Primary succession | EPFL Graph Search

Primary succession is the beginning step of ecological succession after an extreme disturbance, which usually occurs in an environment devoid of vegetation and other organisms. These environments are typically lacking in soil, as disturbances like lava flow or retreating glaciers scour the environment clear of nutrients. In contrast, secondary succession occurs on substrates that previously supported vegetation before an ecological disturbance. This occurs when smaller disturbances like floods, hurricanes, tornadoes, and fires destroy only the local plant life and leave soil nutrients for immediate establishment by intermediate community species. In primary succession pioneer species like lichen, algae and fungi as well as abiotic factors like wind and water start to "normalise" the habitat or in other words start to develop soil and other important mechanisms for greater diversity to flourish. Primary succession begins on rock formations, such as volcanoes or mountains, or in a place with no organisms or soil. Primary succession leads to conditions nearer optimum for vascular plant growth; pedogenesis or the formation of soil, and the increased amount of shade are the most important processes. These pioneer lichen, algae, and fungi are then dominated and often replaced by plants that are better adapted to less harsh conditions, these plants include vascular plants like grasses and some shrubs that are able to live in thin soils that are often mineral-based. Water and nutrient levels increase with the amount of succession exhibited. The early stages of primary succession are dominated by species with small propagules (seed and spores) which can be dispersed long distances. The early colonizers—often algae, fungi, and lichens—stabilize the substrate. Nitrogen supplies are limited in new soils, and nitrogen-fixing species tend to play an important role early in primary succession. Unlike in primary succession, the species that dominate secondary succession, are usually present from the start of the process, often in the soil seed bank.

Ecosystem engineering by periphyton in Alpine proglacial streams

Tom Ian Battin, Davide Mancini, Marc Aguet, Adrijan Selitaj, Matteo Roncoroni

Stream periphytons are candidate ecosystem engineers in proglacial margins. Here, we quantify the extent to which they are engineers for the case of hillslope-fed tributaries in the terrace zones of proglacial margin alluvial plains. Candidate ecosystem en ...

WILEY2023

Model-based data analysis of the effect of winter mixing on primary production in a lake under reoligotrophication

Alfred Johny Wüest, Hugo Nicolás Ulloa Sánchez, Camille Roland Marie Minaudo, Shubham Krishna

Nutrient loading, in combination with climate change are important drivers of primary productivity in lakes. Understanding and forecasting future changes in primary production (PP) in response to local and global forcing are major challenges for developing ...

2020