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Significance Understanding the impacts of urbanization and the associated urban land expansion on species is vital for informed urban planning that minimizes biodiversity loss. Predicting habitat that will be lost to urban land expansion for over 30,000 species under three different future scenarios, we find that up to 855 species are directly threatened due to unmitigated urbanization. Our projections pinpoint rapidly urbanizing regions of sub-Saharan Africa, South America, Mesoamerica, and Southeast Asia where, without careful planning, urbanization is expected to cause particularly large biodiversity loss. Our findings highlight the urgent need for an increased focus on urban land in global conservation strategies and identify high-priority areas for this engagement.

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Spatial heterogeneity in the intensity of past disturbances has directly influenced the structure and composition of present-day forests around the world. In south-eastern Australia infrequent, high-intensity wildfires are a major part of the historical disturbance regime. While these fires are often assumed to produce even-aged stands, spatial heterogeneity in fire intensity due to highly variable topography may lead to more complex forest age structures. Our study describes the influence of disturbance on the age structure and dynamics of a mosaic of tall, open eucalypt forest, cool temperate rainforest and mixed species forest surrounding Bellel Creek in the Central Highlands of Victoria using dendrochronological techniques. We were particularly interested in the impacts of the 1939 Black Friday fire and its effects on forest age structure and subsequent stand development patterns. Within our study site tall open forest displayed two distinct age cohorts: (i) trees that established immediately after the 1939 fire and accounted for the majority of individuals in the forest, and (ii) scattered groups of older trees estimated to be approximately 200-250 years old. Cool temperate rainforest and mixed forest were also dominated by the post-1939 fire age cohort. However, a greater proportion of trees in these forest types survived the 1939 fire relative to the tall open forest.The impact of the 1939 fire on the growth of surviving trees was highly variable but generally short-lived. In most cases growth decreased after the 1939 fire, but generally returned to prefire levels within 1-3 years. Non-fire disturbances were limited to small-scale branch-and tree-fall events, although the extreme snowstorm of 1977 appears to have caused extensive damage to rainforest communities. Our study demonstrates the opportunities for dendroecological studies to reconstruct historical dynamics and disturbance patterns in Australian forests and provides important insights into variation in landscape-scale fire impacts and their effect on subsequent forest development patterns.

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