Age and area predict patterns of species richness in pumice rafts contingent on oceanic climatic zone encountered

Abstract

The theory of island biogeography predicts that area and age explain species richness patterns (or alpha diversity) in insular habitats. Using a unique natural phenomenon, pumice rafting, we measured the influence of area, age, and oceanic climate on patterns of species richness. Pumice rafts are formed simultaneously when submarine volcanoes erupt, the pumice clasts breakup irregularly, forming irregularly shaped pumice stones which while floating through the ocean are colonized by marine biota. We analyze two eruption events and more than 5,000 pumice clasts collected from 29 sites and three climatic zones. Overall, the older and larger pumice clasts held more species. Pumice clasts arriving in tropical and subtropical climates showed this same trend, where in temperate locations species richness (alpha diversity) increased with area but decreased with age. Beta diversity analysis of the communities forming on pumice clasts that arrived in different climatic zones showed that tropical and subtropical clasts transported similar communities, while species composition on temperate clasts differed significantly from both tropical and subtropical arrivals. Using these thousands of insular habitats, we find strong evidence that area and age but also climatic conditions predict the fundamental dynamics of species richness colonizing pumice clasts.

The ecology of Lepas-based biofouling communities on moored and drifting objects, with applications for marine forensic science

“…Debris surface area was also positively correlated with abundance of Lepas, a relationship observed for biofoulers in other studies (Dellinger et al 1997;Velasquez et al 2018). Similarly, Goldstein et al (2014) found a positive correlation between object size and biofouler diversity.…”

“…Surface area of shore-cast debris was strongly positively correlated with maximum length of L. anserifera. This is potentially related to the greater stability of larger, heavier objects (Velasquez et al 2018), with floating behaviour of drifting objects strongly influencing biofouling communities (Bravo et al 2011). Studies using mooring biofouling communities as proxies for those on free-drifting debris may therefore be more accurate when applied to larger, more stable debris.…”

Massive Drift of Pumice Stones Might Trigger Coastal Ecological Transitions

“…Biofauling of sessile organisms on pumice stones rafting near Okinawa Island Some pumices observed on the Okinawa beach had already become habitats for sessile organisms (Fig. 4), as reported in previous studies [21][22][23][24][25]. Goose barnacles (Lepas sp.)…”

“…If the symbiotic relationship breaks down, the coral tissue will turn white (bleaching), and in the worst case, the coral will die [44,45]. Previous studies discussed that pumice rafts contribute to coral dispersal [21][22][23][24], and rafts may support escape of juvenile coral from unfavorable conditions such as local stress [25]. But the negative aspects of pumice drift are still unclear.…”

Defining Pre-eruptive Conditions of the Havre 2012 Submarine Rhyolite Eruption Using Crystal Archives

“…To date the majority of studies on the Havre 2012 submarine eruption have focused on the limited volume (< 0.1 km 3 or 7% of the total eruptive material) seafloor eruptive products (e.g., Carey et al, 2014Carey et al, , 2018Manga et al, 2018a,b;Ikegami et al, 2018;Mitchell et al, 2018Mitchell et al, , 2019Murch et al, 2019). Studies on the volumetrically dominant pumice raft (∼1.4 km 3 or 93% of total eruptive material) has been at a reconnaissance level, examined limited material (e.g., Rotella et al, 2015;Manga et al, 2018b) and focused on raft dispersion (e.g., Jutzeler et al, 2014;Carey et al, 2014;Velasquez et al, 2018). One outcome of the seafloor-focused studies has been the interpretation that the giant seafloor pumice and pumice raft were erupted contemporaneously (Manga et al, 2018a,b) given near identical whole-pumice compositions, similar mineralogy (i.e., plagioclase, orthopyroxene, clinopyroxene and Fe-Ti oxides) and textural features (e.g., banded pumice, tubed pumice and bread crusting).…”