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Understanding Change in Biodiversity and Consequences for Ecosystem Function
University College London, 4th April 2017, 10 AM – 5 PM
FINDING THE SYMPOSIUM
The symposium is being held in the Anatomy Building at UCL (http://www.ucl.ac.uk/maps/anatomy-building), in
the J Z Young Lecture Theatre. Enter through the main entrance of the Anatomy Building, and there will be a
delegate list at reception. The lecture theatre is just behind the reception.
SESSION 1: ECOSYSTEM FUNCTION AND ECOSYSTEM SERVICES (CHAIR: TIM NEWBOLD)
10.00 Amanda Bates: Functional shifts in rocky reef communities with warming depend on protection from
exploitation and range extension by a habitat-altering urchin
Shifts in the abundance and location of species with warming have been documented from the tropics to the
poles. Given that such shifts lead to community restructuring with the potential for changes in trophic
interactions, it is presently unknown whether habitat protection will promote resilience to global change drivers
including warming and invasive species. We take advantage of a natural experiment to test for biodiversity
responses in protected and fished temperate reef communities in southeast Australia that have been regularly
surveyed over a 21 year period. During this observation window, the region has undergone rapid warming and
colonization by a range-extending urchin (Centrostephanus rodgersii) that grazes macroalgal beds and forms
extensive rock barrens. We used a generalized additive mixed-effects modelling approach o contrast responses in
the community thermal index (CTI, the average realized temperature niche for all species present), invasion
status, and different functional groups (trophic level: animals and structural group: algae) at sites with and
without protection. Overall, a regional tropicalization has occurred in the brown macroalgae and fishes,
particularly so in the sessile invertebrates, detected as an increase in the CTI. The tropicalization signal is due to
increases in the local richness and abundance of warm-affinity species, and with increases in the urchin.
Protection from fishing, however, strongly influenced the structure of these transitional communities, including
colonization by the urchin. Protected communities are distinguished by gaining canopy-forming algae and
resisting colonization by small foliose algae, low trophic level warm-water fishes and the urchin. By contrast,
herbivorous and omnivorous invertebrates have declined in protected areas and communities where carnivorous
fishes and lobsters are most abundant. Our findings thus implicate the role of biological interactions in affecting
how communities transition with warming, and highlight the potential for predation to not only decelerate range
expansions, but also accelerate range contractions.
10.15 Felix Eigenbrod: A spatially explicit socio-ecological framework for predicting the effects of landscape
structure on ecosystem services
Understanding the effects of landscape structure (composition and configuration) on ecosystem services (ES) is
vital for their sustainable management. Predicting the effects of landscape structure on ES is more challenging
than predicting the effects of landscape structure on biodiversity due to the coupled socio-ecological nature of ES.
Here, we present an integrative spatially explicit modelling framework that extends John Wien's classical focal
patch for predicting the effects of spatial structure on biodiversity to ecosystem services. The central tenet of our
framework is that predictive modelling of ES should explicitly consider the spatial scale at which each relevant
social and ecological predictors should be measured. In other words, we argue that the key to predictive
modelling of ES is to recognize each predictor of the distribution of a given ES has a spatial scale that is most
appropriate for assessing its role in determining the distribution of an ES, including relevant components of
landscape structure. This approach differs somewhat from most ES modelling frameworks in which predictor
variables are assigned to a common scale of analysis. A major benefit of our approach is that it means that the
relative contribution of landscape structure on the distributions relative to other predictors can be quantified for
a given ES in a given socio-ecological context. Moreover, we hypothesize that a clear understanding of the degree
to which the most important spatial scale of different socio-ecological predictors of different ES varies by location
will greatly improve the predictive power of spatial models of ES.
10.30 Andy Hector: Biodiversity and ecosystem functioning: From local to landscape
Two decades of intensive experimental research have led to consensus that the biodiversity of an ecosystem can
influence its functioning and that loss of diversity is usually detrimental. One of the current challenges is to
investigate whether these experimental results apply in real-world settings and how they extend to landscape
scales. We present new results from a global analysis of the links between alpha and beta diversity and ecosystem
multifunctionality in grassland ecosystems using data from the worldwide Nutrient Network.
