Quotes that stick. #INT13

I'm back in Toronto now, and here are some quotes from talks that have really stuck with me. INTECOL was a great meeting, it was very interesting to hear about all the research from around the world. I hope all the attendees had a great time.

Sandra Diaz: “We just don't know enough to understand how functional diversity links to environmental change and ecosystem services.”

Erika Edwards: “big phylogeny, big trait data set analyses leave me feeling a little empty”

Erika Edwards: “carbon economy is part of the whole organism, not single traits.”

Joel Cohen: “Mathematics is like sex, you can talk about it but you shouldn't do it in public.”

Enrique Chaneton, Describing what happen during a study looking at the effects of grazing on ecosystem decomposition rates: “A volcano erupted during the study and sometimes shit happens, ….. the volcano killed many of the cattle.”

Carsten Meyer, Talking about global data availability in large databases: “Countries that under report are large emerging economies (china, India, Brazil, Russia) which could finance these efforts but for some reason do not.”

Ove Hoegh-Guldberg, ‘To get change we need to reach more than the brain, but the human heart”

INTECOL & the future of community ecology for infectious diseases – August 21st 2013 - #INT13

This year's conference has a strong focus on infectious disease which included today's symposium Community ecology for infectious diseases organized by Joanne Lello.

Throughout the symposium a great deal of interesting questions related to host-parasite interactions being addressed with a diverse set of methods ranging from the mathematical biology of Andy Dobson, to the experimental C. elegans / pathogenic bacteria systems of Olivier Restif and Gregg Hurst, the wild rodent systems of Heike Lutermann, Andy Fenton, and Owen Petchey, and the next generation molecular techniques employed by Serge Morand.

However, it was Robert Poulin the keynote speaker who set the theme of the symposium to which many of the speakers kept returning: What are the future directions of parasite community ecology? Dr. Poulin began the session with an overview of the recent trends in parasite ecology over the last few decades and Lawton's view that community ecology is a mess (Oikos 1999 – 84: 177-192). The initial research done on host-parasite interactions was centred within the one host – one parasite framework, often dealing solely with the effect of the parasite on its host. This was then expanded to the one host – multi-parasite level, often investigating drivers of parasite species richness among hosts via comparative analyses and occasionally extending to parasite-parasite interactions though the use of null models. Although the data were available beforehand, only recently has the field moved into the domain of multi-host – multi-parasite interactions, now focusing on questions of infection dilution, meta-analyses of parasite richness, and describing the networks of interactions within these communities.

Looking ahead into the future of this discipline, Poulin suggested that researchers should expand beyond simple topological networks of associations to include the strength of interactions, potentially via energy flow, and the use of network analyses on smaller scales using individual hosts. Serge Morand also highlighted the need to develop and incorporate parasite phylogenies into these multi-host - multi-parasite communities. His talk highlighted recent advances in next generation sqeuenceing and how these techniques can be applied to parasite communities. One obvious advantage is that through molecular phylogenetics researchers will be able to define and quantify a higher degree of parasite diversity, but additionally molecular markers can be used to uncover unexpected host diversity or identify species that may be difficult to distinguish through traditional taxonomic keys. Morand continued to press the application of new techniques in immunogenetics and the integration of methods in molecular epidemiology with the theory of transmission and community ecology.

Finally Andy Dobson posited that in addition to pressing forward with our research into infectious disease, it is imperative that contemporary researchers revist the “best hits” of the past and address important issues that have fallen to the wayside. Primarily Dobson pointed out that mathematically, aggregation and virulence of parasites have been shown as important factors for determining parasite co-existence. However, the concept of aggregation is often left out of contemporary discussions although it will be important to determine natural forms of the aggregation distribution and also to attempt to make the link between immunity and aggregation of parasites in a multi-host – multi-parasite community.

Whether incorporating novel molecular and statistical techniques, exploring previously unstudied model systems, or revisiting the context of contemporary research, it is clear that community ecology and infectious disease has a promising future and that it has progressed greatly from the mess Lawton made it out to be in 1999.

INTECOL day 2: Plenaries to rock you. #INT13

Today I had a number of journal related obligations (for the Journal of Applied Ecology -which is celebrating its 50th anniversary here at the conference) and I had time to attend just a few talks. I saw some great talks -especially by Tad Fukami on evolutionary priority effects, but I decided to only post my (inadequate) notes about two of the plenary talks today. They were great talks, and both of them really expanded my perception of human-caused effects on natural systems, in very different types of habitats. 

