Modelling the impacts of future land use and climate change on ecosystem services in the European Arctic using LPJ-GUESS

Abstract

Climate change and socio-economic developments are projected to intensify land use pressures in northern latitudes, potentially driving agricultural expansion into Arctic and boreal ecosystems. This thesis examines the consequences of future climate and land use change on ecosystem services in the European Arctic, focusing on vegetation dynamics, carbon storage, crop productivity, and biophysical feedbacks such as albedo and soil temperature.
Using the dynamic global vegetation model LPJ-GUESS, simulations were conducted from 1850–2100 under two contrasting Shared Socioeconomic Pathways (SSP1-2.6 and SSP3-7.0), along with fixed CO₂ and land use scenario variants. The study region spans 3°–60°E and 60°–73°N. Key ecosystem functions were assessed through spatial and temporal analyses of model output, including gross primary productivity (GPP), net ecosystem exchange (NEE), vegetation and soil carbon stocks, crop yield, active layer depth, and surface albedo.
Results suggest that while warming and elevated CO₂ can enhance productivity and support northward treeline shifts, they are also accompanied by losses in soil carbon and declining albedo, particularly where forest replaces tundra or pastures expand. Vegetation composition shifted towards more deciduous trees in the southern boreal zone, while in northern tundra regions, warming promoted shrubification, woody shrubs expanding into previously open landscapes. These changes alter seasonal reflectivity and carbon cycling, and may reduce reindeer pasture quality.
Under high-expansion scenarios, carbon losses from vegetation and soils outweighed yield gains in many regions. Simulated warming led to deeper active layers, especially in tundra zones, indicating increased permafrost vulnerability. Although crop suitability improved in some southern areas, overall trade-offs suggest that unregulated expansion could undermine climate mitigation.
This study underscores the importance of integrated land use planning in northern regions, where climate-driven cultivation opportunities must be balanced against long-term ecosystem service sustainability and the needs of traditional land users.

Popular Abstract

As the Arctic warms nearly four times faster than the global average, the landscapes of the European Arctic are undergoing dramatic transformations. Longer growing seasons, thawing permafrost, and shifting vegetation zones are no longer future scenarios, they are already underway. These changes open up the possibility for agriculture to expand into areas that were previously too cold to farm, particularly in parts of northern Norway, Sweden, Finland, and Russia.
But with new opportunities come new risks. Expanding farmland can release carbon stored in forests and soils, reduce the ground’s reflectivity (albedo), and threaten natural ecosystems and traditional land use. In this thesis, I used a computer model that simulates ecosystem’s response to climate and land use changes (called LPJ-GUESS) to simulate what might happen in the European Arctic under two future scenarios: one focused on sustainability, and one on rapid economic growth with high land use pressure.
The model also showed noticeable shifts in vegetation. In southern areas, deciduous forests became more common, while in the north, low shrubs began to invade formerly open tundra, a process called "shrubification." These changes can make the land darker, warming it further, and may reduce the quality of pastures that reindeer depend on.
The results show that while higher levels of carbon dioxide and warmer conditions can increase vegetation productivity, these gains are often offset by losses in soil carbon and climate-warming effects from land use change. Areas suitable for future farming were mapped, and in some cases, crop expansion could be achieved with minimal climate cost, especially where snow-covered forest is replaced by open farmland.
This work highlights the double-edged sword of climate change in the Arctic: it creates new possibilities, but also magnifies trade-offs. As we move toward an uncertain future, decisions about land use will need to balance food production with climate responsibility and ecosystem protection.

• author: Benner, Juliane Lara
• supervisor: Paul Miller
• organization: Dept of Physical Geography and Ecosystem Science
• course: NGEM01 20251
• year: 2025
• type: H2 - Master's Degree (Two Years)
• subject: Earth and Environmental Sciences
• keywords: Physical Geography and Ecosystem science, climate change, land use change, agricultural expansion, ecosystem services, LPJ-GUESS
• publication/series: Student thesis series INES
• report number: 733
• language: English
• id: 9205785
• date added to LUP: 2025-06-25 16:54:21
• date last changed: 2025-06-25 16:54:21