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Life Sciences

2022

Drought

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Evaluation For Using Expended Bioelectrochemical Systems As Soil Amendments For Improved Corn Plant Growth And A Drought Resistant Soil., Jackson Lee Sauers Dec 2022

Evaluation For Using Expended Bioelectrochemical Systems As Soil Amendments For Improved Corn Plant Growth And A Drought Resistant Soil., Jackson Lee Sauers

Theses and Dissertations

A long-held practice is to mix agricultural soil with a soil amendment to improve growing conditions in crops. A common soil amendment is biosolids produced from both municipal and dairy wastewater due to the macro- and micronutrients within it. Both the agricultural and wastewater industries are participating in the Circular Economy concept (CEC). Two experiments explored using expended bioelectrochemical systems (BES) that treated either synthetic dairy wastewater (DWW) or synthetic municipal wastewater (SWW) as soil amendments to improve corn plant growth when treated with three different nutrient treatments: 100%- 50%- and 0% Hoagland Nutrient Solutions. Biochar and used terracotta clay …


Drought Levels In Nevada Counties, 2022, Julianna Jovillar, Caitlin J. Saladino, William E. Brown Jr. Dec 2022

Drought Levels In Nevada Counties, 2022, Julianna Jovillar, Caitlin J. Saladino, William E. Brown Jr.

Environment

This fact sheet synthesizes data on drought levels within Nevada counties from the National Integrated Drought Information System (NIDIS) in 2022. The information presented in this document focuses on the breakdown of the number of Nevada residents affected by the droughts within each county and the drought experience in each county.


The Impact Of Glycine Betaine Applications On Drought Response In Wild Blueberries, Abigail Fisher Dec 2022

The Impact Of Glycine Betaine Applications On Drought Response In Wild Blueberries, Abigail Fisher

Honors College

Wild blueberries are an economically important crop for Maine, and with warming temperatures leading to increased periods of drought and increased soil moisture deficits, it is important to find new ways to combat the effects of drought. In this study, we aimed to look at the effect of foliar-applied glycine betaine applications on wild lowbush blueberries in both field and greenhouse experiments. The product being tested was Bluestim, a foliar-applied product containing >96% pure glycine betaine sold by Biobest. The product is claimed to work as an osmoprotectant allowing the plant to maintain turgor pressure and protect enzymes and macromolecules …


Plant Responses To Drought In A Semiarid Grassland: An Isotopic Approach, Elizabeth V. Fain Oct 2022

Plant Responses To Drought In A Semiarid Grassland: An Isotopic Approach, Elizabeth V. Fain

Biology ETDs

Dryland ecosystems are facing unprecedented climate extremes as a result of global climate change. Water is the most limiting factor in dryland ecosystems, therefore plants in drylands have developed crucial water-use strategies for drought survival. It is important to understand plant physiological responses to water stress as drylands are projected to experience more frequent, severe droughts in the coming decades. To test how plants respond to drought in a semiarid grassland, we measured δ13C, δ15N, and C/N ratio of common C3 and C4 plants (Bouteloua gracilis, B. eriopoda, Pleuraphis jamesii, Salsola tragus, Machaeranthera pinnatifida, …


Effect Of Water Stress On Weed Germination, Growth Characteristics, And Seed Production: A Global Meta-Analysis, Mandeep Singh, Resham Thapa, Meetpal Singh Kukal, Suat Irmak, Steven Mirsky, Amit J. Jhala Oct 2022

Effect Of Water Stress On Weed Germination, Growth Characteristics, And Seed Production: A Global Meta-Analysis, Mandeep Singh, Resham Thapa, Meetpal Singh Kukal, Suat Irmak, Steven Mirsky, Amit J. Jhala

Department of Agronomy and Horticulture: Faculty Publications

Weeds compete with crops for soil moisture, along with other resources, which can impact the germination, growth, and seed production of weeds; however, this impact has not been systematically recorded and synthesized across diverse studies. To address this knowledge gap, a global meta-analysis was conducted using 1,196 paired observations from 86 published articles assessing the effect of water stress on weed germination, growth characteristics, and seed production. These studies were conducted and published during 1970 through 2020 across four continents (Asia, Australia, Europe, and North America). Imposed water stress was expressed as solution osmotic potential (ψsolution), soil water potential (ψsoil), …


Climate Impacts On North American Quail, Shelby M. Perry, Erin Moser, Jeffrey G. Whitt, Kelly S. Reyna Sep 2022

