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Marta P. Lyons

Publications and source records attributed to Marta P. Lyons.

13 recordsLinked to original sources
USGS2025

Effects of climate change on midwestern ecosystems: North American bog and fen

The North American Bog and Fen ecosystem may be increasingly vulnerable to climate stressors, particularly water deficits and warming temperatures. These peat-forming wetlands, found at the southern extent of their range in the Midwest, depend on relatively stable hydrological and thermal conditions. Climate change may disrupt these conditions through projected declines in summer precipitation, increases in summer vapor pressure deficit and temperature, and longer periods of warmth throughout the year. These changes could lower water tables, accelerate aerobic decomposition, and alter peat-accumulating processes that define bogs and fens. Water deficits, compounded by warmer conditions, may reduce moss and sedge productivity and promote peat subsidence and compaction. Collectively, these impacts may compromise the structural integrity of this ecosystem and reduce its capacity to store carbon, maintain unique microhabitats, and support moisture-dependent species.

Illinois, Indiana, Iowa, Michigan, Minnesota, Miss↗
USGS2025

Effects of climate change on midwestern ecosystems: Eastern North American temperate freshwater marsh, wet meadow and shrubland

The Eastern North American Temperate Freshwater Marsh, Wet Meadow and Shrubland is a hydrologically dynamic ecosystem highly sensitive to shifts in water availability. Across the Midwest, climate change is expected to intensify two primary stressors, flooding and drought, resulting in increased hydrologic variability that may threaten the persistence of these wetlands. Increased spring precipitation and more frequent extreme rainfall events are projected to cause deeper, longer-lasting inundation, while rising temperatures, reduced snowpack, and heightened evaporative demand are likely to increase the frequency and severity of droughts. Changes in hydrology may significantly alter both habitat structure and community composition. Physical disturbance from scouring and erosion may intensify, while nutrient and sediment loading from surrounding land uses may lead to eutrophication and terrestrialization. Vegetation zonation is likely to become destabilized under more extreme hydrological conditions, with flood-tolerant or droughtadapted species replacing those with narrower hydrologic tolerances. The two habitat groups within this broader ecosystem show differing vulnerabilities. The Eastern North American Freshwater Marsh, including both Great Lakes coastal and inland systems, is considered among the most hydrologically dynamic and disturbance-prone wetland types. Vegetation in these marshes is typically stratified along water depth gradients, forming distinct zones that depend on variable hydrology to persist, but deep or prolonged inundation can disrupt this zonation and reduce plant diversity. In contrast, the Midwest Wet Prairie, Wet Meadow and Shrub Swamp, generally lacks persistent surface water and relies on precipitation and snowmelt to maintain seasonal saturation. As a result, this habitat group is especially prone to drying and potentially susceptible to woody encroachment and shifts toward drier-adapted plant communities. Across both habitat groups, invasive species are expected to gain a competitive edge under future climate conditions. Invasive wetland plants often exhibit high plasticity and can tolerate a wide range of disturbances and hydrologic conditions, allowing them to expand rapidly during both flood and drought periods. Interacting pressures underscore the growing vulnerability of the Eastern North American Temperate Freshwater Marsh, Wet Meadow and Shrubland under future climate scenarios.

Illinois, Indiana, Iowa, Michigan, Minnesota, Miss↗
USGS2025

Potential effects of sea level rise and high tide flooding on Laterallus jamaicensis jamaicensis (eastern black rail) coastal breeding areas

Laterallus jamaicensis jamaicensis (eastern black rails; Gmelin, 1789) are facing increasing risk from flooding in coastal breeding habitats because of rising sea levels combined with standard high tide flooding. In this report, we examine regional differences in relative rates of sea level rise, days in the breeding season above historical high tide flooding thresholds, future inundation of current (2021) emergent wetlands, and potential marsh resiliency for the breeding distribution of the eastern black rail across the Atlantic and U.S. Gulf coasts. By midcentury (2050), two sea level rise scenarios (intermediate low and intermediate) indicate that areas analyzed in Texas and the Mid-Atlantic will experience at least minor flood levels for more than half of the breeding season. By the end of the century (2100), all tidal gages in the Atlantic and U.S. Gulf coasts are projected to experience at least moderate flood levels for most of the current (April–September) eastern black rail breeding season. In some areas like New Jersey, this translates to inundation for most of the emergent wetlands in the representative parishes and counties analyzed in this report. In other parts of the coastal distribution, estimates of increases in inundation are lower or more variable, stemming from differences in the elevation of existing emergent marsh, especially at the herbaceous wetland/woody wetland transition zone. Sea level rise and tidal flooding are not projected to pose an equal risk across the coastal distribution of the eastern black rail, leading to variation in risk of nest loss because of flooding. The degree to which these wetlands and birds will adapt to changing sea level and salinity depends on a range of factors including future expansion of developed areas and the ability of marsh areas to move inland. Restoration and active management of coastal wetland areas may be necessary to maintain appropriate breeding habitat.

