From Drowning Coastal Marshes and Punk Ducks to Soil Crusts
The 2010 Ecological Society of America conference is in Pittsburg, Penn., from Aug. 1 to Aug. 6. This year’s theme is Global Warming: The Legacy of Our Past, the Challenge for Our Future.
Drowning marshes: How High Can the Seas Rise Before Wetlands Go Under? Habitat for many commercially important fish and shellfish populations, recreational fishing, and unique ways of living, coastal wetlands are among the most valuable ecosystems on earth, and of all the threats they face, sea-level rise is one of the most critical. Already, marshes in many parts of the world seem to be drowning as sea levels steadily increase. USGS scientists Matthew L. Kirwan and Glenn Guntenspergen studied just how high sea level can rise before coastal wetlands are likely to disappear. Their research, based on model experiments, show that the rate of sea-level rise and the amount of sediment available will be the most important determining factors in the survival of coastal wetlands. If the water rises too fast and with too little sediment deposition, the wetlands worldwide will likely drown by the end of the 21st century. If sea levels rise more slowly and with a higher amount of sediment deposition associated with the rise, then the coastal wetlands will be more likely to survive. This presentation, Threshold sea level rise rates for wetland survival: limits to ecogeomorphic feedbacks, will be presented on Aug. 3 at 8:40 a.m. in Room 301-302. Contact Matthew Kirwan at mkirwan@usgs.gov or Glenn Guntenspergen at 218-343-6107 or glenn_guntenspergen@usgs.gov.
Climate Change Likely to Harm Vital Soil Crusts in the Colorado Plateau: Predicted climate change in the Colorado Plateau will likely strongly alter soil crust composition, an essential player in the structure and function of arid and semi-arid ecosystems, according to preliminary USGS research. These communities, composed primarily of cyanobacteria, algae, lichens and mosses, can completely cover plant interspaces in undisturbed areas and make up 70 percent or more of the living ground cover. Biological soil crusts fix atmospheric nitrogen and carbon dioxide and serve as important sources of fixed carbon and nitrogen for these sparsely vegetated systems. USGS scientists conducted a field study to experimentally simulate the more extreme scenario of predicted changes in precipitation and examined the combined effects of pulsing summer precipitation and warming on soils and biological soil crusts. Preliminary results showed that warming alone did not seem to affect soil crusts, but in watered plots a dramatic reduction in soil crusts and mosses occurred, along with lowered amounts of soil carbon, nitrogen and soil phosphorous. These preliminary results suggest that changes to precipitation patterns projected for the Colorado Plateau will likely strongly affect biological soil crust composition, especially moss cover, with important consequences for soil nutrient cycling. This ongoing research project, Responses of biological soil crusts in arid and semi-arid ecosystems to predicted climate change, will be presented on Aug. 3 at 2:10 p.m. Contact Tamara Zelikova at 435-719-2350 or jzelikova@usgs.gov.
Alien Invaders Leading to More Worldwide Flora Homogenization: Although at regional levels, invasive plants are often the most widely distributed plant species, on a global level, invasive patterns are quite asymmetric, according to a USGS study. The study found that more than half of the widely distributed species in the United States were alien, whereas Europe had almost no alien species on its top 120 list of plant species. Alien plant species were also common on the top 120 list for New South Wales (43 percent), Chile (34 percent), Argentina (30 percent), and the Republic of South Africa (22 percent). In Europe, only 2 percent of the most common species are alien, whereas in the United States it is 40 percent. In all countries, however, the alien species present were equally or more widely distributed in comparison to native species on the lists. These widespread alien species contribute to the continued homogenization of global flora. This research, Widespread plant species: Natives vs. aliens in our changing world, will be presented on Aug. 4 at 10:30 a.m. in Rooms 315-16. Contact Thomas J. Stohlgren at 970-491-1980 or stohlgrent@usgs.gov.
