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Simulating soil organic nitrogen and grazing effects on arctic tundra vegetation dynamics on the Yamal Peninsula, Russia
Yu Q, Epstein HE, Walker DA
Land Cover, Land Use Change Spring Science Team M, Bethesda, MD, 31 March - 2 April 2009
Decadal changes of phenological patterns over Arctic tundra biome
Jia GJ, Epstein HE, Walker DA, Hu Y, Wang H
Land Cover, Land Use Change Spring Science Team M, Bethesda, MD, 31 March - 2 April 2009
Spatiotemporal trends in tree and tall shrub cover in the circumpolar Arctic: evidence from repeat ground photographs and 1960s satellite imagery
Frost GV, Epstein HE, Jorgenson MT
Land Cover, Land Use Change Spring Science Team M, Bethesda, MD, 31 March - 2 April 2009
Biomass-NDVI-LAI patterns and relationships on the Yamal Peninsula, Russia
Epstein, HE, Walker DA, Kaarlejärvi E, Kuss P, Moskalenko NG, Orekhov PT, Gubarkov AA, Khomutov AV, Leibman MO, Matyshak GV
Land Cover, Land Use Change Spring Science Team Meeting, Bethesda, MD, 31 March - 2 April 2009
Greening of Arctic tundra is linked to warming summer land temperatures and sea-ice declines
Bhatt US, Walker DA, Raynolds MK, Comiso JC, Epstein HE, Jia GJ, Gens R
Land Cover, Land Use Change Spring Science Team M, Bethesda, MD, 31 March - 2 April 2009
Vegetation greenness on the Yamal Peninsula, Russia: Disturbance-climate-change interactions
Walker DA, Leibman MO, Epstein HE, Forbes BC, Bhatt US, Raynolds MK, Comiso JC, Gubarkov AA, Khomutov AV, Jia GJ, Kaarlejarvi E, Kaplan JO, Kumpula T, Kuss P, Matyshak G, Orekhov P, Moskalenko NG, Romanovsky V, Ukralentseva NK, Yu Q
Land Cover, Land Use Change Spring Science Team Meeting, Bethesda, MD, 31 March - 2 April 2009
Modelling the distribution of circumpolar arctic vegetation
Raynolds MK, Walker DA, Verbyla D, Huettman F
Land Cover, Land Use Change Spring Science Team Meeting, Bethesda, MD, 31 March - 2 April 2009
Evaluating Environmental Controls on Arctic Tundra Vegetation Dynamics on Yamal Peninsula, Russia
Yu Q, Epstein HE, Walker DA
EnviroDay, University of Virginia, VA, January 12th, 2009

Landscape Change in the Russian Arctic: Ecological Implications of the Petroleum Industry for Nenets Reindeer Herding on the Yamal Peninsula
Kumpula T, Forbes BC, & Stammler F
2008 Annual Meeting and Arctic Forum, Washington, D.C., 13–15 May 2008
Cumulative impacts analysis on the Yamal Peninsula, Russia: A blueprint for a comparative study in Northern Alaska?
Walker DA, Forbes BC, Stammler F, Kumpula T, Gubarkov A, Karlejäarvi E, Bhatt U, Raynolds M, Romanovsky V, Kuss P, Leibman M, Moskalenko N, Khomutov A, Epstein H, Yu Q, Jia J, Comiso J, Kaplan J
Here we summarize some of the recorded effects in the Yamal region of industrial development, the role of terrain sensitivity, reindeer herding, and climate change. Our aim is the co-production of knowledge relevant to assessing the overall cumulative effects – both positive and negative – from past resource exploration and from climate change. We point the way to a comparative study of cumulative effects in North America that would draw on the different lessons learned in both regions, with a goal of collaborating intensively with the local people to develop tools to better predict the cumulative effects of resource development and climate change in these and other regions of the Arctic.