Climate Impacts On North American Quail, Shelby M. Perry, Erin Moser, Jeffrey G. Whitt, Kelly S. Reyna

National Quail Symposium Proceedings

North America’s quail population trends are often linked to regional climate. Extreme climate events such as severe drought, hard freezes, or excessive winter precipitation can reduce quail populations by as much as 84%. Above-average spring and summer temperatures coincident with drought can reduce the laying season for quail by ≤60 days. Exposure of quail eggs to high temperatures during preincubation can initiate and alter embryonic development. Here, we review the impacts of extreme climate events and a changing climate on the survival, reproduction, and population trends of 6 North American quail species: California quail (Callipepla californica), Gambel’s quail …


County-Level View Of Irrigation Trends In Utah And The West, Matt Yost, Britta L. Schumacher, Luree Johnson, Emily Burchfield, Burdette Barker Sep 2022

County-Level View Of Irrigation Trends In Utah And The West, Matt Yost, Britta L. Schumacher, Luree Johnson, Emily Burchfield, Burdette Barker

All Current Publications

We explored water use management and trends in irrigated agriculture in the U.S. West using operator-level USDA-NASS Farm and Ranch Irrigation Survey (FRIS)/Irrigation and Water Management Survey (IWMS) data aggregated for the first time to the county instead of state scale. Our hope is that this study will guide water managers in developing regional conservation programs, inform extension and research initiatives related to irrigation, promote grower-informed water conservation education, and provide researchers with key information regarding if, how, and why growers consider water conservation in irrigation decision-making.


Guide To Drought Tolerance Of Utah Field Crops, Matt Yost, Tina Sullivan, Dakota Boren, Luree Johnson, Melanie Mills, Earl Creech, Boyd Kitchen, Randall Violett Aug 2022

Guide To Drought Tolerance Of Utah Field Crops, Matt Yost, Tina Sullivan, Dakota Boren, Luree Johnson, Melanie Mills, Earl Creech, Boyd Kitchen, Randall Violett

All Current Publications

Crop variety selection is one of the most important choices on the farm. Crop genetics determine a significant portion of the yield potential and resource use efficiency. Crop types and genetics that use water more efficiently will become increasingly important as water becomes scarcer. Throughout Utah and the Western United States, water availability is decreasing due to various factors, including reduced snowpack and rapid urban growth. Alfalfa, other hay, small grains, and corn are grown on more acres than any other crops in Utah and much of the Intermountain West. These crops all have varieties, hybrids, and cultivars with the …


Watering The Desert, Draining The Oasis: Navigating Drought, Development, And Irrigation Politics In The Draa Valley, Morocco, Jamie Fico Aug 2022

Watering The Desert, Draining The Oasis: Navigating Drought, Development, And Irrigation Politics In The Draa Valley, Morocco, Jamie Fico

Theses - ALL

No abstract provided.


Functional Traits’ Annual Variation Exceeds Nitrogen-Driven Variation In Grassland Plant Species, George R. Wheeler, Chad Brassil, Johannes M. H. Knops Aug 2022

Functional Traits’ Annual Variation Exceeds Nitrogen-Driven Variation In Grassland Plant Species, George R. Wheeler, Chad Brassil, Johannes M. H. Knops

School of Biological Sciences: Faculty Publications

Effective application of functional trait approaches to ecological questions requires understanding the patterns of trait variation within species as well as between them. However, few studies address the potential for intraspecific variation to occur on a temporal basis and, thus, for trait-based findings to be contingent upon sampling year. To quantify annual variation in the functional traits of grassland plant species, we measured specific leaf area, leaf dry matter content, plant height, and chlorophyll content in 12 shortgrass prairie plant species. We repeated these measurements across 4 years, both in long-term nitrogen addition plots and in corresponding control plots. Three …


Drought Tolerance Of Artemisia Tridentata In Response To Herbivory And Mycorrhizal Colonization, Mathew Geisler Aug 2022

Drought Tolerance Of Artemisia Tridentata In Response To Herbivory And Mycorrhizal Colonization, Mathew Geisler

Boise State University Theses and Dissertations

Interactions with other organisms can affect a plant’s ability to cope with drought. The re-establishment of Artemisia tridentata, a keystone species of the sagebrush steppe, is often limited by summer drought. This study investigated the effect of two biotic factors, herbivory and symbiosis with arbuscular mycorrhizal fungi (AMF), on the drought tolerance of Artemisia tridentata ssp. wyomingensis (Wyoming big sagebrush) seedlings. For this purpose, I conducted two separate but concurrent field experiments. The herbivory experiment had three treatments: seedlings without tree protectors and seedlings within Vexar or metal-mesh tree protectors. In the mycorrhizal experiment, all seedlings were within metal-mesh …