Invasive Cheatgrass Cheating Sagebrush of its Root Growth: Although it may be best known from the series Rawhide, sagebrush plays a vital role in Western habitats and for many animal species. Yet sagebrush habitat itself is disappearing rapidly, threatened by land-use alteration and rapidly spreading invasive species, such as cheatgrass. A recent USGS laboratory study found that sagebrush roots appear to grow less quickly in the presence of invasive cheatgrass than when grown with other sagebrush individuals. Yet the study also indicated that sagebrush grown in the presence of activated charcoal, which is found in soils after fires, might be better able to compete with cheatgrass. Further investigations are ongoing; these research results will help provide managers with tools to restore and manage the important sagebrush ecosystem. This research, Effects of root interactions on Wyoming big sagebrush root growth, will be presented on Aug. 5 at 3:20 p.m. in Room COS 11-6. Contact Upekala C. Wijayratne at 541-737-2324, uwijayratne@usgs.gov.
Punk Ducks: Migration Patterns of Elusive Sea ducks: Sea ducks are the least-studied and most bizarrely decorated (think punk ducks) group of ducks, yet most sea duck populations appear to be declining, and two are listed as threatened. USGS scientist Elise Zipkin and colleagues looked at 5 of the 12 sea duck species that winter off the eastern coast of the United States and Canada to help shed light on the ecology and migration patterns of these species: long-tailed ducks, common eiders, and black, surf, and white-winged scoters. While each species responded differently to local environmental characteristics, all five species were significantly affected by the North Atlantic Oscillation, an alternating fluctuation of sea surface pressure that strongly affects the weather patterns in the eastern part of North America. In addition, all species showed some level of site fidelity or loyalty among the 10 ten years of the study and exhibited significant responses to latitudinal gradients suggesting an important, yet diverse, southern boundary for each species. This information is critical to help unravel the complex relationship between the North Atlantic Oscillation, sea surface temperature, and local sea duck abundances, and should help assess the effects of climate change on these remarkable birds. Since current projections suggest that the NAO and sea surface temperature may alter in response to climate change, research that helps clarify the variability in species’ responses to large- scale climatic variables will help with their future protection. This research, Distribution patterns of wintering sea ducks in relation to the North Atlantic Oscillation and implications for a changing climate, will be presented on Aug. 4 at 1:50 p.m. in Room 310-311. Contact Elise Zipkin at 301-497-5810 or ezipkin@usgs.gov.
Wildlife Response to Seasonal Climate Change: Phenology Network Adds Animals: Like to watch bees, bats, butterflies or birds? This year, the USA-National Phenology Network (USA-NPN) is adding about 160 animal species to its existing program of 252 plant species, which means that professional and citizen-scientists will be able to record information about the seasonal patterns of these species to help researchers understand how seasonal patterns of plants and animals are being altered by climate change. The USA-NPN connects backyard and amateur naturalists, resource managers, scientists and policy makers in a collective effort toward understanding the phenology — or seasonal patterns — of plants and animals and the interaction of these phenologies with natural ecological systems. The collected data can be used for remote sensing studies, analysis of species response to environmental change, and to understand linkages between biological and hydrological cycles, among other applications. Phenology data are also important for managing human health risks, such as pollen release; the timing of agricultural planting, pest treatments and harvesting; and wildlife and fisheries management. Ultimately, a national phenology database will provide important input for decisions needed for societal adaptation to climate change. This poster presentation, An integrated plant and animal phenology monitoring system: a new national program for reporting contemporary phenology data, will be shown in Exhibit Hall A on Aug. 2 from 4:30 to 6:30 p.m. Contact Kathryn Thomas at the poster site or at 570-670-5534 or at Kathryn_A_Thomas@usgs.gov.
