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Full-Text Articles in Biology

Drought Legacy Interacts With Wildfire To Alter Soil Microbial Communities In A Mediterranean Climate-Type Forest, Anna J. M. Hopkins, Aaron J. Brace, Jess L. Bruce, J. Hyde, J. B. Fontaine, L. Walden, W. Veber, K. X. Ruthrof Mar 2024

Drought Legacy Interacts With Wildfire To Alter Soil Microbial Communities In A Mediterranean Climate-Type Forest, Anna J. M. Hopkins, Aaron J. Brace, Jess L. Bruce, J. Hyde, J. B. Fontaine, L. Walden, W. Veber, K. X. Ruthrof

Research outputs 2022 to 2026

Mediterranean forest ecosystems will be increasingly affected by hotter drought and more frequent and severe wildfire events in the future. However, little is known about the longer-term responses of these forests to multiple disturbances and the forests' capacity to maintain ecosystem function. This is particularly so for below-ground organisms, which have received less attention than those above-ground, despite their essential contributions to forest function. We investigated rhizosphere microbial communities in a resprouting Eucalyptus marginata forest, southwestern Australia, that had experienced a severe wildfire four years previously, and a hotter drought eight years previously. Our aim was to understand how microbial …


Deconstructing The Mangrove Carbon Cycle: Gains, Transformation, And Losses, M. F. Adame, N. Cormier, P. Taillardat, N. Iram, A. Rovai, T. M. Sloey, E. S. Yando, J. F. Blanco-Libreros, M. Arnaud, T. Jennerjahn, C. E. Lovelock, D. Friess, G. M. S. Reithmaier, C. A. Buelow, S. M. Muhammad-Nor, R. R. Twilley, R. A. Ribeiro Jan 2024

Deconstructing The Mangrove Carbon Cycle: Gains, Transformation, And Losses, M. F. Adame, N. Cormier, P. Taillardat, N. Iram, A. Rovai, T. M. Sloey, E. S. Yando, J. F. Blanco-Libreros, M. Arnaud, T. Jennerjahn, C. E. Lovelock, D. Friess, G. M. S. Reithmaier, C. A. Buelow, S. M. Muhammad-Nor, R. R. Twilley, R. A. Ribeiro

Biological Sciences Faculty Publications

Mangroves are one of the most carbon-dense forests on the Earth and have been highlighted as key ecosystems for climate change mitigation and adaptation. Hundreds of studies have investigated how mangroves fix, transform, store, and export carbon. Here, we review and synthesize the previously known and emerging carbon pathways in mangroves, including gains (woody biomass accumulation, deadwood accumulation, soil carbon sequestration, root and litterfall production), transformations (food web transfer through herbivory, decomposition), and losses (respiration as CO2 and CH4, litterfall export, particulate and dissolved carbon export). We then review the technologies available to measure carbon fluxes in …


The Coastal Monitor: Vol. 10 No. 2, John Tanacredi Ph.D. Oct 2023

The Coastal Monitor: Vol. 10 No. 2, John Tanacredi Ph.D.

The Coastal Monitor

Stephen J. Gould’s prophetic piece, “The Golden Rule: A Proper Scale for Our Environmental Crisis”, noted that, “Patience enjoys a long pedigree of favor”, which he elaborated, “usually involves a deep understanding of the fundamental principle… rarely grasped in daily life – the effects of scale.” Scientists observe changes incessantly, in dimensions and time, from microscopic conditions of cellular biology to the inconceivable distances of galaxies and their influences on Earth.


The Coastal Monitor: Vol. 10 No. 1, John Tanacredi Ph.D. Apr 2023

The Coastal Monitor: Vol. 10 No. 1, John Tanacredi Ph.D.

The Coastal Monitor

New Year’s Day has always been, for me, a time to reflect and project into the near future. Nature’s influence on us all certainly tops my listing with several environmental concerns. For example, the frequency and intensity of hurricanes to Long Island. A decade has passed since Superstorm Sandy re-opened the “Old Inlet” on Long Island which now has mostly naturally closed. So, the new year immediately prompts me to assess the previous year’s Hurricane Ian, a Category 4 system, with winds exceeding 150 mph, which had considerable impact in Florida, and then proceeded north resulting in over 2 inches …


Breeding And Feeding Habitat Selection By An Island Endemic Bird May Increase Its Vulnerability To Climate Change, Paul M. Radley, Eddie J. B. Van Etten, David Blake, Robert A. Davis Nov 2021