Ove Hoegh-Guldberg. Corals reefs and global climate change. Coral reefs occupy less that one percent of ocean area but one in four fish caught come from reefs, supporting 400 million people. In the Caribbean coral cover has drastically declined from 80 percent cover to about 10 percent. This has happened elsewhere too, Asia and Australia. In Australia, where coral reefs are well protected and financed, they are still declining. Human development, pollution from agriculture and over harvesting are the common local causes, but global warming and ocean acidification are major global changes. Marine systems are greatly warming, more than land, but very few studies in marine systems. Increases in sea temperature can result in mass coral bleaching and death of corals. Major bleaching events over the past two decades, killing significant proportions of coral. Even though temperature is the best predictor of bleaching, mortality is more variable and other factors may help corals recovery, and these other factors are what managers can influence. In the coming decades, warming temperatures will mean common widespread bleaching events, with some areas becoming too warm for corals. Based on large mesocosms that track local ocean temperature and co2 concentrations. With warming, the mesocosm reefs change into algal dominated systems, with fewer other types of species (e.g., sea cucumbers). Two scenarios to deal with climate change -mitigate or adapt. We need to mitigate within twenty years, reduce co2 emissions. To get change we need reach more than the brain, but the human heart. Partnered with Google to have street view for reefs (this is completely awesome -check it out here). This initiative is both science (mapping reefs) and important outreach, letting people experience diving. One billion people have visited with almost two million people 'dived' in the first week.

Nancy Grimm. Water systems in urban habitats. Populations around the world are moving to cities, and projections have over 650 cities with over a million people by 2025. Creates multiple stressors in urban ecosystems, and there is a new need to build knowledge capacity. Large proportions of people already live in urban areas with limited water supply, quality and delivery capacity. Eighty percent of the population lives in areas under threat of water scarcity, but some people have access to technological solutions that minimize this (e.g., arid USA). For others, ecological knowledge may help reduce this threat. Areas around the world are experiencing more heavy rainfall and flooding. The way municipalities deal with storm water is building hard channels and surfaces, but building ecological systems can better handle water and pollution. In the arid southwest, there are opportunities to retain storm water in semi-natural systems. Provides ecosystem services and denitrification.

Sorry for the brevity of the talk summaries -I'm working on a very full schedule!

INTECOL day 1: A day full of ecosystems #INT13

Note: These are some thoughts from the first day of INTECOL. –Sorry for the abruptness and lack of polish on these entries, there were many talks and I have little time for a proper composition.

*acronyms: BEF = Biodiversity and Ecosystem Function; GBIF = Global Biodiversity Information Facility

It is clear to me that INTECOL is the premiere ecological meeting. There are delegates from countries all over the world from 67 countries , with especially strong European contingents. The next INTECOL meeting will be in Beijing in 2017. This is a special INTECOL as this is the 100th anniversary of the British Ecological Society. The opening talk by Sandra Diaz was held in an immense auditorium at the ExCeL centre, with a couple of thousand in attendance.

Morning plenary:

Sandra Diaz: functional traits are at the core for understanding changes in biodiversity and how species contribute to ecosystem function. Theophrastus, Greek philosophers, created first functional groups. Looks at key traits for tens of thousands of species, only possible through TRY data base. Most variation explained by size ( height, seeds, etc.), second was leaf economy ( leaf N, Leaf area, etc). These traits define plant functional design. Densities low on the fringes of this trait space -physical challenges, and many of these species use human help for success (crops and weeds). Two dense areas in the trait space -big slow growing trees, and small species. Effect and response traits are important for linking environmental change to ecosystem services. These traits can be linked or decoupled, and could change management options.

Linking trait dispersion and values to ecosystem function is a new area, and so few studies. We just don't know enough to understand how functional diversity links to environmental change and ecosystem services.

 Sandra Diaz giving her plenary lecture

Tree of life in ecosystems symposium:

Lisa Donovan: how selective pressures influence evolution of biogeochemical cycling. Traits appear evolutionary labile, and reported on a common garden experiment to find genetic differences controlling traits. Nitrogen has phylogenetic signal but few differences between close relatives. Major differentiation within species and especially for different agricultural lines.

Erika Edwards: Need to move down to small scale to truly understand the evolution of traits that affect ecosystem function. She looks at the genus Viburnum. Need to think about whole organism traits. E.g., branching and growth pattern. This originates from tropics and reinvaded temperate regions repeatedly, and a mix of different and similar strategies emerged. growth patterns highly conserved, but leaf spectrum traits were not. Flowering time seems linked to carbon economy traits.

