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Northern Eurasia Future Initiative (NEFI): facing the challenges and pathways of global change in the 21st century
During the past several decades, the Earth system has changed significantly, especially across Northern Eurasia. Changes in the socio-economic conditions of the larger countries in the region have also resulted in a variety of regional environmental changes that can
have global consequences. The Northern Eurasia Future Initiative (NEFI) has been designed as an essential continuation of the Northern Eurasia Earth Science
Partnership Initiative (NEESPI), which was launched in 2004. NEESPI sought to elucidate all aspects of ongoing environmental change, to inform societies and, thus, to
better prepare societies for future developments. A key principle of NEFI is that these developments must now be secured through science-based strategies co-designed
with regional decision makers to lead their societies to prosperity in the face of environmental and institutional challenges. NEESPI scientific research, data, and
models have created a solid knowledge base to support the NEFI program. This paper presents the NEFI research vision consensus based on that knowledge. It provides the reader with samples of recent accomplishments in regional studies and formulates new NEFI science questions. To address these questions, nine research foci are identified and their selections are briefly justified. These foci include: warming of the Arctic; changing frequency, pattern, and intensity of extreme and inclement environmental conditions; retreat of the cryosphere; changes in terrestrial water cycles; changes in the biosphere; pressures on land-use; changes in infrastructure; societal actions in response to environmental change; and quantification of Northern Eurasia's role in the global Earth system. Powerful feedbacks between the Earth and human systems in Northern Eurasia (e.g., mega-fires, droughts, depletion of the cryosphere essential for water supply, retreat of sea ice) result from past and current human activities (e.g., large scale water withdrawals, land use and governance change) and
potentially restrict or provide new opportunities for future human activities. Therefore, we propose that Integrated Assessment Models are needed as the final stage of global
change assessment. The overarching goal of this NEFI modeling effort will enable evaluation of economic decisions in response to changing environmental conditions and justification of mitigation and adaptation efforts
Vegetation characteristics and eco-hydrological processes in a pristine mire in the Ob River valley (Western Siberia)
Relations between vegetation characteristics
and eco-hydrological processes were
assessed in a pristine mire in the valley of the
Ob River (Western Siberia). Along a transect
from the terrace scarp to the river, field data were
collected on vegetation composition, peat stratigraphy,
peat chemistry, hydrology and hydrochemistry.
Based on floristic composition, eight
vegetation communities were distinguished.
Hydraulic head measurements were used to
obtain an indication of groundwater flow directions.
The water balance of the mire was calculated
with a two-dimensional steady-state
numerical groundwater model. Water types were
defined based on cluster analysis of hydrochemical
data. The results revealed that the dominant
hydrological factor in the Ob mire is the discharge
of groundwater, which supplies about threefold
more water than net precipitation. Although the
discharge flux decreases with increasing distance
from the terrace scarp, high water levels and a
‘‘groundwater-like’’ mire water composition were
observed in the major part of the study site.
Precipitation and river water play only a minor
role. Despite dilution of discharging groundwater
with rainwater, spatial differences in pH and
solute concentrations of the surficial mire water
are small and not reflected in the vegetation
composition. Although small amounts of silt and
clay were found in the peat in the proximity of the
river, indicating the occurrence of river floods in
former times, no river-flood zone could be recognized
based on hydrochemical characteristics or
vegetation composition. A comparison of the Ob
mire with well-studied and near-natural mires in
the Biebrza River valley (Poland) revealed
substantial differences in both vegetation characteristics
and the intensity and spatial pattern of eco-hydrological processes. Differences in the origin and ratios of water fluxes as well as a
dissimilar land use history would seem to be key
factors explaining the differences observed