Atlantic Coast, Gulf Coast↗
USGS2025

Effects of climate change on midwestern ecosystems: Appalachian – Interior – Northeast Mesic Forest

The Appalachian-Interior-Northeast Mesic Forest ecosystem, historically buffered by cool, moist conditions, may experience significant stress under future climate change, particularly due to intensifying droughts and milder winters in the midwestern United States. Droughts are expected to intensify in frequency and severity, depleting soil moisture, increasing tree mortality, and reshaping species composition. Increasing aridity and disrupted hydrologic cycles will likely accelerate soil erosion, deplete nutrients, and heighten wildfire risk. Meanwhile, milder winters may reduce snowpack insulation, increase freeze-thaw cycles, and alter growing seasons, potentially amplifying cold stress, disrupting phenology, and contributing to shifts in habitat structure and community composition. While easing winter severity may temporarily boost plant productivity and facilitate species migration into and throughout the Midwest, it can also increase the risk of frost damage for early-leafing trees and disrupt ecological relationships, such as plant-pollinator interactions. Together, these stressors may drive fundamental shifts in habitat structure and community composition, favoring drought-, fire-, and cold-tolerant species, while historically dominant, moisture-dependent species decline. Species with limited drought resistance, such as those with shallow roots or low water-use efficiency, may be especially vulnerable, while drought-adapted taxa could gain a competitive advantage. This shift could trigger a departure from over a century of mesophication in the Appalachian-Interior-Northeast Mesic Forest, which has favored shade-loving, moisture-dependent species in fire-suppressed landscapes. As a result, these forests may be particularly ill-equipped to withstand the novel environmental conditions imposed by intensifying droughts and milder winters. The Appalachian-Northeast Mesic Forest habitat group, dominated by eastern hemlock ( Tsuga canadensis ) and eastern white pine ( Pinus strobus ), is likely particularly vulnerable, as both dominant species are projected to decline due to increasing drought stress and shifting competitive dynamics. In the North-Central Beech - Maple - Basswood Forest, the Driftless Area of Wisconsin, Minnesota, and Iowa may be more vulnerable than more eastern portions of the habitat due to its already drier conditions, with climate change expected to push these communities beyond favorable conditions. Species interactions, including invasive species, pests, and herbivory, are also likely to be reshaped by climate change, compounding stress on habitat groups throughout the Appalachian-Interior-Northeast Mesic Forest. Warmer winters and increased disturbance may facilitate the expansion of invasive species, which outcompete native vegetation and alter ecosystem dynamics. At the same time, pests and pathogens are likely to become more destructive, as milder winters enhance their survival and spread and drought weakens tree defenses. Additionally, rising white-tailed deer ( Odocoileus virginianus ) populations, supported by warmer winters, may shift forest regeneration patterns by selectively browsing on sensitive seedlings and saplings, limiting the recruitment of historically dominant tree species while favoring browse-resistant plants. Collectively, these pressures can drive significant and ongoing ecological transformation in the Appalachian-Interior-Northeast Mesic Forest, highlighting the need for adaptive management strategies to sustain biodiversity and ecosystem function.

Illinois, Indiana, Iowa, Michigan, Minnesota, Miss↗
USGS2025

Effects of climate change on Midwestern ecosystems: Central and Eastern North American Grassland and Shrubland

