Impact of an invasive alien plant on litter decomposition along a latitudinal gradient

Ecosphere

Bente J. Graae¹  Stuart W. Smith¹  Kenny Helsen¹  James D. M. Speed²  Adam Kimberley³  Jan Plue³  Sara A. O. Cousins³  Jonathan Lenoir⁴  Kris Verheyen⁵  Shiyu Ma⁵  Pieter De Frenne⁵  Jörg Brunet⁶  Annette Kolb⁷  Jana Michaelis⁷ 

[1] Department of Biology Norwegian University of Science and Technology Høgskoleringen 5 NO‐7491 Trondheim Norway;Department of Natural History NTNU University Museum Norwegian University of Science and Technology NO‐7491 Trondheim Norway;Department of Physical Geography and Quaternary Geology Stockholm University SE‐106 91 Stockholm Sweden;Edysan (FRE 3498 CNRS) Centre National de la Recherche Scientifique/Université de Picardie Jules Verne 1 rue des Louvels FR‐80037 Amiens Cedex France;Forest & Nature Lab Ghent University Geraardsbergsesteenweg 267 BE‐9090 Gontrode‐Melle Belgium;Southern Swedish Forest Research Centre Swedish University of Agricultural Sciences Box 49 SE‐230 53 Alnarp Sweden;Vegetation Ecology and Conservation Biology Institute of Ecology Faculty of Biology/Chemistry (FB 02) University of Bremen Leobener Strasse 5 DE‐28359 Bremen Germany;

关键词: ecosystem function;    functional traits;    Impatiens glandulifera;    invasive alien species;    latitudinal gradient;    leaf dry matter content;   

DOI  :  10.1002/ecs2.2097

来源: DOAJ

【 摘 要 】

Abstract Invasive alien plant effects on ecosystem functions are often difficult to predict across environmental gradients due to the context‐dependent interactions between the invader and the recipient communities. Adopting a functional trait‐based framework could provide more mechanistic predictions for invasive species' impacts. In this study, we contrast litter decomposition rates among communities with and without the invasive plant Impatiens glandulifera in five regions along a 1600 km long latitudinal gradient in Europe. Across this gradient, four functional traits, namely leaf dry matter content (LDMC), specific leaf area (SLA), stem‐specific density (SSD), and plant height, are correlated to rates of litter decomposition of standardized rooibos (labile), green tea (recalcitrant), and I. glandulifera litter. Our results show that both invaded and non‐invaded plant communities had a higher expression of acquisitive traits (low LDMC and SSD, high SLA) with increasing temperature along the latitudinal gradient, partly explaining the variation in decomposition rates along the gradient. At the same time, invasion shifted community trait composition toward more acquisitive traits across the latitudinal gradient. These trait changes partly explained the increased litter decomposition rates of the labile litter fraction of rooibos and I. glandulifera litter in invaded communities, a shift that was most evident in the warmer study regions. Plant available nitrogen was lower in invaded communities, likely due to high nutrient uptake by I. glandulifera. Meanwhile, the coldest study region was characterized by a reversed effect of invasion on decomposition rates. Here, community traits related to low litter quality and potential allelopathic effects of the invader resulted in reduced litter decomposition rates, suggesting a threshold temperature at which invader effects on litter decomposition turn positive. This study therefore illustrates how functional trait changes toward acquisitive traits can help explain invader‐induced changes in ecosystem functions such as increased litter decomposition.

【 授权许可】

Unknown