How Do Wood Anatomical Traits in Salix Vary in Response to Flooding? A
Case Study from the Yenisei River, Siberia
Abstract
Recent, record-breaking discharge in the Yenisei River, Siberia, is part
of a larger trend of increasing river flow in the Arctic driven by
Arctic amplification. These changes in magnitude and timing of discharge
can lead to increased risk of extreme flood events, with implications
for infrastructure, ecosystems, and climate. To better understand the
changes taking place, it is useful to have records that help place
recent hydrological changes in context. In addition to an existing
network of river gauges, extreme flood events can be captured in the
wood anatomical features of riparian trees, which help identify the most
extreme flood events. Along the Yenisei River, Siberia we collected
willow (Salix spp.) samples from a low terrace that occasionally floods
when water levels are extremely high. Using these samples, we use an
approach known as quantitative wood anatomy to measure variation in
radial cell dimensions, including vessel area, wood fiber size and cell
wall thickness. We then compare these measurements to observed records
of flood stage. We hypothesize that (1) characteristic patterns of wood
fiber size and cell wall thickness in Salix rings are present during
flood years, (2) these patterns can be quantified by measuring wood
fiber size and cell wall thickness, and (3) quantified variations in
cell anatomical properties can be related to flood magnitude and
duration. Understanding how riparian vegetation responds to extreme
flood events can help us better manage riparian ecosystems and
understand changes to the Arctic hydrological regime.