Causes and consequences of forest reorganization: Towards understanding forest change

Project Information

FORWARD

Grant agreement ID: 101001905

DOI

10.3030/101001905

EC signature date 27 February 2021

Start date 1 October 2021

End date 30 September 2026

Funded under

• EXCELLENT SCIENCE - European Research Council (ERC)

Total cost

€ 1 965 293,00

EU contribution

€ 1 965 293,00

Coordinated by

TECHNISCHE UNIVERSITAET MUENCHEN
Germany

Periodic Reporting for period 2 - FORWARD (Causes and consequences of forest reorganization: Towards understanding forest change)

Reporting period: 2023-04-01 to 2024-09-30

Summary of the context and overall objectives of the project

Forest ecosystems around the globe are undergoing rapid reorganization. The unabated continuation of climate change, the accelerating rate of alien species introductions, and the precipitous loss of biodiversity are altering the structure and composition of forest ecosystems. As a consequence, the emergence of novel ecosystems is virtually certain. However, the trajectories to novelty and the consequences thereof remain widely unknown. This limits the ability of forest policy and management to counteract undesired developments and safeguard the supply of ecosystem services to society. The FORWARD project investigates the causes and consequences of reorganization in forest ecosystems, jointly studying the effects of global change on tree mortality and regeneration. We use a concerted combination of complementary methodological approaches operating at different spatial scales to understand why reorganization takes place, when and where it is likely to happen, and what impacts reorganization will have on biodiversity and ecosystem services. Extensive experiments are conducted both in the field and in walk-in climate chambers to answer whether compounding climatic extremes could result in bottlenecks of forest regeneration. A next-generation forest landscape model is developed and used to investigate how climate change and alien species alter long-term forest dynamics. Based on these insights the FORWARD project generates operational early warning indicators of reorganization, and conducts in-situ tests of their generality and applicability. In depth analyses of biodiversity and ecosystem service effects will be conducted for national parks with different forest disturbance regimes on three continents. Also, a global synthesis effort will analyze global hotspots of forest reorganization, while regionally robust strategies for addressing reorganization in management will be developed. The FORWARD project will bring about a new level of understanding of forest change, and will provide the data, tools and strategies to tackle one of the most pressing challenges of current forestry.

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

In the first 36 months of the project, the FORWARD team has made the following major achievements:
– the development and publication of a conceptual framework of post-disturbance forest reorganization, setting the agenda and frame for the analyses conducted within the project (WP0);
– the setup of a suite of connected experiments to test interactive abiotic and biotic drivers of forest reorganization in situ (Berchtesgaden National Park) as well as in walk-in climate chambers (WP1). The experimental work has concluded in the fall of 2024, with a focus on data analysis and publication in the next project period;
– the development and publication of the next-generation forest landscape model iLand 2.0 including the publication of source code and parameters for 150 tree species (WP2).
– concerted simulation and analyses of the three FORWARD study sites across three continents (Grand Teton National Park, Berchtesgaden National Park, Shiretoko National Park), towards a better understanding of how climate change results in the reorganization of forest landscapes with widely different disturbance regimes (WP3). This work is ongoing, with the first paper already published, and will be continued in the next period of the project;
– the analysis of reorganization impacts on ecosystem services and biodiversity and the development of management response strategies (WP4). Here we have focused particularly on disturbance impacts on ecosystem services (including an economic valuation), as well as on management response strategies related to uneven-aged forest management and the reforestation of disturbed areas with tree species robust to future climate change. In the next period of the project in situ assessments of biodiversity and ecosystem services will be conducted for the three main study systems of the project; and
– the assessment of global hotspots of climate risks in forest ecosystems (WP5), and the improved simulation of major reorganization processes such as disturbance in forest models. In the next project period a further analysis on global forest structure is planned.
Overall, the FORWARD team has published 39 papers in peer-reviewed journals in the first 36 months of the project, including works in Science, PNAS, Nature Ecology and Evolution as well as Global Change Biology.

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

The project has made considerable progress beyond the state of the art, including
- the presentation of an operational framework to assess and quantify forest reorganization (https://doi.org/10.1073/pnas.2202190119);
- important insights on novel forest disturbances, e.g. the finding that forest fires could become more important also in parts of Europe not currently affected by fires, such as Central Europe (https://doi.org/10.1111/gcb.16547);
- the development of remote sensing-based early warning indicators for regime shifts and forest loss after disturbance (https://doi.org/10.1016/j.rse.2024.114194)
- a better understanding of potential future forest change in Central Europe, including the insight that climate-mediated changes in the forest disturbance regimes might be more important for future forest trajectories than the direct effects of warming (https://doi.org/10.1111/gcb.16133);
- the insight that past disturbances can increase the resilience of forest landscapes to future change, but that regime shifts are also likely if future climate-induced disturbance activity exceeds critical thresholds (https://doi.org/10.1111/gcb.17468)
- a spatially explicit risk assessment for forest ecosystem services in Europe to wildfire, windthrow and bark beetles (https://doi.org/10.1111/gcb.17242)
- the identification of tree species that are suitable for the reforestation of currently disturbed areas in Europe in the context of current and expected future climate (https://doi.org/10.1038/s41559-024-02406-8)
- an assessment of how processes important for simulating forest reorganization, such as tree mortality and regeneration, are represented in models (https://doi.org/10.1111/1365-2745.13989); and
- the identification of global climate risks to forests (https://doi.org/10.1126/science.abp9723).

Until the end of the project we expect further progress from
- experiments on abiotic and biotic drivers of forest reorganization;
- the application of the next-generation forest landscape model iLand 2.0 towards questions of forest reorganization;
- an analysis of processes driving forest reorganization across landscapes with different disturbance history and disturbance response mechanisms;
- the assessment of carbon and biodiversity effects of reorganization across the three main FORWARD study systems;
- the evaluation of specific forest management strategies in the context of changing forest disturbance regimes; and
- analyses ongoing forest reorganization after the recent major disturbance pulse in Central Europe

A concept of post-disturbance forest reorganization (Seidl & Turner 2022, PNAS 119, e2202190119)