10.45 Axel Rossberg: How loss of fish biodiversity affects marine ecosystem functioning
Biodiversity-ecosystem functioning (BEF) relationships for fish in large marine ecosystems are difficult to measure.
Experiments are ethically prohibitive. Using the world's taxonomically most highly resolved marine food-web
model, we therefore obtained quantitative BEF relations from simulated extinction and exploitation experiments
(doi:10.1038/ncomms7657). Remarkably, we find that the main interaction shaping the BEF curve, i.e. making it
different from a straight line, is not competitive release of the remaining species, as is the case for plant
communities, but release from predation. Thus, even though the BEF curves we find for marine fish tend to have
saturating forms similar to those known from experiments with plants (with variations depending on the order of
extinction), the underlying mechanism is entirely different. We find the reason for this to be that competition of
plants for limiting resources leads to approximately symmetric competitive interactions, while indirect
interactions among fish by feeding on the underlying complex, structurally unstable food-web of phytoplankton
and zoo-plankton can lead to any kind of sign structure for the resulting effective interaction pattern for pairs of
fish species. Based on this understanding, we expect similar phenomena for other high-trophic-level functional
groups, casting doubt on the transferability of results from simple experiments or simulations with only one or
two trophic levels to biodiversity at large.
11.00 Discussion
11.30 Coffee break
SESSION 2: PREDICTING CHANGE (CHAIR: ANDY PURVIS)
11.50 Adriana De Palma: PREDICTS models: from species to function and space to time
12.05 Tim Newbold
12.20 Kate Jones: Predicting global emergence and spread of zoonotic diseases
Human infectious diseases are a significant threat to global human health and economies (e.g. Ebola, SARs), with
the majority of infectious diseases having an animal source (zoonotic). Despite their importance, the lack of a
quantitative predictive framework hampers our understanding of how spillovers of zoonotic infectious diseases
into the human population will be impacted by global environmental stressors. Although empirical statistical
analyses of human infectious diseases have been successful in understanding the spatial environmental correlates
of initial outbreaks, a mechanistic understanding of these patterns is lacking at a global scale. Here I present some
latest research attempting to merge both empirical and mechanistic approaches at a global scale using data from
a poorly understood disease, Lassa fever. I show that macro-scale environmental conditions play an important
role in driving the spatial extent of Lassa virus and that any future habitat change to agricultural systems may
facilitate a range expansion. I also expand this approach to model zoonotic diseases more generally and examine
the impact of future environmental and habitat change on the emergence and spread of zoonotic diseases.
12.35 Discussion
13.00 Lunch break
SESSION 3: CHANGE AT THE LEVEL OF ECOSYSTEMS (CHAIR: ADRIANA DE PALMA)
14.00 Nathalie Pettorrelli: Ecosystem functions monitoring: opportunities, challenges and way forward
Societal, economic and scientific interests in knowing where biodiversity is, how it is faring and what can be done
to efficiently mitigate further biodiversity loss and the associated loss of ecosystem services are at an all-time
high. So far, however, biodiversity monitoring has primarily been focused on structural and compositional
features of ecosystems despite growing evidence that ecosystem functions are key to elucidating the mechanisms
through which biological diversity generates services to humanity. This monitoring gap can be traced to the
current lack of consensus on what exactly ecosystem functions are and how to track them at scales beyond the
site level. I will here present recent advances made by the GEO BON Ecosystem Function working group to
develop a global biodiversity monitoring strategy for ecosystem functions, and discuss current challenges and
opportunities.
14.15 Peter Verburg: Land use change: global and regional impacts on biodiversity and ecosystem functioning
Land use change encompasses a wide range of different processes ranging from urbanization to agricultural
intensification. While most land use changes are seen as a threat to biodiversity and the provisioning of
ecosystem services, there are also opportunities. Large scale land abandonment and restoration can release
pressures on fragmented natural areas. During the talk I will present the way in which land use models and
prioritization tools can be used to explore the role of different land change trajectories and inform the planning of
strategies for conservation of biodiversity and ecosystem services. I will show how spatially explicit analysis allows
for the consideration of tradeoffs and the consideration of specific, regional, challenges.
