Shachar has been fascinated by nature for as long as he can remember. Birdwatching, trekking, scuba diving, and wildlife have always been part of his life. Accordingly, he enrolled in a bachelor’s program in environmental engineering at the Technion, which he found fascinating, though he mostly enjoyed the physics and mathematics. During the last year of his bachelor’s, he began working as a research engineer in a startup company aiming to enable efficient green hydrogen production – h2pro. After another year and a half as a full-time engineer in the simulation-analysis group at h2pro, he started his master’s in environmental physics at the Sde Boker campus, BGU. The master’s program led to a combined track to a PhD, continuing to use tools from nonlinear dynamics to reveal phenomena in dryland and arctic tundra ecosystems.

Research Project: Multi level ecosystem response to climate variations

Shachar’s current research project focuses on the tundra ecosystem, and specifically understanding the non-linear relationship between the vegetation and the thermal regime. The tundra is a unique ecosystem in which the entire soil column freezes during the (cold and prolonged) winter, and the top layer only (the ‘active layer’) thaws during the summer. It has been the focus of many recent studies, due to the large carbon pool stored in tundra soils, and the high impact of climate warming on these ecosystems.

Field research from the past several decades reveal that the vegetation in the tundra is not only affected by the thermal regime, but also plays a key role in shaping it. One of the principal factors is the ‘winter insulation effect’. In winters, vegetation traps snow by disturbing the winds, and physically holding snow within the stems, branches and leaves. This, in turn, leads to a higher snow pack, that insulates the soil, and the plant, from the harsh winter – that can reach temperatures of 40 C and less. Incorporating vegetation responses to environmental factors, many field data, and dynamical modelling – he tries to decipher the complex mutual dynamics of the thermal regime and the vegetation, cooperating with ‘team shrub’ from Vancouver, Canada.

The strong annual periodicity, many variables involved, and the harsh conditions in the tundra which make field data limited – makes it a challenge. These dynamics that might provoke shrubification – a widely observed phenomenon of shrubs taking over tundra ecosystems – are in high interest, and might explain the underlying mechanism.