The Central and Eastern North American Grassland and Shrubland ecosystem may be increasingly shaped by intensifying drought and shifting seasonality. Rising temperatures and more variable precipitation, marked by longer dry spells, are projected to increase evapotranspiration and soil moisture deficits, and yield more frequent drought. At the same time, warming temperatures are projected to advance spring onset and extend the growing season. Drought may alter habitat structure by accelerating soil erosion, disrupting nutrient cycling, increasing physiological stress on plants, and reducing productivity. These changes are expected to shift community composition toward species adapted to water limitation and fluctuating resources, reducing much of the herbaceous cover that characterizes this ecosystem. Seasonal shifts may restructure habitat by altering phenology and f lowering dynamics, potentially increasing productivity but also heightening the risk of late-season frost damage. Community composition is expected to shift toward early-emerging species, particularly coolseason (C3) grasses, and species with phenological flexibility. Altered phenology may also lead to mismatches between plants and pollinators and increase pollinator competition at the beginning and end of the growing season, with potential consequences for reproduction. Although these overarching stressors affect the entire ecosystem, their specific impacts likely vary with local habitat conditions. In the Central and Northern Tallgrass Prairie, which are historically firemaintained habitats dominated by a mix of warm-season (C4) and cool-season (C3) grasses and forbs, climate change may shift community composition by favoring deep-rooted forbs and established shrubs while displacing shallow-rooted species, including many native grasses. These changes, especially in the absence of fire, may promote woody encroachment and drive long-term community reassembly. In the Central Interior Acidic Open Glade and Barrens, characterized by shallow, drought-prone soils, climate change may reinforce xeric assemblages and reduce the abundance of mesic species. In the absence of f ire, shrubs rather than larger woody species, are more likely to increase, as water limitations constrain the establishment of trees. In the Eastern North American Ruderal Meadow and Shrubland, which lack native species richness and structural stability, disturbance-tolerant invaders may increasingly dominate. Drought and earlier springs are expected to reinforce early successional dynamics and further constrain the restoration potential of these already degraded habitats. Across the region, invasive species, herbivory, and microbial and fungal communities are also expected to respond to climate change. Invasive plants with ruderal traits and flexible phenologies are likely to benefit from drought-driven disturbance, post-drought resource pulses, and longer, earlier growing seasons. These species often germinate and flower earlier than natives, gaining priority access to resources as seasonal timing shifts. Herbivory by increasing white-tailed deer (Odocoileus virginianus) populations is expected to intensify, particularly during drought, when plant defenses are weakened, and during extended growing seasons, which prolong forage availability. This selective browsing may contribute to declines in native forbs while indirectly promoting non-native grasses. Microbial and fungal communities, like plant communities, are likely vulnerable to both drought and shifting seasonality. Reduced soil moisture may suppress microbial activity and decomposition, while shifts in fungal community composition, particularly declines in arbuscular mycorrhizal fungi, may impair plant drought tolerance. Adaptation strategies for the Central and Eastern North American Grassland and Shrubland may require managers to anticipate and respond to these changes through both resistance-based approaches, such as restoring fire regimes and reinforcing native species dominance, and acceptance of some potential transitions, such as facilitating drought-tolerant and phenologically flexible species establishment and adjusting fire regimes to align with altered phenology.

Illinois, Indiana, Iowa, Michigan, Minnesota, Miss↗
USGS2023

Potential effects of climate change on Acipenser fulvescens (lake sturgeon)

Acipenser fulvescens (Rafinesque, 1817; lake sturgeon) are the only sturgeon species native to the Great Lakes region and are threatened across most of their range. They are historically vulnerable because of overfishing and habitat fragmentation with the potential for climate change acting as an increasing stressor in the future. Lake sturgeon span multiple habitats during their long lifespans, including high gradient streams, nearshore areas, and deep rivers and lakes. Climate change is projected to strongly affect the suitability of these habitats through increasing precipitation and temperatures and decreasing ice cover and snowmelt. Changes in flow timing and amount can affect movement to spawning and nursery sites, and increased water temperatures are likely to affect species activity patterns, survival, and prey availability. Ultimately, the Great Lakes region is expected to face wide ranging effects from climate change, which may have positive and negative effects on lake sturgeon depending on a variety of factors, including the life stages affected, habitat availability, and interactions with other stressors, but all shifts are likely to affect spawning. Importantly, several areas of further research would be beneficial to understanding the complex effects of climate change on lake sturgeon.

Great Lakes↗
USGS2023

Potential effects of climate change on Emydoidea blandingii (Blanding’s turtle)

Emydoidea blandingii (Holbrook, 1838; Blanding’s turtles) are a species of medium-sized, long-lived, semiaquatic, freshwater turtles with a wide distribution across the northern and eastern United States and southern Canada. They have an annual activity cycle consisting of late autumn and winter overwintering and spring emergence, spring movement and foraging, spring and summer nesting, and summer and autumn foraging and nonnesting movement. In response to changes in average and extreme temperatures, Blanding’s turtles are likely to experience increased physiological stress and reduced reproductive success. Variability in precipitation may affect the availability of freshwater habitats for overwintering, shelter, and feeding; however, projected changes in precipitation vary widely. This analysis presents anticipated climate conditions and effects on the species; the complex life history and expansive geographic range of this species require additional analysis at local scales.