14.30 Cristina Banks-Leite: Intertwined nature: how the making of a community transforms ecosystems
In this talk, I will first show how plants, invertebrates, amphibians, birds and mammals are severely impacted by
habitat loss and fragmentation in the Atlantic Forest of Brazil. I will then discuss how the use of phylogenies, traits
and field experiments can help us better understand the functions that species perform, and the consequences of
biodiversity loss to ecosystem functioning.
14.45 Michelle Jackson: Impacts of global warming in freshwaters: from genes to ecosystems
With accelerating rates of global warming, it is becoming increasingly important to understand the full range of
effects elevated temperatures have on ecosystems. Past research efforts on climate change have focused on
individuals or populations, but there has been an expanding emphasis on communities, networks, and whole
ecosystems, often providing insight which is only available at this scale. Here I will present preliminary results of
the NERC funded ‘Ring of Fire Project’ which is quantifying the impacts of warming in freshwater ecosystems in
the Arctic using a genes to whole ecosystem approach. These ecosystems can act as sentinels of change because
warming is predicted to be especially rapid at higher latitudes, and freshwaters are particular vulnerable to
multiple climate stressors. We use five geothermally heated regions (Iceland, Alaska, Greenland, Kamchatka and
Svalbard) as natural laboratories with 60 streams ranging in temperature from 2 to 50oC. These natural
laboratories provide the ideal systems to address grand challenges in global change ecology.
15.00 Discussion
15.30 Tea break
SESSION 4: POSTERS
15.50 Poster presentations (with wine & nibbles)
[Poster] Elizabeth Boakes
[Poster] Rodrigo Cámara-Leret: Setting conservation priorities in Indonesian New Guinea
New Guinea is the most mountainous and most biodiverse island in the world. Nearly 50% of its 16,000 plant
species are endemic and in some families endemism surpasses 70%. Accordingly, understanding how biodiversity
is distributed across the island, and how it will cope with increasing land use change and predicted climate change
is important for coordinated conservation actions. However, New Guinea remains under-collected and little is
known about the geography of endemism and extinction threat. New Guinea is at risk of logging and oil palm
development, especially in the flat lowland regions. Past work has focused mostly on the eastern Papua New
Guinea side, whereas the western Indonesian sector of the island, including its West Papua province still remains
poorly studied. Despite the West Papuan governor and the heads of 12 West Papuan regions declaring West
Papua as Indonesia’s first official Conservation Province in October 2015, West Papua has yet to employ an
evidence-base approach to demarcating conservation areas and measuring complementarity between areas.
Large-scale syntheses are thus essential for setting island-wide conservation priorities, and for evaluating the
performance of protected areas under land use and climate change.
[Poster] Friederike Clever: Local and Regional Patterns in Fish Community Structure on the Mesoamerican
Barrier Reef
The importance of coral reefs as centres of biodiversity is well recognised; however, the scale at which specific
structures relate to fish diversity patterns remains poorly explored. This study investigates the relative
importance of geomorphological reef zones versus entire reef systems in explaining fish communities across three
isolated but degraded Caribbean atolls. We compared shallow water (< 6 m) reef fish communities at 93 sites
among and within atolls and across five geomorphological reef zones to assess their relative effects on both
taxonomic and functional fish diversity. Reef zone explained higher variation in fish communities than atolls;
however, taking into account functional traits revealed differences in fish communities among atolls. While reef
zones retained a high proportion of the overall functional niche breadth suggesting high functional redundancy in
fish communities, most individual trait combinations comprised only few species. Thus, our results indicate high
vulnerability to functional loss in Caribbean coral reef fish communities, which agrees with previous findings from
research conducted on larger spatial scales. We show that combining geomorphology with functional metrics aids
detecting differences fish diversity patterns crucial to conservation and fisheries management. Furthermore, our
findings are relevant to the challenge of detecting environmental change-induced community shifts in these
important ecosystems.