Breeding And Feeding Habitat Selection By An Island Endemic Bird May Increase Its Vulnerability To Climate Change, Paul M. Radley, Eddie J. B. Van Etten, David Blake, Robert A. Davis

Research outputs 2014 to 2021

Characterizing patterns of habitat use is an important first step for effective conservation planning. Species restricted to low-lying islands are at greatest risk from climate change-related sea level rise, and requirements for breeding and foraging habitat may determine their risk from tidal inundation. The endangered Micronesian Scrubfowl (Megapodius laperouse senex) is a model species for understanding these impacts. This species faces the cumulative challenges of tourist visitation, invasive species, and rising sea levels, yet little is understood about its habitat use in the Rock Islands Southern Lagoon Conservation Area (RISL) of Palau. We studied the habitat requirements of this mound-nesting …


Diminishing Opportunities For Sustainability Of Coastal Cities In The Anthropocene: A Review, John W. Day, Joel D. Gunn, Joseph Robert Burger Aug 2021

Diminishing Opportunities For Sustainability Of Coastal Cities In The Anthropocene: A Review, John W. Day, Joel D. Gunn, Joseph Robert Burger

Biology Faculty Publications

The world is urbanizing most rapidly in tropical to sub-temperate areas and in coastal zones. Climate change along with other global change forcings will diminish the opportunities for sustainability of cities, especially in coastal areas in low-income countries. Climate forcings include global temperature and heatwave increases that are expanding the equatorial tropical belt, sea-level rise, an increase in the frequency of the most intense tropical cyclones, both increases and decreases in freshwater inputs to coastal zones, and increasingly severe extreme precipitation events, droughts, freshwater shortages, heat waves, and wildfires. Current climate impacts are already strongly influencing natural and human systems. …


Vignette 20: Fraser River Estuary In Need Of Urgent Intensive Care, Laura Kehoe, Tara G. Martin May 2021

Vignette 20: Fraser River Estuary In Need Of Urgent Intensive Care, Laura Kehoe, Tara G. Martin

Institute Publications

The Fraser River is the lifeline of the Salish Sea, influencing its stratification, circulation, and primary productivity. If we do not take strong action to conserve the Fraser River estuary, two-thirds of the species at risk in this region are predicted to have a less than 50% chance of survival. Many of the region's most iconic species could disappear. Conservation action combined with environmental governance is a pathway for a brighter future for the Fraser River and other highly contested regions.


Vignette 02: Lower Trophic Levels In The Salish Sea, Ian Perry May 2021

Vignette 02: Lower Trophic Levels In The Salish Sea, Ian Perry

Institute Publications

Plankton form the base of the pelagic marine food web in the Salish Sea, and are eaten by fishes, marine mammals, and seabirds. Plankton include microscopic plants (phytoplankton) and very small animals (zooplankton). This vignette presents an overview of monitoring observations of phytoplankton and zooplankton distribution and biomass in the Strait of Georgia. Climate change may lead to unusual and unexpected patterns of phytoplankton and zooplankton in the future.


Vignette 04: Olympia Oysters, Jodie Toft, Betsy Peabody May 2021

Vignette 04: Olympia Oysters, Jodie Toft, Betsy Peabody

Institute Publications

Olympia oysters (Ostrea lurida) are our only native oyster species here in the Salish Sea. Olympia oysters once covered an estimated 13-26% of the intertidal area in Puget Sound, mostly near the heads of inlets. A combination of overharvest, pollution, and habitat loss reduced the current population to less than 4% of historic numbers, though sparse numbers of Olympia oysters can still be found throughout most of their historic distribution. Looking to the future, as our region’s marine waters experience effects of climate change and ocean acidification (OA), native species such as the Olympia oyster may prove to …


Vignette 17: Salish Sea Jellyfish, Correigh Greene May 2021

Vignette 17: Salish Sea Jellyfish, Correigh Greene

Institute Publications

The Salish Sea is home to a diverse community of gelatinous zooplankton (or "jellies"). In their adult forms, jellies comprise a relatively large proportion of biomass in the Salish Sea. Questions regarding jellyfish abundance and climate variation in the Salish Sea have been difficult to address, in part because of a lack of consistent monitoring. Research presented in this vignette suggests that jellyfish are sensitive to climate signals like marine water temperatures, but do not appear to be systematically increasing in abundance over time. Due to advances in modeling, we may gain a better perspective on the roles jellies play …