Hidden Mechanisms Of Climate Impacts In Western Forests: Integrating Theory And Observation For Climate Adaptation, Sara J. Germain Aug 2022

Hidden Mechanisms Of Climate Impacts In Western Forests: Integrating Theory And Observation For Climate Adaptation, Sara J. Germain

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Fire, insects, and disease are necessary components of forest ecosystems. Yet, climate change is intensifying these tree stressors and creating new interactions that threaten forest survival. This dissertation combined field observations with statistical predictions of changing disturbances in western forests to identify 1) how conventional models may underestimate future forest loss, and 2) how positive relationships between trees may be exploited by managers to prevent forest loss.

In Chapter II, I tested whether increasingly extreme weather with climate change increases Pacific yew extinction risk. I found that conventional modeling methods underestimated local extinction risk because trees were adapted to a …


Impacts Of The Changing Pacific On North American Drought, Atmospheric Rivers, And Explosive Cyclones, Jacob Stuivenvolt-Allen Aug 2022

Impacts Of The Changing Pacific On North American Drought, Atmospheric Rivers, And Explosive Cyclones, Jacob Stuivenvolt-Allen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The impacts of specific weather events can vary greatly from year to year. Much of these impacts depend heavily on the frequency of impactful weather which is constrained by the state of the climate system each year. This research focuses largely on the impacts that climate oscillations from year-to-year or even from decade-to-decade have on the frequency of impactful weather. There are numerous examples of impactful weather that impact North America, but this work focuses on drought in the western United States, atmospheric rivers in Northern California and rapidly developing winter storms along the east coast. While seemingly disparate events, …


Quantifying And Predicting Drought Performance In Woody Semi-Arid Seedlings In South Texas: Implications For Enhancing Drought Resilience In Restoration, Zarek Contreras Aug 2022

Quantifying And Predicting Drought Performance In Woody Semi-Arid Seedlings In South Texas: Implications For Enhancing Drought Resilience In Restoration, Zarek Contreras

Theses and Dissertations

Increasingly frequent and severe droughts in the Lower Rio Grande Valley National Wildlife Refuge have been observed to cause large variation in species-specific mortality patterns in young seedlings, spanning 6 – 43 % mortality within the first year. To understand the underlying mechanisms behind this, we subjected seedlings of five woody semi-arid species (Celtis pallida, Forestiera angustifolia, Sideroxylon celastrinum, Phaulothalmnus spinescens, and Zanthoxylum fagara) to a point-of-no-return drought experiment in order to (1) identify potential metrics capable of predicting species wilting and mortality responses, and (2) to understand the underlying mechanisms that correspond to species drought performance …


Understory Plant Communities Show Resistance To Drought, Hurricanes, And Experimental Warming In A Wet Tropical Forest, Aura M. Alonso-Rodríguez, Tana E. Wood, Jamarys Torres-Díaz, Molly A. Cavaleri, Sasha C. Reed, Benedicte Bachelot Jul 2022

Understory Plant Communities Show Resistance To Drought, Hurricanes, And Experimental Warming In A Wet Tropical Forest, Aura M. Alonso-Rodríguez, Tana E. Wood, Jamarys Torres-Díaz, Molly A. Cavaleri, Sasha C. Reed, Benedicte Bachelot

Michigan Tech Publications

Global climate change has led to rising temperatures and to more frequent and intense climatic events, such as storms and droughts. Changes in climate and disturbance regimes can have non-additive effects on plant communities and result in complicated legacies we have yet to understand. This is especially true for tropical forests, which play a significant role in regulating global climate. We used understory vegetation data from the Tropical Responses to Altered Climate Experiment (TRACE) in Puerto Rico to evaluate how plant communities responded to climate warming and disturbance. The TRACE understory vegetation was exposed to a severe drought (2015), 2 …


Using Satellite Imagery To Compare Land Cover And Water Resources In Two Counties Of The Nebraska Sandhills, Gabrielle Baker, Mary Ann Vinton Jul 2022

Using Satellite Imagery To Compare Land Cover And Water Resources In Two Counties Of The Nebraska Sandhills, Gabrielle Baker, Mary Ann Vinton

