Effects of Carpobrotus edulis invasion on main litter and soil characteristics in backdune and rocky coastal habitats with oceanic climate

Abstract

Background and aims: Carpobrotus edulis invades coastal areas throughout the world, decreasing plant diversity and hampering restoration efforts by changing soil properties. Some of its effects on soils are known but there is a knowledge gap about the effects in rocky areas and micronutrients that we aimed to fill for dunes and rocky habitats with temperate-humid climate. Methods: We compared invaded vs non-invaded paired plots in two backdune and two rocky areas by measuring 18 variables in litter and 24 in soils (0-5 and 5-10 cm layers). Results: Invasion effects increased with the accumulated alien necromass, decreased with soil depth and are substrate-dependent: soil pH, Al, Fe and P increased in dunes, while these variables and Mg, Cu and Zn decreased in rocky sites. Carpobrotus necromass is richer in Mg and Ca and poorer in Al, Co, Cu, Fe, Ni and Zn than native necromass. Conclusions: Invader effects on soils are largely mediated by its necromass, which has contrasting characteristics with the autochtonous necromass. Carpobrotus edulis ability to discriminate against Al uptake, while favouring Mg and Ca uptake, and its lower requirement (or higher resorption) of key micronutrients (Co, Cu, Fe, Ni, Zn) than native vegetation could partly explain its invasiveness.

Native plant community recovery after Carpobrotus (ice plant) removal on an island — results of a 10‐year project

“…These two characteristics make Carpobrotus species hard to eradicate when they are well established because they can resprout from leftover fragments and they can germinate from their dense long‐term seed bank. Carpobrotus species affect soil parameters: they increase litter, may change C and N fluxes as well as pH, Al, Fe, Ca, Na, Mg, Cu, Zn and P concentrations (Affre, 2011; Santoro et al, 2011; Novoa et al, 2013; Vieites‐Blanco and González‐Prieto, 2018a; Vieites‐Blanco and González‐Prieto, 2018b). They: (a) directly compete with native plants for space, water and light, reducing their establishment, growth and survival (Campoy et al, 2018), ultimately decreasing native plant species richness and diversity up to the ‘extirpation’ of plant functional groups and life forms (Vilà et al, 2006; Affre, 2011; Fried et al, 2014); (b) negatively impact arthropods and reptiles (Orgeas et al, 2007; Galán, 2008); and (c) change native pollinator networks (Moragues and Traveset, 2005; Affre, 2011).…”

Ecophysiological differentiation between two invasive species ofCarpobrotuscompeting under different nutrient conditions

“…and Carpobrotus acinaciformis (L.) L.Bolus (Aizoaceae) are trailing, mat‐forming succulent perennial herbs (Wisura and Glen, ) that inhabit coastal habitats in temperate regions around the world (Campoy et al., ). Their success in invading new areas has been attributed to several factors: their capacity to alter the invaded soils (Vieites‐Blanco and González‐Prieto, , b); their “grow‐and‐die” strategy, which transforms a hostile environment into a more favorable habitat for their offspring (Fenollosa et al., ) and a greater competitive ability than native species (D'Antonio and Mahall, ).…”

Demographic analysis of an Israeli Carpobrotus population

“…Our results show a Carpobrotus population with a stable growth rate ( Table 1 , Fig 3 ), indicating that this population is neither declining nor expanding if the environmental conditions under which it was examined do not change. There are a few reasons that might explain why Carpobrotus , which is known to be highly invasive in other places [ 8 , 36 – 38 ], might not be expanding at our site in Israel. First, our Havatselet population might be an old population that has reached an ‘equilibrium’ and is now limited by space [ 34 , 61 , 62 ].…”

“…survival, growth) to target with management [29,[31][32][33][34][35]. Most research on Carpobrotus has focused on a determining its effects on other species in their ecological communities and on quantifying individual vital rates and their vulnerability to various management strategies [17,[36][37][38]. To date, no studies have conducted a comprehensive demographic analysis of any species in the Carpobrotus genus.…”