* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Response Diversity
Island restoration wikipedia , lookup
Community fingerprinting wikipedia , lookup
Theoretical ecology wikipedia , lookup
Human impact on the nitrogen cycle wikipedia , lookup
Molecular ecology wikipedia , lookup
Restoration ecology wikipedia , lookup
Habitat conservation wikipedia , lookup
Biological Dynamics of Forest Fragments Project wikipedia , lookup
Animal genetic resources for food and agriculture wikipedia , lookup
Fauna of Africa wikipedia , lookup
Reconciliation ecology wikipedia , lookup
Operation Wallacea wikipedia , lookup
Tropical Andes wikipedia , lookup
Ecological resilience wikipedia , lookup
Biodiversity action plan wikipedia , lookup
Biodiversity wikipedia , lookup
Latitudinal gradients in species diversity wikipedia , lookup
Response Diversity Monika Gorzelak October 20th 2014 “Nature is not fragile . . . what is fragile are the ecosystems services on which humans depend”. (Levin 1999) Ecosystem resilience Amount of disturbance a system can take without changing states o Ability to reorganize, renew after disturbance o capacity to self-organize o Learning and adaptation Response diversity Definition • Diversity of responses to environmental change among species that contribute to the same ecosystem function • Diversity within functional groups is important to the adaptive capacity of ecosystems; not just species richness Role of Biological Diversity in Ecosystem Resilience Functional diversity Ecologically redundant (eg. Both fungi and bacteria are decomposers) Species diversity eg. Many species of decomposer fungi (may have a range of decomposing ability...example: may differ in optimal temperature) Response diversity Response diversity • How to best illustrate this?? Examples Bother? Disturbance Natural • pulse disturbance Human • Chronic disturbance • Compounded perturbations Response diversity • Is not species richness Response Diversity Example: seed dispersal in tropical forests • Western Polynesia after cyclone • Frugivore species disperse tree seeds • Frugivore flying foxes, the dominante P. tonaganus and D. pacifica declined by 90% whereas P. samoensis declined by only 10%. P. samoensis, previously subdominant, was able to maintain function (seed dispersal) Response Diversity Example: plants in rangelands (Walker et al. 1999) • Rank abundance with fill depicting different function • Dominant species are functionally different • Grazed grass replaced with functional equivalent Response Diversity Example: freshwater detritovores • • • • Stoneflies are sensitive to organic pollution Crustaceans are sensitive to acidification Both break down leaf litter Species richness did not affect leaf breakdown rate, but species identity did. Response Diversity Example: coral reef grazers • Coral reef is made of framework-builders, primary producers, herbivores, predators • Herbivores eat algae which blooms in their absence. Algae eventually kills reef • Sea urchins graze, but are not resilient to disease, get wiped out, algae takes over, dead reef • Sea urchins are not functional Response diversity across scales • Palm seed dispersal across a range of scales – Small rodents 5m (maintains patch of palms) – Tapiers 2km (establishes new palm patches) • With disturbance such as hurricane, some patches may be wiped out, but others will remain to re-populate Response diversity across scales Example: coral reef Response Diversity Other examples? • Can we describe the pine beetle outbreak using this concept? • Other examples? • How do we manage ecosystems with response diversity in mind? Response diversity across scales Coral reef • reduced competition between species that feed at different scales (frequency and distance) • All contribute to the same ecosystem function: eating the algae and preventing a bloom, which would precipitate coral bleaching and death Managing response diversity • Reduce human homogenization of landscapes • Avoid elimination of functional groups (ex. predators) • Consider response diversity to maintain ecosystem buffering capacity, in order to maintain the ecosystem services we rely on • Testable Managing response diversity • More barley cultivars in Finland is not better because they all have similar drought tolerance. Quantifying response diversity construct diversity index (similarity index) and validate with real data. Determine how far are we from resilience (Kahiluoto et al. 2014) Response diversity in Forests • What is the goal? Productivity? Resistance to pest outbreaks (pine beetle)? • What are the critical factors? • How do we estimate the impact? • Can we model responses, validate models?