Vignette 21: How Ecological Time-Series Inform Response To Stressors, Jackson W.F. Chu May 2021

Vignette 21: How Ecological Time-Series Inform Response To Stressors, Jackson W.F. Chu

Institute Publications

An important part of biodiversity monitoring includes assessing the differences in vulnerability across parts of an ecosystem. Hypoxia is one of the big three climate- related stressors causing biodiversity loss in the oceans. As the ocean warms, its capacity to hold oxygen becomes reduced. At the same time, concurrent shifts in circulation result in changes to how oxygen gets transported from the surface (where oxygen dissolves into the ocean) to the seafloor and from offshore to inshore areas. When a habitat experiences a substantial drop in oxygen, below the point needed to sustain everyday life, animals respond by migrating away, …


Vignette 23: Indigenous Management Systems Can Promote More Sustainable Salmon Fisheries In The Salish Sea, William I. Atlas, Natalie C. Ban, Jonathan W. Moore, Adrian M. Tuohy, Spencer Greening, Andrea J. Reid, Nicole Morven, Elroy White, William G. Housty, Jess A. Housty, Christina N. Service, Larry Greba, Sam Harrison, Katherine Ir Butts, Elissa Sweeney-Bergen, Donna Macintyre, Matthew R. Sloat, Katrina Connors May 2021

Vignette 23: Indigenous Management Systems Can Promote More Sustainable Salmon Fisheries In The Salish Sea, William I. Atlas, Natalie C. Ban, Jonathan W. Moore, Adrian M. Tuohy, Spencer Greening, Andrea J. Reid, Nicole Morven, Elroy White, William G. Housty, Jess A. Housty, Christina N. Service, Larry Greba, Sam Harrison, Katherine Ir Butts, Elissa Sweeney-Bergen, Donna Macintyre, Matthew R. Sloat, Katrina Connors

Institute Publications

Indigenous peoples of the Northern Pacific Rim have harvested salmon for more than 10,000 years, and Pacific salmon (Oncorhynchus spp.) form the foundation of social-ecological systems encompassing communities from California to Kamchatka and Northern Japan. Through continuous placed-based interdependence with salmon, Indigenous societies formed deliberate and well-honed systems of salmon management. These systems promoted the sustained productivity of salmon fisheries. In Canada and the United States, Indigenous sovereignty and resource stewardship were forcibly disrupted by colonial government authority. Despite the destructive impacts of colonization, Indigenous culture and knowledge are resurgent in Canada and the United States. Indigenous fishing technologies and …


Vignette 14: Eelgrass Wasting Disease, Olivia Graham, Morgan Eisenlord, Drew Harvell May 2021

Vignette 14: Eelgrass Wasting Disease, Olivia Graham, Morgan Eisenlord, Drew Harvell

Institute Publications

Rising seawater temperatures can increase the risk of disease outbreaks in many taxa. Pathogens are potentially the ultimate keystone species in that their small biomass can have massive impacts that ripple through ecosystems. Disease outbreaks can be particularly damaging when they affect ecosystem engineers, such as seagrasses. Outbreaks of wasting disease in seagrasses are one of a myriad of stressors associated with declining temperate and tropical seagrass meadows around the globe. Levels of eelgrass wasting disease are high in the San Juan Islands and Puget Sound. These increasing levels of disease are a threat to sustainability of eelgrass meadows, our …


Vignette 16: Vulnerability And Climate Change Adaptation, Northwest Indian Fisheries Commission, Jamestown S'Klallam Tribe May 2021

Vignette 16: Vulnerability And Climate Change Adaptation, Northwest Indian Fisheries Commission, Jamestown S'Klallam Tribe

Institute Publications

The 2013 Jamestown Climate Vulnerability Assessment and Adaptation Plan provides an assessment of vulnerabilities of tribal resources to the negative impacts of climate change. The plan also identifies adaptation measures that the tribe is working to complete. Sea level rise, ocean acidification and climate models show potential for increased risks to critical habitats, tribal infrastructure and tribal health. As one of the first tribes in western Washington to complete a climate adaptation plan and vulnerability assessment, the Jamestown S’Klallam Tribe has identified and prioritized areas where changing climate conditions will leave tribal resources, infrastructure, economy and health most vulnerable, Climate …


Vignette 15: Eelgrass Variations Ties To Sea Level Variations, Ronald Thom May 2021

Vignette 15: Eelgrass Variations Ties To Sea Level Variations, Ronald Thom

Institute Publications

This vignette shares an overview of the process and results of a long-term eelgrass monitoring effort at the mouth of Sequim Bay. Coupling these local long-term findings with research and monitoring across the Salish Sea and the globe will help better understand the longer-term effects of global warming and perhaps other human and natural-derived pressures on coastal ecosystems, and provide clues on how to make these systems more resilient to pressures.