[Poster] Rory Gibb: Projected future trends in Lassa fever, agriculture and carbon storage in West Africa
Anthropogenic processes such as land use and climate change are important drivers of many zoonotic and vectorborne diseases. Disease regulation is therefore often framed as an ecosystem service (ES) impacted by changes to
ecosystem function and biodiversity (the One Health concept). However, quantitative disease predictions are
rarely incorporated into future ES projections, despite the clear need for a fuller understanding of human health
impacts of land use and conservation decisions. Here, we apply a recently developed environmental-mechanistic
epidemiological model and methods for mapping ES proxies, in order to predict future changes to human Lassa
fever, agricultural land use and carbon storage across a gradient of projected land use change in West Africa.
Lassa fever is an important neglected viral zoonosis with a high endemic health burden, whose rodent reservoir
host is closely associated with agriculture and rural livelihoods. We develop a projected gradient of 2070 landcover-land-use rasters (from low to high intensity of change) by simulating forward from present-day data (20012011). Projected change is dominated by conversion of savannah and forest to cultivated land, expanding suitable
habitat area for the Lassa reservoir host. This agricultural expansion is predicted to drive both losses of stored
carbon in vegetation and a small increase in human Lassa cases. Human population growth and climate change
then act as major drivers of disease, with predicted Lassa cases more than doubling by 2070. While preliminary,
our results indicate that incorporating disease regulation into global change and ES projections has potential to
improve understanding of the costs of ecosystem change.
[Poster] Jack Hatfield: Birds in the matrix – the effects of land use conversion and fragmentation on avian
communities
Habitat loss and fragmentation is one of the major threats to tropical biodiversity, where native forest is replaced
by pasture and exotic tree plantations. The influence of these different matrix types upon the community
composition in forest patches is yet to be fully understood, particularly when considering a fragmentation
gradient. We investigate these effects by considering the avifauna of Brazil’s Atlantic Forest – a highly fragmented
biodiversity hotspot. We surveyed bird species with an interior-edge-matrix grid at 50 sites along a fragmentation
gradient. Half of the patches were embedded in a pasture matrix, the other half within Eucalyptus spp. We
examine bird α, β and γ diversity and composition in relation to landscape attributes such as connectivity and
patch size. We have found 248 bird species so far, although fieldwork is ongoing. Preliminary results indicate a
marked difference between the community found in the pasture and Eucalyptus - the latter has lower species
richness but is more similar to forest. The trends observed for the patch interior and edge communities
resembled those found for the matrix, showing the value of native forest cannot be replaced by non-native open
or forested habitats, and that a combination of matrix types is potentially the best overall solution for the
regional avifauna. The study results will provide management implications on how best to maintain the highly
endemic biodiversity of one of the world’s most endangered realms.
[Poster] Hernani Fernandes Magalhães de Oliveira: El Niño induced effects on mutualistic seed dispersal
networks
The frequency of strong El Niño events is expected to increase due to climate change. These events have
contrasting impacts in different world regions; some places become wetter while others become drier. Rainfall is
a key factor influencing plant phenology and primary productivity, and is thus expected to have cascading effects
on networks of interactions among frugivores and the plant species they feed upon. Higher rainfall tends to
produce more modular networks while drier conditions lead to more nested interactions. The El Niño cycle of
2015-2016 was considered one of the strongest on record. In Costa Rica, it caused severe droughts in dry forests
of the Pacific coast, and extreme floods in rainforests of the Atlantic coast. To quantify the impact of extreme
fluctuations in rainfall associated with El Niño on the structure of mutualistic networks, we studied interactions
between frugivorous bats and plants. By applying DNA barcoding to seeds collected from bat guano and pulp, we
constructed mutualistic ecological networks. We then ran null simulations to determine changes in network
properties across the El Niño period, both within and between the dry and rainforest sites. We found that El Niño
led to similar effects on network structure across both forests, but to different effects between seasons within
each habitat. Here we highlight the main consequences of drought and flood conditions during an extreme El
Niño event on the overall structure of mutualistic networks.