Open-File Report↗
USGS2023

Potential effects of climate change on Ambystoma barbouri (streamside salamander)

Ambystoma barbouri (streamside salamanders) are stream-breeding mole salamanders that rely on seasonally intermittent, fishless streams for egg and larval development but are primarily fossorial as adults. Climate-driven changes are likely to alter streamflow duration, peak, and seasonality within the range of A. barbouri , reducing reproductive habitat and larval survival. Although future changes in precipitation volume within the geographic range of A. barbouri are uncertain, in the next 90 years, increasing temperatures will likely increase potential evapotranspiration. Decreasing ratio of precipitation to potential evapotranspiration will likely shorten flow duration for intermittent streams, potentially causing earlier stream dry downs before larval metamorphosis. Increased temperatures may also shorten developmental periods buffering A. barbouri larvae from the effects of increased stream no-flow days. Additionally, precipitation in the future will increasingly fall in heavy rainfall events. Heavy rain and subsequent flooding during early larval stages may displace A. barbouri larvae from fishless pools into downstream reaches with vertebrate predators that can reduce survival. Finally, agriculture and urban land cover may amplify the stresses of climate change on A. barbouri , altering reproductive habitat and reducing survival of larval, juvenile, and adult life stages.

Illinois, Indiana, Kentucky, Ohio, Tennessee, West↗
USGS2023

Potential effects of climate change on Appalachian stoneflies ( Remenus kirchneri , Acroneuria kosztarabi , and Tallaperla lobata )

Plecoptera (stoneflies) are an order of insects where most species rely on clean, fast-moving freshwater for an aquatic larval stage followed by a short terrestrial adult stage. Most species of Plecoptera seem to be restricted to specific stream types and thermal regimes. Climate-driven changes are likely to alter stream temperatures and flow, resulting in physiological stress, reduced reproductive success, and possibly latitudinal or elevational distribution shifts. This report focuses on climate projections and the resulting ecological effect for three species of Appalachian stoneflies: Remenus kirchneri , Acroneuria kosztarabi , and Tallaperla lobata . Although species-specific information is sparse for these three species, climate studies for other Plecoptera spp. are applicable. In the focal region, temperature is increasing and likely leading to increased stream temperatures. In response, Plecoptera spp. will likely experience physiological stress from increasing metabolic rates and energy demands concurrent with changing food quality and access. Warming temperatures and decreased larval energy stores are likely to contribute to lower adult body size and longevity, thus decreasing reproductive success. Whereas projected changes to precipitation and runoff are less certain, under drier future climate projections, decreased streamflow may further stress larval Plecoptera. Remenus kirchneri , A. kosztarabi , and T. lobata will likely retain stable permanent stream habitats for the analyzed future (2006–99). Changing climate is of particular concern for mountaintop species R. kirchneri and T. lobata because they may be unable to track shifts in suitable climate and habitat.

North Carolina, Tennessee, Virginia↗
USGS2022

Potential effects of climate change on snail kites (Rostrhamus sociabilis plumbeus) in Florida

The snail kite ( Rostrhamus sociabilis plumbeus ), an endangered, wetland-dependent raptor, is highly sensitive to changes in hydrology. Climate-driven changes in water level will likely affect snail kite populations—altering reproductive success and survival rates. Identifying the mechanisms mediating the direct and indirect effects of climate on snail kite populations and the range of future climate conditions is important to the conservation of this species. When water levels are low, snail kite nest initiation and nest success decrease owing to decreased availability of their primary prey applesnails ( Pomacea spp.), unstable nesting sites, and increased predator access. Dry events also lead to decreased adult and juvenile survival. In the next 80 years, temperatures and potential evapotranspiration are projected to increase in central and southern Florida. Although future precipitation volume is more uncertain, increased temperatures and evaporative loss may lead to increased frequency, duration, and severity of low-water events. Additionally, rapidly rising water levels have adverse effects on snail kite reproductive success—destroying nests, preventing access to apple snails, and reducing apple snail productivity. Finally, it is likely that future climate will favor more frequent dry conditions and extreme heavy rainfall events, both of which are directly linked to decreased reproductive success and survival. The potential effects of climate change may be buffered by the availability of alternative prey (non-native applesnails) that are more tolerant of anticipated conditions. In highly controlled southern Florida waterbodies, regional water-management decisions may buffer or exacerbate waterbody accession and recession rates.

Florida↗