Amy Zanne: Evolution and biogeography of leaf and stem traits. Angiosperms originated in the tropics and understory woody species and spread everywhere and all types of morphologies. Most species are woody and not exposed to freezing, and lineages move back and forth in climate species but less so with growth form. lineages shift growth form first, followed by climate changes.

Cornwell. Evolution of decomposition. Differences in decomposition rates among different phylogenetic lineages. Did plant life go from fast cycling world to slow one during evolution. Experiment in common garden for decomposition rates. basal angiosperms (magnolias) has lower decomposition than eudicots, which has fast decomposition rates.

Afternoon plenary:

Joel Cohen. Taylor's law after half a century. Taylor's law has been verified but we don't understand it. Taylor's law states that the variance of a population is positively related to the mean population size. Further mean population size is correlated with body size. He showed that tree data supports a body size-variance relationship. Does it apply to food webs? Data from aquatic systems show this pattern across species. Why do we care about Taylor's law? Used for understanding fluctuations in epidemiology, conservation of endangered species and management of forestry resources. Can see the same variance-mean relationships in nonbiological data -computer data packets, weather data and stock market trades. No underlaying theory to explains these. Previous attempts, such as affects of competition, do not seem to affect pattern.

Biodiversity & Ecosystem function session:

Enrique Chaneton. Movement of large herbivores around the world, introduction of cattle versus reintroducing native extirpated herbivores. Little is know how these large herbivores influence forests. Multiple pathways of effect from changing plant composition and waste excretion, affects decomposition. Within an Argentinean park, sites on lake islands do not have introduced herbivores and compared to nearby mainland sites. Herbivores reduce vegetation cover by sixty percent. Trees and shrubs were particularly affected. Distinct composition shifts. Litter layer was substantially different. In dry sites, higher decomposition in ungrazed sites. Volcanic eruption during research 'sometimes shit happens' killed many of the cattle.

Carsten Meyer. Examined the completeness of species point data inventories. Looked at GBIF records and compare to known distribution maps. GBIF records are highly biased to North America, Europe and Australia. Species rich areas are almost absent from GBIF records. Not adequate for research or conservation. Funding, accessibility and human safety all at play for biases. These factors seem to differ among taxonomy, interestingly. Countries that under report are large emerging economies (china, India, Brazil, Russia) which could finance these efforts but for some reason do not.

Julia Koricheva. Tree species richness and genetic diversity on leaf miners. What is the relative importance of these two effects. Two experiments, one manipulating tree richness -up to five species, and another with up to eight clones of silver birch. Silver birch was in both experiments, so was the focus of leaf miner surveys. Tree richness affects miner richness, but not abundance. More leaf miner species with higher tree richness in first year, but not second. For genetic diversity, miner richness also increased with number of clones. Looked at effect sizes of two experiments and genetic diversity appeared to have a stronger effect on leaf miner richness.

Tommaso Jucker. Complementarity in functional groups enhances wood production. He noticed that there were eighty talks on BEF at INTECOL. Four species combinations two pines and two oaks. Biomass increased with richness, but looked at more detail, growth over the past ten years from wood cores. Both pines grew much better in mixture, but oaks only increase growth when other oak is present. Tree that benefit the most are small trees. For pines, wet year showed largest increase in growth, most room for complementarity.

Eric Allen. Direct and indirect effects of landuse on multifunctionality. Landuse intensity changes functions, it increases biomass but reduces bird diversity, flower cover, increases pathogens, etc. Used path analysis to compare landuse and biodiveristy as well as environmental variables. from this analysis, plant richness seems negatively correlated with multifunctionality. looked at groups of functions (e.g., production, soils, cultural). some plots shows strong indirect effects of richness for some functions.

Siobhan Vye. Responses to multiple stressor change. Examined stressors in coastal systems. Looked at how an invasive species affected community response to stress by experimentally combining species in mesocosms and manipulated nutrient enrichment and temperature. Invader increases productivity. The presence of the invader determined how the stressor influenced community functions.

Sebastian Meyer. BEF changes over time. A number of studies show that BEF experiments increase in strength over time. Examined how functions change over time using Jena experiment. How many different functions show changes over time? Over half of functions are influenced by diversity generally. He regressed the richness-function slopes across time, and about one third of functions showed increasing diversity effects over time. What are the mehanisms? The stronger relationships are driven by a combination of changes in high diversity treatments and changes in low diversity treatments.