Vignette 13: The Salish Sea Model, Tarang Khangaonkar P.E. May 2021

Vignette 13: The Salish Sea Model, Tarang Khangaonkar P.E.

Institute Publications

Given numerous concerns related to the health of the ecosystem and the possibility of anthropogenic impacts—from population growth to climate impacts, such as sea level rise—scientists, engineers, and planners seek an improved basic understanding of the biophysical behavior of the Salish Sea. The Salish Sea Model (SSM) development was motivated by this urgent need for a comprehensive predictive model that could diagnose water quality issues and concerns and serve as a planning tool in support of Puget Sound restoration efforts. The SSM was developed by the Pacific Northwest National Laboratory in collaboration with the Washington State Department of Ecology (Ecology) …


Variation In Coral Thermotolerance Across A Pollution Gradient Erodes As Coral Symbionts Shift To More Heat-Tolerant Genera, Melissa S. Naugle, Thomas A. Oliver, Daniel J. Barshis, Ruth D. Gates, Cheryl A. Logan Jan 2021

Variation In Coral Thermotolerance Across A Pollution Gradient Erodes As Coral Symbionts Shift To More Heat-Tolerant Genera, Melissa S. Naugle, Thomas A. Oliver, Daniel J. Barshis, Ruth D. Gates, Cheryl A. Logan

Biological Sciences Faculty Publications

Phenotypic plasticity is one mechanism whereby species may cope with stressful environmental changes associated with climate change. Reef building corals present a good model for studying phenotypic plasticity because they have experienced rapid climate-driven declines in recent decades (within a single generation of many corals), often with differential survival among individuals during heat stress. Underlying differences in thermotolerance may be driven by differences in baseline levels of environmental stress, including pollution stress. To examine this possibility, acute heat stress experiments were conducted on Acropora hyacinthus from 10 sites around Tutuila, American Samoa with differing nutrient pollution impact. A threshold-based heat …


Breeding And Feeding Habitat Selection By An Island Endemic Bird May Increase Its Vulnerability To Climate Change [Dataset], Paul Radley, Eddie Van Etten, David Blake, Robert Davis Jan 2021

Breeding And Feeding Habitat Selection By An Island Endemic Bird May Increase Its Vulnerability To Climate Change [Dataset], Paul Radley, Eddie Van Etten, David Blake, Robert Davis

Research Datasets

Characterising patterns of habitat use is an important first step for effective conservation planning. Species restricted to low-lying islands are at greatest risk from climate change-related sea level rise, and requirements for breeding and foraging habitat may determine their risk from tidal inundation. The endangered Micronesian Scrubfowl (Megapodius laperouse senex) is a model species for understanding these impacts. This species faces the cumulative challenges of tourist visitation, invasive species, and rising sea levels, yet little is understood about its habitat use in the Rock Islands Southern Lagoon Conservation Area (RISL) of Palau. We studied the habitat requirements of …


No Evidence Of Fine Scale Thermal Adaption In Green Turtles, Taylor Apter Jan 2020

No Evidence Of Fine Scale Thermal Adaption In Green Turtles, Taylor Apter

Scientific Communication News

No abstract provided.