Oak Savannas: Where East Meets West: The oak savannas of the Midwest are the transition landscape between vast western grasslands and the great forests of the East. Historically, these savannas covered millions of acres but are today among the most endangered ecosystems on the planet. Until recently, managers had little information about the value of these oak savannas for plants and animals. A USGS study by Ralph Grundel and Noel B. Pavlovic found that while some animals and plants occupied all of habitats across this transitional landscape – from grasslands to forests – at about the same rate, others definitely had strong preferences for either grasslands or forest habitats. However, comparatively few plants and animals had strong preferences for the oak savannas, which suggests that plants and animals tend to use savannas more as an ecotonal – or transitional habitat – rather than one whose characteristics strongly differentiate it from other habitats along the grassland-forest continuum. In addition, the two found that the diversity of the groundlayer in oak savannas increases as fire frequency increases, canopy cover decreases, light increases, and soil productivity increases. Patterns of groundlayer composition suggest that climate change will shift the important and diverse groundlayer composition relative to how much it alters tree canopy cover through changes in fire regime and moisture gradients through increased or decreased seasonal rain or snow. This information will help resource managers plan effective management and restoration activities and to plan for future climate change strategies. The research on Midwest oak savannas – unique or ecotonal? will be presented on Aug. 3 at 8:40 a.m. in Rooms 306-307. The research on Determinants of oak savanna ground layer composition and richness will be in the same room on Aug. 3 at 9:50 a.m. Contact Ralph Grundel at 219-926-8336 x422 or at rgrundel@usgs.gov or contact Noel Pavlovic at 219-926-8336 x428 or at npavlovic@usgs.gov.
Fiery Changes in Southern California Fire Occurrence: USGS researchers found that southern California is the only part of the state that has experienced significant increases in wildfires over the last five decades. Analysis shows that this increase is linked to the rise in atmospheric temperature. Past studies suggest that wildfire activity has increased throughout the western United States. USGS researchers wanted to know whether this pattern has region-specific variations and causes. For the analysis, they divided California into five climate zones and looked at how number of wildfires and area burned have changed over the past 49 years. But this study did not find statewide increases in wildfires. Only southern California experienced increases in fires and area burned. Curiously, the increases are not linked to that region’s enormous change in population growth. However, for northern California, analysis shows that wildfire trends have links to population trends. This research gives new perspectives on wildfire trends in California. The results will inform urban and natural resource planners on their long-term outlook on wildfire management. This research will be presented on Aug. 5 at 2:10 p.m. in Room 301-302. Contact: Dr. Jon Keeley at 559-79-8985 or at jon_keeley@usgs.gov.
Mountaintop Removal for Coal Mining Harms Forest Songbirds: Mountaintop removal for coal mining affects diversity and abundance of songbird species differently in reclaimed areas and in intact and fragmented forests, according to a USGS study. Mountaintop removal converts a landscape of predominately mature deciduous forest to one containing reclaimed grassland and scrubland habitats that surround remnant forest patches. USGS researcher Petra Wood found that songbird richness and abundance were highest in reclaimed scrublands and lowest in reclaimed grasslands. Richness and abundance did not differ between intact and fragmented forests because the increased abundance of species that can live on the edges of fragmented and intact forests balanced the loss of species dependent on interior forests. Grassland, edge, and interior-edge songbirds were more abundant on the post-mining landscape and forest-interior species were more abundant in intact than fragmented forest. The research specifically examined cerulean warblers because southern West Virginia lies within the core range of this at-risk species. These warblers appear to be negatively affected from loss of forested habitat, particularly ridgetops where they occur in greater densities, and from degradation of remaining forests, as evidenced by lower territory density in fragmented forests and lower territory density and abundance closer to mine edges. The severity of habitat loss and fragmentation for this species and other forest-dwelling birds will depend on whether mountaintop removal areas are reforested, which may help lessen the effects of forest loss and fragmentation. Non-timber post-mining land uses such as grazing or development will result in permanent fragmentation of forest habitats. This research, Effects of MTR on avian diversity and abundance, cerulean warblers as a case study, will be presented on Tuesday, Aug. 3 at 9:10 a.m. in Blrm A. For more information, contact Petra Wood at 304-293-5090 or atpbwood@usgs.gov.
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