Socioeconomics and temperature anomalies: drivers of introduced and native plant species composition and richness in the Canary Islands (1940-2010)

Abstract

Background: Islands are particularly sensitive to biological invasions. The arrival of humans with their cohort of accompanying species has been cited as one of the primary causes for ecosystem change. Question: The introduction of these non-native species has been largely responsible for the tragic disappearance of native island biota and the dismantling of island ecosystems worldwide. Methods: Ordination analyses to determined changes in native and exotic species composition along the period analysed. Results: Mean temperature on the island of Tenerife has increased by around 0.6 °C in the last 70 years,°C in the last 70 years, C in the last 70 years, while minimum temperature has risen by approx. 1.5 °C. Despite overall warming being milder than in°C.Despite overall warming being milder than in C. Despite overall warming being milder than in the northern hemisphere, owing to the more sensitive biota these changes may have a strong influence on biodiversity. In addition, socioeconomic indicators have also changed significantly over the last 70 years with consequences for nature conservation. In this study, we analyse which parameters are best placed to explain the increase of introduced species, not just in terms of species richness, but also in species composition. We restrict the study to thermophile invasive and introduced species, as they respond more rapidly to climate change. Conclusions: We found that socioeconomic aspects of development are important elements that relate closely to the increase in richness and changes in species composition for native as well for introduced species. In the case of invasive species richness, the average minimum temperature is the most closely related variable. However, mean temperature anomalies did not reveal any relationship with these changes. Key words: Canary Islands, CCA, DCA, correlation, global warming, introduced species Aspectos socioeconómicos y anomalías de temperatura: responsables del incremento del número de especies introducidas en las Islas Canarias (1940-2010) ResumenAntecedentes: Las islas son particularmente sensibles a las invasiones. La llegada de humanos con sus especies acompañantes son una de las primeras causas de cambios ecosistémicos. Pregunta: ¿Se relacionan las especies introducidas con la desaparición de especies a lo largo de los ecosistemas insulares del planeta? Métodos: Análisis de ordenación para determinar cambios de riqueza de especies nativas e introducidas a lo largo del periodo. Resultados: La temperatura media de la isla de Tenerife se ha incrementado en 0.6 °C en los últimos 70 años, mientras que la media de las temperaturas mínimas en aproximadamente 1.5 °C. A pesar de que el calentamiento es inferior al sufrido en el hemisferio norte, la mayor sensibilidad de la especies a estos cambios puede provocar negativos efectos en la diversidad. Por otro lado, los indicadores socieconómicos también han cambiado en los últimos 70 años con importantes cambios para el medio natural. En este trabajo analizamos que parámetros se re...

Wildfire Impact and the “Fire Paradox” in a Natural and Endemic Pine Forest Stand and Shrubland

“…The lack of change in this important process affecting the forest patterns resulted in no significant changes in the archipelago. However, there was no change in forest structure, leaving the "fire paradox" as one of the explanations of this pattern, although it is true that an increase of 0.25 • C in temperature [13] since the decade of the 1990s with respect to the new century may have had an influence on this pattern. It is also necessary to highlight that the number of droughts did not increase with respect to other periods before 1980 (www.aemet.es).…”

“…However, these longer periods of fire suppression resulted in recurrently more catastrophic (more difficult to control, with more damage to properties or even harm to humans) and larger individual surface forest fires. The increase in population, gross domestic product, and tourist visitors [13] in the last seven decades can be considered elements that also contributed to these forest patterns (through building of infrastructures and landscape change producing fragmentation, increase in number of fires, long period of suppression, etc.). Moreover, although climate change can be considered one aspect that reinforces this pattern of forest fires, average temperatures on the island of Tenerife (as an indicator of temperature changes for the rest of the archipelago) increased by around 0.6 degrees in the last 70 years [14], in addition to a lack of extreme weather events, such as droughts or big floods.…”

Effects of climate change on the distribution of plant species and plant functional strategies on the Canary Islands

“…Although our models provide robust predictions for the change in potentially climatically suitable area of species native to the Canary Islands, we must address the fact that our models did not include biotic factors, such as species interactions or dispersal. In particular, interspecific competition with succulent invasive species, such as Opuntia and Agave , may be favoured and accelerated by climate change (Arévalo et al, 2017). In addition to habitat destruction, grazing by introduced herbivores poses a massive threat to many native species on the Canary Islands.…”

Monitoring an endangered and rare plant: population growth and viability of Lotus kunkelii (Esteve) Bramwell and Davis (Gran Canaria – Canary Islands)

“…In fact, even the moderate scenarios of the IPCC predict a severe decrease in precipitation and a rise of 3-4 °C in average temperatures in the Mediterranean region (de Castro et al, 2004), with a similar scenario for Canary Islands based on the newest and most precise IPCC estimations (IPCC 2013). So far, changes detected over the past 70 years have revealed an increase of almost 2 °C in minimum average temperatures (Martín et al, 2012;Arévalo et al, 2017). These concerns about possible climate change should also be considered in future conservation plans.…”