2008 Annual Meeting and Arctic Forum, Washington, D.C., 13-15 May 2008
Abstract
Application of Space-based Technologies and Models to Address Land-cover/Land-use Change Problems on the Yamal Peninsula, Russia: Circumpolar and regional analysis of the relationship between sea-ice variability, summer land-surface temperatures, Arctic tundra greenness and large-scale climate drivers
Bhatt U, Walker DA, Raynolds MK, Comiso J
Recent dramatic reductions in summer sea ice may also impact the ecosystem at high latitudes. It is hypothesized that an earlier ice melt can force atmospheric and land-surface temperatures changes, leading to increased summer warmth and enhanced greenness of vegetation. Our study examines the time-series relationships between sea-ice concentrations, summer land-surface temperatures, vegetation greenness, and large-scale climate drivers within a 50-km buffer of the Arctic coastline for the total Arctic domain and regionally using the Arctic Ocean divisions of the Russian Arctic Atlas. The analysis employs 25-km resolution SSMI passive microwave 18 Jun-22 Jul sea ice concentration and AVHRR Surface Temperature data from 1982 to 2007. The 1982-2006 NASA GIMMS data at a 25-km resolution are used to represent summer NDVI.
NASA Carbon Cycle and Ecosystems Joint Science Workshop, Adelphi, MD, April 28 – May 2, 2008
European Geosciences Union General Assembly 2008, Vienna, Austria, 13 - 18 April 2008
Ecosystem Properties Along a Latitudinal Gradient of the Yamal Peninsula, Russia
Epstein HE, Walker DA, Kuss P, Kaarlejavi E, Matyshek G
An understanding of land-atmosphere and biogeochemical cycling in any system is predicated by knowledge of the spatial distribution of vegetation and soil properties, and the capacity for elements to move among the various system components, including plants, soils, and atmosphere. In many regions of the Siberian arctic tundra, this baseline information on vegetation and soils in a spatial context does not exist in any systematic fshion. As part of a U.S. NASA/NEESPI Land Cover Land Use change project, we analyzed in detail the vegetation and soil properties of three tundra locations along a latitudinal gradient in forest-tundra and arctic tundra in the Yamal Region of Siberia east of the Ural Mountains.
NASA Carbon Cycle and Ecosystems Joint Science Workshop, Adelphi, MD, April 28 – May 2, 2008
European Geosciences Union General Assembly 2009, Vienna, Austria, 14 - 18 April 2008
Application of Space-based Technologies and Models to Address Land-cover/Land-use Change Problems on the Yamal Peninsula, Russia: 2007 field studies along the bioclimate gradient
Walker DA, Epstein HE, Kaarlejärvi E, Kuss JP, Leibman MO, Matyshak GV, Moskalenko NG, Romanovsky VE
The Yamal Peninsula in northern Russia has undergone extensive changes during the past 20 years due to gas and oil development, grazing and trampling by reindeer herds, and changes in climate. We are using a combination of ground-based studies, remote-sensing studies, and studies of land-use activities to help develop vegetation-change models. In 2007-2008 we are establishing a latitudinal transect of six locations in the Yamal Peninsula region. Here we present a summary of ground-based measurements of vegetation, soil, permafrost, active-layer, and spectral reflectance at three sites visited in Aug 2007.
NASA Carbon Cycle and Ecosystems Joint Science Workshop, Adelphi, MD, April 28 – May 2, 2008
European Geosciences Union General Assembly 2008, Vienna, Austria, 13 - 18 April 2008
Evaluating Arctic Tundra System Responses to Grazing Disturbances
Yu Q, Epstein HE
Arctic terrestrial ecosystems are assumed to be one of the most sensitive systems, enduring low temperatures, short growing seasons and freeze-thaw dynamics. The comparatively slow rates of productivity and decomposition may make it particularly difficult for these systems to recover from disturbances. One major disturbance in arctic terrestrial systems is grazing by caribou and reindeer, and different grazing intensities and climate regimes may result in different productivities and plant species compositions.
NASA Carbon Cycle and Ecosystems Joint Science Workshop, Adelphi, MD, April 28 – May 2, 20
European Geosciences Union General Assembly 2008, Vienna, Austria, 14 - 18 April 2008
Cumulative Effects of Industrial Development, Reindeer Herding, and Climate Change on the Yamal Peninsula, Russia
Forbes B
European Geosciences Union General Assembly 2008, Vienna, Austria, 13 – 18 April 2008