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

The Nebraska Sandhills comprise the most intact grassland habitat in the world and 95% of land use consists of low intensity cattle grazing. Water is a key resource for cattle and for growing hay forage in this semi-arid grassland. Ranchers rely on either naturally occurring wet meadows or center pivot irrigation systems (CPIS) to produce hay. With the possibility of climate change creating more frequent extreme weather events, more flooding events or severe droughts could affect land and water resources in the Sandhills. With potentially more wet/dry extremes in the future, an understanding of the way water resources respond, and …


Water Availability Dictates How Plant Traits Predict Demographic Rates, Alice E. Stears, Peter B. Adler, Dana M. Blumenthal, Julie A. Kray, Kevin E. Mueller Jul 2022

Water Availability Dictates How Plant Traits Predict Demographic Rates, Alice E. Stears, Peter B. Adler, Dana M. Blumenthal, Julie A. Kray, Kevin E. Mueller

Biological, Geological, and Environmental Faculty Publications

A major goal in ecology is to make generalizable predictions of organism responses to environmental variation based on their traits. However, straightforward relationships between traits and fitness are rare and likely to vary with environmental context. Characterizing how traits mediate demographic responses to the environment may enhance the predictions of organism responses to global change. We synthesized 15 years of demographic data and species-level traits in a shortgrass steppe to determine whether the effects of leaf and root traits on growth and survival depended on seasonal water availability. We predicted that (1) species with drought-tolerant traits, such as lower leaf …


Water Availability Dictates How Plant Traits Predict Demographic Rates, Alice E. Stears, Peter B. Adler, Dana M. Blumenthal, Julie A. Kray, Kevin E. Mueller, Troy W. Ocheltree, Kevin R. Wilcox, Daniel C. Laughlin Jun 2022

Water Availability Dictates How Plant Traits Predict Demographic Rates, Alice E. Stears, Peter B. Adler, Dana M. Blumenthal, Julie A. Kray, Kevin E. Mueller, Troy W. Ocheltree, Kevin R. Wilcox, Daniel C. Laughlin

Wildland Resources Faculty Publications

A major goal in ecology is to make generalizable predictions of organism responses to environmental variation based on their traits. However, straightforward relationships between traits and fitness are rare and likely to vary with environmental context. Characterizing how traits mediate demographic responses to the environment may enhance the predictions of organism responses to global change. We synthesized 15 years of demographic data and species-level traits in a shortgrass steppe to determine whether the effects of leaf and root traits on growth and survival depended on seasonal water availability. We predicted that (1) species with drought-tolerant traits, such as lower leaf …


Transcriptional Analysis Of Maize Under Drought Stress And The Impact Of Plant Maturity, Oliver J. Oviedo May 2022

Transcriptional Analysis Of Maize Under Drought Stress And The Impact Of Plant Maturity, Oliver J. Oviedo

Biology ETDs

Climate change related drought is projected to harm maize production. Water use strategies can help mitigate the impact of drought on crop yield. However, little is known about maize metabolic response to drought at different developmental stages. To shed light on this, drought conditions were applied to maize at the six-leaf stage (V6), twelve leaf stage (V12), and tassel stage (VT). V6 and VT took eight days to achieve a low stomatal conductance threshold, but V12 took 16 days. Differential gene expression analysis of the transcriptome indicates that V6 showed the most response with 53 impacted metabolic pathways, many of …


Biodiversity And Global Change In Terrestrial Ecosystems, Timothy J. Ohlert May 2022

Biodiversity And Global Change In Terrestrial Ecosystems, Timothy J. Ohlert

Biology ETDs

Terrestrial ecosystems are critical to human and ecological processes but many gaps in our knowledge remain regarding how terrestrial plant communities assemble and respond to global change. I used field experiments distributed around the world, including long-term experiments from the Sevilleta National Wildlife Refuge (SNWR) in New Mexico and deserts of the southwestern U.S., to evaluate the consequences of drought and other abiotic stressors on plant communities. Dominant grasses were particularly important for the productivity and structure of grasslands at SNWR. In general, the structure of desert plant communities had high resistance to extreme drought, though grasses and other perennial …


Breeding Soybean [Glycine Max (L) Merr.] Under Reduced Irrigation, Francia Seconde Ravelombola May 2022

Breeding Soybean [Glycine Max (L) Merr.] Under Reduced Irrigation, Francia Seconde Ravelombola

Graduate Theses and Dissertations

Soybean [Glycine max (L) Merr.], a legume species native to East Asia in the Fabaceae family, ranks among the most important food crops in the world. It is widely grown and known for its high protein and oil concentration. Soybean is valuable because its seeds have multiple applications in food, feed, pharmaceutical, and industrial enterprises. Even though seed yield is the most important trait, breeders have recently given a significant attention to quality traits, such as high protein or modified oil concentration. Soybean seed protein inheritance has been extensively studied; however, genetics of high-protein ‘BARC-7’ soybean are still unknown.On the …


