and fund research related to climate adaptation and climate resilience through analyzing climate action pl...

Up to 35% of global drylands have experienced degradation due to anthropogenic impacts, including physical disturbances like trampling and soil removal. These physical disturbances can result in the loss of soil communities known as biological soil crusts (biocrusts) and the important functions they provide, such as soil stability and fertility. Th...

Restoration in dryland ecosystems often has poor success due to low and variable water availability, degraded soil conditions, and slow plant community recovery rates. Restoration treatments can mitigate these constraints but, because treatments and subsequent monitoring are typically limited in space and time, our understanding of their applicabil...

Aim Grasslands cover a third of Earth's landmass and provide critical ecosystem services. Anticipating how perennial C3 (cool‐season) and C4 (warm‐season) grasses respond to climate change will be key to predicting future composition and functioning of grasslands. Here, we evaluate environmental drivers of C3 and C4 perennial distributions and asse...

Studies of biological soil crusts (biocrusts) have proliferated over the last few decades. The biocrust literature has broadened, with more studies assessing and describing the function of a variety of biocrust communities in a broad range of biomes and habitats and across a large spectrum of disciplines, and also by the incorporation of biocrusts...

The match between species trait values and local abiotic filters can restrict community membership. An often‐implicit assumption of this relationship is that abiotic filters select for a single locally optimal strategy, though difficulty in isolating effects of the abiotic environment from those of dispersal limitation and biotic interactions has r...

Non‐forest ecosystems, dominated by shrubs, grasses and herbaceous plants, provide ecosystem services including carbon sequestration and forage for grazing, and are highly sensitive to climatic changes. Yet these ecosystems are poorly represented in remotely sensed biomass products and are undersampled by in situ monitoring. Current global change t...

Characterizing variation in plant functional traits is often key to understanding community‐level processes and predicting ecosystem responses to environmental change. Trait‐based ecology has focused on interspecific trait variation, but sources and consequences of within‐species ontogenetic trait variation, particularly during early stages of deve...

Litter crusts in dryland ecosystems can promote ecosystem functioning through modification of the soil microhabitat. Yet, we still have a limited understanding of how soil microbial communities associated with litter crusts may contribute to soil functioning. Therefore, we examined the changes of soil organic carbon, soil total nitrogen, soil ammon...

Plant litter is most important in mediating the soil functioning of ecosystem recovery. In sandy ecosystems, the formation of plant litter crust plays crucial roles in the process of restoration. This research disentangled the influence of the plant litter crust on sandy soil properties and the bacterial community, and the effect of the bacterial t...

Plant litter is most important in mediating soil functioning during ecosystem recovery. In sandy ecosystems, the formation of a plant litter crust plays a crucial role in the process of restoration. This research explored the influence of the plant litter crust on sandy soil properties and the bacterial community, and the effect of the bacterial ta...

Biological soil crusts (biocrusts) are a complex community of algae, cyanobacteria, lichens, bryophytes, and assorted bacteria, fungi, archaea, and bacteriophages that colonize the soil surface. Biocrusts are particularly common in drylands and are found in arid and semiarid ecosystems worldwide. While diminutive in size, biocrusts often cover larg...

Grasslands cover an estimated 31%–43% of the Earth’s land surface, possess an intrinsic conservation value, and offer indispensable ecosystem services. However, grasslands have been extensively managed and exploited, face major threats, including land-use change, climate change, woody encroachment, and biological invasion. The primary tools used to...

Non-forest ecosystems, dominated by shrubs, grasses and herbaceous plants, provide ecosystem services including carbon sequestration and forage for grazing, yet are highly sensitive to climatic changes. Yet these ecosystems are poorly represented in remotely-sensed biomass products and are undersampled by in-situ monitoring. Current global change t...

Drylands are Earth’s largest terrestrial biome and support one third of the global population. However, they are also highly vulnerable to land degradation. Despite widespread demand for dryland restoration and rehabilitation, little information is available to help land managers effectively reestablish native perennial vegetation across drylands....

Aims Plant-soil interactions are important drivers of plant productivity and community structure. Biocrusts – soil surface-dwelling biotic communities comprised of cyanobacteria, fungi, bryophytes, and/or lichens - are widespread in drylands globally. Biocrusts are described as “mantles of fertility” and have been shown to have facilitative, but sp...

Understanding the key factors that determine community structure is a central goal of ecology. While in plant community ecology there is wide consensus of the primary importance of dispersal limitations and abiotic filters in determining community structure, ecologists are just beginning to understand how biotic interactions restrict or enhance the...

Desert ecosystems are nitrogen-limited, and highly responsive to even small inputs of nitrogen. Recently, desert ecosystems have been affected by increasing levels of nitrogen deposition, which may lead to changes in greenhouse gas efflux. However, the effects of nitrogen deposition on these gases in the desert ecosystems remain poorly understood....

Effective mentoring is a key component of academic and career success that contributes to overall measures of productivity. Mentoring relationships also play an important role in mental health and in recruiting and retaining students from groups underrepresented in STEM fields. Despite these clear and measurable benefits, faculty generally do not r...

In dryland ecosystems, biocrusts coexist in patchy mosaics with vascular plants and can influence plant performance through modifications of soil stability, hydrology, microclimate, and fertility. Bio-crusts often have species-specific effects on vascular plant recruitment and hypothesized to promote native over exotic plant establishment. While th...

Woody plant expansion and infilling into nonwooded rangeland ecosystems have been observed worldwide. Such expansion may lead to declines in herbaceous understory plant communities and increased fuel loads in rangelands. Under the US National Fire Plan, fuel-reduction treatments have been implemented over vast expanses of western forest types to re...

Restoring dryland ecosystems is a global challenge due to synergistic drivers of disturbance coupled with unpredictable environmental conditions. Dryland plant species have evolved complex life-history strategies to cope with fluctuating resources and climatic extremes. Although rarely quantified, local adaptation is likely widespread among these s...

Scientific writing, while an indispensable step of the scientific process, is often overlooked in undergraduate courses in favor of maximizing class time devoted to scientific concepts. However, the ability to effectively communicate research findings is crucial for success in the biological sciences, as graduate students are encouraged to publish...

Local adaptation influences plant species’ responses to climate change and their performance in ecological restoration. Fine-scale physiological or phenological adaptations that direct demographic processes may drive intraspecific variability when baseline environmental conditions change. Landscape genomics characterize adaptive differentiation by...

Local adaptation is widespread across plant taxa and may influence the responses of species to climate change and the effectiveness of their use in ecological restoration. Natural populations are characterized by fine-scale physiological or phenological adaptations that drive intraspecific variability in responses to altered environmental condition...