Conferencia: Las diversas caras de la biodiversidad
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Transcript of Conferencia: Las diversas caras de la biodiversidad
Las diversas
caras de la biodiversidadFernando Valladares
Los humanos van camino de extinguir a todos los demás primates• En medio siglo habrán desaparecido el 75% de las especies
de simios, monos y lémures• El 60% ya están amenazados o en peligro
El cambio global arrastra organismos
En un solo día desaparecen 70 especies, (100-1000 mas rápido que la tasa natural)
La sexta gran extinciónSobrexplotación de recursos.
Siglo XIX. Montaña de cráneos de bisonte americano
Dos mensajes1. La biodiversidad está amenazada2. La biodiversidad es algo mas que el número
de especies: es la base del funcionamiento de los ecosistemas y de los servicios que nos brindan
Biodiversity changeFactor of global change
Impact on “ecosystem functioning” and the delivery of “ecosystem services”?
“Does biodiversity matter?”
• “Activities, processes or properties of ecosystems that are influenced by its biota”
Ec
osys
tem
func
tioni
ng
“The benefits people obtain from ecosystems”• “Provisioning Services”
• Ecosystem goods• Food, wood and fibre, biofuels, pharmaceutical products,
genetic resources, clean water, ...
© Firnhaber Ec
osys
tem
serv
ices
“The benefits people obtain from ecosystems”• “Regulating Services”
• Protection against flooding and erosion, pollination, water purification, climate regulation, disease regulation, ...
Ec
osys
tem
serv
ices
“The benefits people obtain from ecosystems”• “Cultural Services”
• Spiritual and aesthetic values, recreation, tourism, science, …
Ec
osys
tem
serv
ices
Outline• Biodiversity is threatened by climate change, threatening in
turn many of the ecosystem services that maintain our lives and the functioning of the biosphere.
• The changes and impacts are here to stay. They are not predictions or remote, future scenarios
Outline• Species, the bricks of biodiversity, can be seen as alternative
solutions to changing challenges. • Biodiversity also encapsulates the notion of intraspecific
variability and population differentiation so the portfolio of responses includes a range of alternatives on local adaptation and plasticity that we are just beginning to uncover.
Outline• Political, economical and social implications far beyond the
ecological functioning of our planet
Outline• Political, economical and social implications far beyond the
ecological functioning of our planet
Regresando a la biodiversidad…
• High biodiversity ensures ecosystem stability in face of environmental changes, becausesome species are able to resist to disturbances,the loss of some species and their functions might be
compensated by others,species can adapt to environmental changes.
Analogy to economics: the portfolio effectlong-standing principle in economics that more diversified
portfolios are less volatile, because the sum of many items is less variable than the average item.
Insurance function of biodiversity
Niche complementarity Each species plays a specific role in the ecosystem
(has its own niche)In sum they are more efficient than each individual species
Analysing large datasets: forest inventuries• Positive diversity-production relationship
Caspersen & Pacala 2001 Ecological Research Vilà et al. 2007 Ecology Letters
Tree diversity
Science 14 October vol 354
Science 14 October vol 354
• the opposite to be true – a decline in biodiversity would result in an accelerating decline in forest productivity.
Science 14 October vol 354
• Scientists from 90 institutions consolidated field-based data forming one of the largest global forest inventory databases in the history of forestry research.
• Tens of thousands of forestry professionals collected the underpinning data, which extended over a period of 150 years.
• In total, data was collected from more than 770,000 plots consisting of more than 30 million trees across more than 8,700 species.
• The study took into account all major global forest ecosystems across 44 countries and territories. It included some of the most distinct forest conditions on Earth, such as the northernmost in Siberia; the southernmost in Patagonia; the coldest in Oimyakon, Russia; the warmest in Palau, an archipelago in the western Pacific Ocean; and the most diverse in Bahia, Brazil
Science 14 October vol 354
Science 14 October vol 354
As forests go, so goes the economy
• Researchers calculated that the amount of loss in productivity that is associated with the loss of tree species richness would have an economic value of up to a $500 billion per year across the world.
• That amounts to more than double what it would cost to implement effective conservation for all of Earth’s ecosystems on a global scale.
• The strongest economic message of this study is that the economic benefit of forest species diversity far exceeds the cost of preserving it, even when we only consider its role in maintaining the global commercial productivity of forests.
Science 14 October vol 354
The ongoing species loss in global forests could substantially reduce forest productivity, thereby reducing the absorption of carbon dioxide by forests from the atmosphere.
Therefore, conserving forest biodiversity should be one of the important actions on what we can do about climate change.
Science 14 October vol 354
Multifunctionality
Nature Communications March 2016
Nature Communications March 2016
Multifunctionality increases with biodiversity
Science November 2016
Science November 2016
Science November 2016
Science November 2016
Science November 2016
Cascadas ecológicas
An ecological cascade effect is a series of secondary extinctions that is triggered by the primary extinction of a key species in an ecosystem.
An example: cascade effect caused by the loss of a top predator (sea otters, Enhydra lutris).
Cascadas ecológicas
The loss of a top predator (sea otters, Enhydra lutris).
Starting before the 17th century and not phased out until 1911, sea otters were hunted aggressively for their pelts, which caused a cascade effect through the kelp forest ecosystems along the Pacific Coast of North America.
One of the sea otters’ primary food sources is the sea urchin (Echinoidea), which experienced an ecological release. The sea urchins then overexploited their main food source, kelp, creating urchin barrens where no life exists.
No longer having food to eat, the sea urchins populations became locally extinct as well. The loss of the kelp ultimately caused their extinction.
Cascadas ecológicas
Extinciones debido a desaparición o introducción de especie clave
Cascadas tróficas o cascadas de extinción
Cascadas ecológicasen sentido mas amplio
Cascadas ecológicas y cambio global
EL CAMBIO CLIMATICO NO VIENE SOLO
• Inviernos cálidos como el actual favorecen insectos que contagian enfermedades tropicales
• La globalización y el cambio climático las han extendido al hemisferio norte.
Enfermedades de la globalizacion
Juniperus thurifera formations, a forest from continental dry
zones
The world upside-down: de-fragmenting landscapes
Land abandonment expanding
forests
1957
20071997
1985
¿Who is moving the seeds and expanding the forest?
This is still a very open research in our group… … it involves many disciplines
Escribano, Escudero Valladares 2011, 2012, 2013; Pias Valladares 2012
Results
Complex patterns resulting from interactions and feedbacks among environmental drivers
Differences at different spatial and temporal scales
Conclusiones 1. Las amenazas a la biodiversidad son en realidad
amenazas a nuestro propio bienestar
2. La biodiversidad encapsula muchos conceptos, mas alla de la riqueza de especies: variabilidad genética, estructura de poblaciones, relaciones interespecificas
3. La biodiversidad es la base para la multifuncionalidad de los ecosistemas y el mejor seguro ante cambios ambientales importantes
Biodiversidad comenzando a entender su importancia en un mundo cambiante....