Zachary Aanderud

Brigham Young University | BYU · Department of Plant and Wildlife Sciences

Biological soil crusts (biocrusts) play pivotal ecological roles in regulating nitrogen cycling within desert ecosystems. While acknowledging the essential role played by ammonia-oxidizing microorganisms in nitrogen transformation, there remains a paucity of understanding concerning how disturbances to biocrusts impact the diversity and spatial dis...

The dust cycle facilitates the exchange of particles among Earth's major systems, enabling dust to traverse ecosystems, cross geographic boundaries, and even move uphill against the natural flow of gravity. Dust in the atmosphere is composed of a complex and ever-changing mixture that reflects the evolving human footprint on the landscape. The emis...

Our understanding of the fundamental role that soil bacteria play in the structure and functioning of Earth's ecosystems is ever expanding, but insight into the nature of interactions within these bacterial communities remains rudimentary. Bacterial facilitation may enhance the establishment, growth, and succession of eukaryotic biota, elevating th...

Background and aims Wild fruit forests are vital reservoirs of germplasm genetic and biodiversity. Unfortunately, wild fruit forests of Central Asia are in the decline due to fungal disease and insect pest outbreaks. A health soil microbial community may help ameliorate the degradation of wild trees by increasing their systematic resistance, stabil...

The effectiveness of wetlands in sequestering nutrients and improving water quality relies on a suite of abiotic and biotic conditions. To more fully understand the restraints on nutrient removal, especially salinity and plant cover, we created field‐scale mesocosms and monitored nutrient sequestration with nutrient additions and isotopic pool dilu...

Background and aims The wild fruit forest in the Tianshan Mountains is a vital reservoir of germplasm resources for improving the genetic diversity of temperate fruit trees worldwide. In recent years, however, this forest ecosystem has been seriously threatened by outbreaks of diseases and insect pests as well as climate change. Analyses of soil mi...

The concepts of resistance, recovery, and resilience are in diverse fields from behavioral psychology to planetary ecology. These “three Rs” describe some of the most important properties allowing complex systems to survive in dynamic environments. However, in many fields—including ecology—our ability to predict resistance, recovery and resilience...

In Arctic catchments, bacterioplankton are dispersed through soils and streams, both of which freeze and thaw/flow in phase, seasonally. To characterize this dispersal and its potential impact on biogeochemistry, we collected bacterioplankton and measured stream physicochemistry during snowmelt and after vegetation senescence across multiple stream...

Anthropogenic long‐term nitrogen (N) deposition may dramatically impact biocrusts due to the overarching N limitation of soil biota in deserts. Even low levels of N may reach a critical loading threshold altering biocrust constituents and function. To identify the impact of chronic and continuous low levels of N deposition on biocrusts, we created...

Quantifying the routing of snowmelt to surface water is critical for predicting the impacts of atmospheric deposition and changing land use on water quality in montane catchments. To investigate solute sources and streamflow in the montane Provo River watershed (Utah, USA), we used time-series ⁸⁷Sr/⁸⁶Sr ratios sampled at three sites (Soapstone, Woo...

The hyperthermophilic anaerobic bacterium, Caldicellulosiruptor bescii, is effective in degrading and solubilizing lignocellulosic materials. Laboratory studies have characterized the chemistry of the process for crystalline cellulose and switchgrass, but the data are insufficient for engineering commercial plants to use C. bescii for pre-digestion...

Human modification of water and nutrient flows has resulted in widespread degradation of aquatic ecosystems. The resulting global water crisis causes millions of deaths and trillions of USD in economic damages annually. Semiarid regions have been disproportionately affected because of high relative water demand and pollution. Many proven water mana...

The complex relationship between ecosystem function and soil food web structure is governed by species interactions, many of which remain unmapped. Phagotrophic protists structure soil food webs by grazing the microbiome, yet their involvement in intraguild competition, susceptibility to predator diversity, and grazing preferences are only vaguely...

