Primary succession encompasses the earliest and most fundamental stages of community assembly. The relative contributions of plant dispersal and ecosystem development, the main drivers that control the rate of primary succession, remain largely unknown, in spite of their central roles in community organization in general. Understanding the contribution of dispersal is especially critical because it casts light on our ability to manage succession resulting from climate change or anthropogenic disturbance. Here, we review the literature in order to understand when and where dispersal limits primary succession. Studies from many systems (tropical, temperate, boreal, arctic, alpine, floodplain forest, desert, mines, volcanic eruption and glacier forelands) show that dispersal limitation occurs consistently in the early stages of primary succession, suggesting that this is a general pattern. On the other hand, we found strong biases in study sites towards the Northern Hemisphere, temperate regions, volcanic eruptions and glacier forelands, which suggests that there are risks in drawing general conclusions about the importance of dispersal for primary succession for other biomes. Little is known about the contribution of dispersal to the later stages of primary succession. We present a recently developed method, multiscale chronosequence comparison that compares rates of succession in similar systems at relatively small and large spatial scales. Rapid succession at small scales compared to large scales suggests that seed dispersal influences succession over time periods of centuries and also limits the development of ecosystem functions such as vegetation cover and soil carbon accumulation. Synthesis: Dispersal limitation likely matters not only in the early stages but also in the late stages of primary succession by controlling the rate at which new species arrive. Both the accumulation of comparable case studies and novel approaches, such as multiscale chronosequence comparisons and factorial experiments, in contrasting biomes, are necessary to clarify the generality or context dependency of the role of dispersal in future primary successions undergoing changing climate.

We summarize current knowledge about the ecosystem functions of fire‐produced charcoal in boreal forests with a special focus on its effects on soil carbon, nitrogen and phosphorous dynamics as well as on plant succession. Charcoal is a carbon‐enriched material with a highly aromatic and porous structure. Charcoal is highly resistant to microbial decomposition and thus remains in soil for thousands of years, providing recalcitrant carbon to boreal forest soils. The abundant pores in and on charcoal surfaces have powerful adsorption abilities that can influence biogeochemical cycles and plant succession after fire. Our review details the influence of charcoal on plant and soil systems and explains the complex direct and indirect pathways of these influences that occur during succession after fires in boreal ecosystems. Among these pathways, the most important pathway through which charcoal influences plant and soil systems relates to the element composition and nutrient availability in soils and to the abundance of phenolics released from Ericaceae plants in the understory of boreal forests. We found a strong bias in the studied processes towards nutrient mineralization rather than immobilization, which suggests that it is risky to draw general conclusions about the influence of charcoal on soil nutrient dynamics. Last, the latest studies shed light on the enhancement of litter and humus decomposition by charcoal, given the possibility that charcoal accelerates CO ₂ release in a postfire forest. This review suggests comparative studies that are necessary to test the context‐dependency of charcoal functions across a variety of boreal forest ecosystems.