2026-04-13T06:56:13Zhttps://recercat.cat/oai/requestoai:recercat.cat:10256/285532026-03-27T00:12:38Zcom_2072_452966com_2072_2054col_2072_452968
RECERCAT
author
Sagarra Navarro, Àlex de
2026-03-27T00:12:38Z
2026-03-27T00:12:38Z
2025-07
https://hdl.handle.net/10256/28553
The Mediterranean is the sea with the most invasive species in the world, mainly due to
the amount of activities carried out there (aquaculture and overcrowding, among others)
and the presence of the Suez Canal. This is one of the main reasons why the biodiversity
of the ecosystems in this sea is being depleted. One of the most recent examples is the
invasion of Rugulopteryx okamurae, an algae from the northwestern Pacific that is
spreading alarmingly across the southern Iberian Peninsula. This study seeks to
determine what role the expected rise in temperatures in the coming years will play in
this invasion, both in terms of the direct impact on the growth of the invasive algae and
the indirect impact through the effect of temperature on native herbivores, specifically
the sea urchin Paracentrotus lividus, as these could act as biocontrol agents on the
algae.
Specifically, two experiments were carried out: in the first, the thermotolerance of R.
okamurae was determined. The results indicate that the optimum growth point is
between 16°C and 24°C; below this (10°C and 14°C) there is no growth of the algae and
above 26°C it is unable to survive. This study also served to establish the temperature
range for the second experiment, in which individuals of P. lividus were subjected to
14°C, 18°C, 22°C, and 26°C, and the consumption of R. okamurae was measured. The
results indicate that P. lividus is capable of consuming the invasive algae and that this
consumption is independent of temperature.
The study offers a new perspective, focusing on how the invasion of R. okamurae could
evolve in the coming years, taking into account not only environmental conditions but
also biotic factors such as herbivory. It has been observed that temperature is a key
factor in its expansion and that the P. lividus could exert biological control over the algae
under certain circumstances. The study contributes to our understanding of the
mechanisms of interaction between native and invasive species and highlights the need
for further research into sustainable strategies to curb the spread of R. okamurae in the
Mediterranean14
Attribution-NonCommercial-NoDerivatives 4.0 International http://creativecommons.org/licenses/by-nc-nd/4.0/ info:eu-repo/semantics/openAccess
Paracentrotus lividus
Rugulopteryx okamurae
Algues brunes -- Efecte de la temperatura -- Mediterrània, Mar
Eriçons de mar -- Mediterrània, Mar
Espècies introduïdes -- Mediterrània, Mar
Brown algae -- Effect of temperature on -- Mediterranean Sea
Sea urchins -- Mediterranean Sea
Introduced organisms -- Mediterranean Sea
Efecte de la temperatura sobre la capacitat de Paracentrotus lividus per al biocontrol de Rugulopteryx okamurae
info:eu-repo/semantics/bachelorThesis