Effects Of Increased Precipitation On The Life History Of Spring- And Autumn-Germinated Plants Of The Cold Desert Annual Erodium Oxyrhynchum (Geraniaceae), Yanfeng Chen, Xiang Shi, Lingwei Zhang, Jerry M. Baskin, Carol C. Baskin, Huiliang Liu, Daoyuan Zhang Apr 2019

Effects Of Increased Precipitation On The Life History Of Spring- And Autumn-Germinated Plants Of The Cold Desert Annual Erodium Oxyrhynchum (Geraniaceae), Yanfeng Chen, Xiang Shi, Lingwei Zhang, Jerry M. Baskin, Carol C. Baskin, Huiliang Liu, Daoyuan Zhang

Biology Faculty Publications

Future increased precipitation in cold desert ecosystems may impact annual/ephemeral plant species that germinate in both spring and autumn. Our primary aim was to compare the life history characteristics of plants from spring-germinating (SG) and autumn-germinating (AG) seeds of Erodium oxyrhynchum. Plants in field plots with simulated increases in precipitation of 0, 30 and 50 % in spring and summer were monitored to determine seedling survival, phenology, plant size, seed production and biomass accumulation and allocation. Germination characteristics were determined in the laboratory for seeds produced by plants in all increased precipitation treatments. Increased precipitation in spring significantly improved survival …


Seed Germination Responses To Seasonal Temperature And Drought Stress Are Species‐Specific But Not Related To Seed Size In A Desert Steppe: Implications For Effect Of Climate Change On Community Structure, Fengyan Yi, Zhaoren Wang, Carol C. Baskin, Jerry M. Baskin, Ruhan Ye, Hailian Sun, Yuanyuan Zhang, Xuehua Ye, Guofang Liu, Xuejun Yang, Zhenying Huang Feb 2019

Seed Germination Responses To Seasonal Temperature And Drought Stress Are Species‐Specific But Not Related To Seed Size In A Desert Steppe: Implications For Effect Of Climate Change On Community Structure, Fengyan Yi, Zhaoren Wang, Carol C. Baskin, Jerry M. Baskin, Ruhan Ye, Hailian Sun, Yuanyuan Zhang, Xuehua Ye, Guofang Liu, Xuejun Yang, Zhenying Huang

Biology Faculty Publications

Investigating how seed germination of multiple species in an ecosystem responds to environmental conditions is crucial for understanding the mechanisms for community structure and biodiversity maintenance. However, knowledge of seed germination response of species to environmental conditions is still scarce at the community level. We hypothesized that responses of seed germination to environmental conditions differ among species at the community level, and that germination response is not correlated with seed size. To test this hypothesis, we determined the response of seed germination of 20 common species in the Siziwang Desert Steppe, China, to seasonal temperature regimes (representing April, May, June, …


Riparian Vegetation, Colorado River, And Climate: Five Decades Of Spatiotemporal Dynamics In The Grand Canyon With River Regulation, Joel B. Sankey, Barbara Ralston, Paul E. Grams, John C. Schmidt, Laura E. Cagney Aug 2015

Riparian Vegetation, Colorado River, And Climate: Five Decades Of Spatiotemporal Dynamics In The Grand Canyon With River Regulation, Joel B. Sankey, Barbara Ralston, Paul E. Grams, John C. Schmidt, Laura E. Cagney

Watershed Sciences Faculty Publications

Documentation of the interacting effects of river regulation and climate on riparian vegetation has typically been limited to small segments of rivers or focused on individual plant species. We examine spatiotemporal variability in riparian vegetation for the Colorado River in Grand Canyon relative to river regulation and climate, over the five decades since completion of the upstream Glen Canyon Dam in 1963. Long-term changes along this highly modified, large segment of the river provide insights for management of similar riparian ecosystems around the world. We analyze vegetation extent based on maps and imagery from eight dates between 1965 and 2009, …


Warming, Competition, And Bromus Tectorum Population Growth Across An Elevation Gradient, Aldo Compagnoni, Peter B. Adler Sep 2014

Warming, Competition, And Bromus Tectorum Population Growth Across An Elevation Gradient, Aldo Compagnoni, Peter B. Adler

Green Canyon Environmental Research Area, Logan Utah

Cheatgrass (Bromus tectorum) is one of the most problematic invasive plant species in North America and climate change threatens to exacerbate its impacts. We conducted a two‐year field experiment to test the effect of warming, competition, and seed source on cheatgrass performance across an elevation gradient in northern Utah. We hypothesized that warming would increase cheatgrass performance, but that warming effects would be limited by competing vegetation and by local adaptation of cheatgrass seed sources. The warming treatment relied on open top chambers, we removed vegetation to assess the effect of competition from neighboring vegetation, and we reciprocally …


Warming, Soil Moisture, And Loss Of Snow Increase Bromus Tectorum’S Population Growth Rate, Aldo Compagnoni, Peter B. Adler Jan 2014