Improving Water And Plant Growth Regulator (Pgr) Management Practices In Cotton: Cultivar Physiological Responses And Pgr Rates, Kurt Wedegaertner May 2022

Improving Water And Plant Growth Regulator (Pgr) Management Practices In Cotton: Cultivar Physiological Responses And Pgr Rates, Kurt Wedegaertner

Masters Theses

Cotton (Gossypium hirsutum L.) is grown in an increasingly unpredictable climate and often under rainfed conditions. Without irrigation to alleviate common drought conditions, cultivar selection becomes a primary tool in mitigating the negative effects of water-deficit stress. Cultivars can differ in water use under water-limited environments, which can affect crop performance. Moreover, cotton management must involve balancing vegetative and reproductive growth through the use of plant growth regulators (PGR) due to the plant’s perennial growth pattern. The efficacy of PGRs are dependent on many variables including environmental conditions, irrigation, and genetics (cultivar). In 2020 and 2021, a series of …


Elucidating The Cellular Physiology Of Glyphosate Resistance In Palmer Amaranth (Amaranthus Palmeri) Using Integrated Omics Approaches, Pawanjit Kaur Sandhu May 2022

Elucidating The Cellular Physiology Of Glyphosate Resistance In Palmer Amaranth (Amaranthus Palmeri) Using Integrated Omics Approaches, Pawanjit Kaur Sandhu

All Theses

The evolution of resistance to herbicides in weeds poses a major threat to agricultural production systems. To date, herbicide resistance has been reported against 21 modes of action in 266 weed species across 71 countries. More than 50 weed species have developed resistance against glyphosate, the most widely used herbicide worldwide. Although several mechanisms of glyphosate resistance have been discovered, our understanding of alterations in the cellular physiology of glyphosate-resistant weed biotypes, and the induction of the resistance mechanisms remains limited. This knowledge is critical to developing sustainable weed management practices and for a comprehensive understanding of plant stress adaptations. …


Spring Forage Stash Module To Prevent Forage Crisis On Uruguayan Livestock Systems: An Evaluation Based On Model Simulations, M. Pereira Machín, F. Dieguez Cameroni Feb 2022

Spring Forage Stash Module To Prevent Forage Crisis On Uruguayan Livestock Systems: An Evaluation Based On Model Simulations, M. Pereira Machín, F. Dieguez Cameroni

IGC Proceedings (1997-2023)

In Uruguay, rangeland cattle production systems support national economy by beef exportation chain and economic inputs to the country. Soil hydric stress episodes results to forage crisis on grassland-based production systems, having high impact on its trajectory and leaving sequels at several farm levels mainly on rearing cattle systems in drought sensitive regions of the country. In that context, the proposal is to create a spring forage stash module, with a simple management rules as a mechanism to build stability to farms and to buffering drought impact. The concept is to differ spring forage (season with low variation coefficient on …


Species Richness Increased Yield Stability In Intensively Managed Grasslands Subjected To Experimental Drought, J. A. Finn, M. Suter, E. Haughey, D. Hofer, A. Lüscher Feb 2022

Species Richness Increased Yield Stability In Intensively Managed Grasslands Subjected To Experimental Drought, J. A. Finn, M. Suter, E. Haughey, D. Hofer, A. Lüscher

IGC Proceedings (1997-2023)

Climate change is expected to cause an increase in the frequency and intensity of drought events. Over two years we investigated the effects of experimentally imposed drought on intensively managed grassland communities (5 m x 6 m plots) of varying richness (1, 2 and 4 species), and comprising four species (Lolium perenne L., Cichorium intybus L., Trifolium repens L., Trifolium pratense L.). In each year a summer drought period of nine weeks with complete exclusion of precipitation was simulated, inducing severe drought stress at Reckenholz (Zürich, Switzerland), and extreme drought stress at Wexford (Ireland). Mean yield and plot-to-plot variance …


Elevated Co2 And Extreme Climatic Events Modify Nitrogen Content And Ruminal Protein Digestion Of Temperate Grassland, V. Niderkorn, C. Picon-Cochard Feb 2022

Elevated Co2 And Extreme Climatic Events Modify Nitrogen Content And Ruminal Protein Digestion Of Temperate Grassland, V. Niderkorn, C. Picon-Cochard