[Poster] Katia Sanchez-Ortiz
[Poster] Charlotte Selvey
Agriculture has both dependencies and impacts on biodiversity and ecosystem services, and there is widespread
evidence that intensive agriculture causes significant biodiversity loss and degradation of ecosystem services.
Changes to farm management, for the enhancement of ecosystem services and food production, is becoming
widely discussed within the agricultural and academic worlds. But how much are these services worth in
monetary terms? Previous valuation studies have focussed on the value of pollinators in apple orchards, and
others have valued the pest control service provided by arthropods. My work focusses on the viability of
insectivorous birds providing an economic pest control service to orchards in Herefordhsire. I have measured bird
and butterfly abundance, species richness and diversity on 31 orchards across Herefordshire, across four
management types: Organic, LEAF, Conventional and Integrated Pest Management (IPM). I then conducted a
sentinel prey experiment, using both pastry and plasticine caterpillars, to understand the predation rates on
different management types. Preliminary results so far show no difference in pest moth specceis across
management types and a significantly higher abundance of insectivorous birds in Organic orchards, taking into
account “woody” landscape features.
[Poster] Conor Waldock: Using abundance-temperature relationships to predict trophic restructuring of
warmer reef systems globally
Changing structure of ecological assemblages in response to climate warming may result in changes in trophic
interactions, with associated implications for key ecosystem functions. Studies predicting community functional
change generally predict changes in species richness or in patterns of occurrence via distribution shifts. Changes
in species’ abundances may be more critical to ecological functioning and ubiquitous than changes in species’
occurrences, but are rarely incorporated into ecological models in response to warming. Here we model how
temperature limits species’ abundances across their geographic ranges, characterising ‘realised thermal
performance’ curves for 4340 shallow reef species globally. We use these in combination with data on community
structure from reef sites across the globe to assess potential community-level outcomes of warming on the
trophic structure of reef fishes. Net declines in abundance are predicted for communities across the tropics,
where species have limited thermal safety margins. Trophic restructuring appears more prevalent where there is
net community abundance decline predicted, compared to the few regions of predicted net abundance gain.
Idiosyncratic changes across many ecoregions suggest decoupling of thermal structure and trophic structure in
general.
[Poster] Sarah Whitmee: How can we measure the 'health' of biomes?
Identifying a single planetary boundary for biodiversity has proved challenging. The multifaceted nature of
biodiversity and the range of spatial scales at which biological systems operate, means that we are unlikely to find
a single threshold value or control variable which adequately represents the point at which declines in
biodiversity take us outside 'a safe operating space'. Here, we try to operationalise the concept of biome integrity
- a set of habitat based, regional metrics that represent the integrity and functioning of a given biome, in relation
to the key anthropogenic pressures faced and the fundamental ecological processes which maintain the biome.
Using coral reefs as an example, we describe a suggested framework to identify robust control variables for
measuring biome integrity and the benefits and drawbacks to implementing such a system to capture an accurate
picture of the health of biomes under increasing anthropogenic pressure.
[Poster] Rungtip Wonglersak: Modelling the Functional Responses of Predator-Prey Interactions to Climate
Change
Understanding and predicting the effects of climate change on ecosystems are crucial for conservation policy
implementation. The aims of this study are: 1) to explore the most appropriate model for two main components
of predator-prey functional response, handling time and attack rate, 2) to develop the Madingley Model by
improving the representation of body mass and introducing a representation of temperature into handling time
and attack rate and 3) to investigate the plausible impacts of climate change on African ecosystems using the
developed Madingley Model. The Madingley Model is a novel general ecosystem model. The model currently
predicts the impacts of climate change on ecosystems through metabolic rate. However, climate change can
affect ecosystems in other ways, for instance, feeding rates of predators. Literature about the impacts of
temperature, predator and prey body mass on handling time and attack rate was searched; data from relevant
papers were extracted. These data were analysed using mixed-effects models to select the most appropriate
model. New temperature-dependence parameters and updated body-mass-dependence parameter values were
incorporated into the original Madingley Model. The new model was used to predict the effects of increasing
temperature on African ecosystems. The model prediction showed that increasing temperature has little effect on
African ecosystems possibly because of the compensation of metabolic activity to feeding activity.