Warming, Soil Moisture, And Loss Of Snow Increase Bromus Tectorum’S Population Growth Rate, Aldo Compagnoni, Peter B. Adler

Green Canyon Environmental Research Area, Logan Utah

Climate change threatens to exacerbate the impacts of invasive species. In temperate ecosystems, direct effects of warming may be compounded by dramatic reductions in winter snow cover. Cheatgrass (Bromus tectorum) is arguably the most destructive biological invader in basins of the North American Intermountain West, and warming could increase its performance through direct effects on demographic rates or through indirect effects mediated by loss of snow. We conducted a two-year experimental manipulation of temperature and snow pack to test whether 1) warming increases cheatgrass population growth rate and 2) reduced snow cover contributes to cheatgrass’ positive response to …


Synergistic Effects Of The Invasive Chinese Tallow (Triadica Sebifera) And Climate Change On Aquatic Amphibian Survival, Daniel Saenz, Erin M. Fucik, Matthew Kwiatkowski Jan 2013

Synergistic Effects Of The Invasive Chinese Tallow (Triadica Sebifera) And Climate Change On Aquatic Amphibian Survival, Daniel Saenz, Erin M. Fucik, Matthew Kwiatkowski

Faculty Publications

Changes in climate and the introduction of invasive species are two major stressors to amphibians, although little is known about the interaction between these two factors with regard to impacts on amphibians. We focused our study on an invasive tree species, the Chinese tallow (Triadica sebifera), that annually sheds its leaves and produces leaf litter that is known to negatively impact aquatic amphibian survival. The purpose of our research was to determine whether the timing of leaf fall from Chinese tallow and the timing of amphibian breeding (determined by weather) influence survival of amphibian larvae. We simulated a …


Recent Advances In The Climate Change Biology Literature: Describing The Whole Elephant, A. Townsend Peterson, Shaily Menon, Xingong Li Jun 2010

Recent Advances In The Climate Change Biology Literature: Describing The Whole Elephant, A. Townsend Peterson, Shaily Menon, Xingong Li

Peer Reviewed Publications

Climate change biology is seeing a wave of new contributions, which are reviewed herein. Contributions treat shifts in phenology and distribution, and both document past and forecast future effects. However, many of the current wave of contributions are observational and correlational, and few are experimental in nature, and too often a conceptual framework in which to contextualize the results is lacking. An additional gap is the lack of effective cross-linking among areas of research, for example, connection of sea-level rise and climate change implications for distributions of species, or evolutionary adaptation studies with distributional shift studies. Although numerous important contributions …


Sustainability In A Time Of Climate Change: Developing An Intensive Research Framework For The Platte River Basin And The High Plains Proceedings From The 2008 Climate Change Workshop, Monica Norby, Ashley Washburn Jan 2008

Sustainability In A Time Of Climate Change: Developing An Intensive Research Framework For The Platte River Basin And The High Plains Proceedings From The 2008 Climate Change Workshop, Monica Norby, Ashley Washburn

Office of Research and Economic Development: Publications

Proceedings from the 2008 Climate change Workshop, Nebraska Sandhills, May 19-22, 2008. Hosted by the University of Nebraska–Lincoln and the U.S. Geological Survey


Environmental Stress Effects On Vigor, Mortality, And Growth In Northern Hardwood Forests Along A Pollution-Climate Gradient, Neil W. Macdonald, John A. Witter, David R. Reed, Andrew J. Burton, Kurt S. Pregitzer, Hal O. Liechty Jan 1998

Environmental Stress Effects On Vigor, Mortality, And Growth In Northern Hardwood Forests Along A Pollution-Climate Gradient, Neil W. Macdonald, John A. Witter, David R. Reed, Andrew J. Burton, Kurt S. Pregitzer, Hal O. Liechty

Peer Reviewed Publications

Concern exists over the effects of interacting environmental stresses on the ecological integrity of temperate forests. Coincidence of sensitivity to drought, increasing occurrence of defoliation, and elevated pollutant deposition has produced speculation that northern hardwood forests may be susceptible to the increased climatic stresses projected for the Great Lakes region. The objective of our study was to examine relationships among environmental stress factors, vigor, mortality, and growth in northern hardwood forests located along a pollution-climate gradient in the Great Lakes region. Between 1987 and 1993, we quantified climatic variables, pollutant deposition, insect defoliation, and tree vigor and growth at five …