IGC Proceedings (1997-2023)

This study was aimed at analyzing changes in nitrogen (N) content and in vitro protein rumen digestion of an upland grassland exposed to climate changes in controlled conditions. Monoliths of grassland were inserted in 12 macrocosms in which climatic conditions for the 2050s were simulated (i.e., +2.3°C and 33 mm less precipitation compared to the current climatic conditions). Six of them were subjected to ambient CO2 (390 ppm) while the other six were subjected to elevated CO2 (520 ppm). After four months, an extreme climatic event (ECE) consisting of four weeks of reducted precipitation (-50%) followed by two …


Climate Change Threats To Semi-Arid Transhumance Grazing Systems: Proposals For Adaptation In Cabo Verde, J. F. Castro, S. Tavares, M. Castro Feb 2022

Climate Change Threats To Semi-Arid Transhumance Grazing Systems: Proposals For Adaptation In Cabo Verde, J. F. Castro, S. Tavares, M. Castro

IGC Proceedings (1997-2023)

Global warming has changed the rainfall regime in the Sahelian region, endangering and widespread poverty and chronic famines in Cape Verde, where rural communities' well-being and food security depend on rainy agriculture. Local responses to rainfall new patterns and scarcity have been livestock reduction with significant revenue losses. Together with dry mist occurrences, these environmental constraints demand to define priority actions to adapt and mitigate climate change's direct impacts. According to fifty household inquiries, this work explains the transhumant grazing practices on a semi-arid plateau in Tarrafal (Santiago, Cabo Verde), prospecting adaptation alternatives for sustainability. We related grazing patterns and …


Precipitation Is A Strong Predictor Of Airborne Ammonia Levels., Bridger Jorgensen, Casey Olson, Connor Snow Feb 2022

Precipitation Is A Strong Predictor Of Airborne Ammonia Levels., Bridger Jorgensen, Casey Olson, Connor Snow

Research on Capitol Hill

USU senior Connor has lived in the Uintah Basin all his life and studies kinesiology. Senior Casey, a Cache Valley native, studies climate science and works at the Utah Climate Center. Junior Bridger, also of Cache Valley, studies nutrition science. They led and funded this project through a student grant. Casey was alarmed by the ammonia data he was collecting at the Climate Center. “I immediately began to wonder how this issue would evolve over the coming decades.” The three teamed up to take a look at how Logan’s record-breaking amount of ammonia in our air is impacting those who …


Multiyear Defoliations In Southern New England Increases Oak Mortality, Jeffrey S. Ward, Chad C. Jones, Joseph P. Barsky Feb 2022

Multiyear Defoliations In Southern New England Increases Oak Mortality, Jeffrey S. Ward, Chad C. Jones, Joseph P. Barsky

Botany Faculty Publications

After decades of multiyear defoliation episodes in southern New England, Lymantria dispar dispar (LDD; previously gypsy moth) populations collapsed with the appearance of the LDD fungus in 1989. Multiyear defoliations did not occur again until 2015-2018. To assess the impact of the return of multiyear defoliations, we examined 3095 oaks on 29 permanent study areas in Connecticut and Rhode Island that were established at least eleven years before the latest outbreaks. Pre-defoliation stand level oak mortality averaged 2% (three-year basis). Post-defoliation mortality did not differ between managed and unmanaged stands, but was much higher in severely defoliated stands (36%) than …


Disturbance Reduces Fungal White-Rot Litter Mat Cover In A Wet Subtropical Forest, D. Jean Lodge, Ashley E. Van Beusekom, Grizelle González, Mareli Sánchez-Julia, Sarah Stankavich Feb 2022

Disturbance Reduces Fungal White-Rot Litter Mat Cover In A Wet Subtropical Forest, D. Jean Lodge, Ashley E. Van Beusekom, Grizelle González, Mareli Sánchez-Julia, Sarah Stankavich

USDA Forest Service / UNL Faculty Publications

Fungi that bind leaf litter into mats and produce white-rot via degradation of lignin and other aromatic compounds influence forest nutrient cycling and soil fertility. Extent of white-rot litter mats formed by basidiomycete fungi in Puerto Rico decreased in response to disturbances—a simulated hurricane treatment executed by canopy trimming and debris addition in 2014, a drought in 2015, a treefall, and two hurricanes 10 days apart in September 2017. Percent fungal litter mat cover ranged from 0.4% after Hurricanes Irma and Maria to a high of 53% in forest with undisturbed canopy prior to the 2017 hurricanes, with means mostly …