Page updated 5 December 2005

Workshop Home

List of Participants

Newsroom

Background

Program and Events

Agenda

Abstracts

Presentations

Call for Contributed Presentations

Sponsors

Registration and Rates

General Information

Now available in PDF format: Abstract Book [7.4 Mb] (posted 10 November 2005)

Abstracts for Posters

Ecosystems (P-EC)

Sub-Theme 1: Observations & Applications

P-EC1.1

Influence of Climate Variability on Regional Vegetation and Water Cycle
over the East Coast of the United States

Donglian Sun, George Mason University, dsun@gmu.edu

Menas Kafatos, George Mason University

Ruixin Yang, George Mason University

The El Niño/Southern Oscillation (ENSO) has shown its impact on numerous land, ocean and climatic parameters in different parts of the world. The present paper discusses the impact of ENSO on regional vegetation and hydrology over the US East Coast. The Normalized Difference Vegetation Index (NDVI) derived from the AVHRR has been found to decrease 7-10% over the East Coast region during the El Niño years (1982-83, 1987, 1992, and 1994), which is supported by the decrease of evapotranspiration at the same period. During the last two decades, the general trend of normalized NDVI over the US East Coast region has been increased at the rate of 3.72%/decade, while the evapotranspiration has been decreased at a rate of 0.479 mm/decade. At the same time, the regional water cycle is found enhanced, and the ENSO has important impacts on regional hydrological cycle. Increasing of both negative Southern Oscillation Index (SOI) (El Niño) and positive SOI index (La Niña) are responsible for the decrease in NDVI. The present results show that both El Niño and La Niña years affect the regional vegetation growth significantly.

P-EC1.2

Satellite-derived MODIS Vegetation Attributes: Indicators of Climatic Effects
on Biodiversity and Productivity Across the U.S.A.?

Nightingale, J.M., College of Forestry, Oregon State University, Corvallis, Oregon 97331, USA, Joanne.Nightingale@ubc.ca

Coops, N.C., Integrated Remote Sensing Studio, Department of Forest Resource Management, University of British Columbia Vancouver, Canada V6T 1Z4

Waring, R.H., College of Forestry, Oregon State University, Corvallis, Oregon 97331, USA

Fan, W., Natural Sciences & Mathematics, The Richard Stockton College of New Jersey, Pomona, New Jersey, USA 08240

Our general tenet is that modeled and observed responses of terrestrial vegetation to climatic variation must be expressed and measured in a standardized, readily interpretable manner to be useful to policy makers and justifiable to the public. Long before successional alterations in vegetation composition are noted, climatic variation induces changes in the initiation, duration, and effectiveness of the growing season. A recently developed Growing Season Index (GSI) shows the ability to estimate seasonal vegetation activity (net CO₂ flux) at a monthly time-scale across a full range of
vegetation types within the contiguous USA. The computed GSI agreed (R² ≥ 0.8) with the monthly patterns exhibited by the MODIS Enhanced Vegetation Index (EVI) in seven level II EPA defined ecoregions dominated by forest (mixed, deciduous and evergreen) vegetation. Relationships between monthly GSI and the EVI were not as robust (R² ≥ 0.5) for the remaining 14 ecoregions with less developed canopies, such as those dominated by grassland, savannas and shrublands. Growing season photosynthetic activity was also well characterized at monthly intervals using MODIS EVI data. For dominant vegetation types within each ecoregion there was a significant positive linear relationship (R² = 0.72) between annual maximum mean GSI, representing potential productivity, and maximum MODIS EVI. With the availability of MODIS-derived products displaying variation in vegetation activity, we advocate that this globally available technology be considered as a general tool to evaluate the extent that regional changes in climate affect current vegetation. Indirectly, the EVI may have additional value to indicate changes in biodiversity as it accounts for 68% of observed variation in tree richness patterns across 65 forested level III EPA defined ecoregions across the United States.

[Poster PDF]

P-EC1.3

Altered Climate and Ecosystem Response: The Long-Term Ecological Research Program (LTER)

Jim Gosz, University of New Mexico, jgosz@sevilleta.unm.edu

Mark Williams, University of Colorado, markw@snobear.colorado.edu

Deb Peters, ARS-USDA

Alan Knapp, Colorado State University

Here we provide examples from the LTER network on the current state of observations, modeling, and research on altered climate and ecosystem response, with an emphasis on providing input to decision makers. The National Science Foundation established the LTER program in 1980 to support research on long-term ecological phenomena in the United States. Currently the 26 LTER Sites represent diverse ecosystems and research emphases, involving more than 1,800 scientists and students investigating ecological processes over long temporal and broad spatial scales. We build on the mission of the LTER program to provide policy makers and society with the knowledge and predictive understanding necessary to conserve, protect, and manage the nation's ecosystems, their biodiversity, and the services they provide. We provide example applications of scientific information to support decision making, including: (a) changes in climate and carbon sequestration in the Great Plains (Konza LTER) and western high-elevation forests (NWT LTER); and (b) potential for increased desertification at the Jornada LTER site in the southwestern U.S. Within these examples, we stress new methods for communicating scientific information, including incorporation of information about levels of confidence and uncertainty in decision making, and methods and metrics for evaluating outcomes.

P-EC1.4

Climate LINKages of UPland—Lowland Environments (LINKUP)

Henry Diaz, NOAA/OAR/CDC, Henry.F.Diaz@noaa.gov

A conceptual view has emerged in climate and global change science of the interconnectedness between natural ecosystems and the larger environment within which it operates. While the concept is sometimes applied to natural living systems that exclude human beings, the impact of human activities, which affect the operation of physical and ecological systems on a variety of space and time scales, must be included in the development of future
scenarios of the impacts of climate change.

The western portions of the United States have experienced tremendous population growth, which is changing the fabric of the urban and rural landscapes across the region. The physical chord that connects the entire palimpsest of western history to the present time is water—its scarcity on the landscape and the riparian corridors that connect upland and lowland environments. In effect, the streams, which begin high in the North American Cordillera and bring water to the densely populated western "lowlands," can be thought of as a vast "vascular system" pumping the lifeblood of the region.

In the last 30 years changes in the climate of the region already have brought about inter alia, measurable changes in plant phenology, in the seasonal cycle of snowmelt and streamflow, in the rate of growth and disturbance of high elevation forest conifers, and in the drought cycles that are an integral part of the growth dynamics of grasslands and open woodlands in the West. It is the purpose of this presentation to consider some of the implications of these changes in the climate of the western United States, paying particular attention to impacts that are already being manifested in the landscape and climate of the region: from forested and meadowed uplands, through the lower border grasslands and riverine systems that connect them, to some hyper-arid areas in the lower reaches. The presentation will focus on an assessment of the capacity of the current climate observing system to allow decision makers to recognize and foresee future changes in water resources due to changes in the hydroclimatology of the region, and to inform possible preparations for future water shortages. CCSP Themes: Water (drought, water supply), ecosystems, energy (hydropower).

[Poster PDF]