Mid-20th century mining in Naabeehó Bináhásdzo (Navajo Nation) polluted soil and groundwater with uranium and arsenic. The Diné and other indigenous residents of this region use groundwater for drinking, livestock, and irrigation, representing an environmental health risk. Currently, many individuals and communities on the Navajo Nation must purcha...

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes the coronavirus disease (COVID-19), is shed in feces and the viral ribonucleic acid (RNA) is detectable in wastewater. A nine-week wastewater epidemiology study of ten wastewater facilities, serving 39% of the state of Utah or 1.26 M individuals was conducted in April an...

SARS-CoV-2 RNA detection in wastewater is being rapidly developed and adopted as a public health monitoring tool worldwide. With wastewater surveillance programs being implemented across many different scales and by many different stakeholders, it is critical that data collected and shared are accompanied by an appropriate minimal amount of metainf...

Stream bacterioplankton communities, a crucial component of aquatic ecosystems and surface water quality, are shaped by environmental selection (i.e., changes in taxa abundance associated with more or less favorable abiotic conditions) and passive dispersal (i.e., organisms’ abundance and distribution is a function of the movement of the water). Th...

The Critical Zone is an important source of trace elements to headwater streams during the snowmelt runoff period, yet the mechanisms of trace element release are poorly characterized. To evaluate changes in water chemistry in response to snowmelt, we measured trace element and major ion concentrations at three sites in the upper Provo River in nor...

Bacteria in stream biofilms contribute to stream biogeochemical processes and are potentially sensitive to the substantial levels of pollution entering urban streams. To examine the effects of contaminants on stream biofilm bacteria in situ, we exposed growing biofilms to experimental additions of nutrients [nitrogen (N), phosphorus (P), and iron (...

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes the coronavirus disease (COVID-19), is shed in feces and the virus RNA is detectable in wastewater. A nine-week wastewater epidemiology study of ten wastewater facilities, serving 39% of the state of Utah or 1.26M individuals was conducted in April and May of 2020. COVID...

Wildfires destabilize biocrust, requiring decades for most biological constituents to regenerate, but bacteria may recover quickly and mitigate the detrimental consequences of burnt soils. To evaluate the short-term recovery of biocrust bacteria, we tracked shifts in bacterial community form and function in Cyanobacteria/lichen-dominated (shrub int...

The mechanisms of Hg and dissolved organic matter (DOM) transport from watersheds to streams remain unclear, especially in snowmelt dominated montane systems. We characterized total Hg concentrations and DOM characteristics during snowmelt by weekly and/or monthly sampling at three locations in the upper Provo River, northern Utah, over two water y...

Biological soil crusts (BSCs) consist of a diverse and highly integrated community of organisms that effectively colonize and collectively stabilize soil surfaces. BSCs vary in terms of soil chemistry and texture as well as the environmental parameters that combine to support unique combinations of organisms—including cyanobacteria dominated, liche...

Halophytes are plants that are adapted to grow in saline soils, and have been widely studied for their physiological and molecular characteristics, but little is known about their associated microbiomes. Bacteria were isolated from the rhizosphere and as root endophytes of Salicornia rubra, Sarcocornia utahensis, and Allenrolfea occidentalis, three...

Semi‐arid rangeland degradation is a reoccurring issue throughout the world. In the Great Basin of North America, seeds sown in the fall to restore degraded sagebrush (Artemisia spp.) steppe plant communities may experience high mortality in winter due to exposure of seedlings to freezing temperatures and other stressors. Delaying germination until...

[This corrects the article DOI: 10.3389/fmicb.2018.01401.].

Lakes worldwide are impacted by eutrophication and harmful algal or cyanobacteria blooms (HABs) due to excessive nutrients, including legacy P released from sediments in shallow lakes. Utah Lake (northern Utah, USA) is a shallow lake with urban development primarily on the east side of the watershed, providing an opportunity to evaluate HABs in rel...

