Acta Scientiarum Polonorum
Silvarum Colendarum Ratio et Industria Lignaria

Ongoing climate change, manifested by increasing air temperature and altered precipitation regimes, significantly affects forest ecosystem functioning and tree health. This study aimed to assess spatial differences in the scale and dynamics of tree mortality of Scots pine (Pinus sylvestris L.) and pedunculate oak (Quercus robur L.) in relation to climatic conditions and local hydrological constraints, with particular emphasis on the influence of the Tarchalice–Domaszków flood polder system. The research was conducted in three forest units (Tarchalice, Dębno and Prawików) within the Wołów Forest District (south-western Poland) over the period 2014–2023.

Tree mortality was assessed indirectly using the volume of salvage logging, expressed per unit area (m³·ha⁻¹·year⁻¹), as an integrated indicator of tree decline. Analyses were performed separately for pine and oak stands. Climatic variables included annual precipitation totals and mean annual air temperature, derived from the Wrocław–Strachowice meteorological station. Relationships between salvage logging intensity and climatic variables were examined using Pearson and Spearman correlation analyses.

The results revealed pronounced spatial differences in mortality patterns among the analysed forest units. Scots pine exhibited a relatively rapid and continuous response to environmental stress, reflected by interannual variability in salvage logging intensity, particularly in the Dębno forest unit. In contrast, pedunculate oak showed delayed but pronounced episodic mortality, most notably in the Tarchalice forest unit, which is strongly affected by a highly variable hydrological regime associated with the flood polder. No statistically significant linear correlations were found between salvage logging intensity and individual climatic variables, indicating that tree responses to climatic stress are delayed and cumulative rather than immediate. The findings highlight the dominant role of local hydrological and site conditions over regional climatic indicators in shaping tree mortality patterns and underline the necessity of adaptive forest management strategies in flood-affected forest landscapes.