Pioneer annual vegetation of gravel-bed rivers: first insights on environmental drivers from three Apennine streams

Journal of Limnology

Rossano Bolpagni¹  Alice Dalla Vecchia¹ 

[1]Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma

关键词: herbaceous riverine plants;    hydrogeomorphic disturbance;    sediment granulometry;    diversity;    invasive species;    Emilia-Romagna;   

DOI  :  10.4081/jlimnol.2021.2052

来源: DOAJ

【 摘 要 】

A huge knowledge gap exists on riverine pioneer herbaceous vegetation. Despite its relevance in regulating the C metabolism at the catchment scale, and the triggering role in shrubs and trees establishment along riverbanks, little data is available on its environmental determinants. Indeed, most existing knowledge in this field refers to woody species or aquatic macrophytes neglecting the ecosystem relevance of ephemeral herbaceous vegetation. Focusing on three gravel bed rivers located in northern Italy (Baganza, Nure and Parma streams), the present study is aimed to evaluate the riverine ephemeral plant richness, considering both native and alien taxa, and the role of hydrogeomorphological disturbance and sediment quality in the observed richness patterns. At higher disturbance rates (e.g., larger river sizes), our data indicates a progressive decrease in overall plant richness, but also an increase in the coverage-abundance rates mainly due to alien species. This evidence confirms that variations in hydrology imply changes in pioneer plant species richness at in-stream periodically exposed sediments. More attention must be given to the vulnerability of pioneer vegetation to climate change and direct human impacts to fully understand the functioning of lotic ecosystems, especially the non-perennial ones.

【 授权许可】

Unknown