Representative XRD pattern for Utah Lake sediment showing prominent quartz and calcite peaks. This pattern is for sample 3-D collected in November 2016. The height of the mineral peaks represents the abundance of minerals present in the sample. (TIF)

Sediment total P concentrations measured after sample digestion. (XLSX)

Sediment chemistry and mineralogy. (XLSX)

Pore water chemistry. (XLSX)

Water column chemistry. (XLSX)

Sampling sites for cyanobacteria cell count data shown in Fig 6. (TIF)

Sediment sequential extraction data. (XLSX)

Germination timing has a strong influence on direct seeding efforts, and therefore is a closely tracked demographic stage in a wide variety of wildland and agricultural settings. Predictive seed germination models, based on soil moisture and temperature data in the seed zone are an efficient method of estimating germination timing. We utilized Visu...

Wind-blown dust is an important source of trace metals, nutrients, and biological material to montane ecosystems. Mountain ranges in northern Utah are located downwind of multiple dust sources including the Great Basin Desert and the Wasatch Front urban area, providing an opportunity to investigate regional-scale differences in dust deposition chem...

Imbalances in C:N:P supply ratios may cause bacterial resource limitations and constrain biogeochemical processes, but the importance of shifts in soil stoichiometry are complicated by the nearly limitless interactions between an immensely rich species pool and a multiple chemical resource forms. To more clearly identify the impact of soil C:N:P on...

Besides performing multiple ecosystem services individually and collectively, biocrust constituents may also create biological networks connecting spatially and temporally distinct processes. In the fungal loop hypothesis rainfall variability allows fungi to act as conduits and reservoirs, translocating resources between soils and host plants. To e...

Besides performing multiple ecosystem services individually and collectively, biocrust constituents may also create biological networks connecting spatially and temporally distinct processes. In the fungal loop hypothesis, rainfall variability allows fungi to act as conduits and reservoirs, translocating resources between soils and host plants. To...

Water resources are increasingly impacted by growing human populations, land use, and climate changes, and complex interactions among biophysical processes. In an effort to better understand these factors in semiarid northern Utah, United States, we created a real-time observatory consisting of sensors deployed at aquatic and terrestrial stations t...

Groundwater inputs can impact river water quality but are difficult to disentangle from agricultural, urban, and storm runoff. To better understand the multiple processes affecting water quality, we used major solute and trace element concentrations with continuous measurements of flow rates and specific conductance to track temporal and spatial ch...

To stem wildfires, trees are being mechanically shredded into firebreaks with the resulting fine woody debris (FWD) potentially exerting immense control over soil and plants. We linked FWD-induced changes in microbial activity and nutrient availability to the frequency of Bromus tectorum and three native, perennial grasses across 31 piñon-juniper w...

Using Stable Isotope Probing to Explore food web dynamics in the soils of the McMurdo Dry Valleys, Antarctica, with special emphasis on the protozoan fauna.

Bacteria employ a diverse array of strategies to survive under extreme environmental conditions but maintaining these adaptations comes at an energetic cost. If energy reserves drop too low, extremophiles may enter a dormant state to persist. We estimated bacterial dormancy and identified the environmental variables influencing our activity proxy i...

Piñon (Pinus spp.) and juniper (Juniperus spp.) expansion and infilling in sagebrush (Artemisia L.) steppe communities can lead to high-severity fire and annual weed dominance. To determine vegetation response to fuel reduction by tree mastication (shredding) or seeding and then shredding, we measured cover for shrub and herbaceous functional group...

Extremophiles employ a diverse array of resistance strategies to thrive under harsh environmental conditions but maintaining these adaptations comes at an energetic cost. If energy reserves to drop too low, extremophiles may enter a dormant state of reduced metabolic activity to survive. Dormancy is frequently offered as a plausible explanation for...

Extremophiles employ a diverse array of resistance strategies to thrive under harsh environmental conditions but maintaining these adaptations comes at an energetic cost. If energy reserves to drop too low, extremophiles may enter a dormant state of reduced metabolic activity to survive. Dormancy is frequently offered as a plausible explanation for...

