Sarah Amundrud (PhD Student)
Research on ecological effects of climate change has traditionally focused on direct, physiological effects on species; however, we are beginning to recognize its potential to alter ecological communities and ecosystem processes indirectly, by affecting species interactions. Foundation and keystone species exert particularly strong effect on communities, and thus present a high potential to mediate ecological effects of climate change. In Monteverde, Costa Rica, water-filled bromeliads provide habitats (i.e. are foundation species) for diverse invertebrate food webs and occur along a climate (elevation) gradient. The keystone predator (damselfly-larvae) is absent from bromeliads in the relatively cool and wet high elevation bromeliads. Thus, these miniature ecosystems are ideal systems to examine the relative importance of direct and indirect ecological effects of climate change. I am combining observational, experimental, and modeling techniques to tease apart which factors best explain community composition: climate; habitat; or predators. Moreover, I use modeling techniques to predict community and ecosystem changes under future climate scenarios.
Gustavo Cauê (PhD Student, UNICAMP)
Gustavo is co-advised by
and Diane Srivastava
Interested in the effects of cross-ecosystem trophic cascades, particularly the magnitude effects
of predators living in land-water boundaries on aquatic ecosystem functioning.
Melissa Guzman (PhD Student)
Dispersal is an important mechanism in structuring community composition at regional scales.
It can increase population ranges, prevent local extinction and increase the genetic pool for
adaptation. The aquatic invertebrate community in bromeliads create food webs where they disperse
from one bromeliad to the next forming metacommunities. I am interested in understanding the role
of dispersal in food webs and how it structures a community at different scales. For this I'm
going to do a series of experiments and models. I will estimate dispersal distances using a NGS approach.
Ana Z. Gonçalvez (PhD Student, UNICAMP)
Ana is co-advised by
and Diane Srivastava
Different predator ants can construct their nests in tank bromeliads and they can
alter the composition and species diversity in these micro-ecosystems through the predation
behavior. Depending on the behavior of the ants, they can have different effects on the species
composition in the bromeliads and alter the food chains, causing trophic cascades between the
terrestrial and aquatic ecosystems. Furthermore, they can also alter ecosystem processes
(e.g., nutrient cycling and its availability to plants). In this context, I am interested
in the influence of different predator ants on the nutrition and development of their host
bromeliads and how they alter the terrestrial and aquatic biota in these plants.
Nicholás Marino (PhD Student, UFRJ)
Nicholas is co-advised by
and Diane Srivastava
Climate change is an ongoing process that is already affecting several parts of the Earth. Ecological
and evolutionary studies on the impacts of climate change traditionally focus on ecosystem and
community-wide impacts of changes in temperature. However, changes in the precipitation regime are
also predicted to occur - increasing the sensitivity of aquatic habitats to climate change. Moreover,
some key direct (i.e. density mediated) and indirect (i.e. trait-mediated) species interactions,
such as predation, may be disrupted or lost, amplifying the impact of climate change. Using
tank-bromeliads as a model-system, I am interested in understanding how changes in precipitation
can affect the consumptive and behavioural roles of predation in aquatic ecosystems.
Pierre Rogy (MSc Student)
The citrus greening disease is a bacterial field disease affecting citrus trees and spread by
the jumping plant louse Diaphorina citri
. It greatly reduces the lifespan of trees and
makes the fruit unusable, causing substantial economic impacts. Biological control can be
an efficient disease management strategy, and is already implemented in various
orange orchards. If bromeliads are present in orchards, bromeliad-associated predators, such as
ants, scorpions and spiders, and the biological control agents would compete for the same lice.
However, the impacts of predation efficiency of several predators targeting the same prey item
is highly context-specific and poorly understood. Thus, I am interested in assessing whether those
predators can be used as a supplement to biological control in a synergistic relationship, which
could have important consequences in terms of ecosystem services and pest management.
Natalie Westwood (PhD Student)
Forest fragmentation is a common problem that affects many landscapes, especially in the neotropics.
This can lead to changes in how food webs are constructed, and consequently may change ecosystem processes
in these communities. I am interested in understand how top-down and bottom-up controls on a community may
affect the community composition and the ability for that community to function. I will also work to understand
how these controls may differ in the context of forest fragmentation. In order to test this I will manipulate
aquatic treehole communities in both fragmented and intact forest to determine the effects of both types of controls.