Bromus tectorum (cheatgrass) has widely invaded the Great Basin, U.S.A. The sporadic natural phenomenon of complete stand failure (‘die-off’) of this invader may present opportunities to restore native plants. A recent die-off in Nevada was precision-planted with seeds of the native grasses Poa secunda (Sandberg bluegrass) and Elymus elymoides (bot...

Aeolian dust is an important physical and chemical flux to mountain snowpack with potentially significant contributions of trace elements to mountain streams during snowmelt. However, it is difficult to differentiate solute contributions from dust relative to soil erosion and bedrock weathering. Sr isotopes show promise as a tracer of the soluble f...

Numerous natural and anthropogenic processes in a watershed produce the geochemical composition of a river, which can be altered over time by snowmelt and rainfall events and by built infrastructure (i.e., dams and diversions). Trace element concentrations coupled with isotopic ratios offer valuable insights to disentangle the effects of these proc...

Dormancy is a life history trait that may have important implications for linking microbial communities to the functioning of natural and managed ecosystems. Rapid changes in environmental cues may resuscitate dormant bacteria and create pulses of ecosystem activity. In this study, we used heavy-water (H¹⁸2O) stable isotope probing (SIP) to identif...

Climate change effects on plants are expected to be primarily mediated through early life stage transitions. Snowfall variability, in particular, may have profound impacts on seedling recruitment, structuring plant populations and communities, especially in mid-latitude systems. These water-limited and frequently invaded environments experience tre...

Background/Question/Methods Bacterial dormancy is a common life history strategy to weather temporal fluctuations of resources or stresses to wait until more “optimal” conditions are present for metabolic activity and growth. In extreme environments; however, the overriding effects of a constant stress constrains the need or benefit of bacteria e...

Background/Question/Methods To stem catastrophic wildfires and create firebreaks, whole Juniperus osteosperma trees are being mechanically shredded into coarse woody debris (CWD) and deposited on soils. CWD often alters belowground processes, ultimately increasing or decreasing the availability of limiting nutrients for establishing plant species...

Although the desert moss Syntrichia caninervis Mitt. is extremely desiccation tolerant, it still requires water and photosynthates for growth. The ecological significance of the leaf angle in maintaining a balance between water and light availability is critical to its survival. Active leaf repositioning balances water and light availability follow...

Although numerous studies have investigated changes in soil microbial communities across space, questions about the temporal variability in these communities and how this variability compares across soils have received far less attention. We collected soils on a monthly basis (May to November) from replicated plots representing three land-use types...

Background/Question/Methods One of the overarching goals of microbial ecology is to understand what key abiotic and biotic environmental factors are responsible for maintaining high levels of microbial diversity. This is complicated by the fact that soil bacteria experience a high degree of resource variability, and a large fraction of the bacter...

Background/Question/Methods Seedling emergence is a fundamental limitation to ecosystem restoration efforts attempting to revegetate burned ecosystems. Following seeding, seeds of native plants usually germinate at high levels in fall and must contend with extreme winter soil conditions before establishing in spring. Many germinated seeds do not e...

Background/Question/Methods As global climates warm, rainfall regimes are being altered with future climate scenarios forecasting extended periods of drought and increased frequency of extreme rainfall events. Rainfall change will influence soil moisture dynamics; alter patterns of resource availability and physiological stress on soil bacteria;...

Background/Question/Methods Biological soil crusts are complex mosaics of cyanobacteria, green algae, lichens, mosses, microfungi, and other bacteria and may constitute up to 70% of living biomass in desert ecosystems. Within these crusts, cyanobacteria: glue soil particles together and create a matrix that protects soil surfaces from wind and wa...

The biodiversity of microbial communities has important implications for the stability and functioning of ecosystem processes. Yet, very little is known about the environmental factors that define the microbial niche and how this influences the composition and activity of microbial communities. In this study, we derived niche parameters from physio...