FAPESP: Victor Saito (PI - UFSCar), Tadeu Siqueira (U Canterbury)

NSF: Bryan Brown (PI - Virginia Tech), Kurt Anderson (UC Riverside), Chris Swan (U. Maryland)

12/2022 - 11/2025

Understanding the organization of biodiversity on Earth has puzzled ecologists and biogeographers for centuries. For a long time, only part of these patterns around the globe was explained by deterministic processes related to environmental filters related to functional traits and biotic interactions, while much of the variation that disobeyed these rules were termed to be rather stochastic (i.e. unpredictable, unknown cause). Improving our understanding of this stochastic variation in community taxonomic, functional and trophic composition is crucial to forecast how nature will respond to global changes and how this will affect ecosystem services for society. In riverine ecosystems, stochasticity should come from multiple sources and vary at multiple spatial scales. At the riverine scale, we predict that headwaters and mainstems should sustain populations with different sizes and dynamics owing to their differences in heterogeneity and habitat size, impacting how demographic events, such as individual dispersal and recolonization scale up to patterns of community composition. At the global scale, differences in climate and seasonality should drive variations in individual metabolism and population life cycles with enhanced stochasticity in warmer and more unpredictable environments. This multiscale variation in the preponderance of stochastic processes should impact the functioning of ecosystems through changes in trophic interactions mediated by species traits and organisms' body size. In order to test these predictions, we will conduct a novel coordinated in-situ spatio-temporal study involving tropical and temperate riverine ecosystems. Our aim is to quantify and understand the relative importance of different sources of stochasticity during community assembly and how this would impact functional aspects of trophic interactions and energetic flows. 

PI: Andros Gianuca (UFRN)

Co-Is:  Victor Saito (UFSCar), Carla Rezende (UFC), Thibault Datry (INRAE) and many others 

1/2024 - 1/2027

Ecosystems experience natural disturbances and anthropogenic impacts that affect biodiversity and ecosystem functioning. When natural disturbances modify anthropogenic impacts, widely used biomonitoring metrics may prove inadequate for accurately assessing ecosystem integrity. Considering the projections of an increase in the proportion of riparian systems subject to the effects of drought and intermittency due to climate change and the growing demand for water for human consumption, this project aims to develop and test the potential of alternative functional approaches to complement the biomonitoring metrics widely used in dynamic rivers. Furthermore, little is known about the ecological and evolutionary mechanisms that determine the functional response of species to stress and its impacts on intermittent river ecosystems. Studies with guppies have demonstrated that rapid evolutionary responses to ecological processes, such as predation, influence ecosystem functioning in perennial rivers. Through a network of collaborators, this project will take an important next step by evaluating whether: (i) the intra- and interspecific functional traits that confer tolerance to intermittency are determined by plasticity and/or evolution; whether (ii) these characteristics can also confer co-tolerance to anthropogenic stressors; and whether (iii) this co-tolerance translates into the stability of ecosystem functions in the face of disturbances. To answer these questions, we will first develop a functional approach with already collected international databases. Afterward, we will conduct eco-evolutionary experiments and similar sampling in northeastern Brazil to test applicability and advance our focus on tropical systems. Thus, we hope to offer appropriate tools that managers can incorporate into biomonitoring routines for intermittent rivers. Furthermore, we hope to revolutionize the understanding of the functioning of tropical intermittent rivers by using an eco-evolutionary approach to better understand the contribution of plasticity and evolution to the functioning and stability of these ecosystems. 

PI: Gustavo Quevedo Romero (UNICAMP)

5/2021 - 5/2026

Inland aquatic ecosystems are particularly vulnerable to climate change because (I) many species in these habitats have limited capabilities to disperse as the environment changes; (II) the temperature and availability of water are dependent on the climate; and (III) many systems are already exposed to several anthropogenic stressors. This project aims to investigate the effects of global climate change (eg, warming, thermal variability, precipitation), predicted for the next decades, on the structure, stability and dynamics of complex trophic networks, as well as on the multifacets of macro biodiversity -invertebrates and microorganisms and consequences for ecosystem functioning. Through field experiments in natural microcosms (e.g., bromeliads) and mesocosms comprising lacustrine organisms, we will manipulate the effects of warming, thermal variability/instability and precipitation in tropical and temperate communities. We will also use latitudinal, altitudinal, and thermal gradients (ie, geothermal streams), as well as their underlying climatic components, as effective natural experiments to investigate and monitor the impact of climate change on (i) trophic network structure and (ii) alpha diversity and taxonomic, functional and phylogenetic beta of aquatic macro- and micro-organism species. 

PI: Victor S. Saito (UFSCar)

Host: Jeremy Piggott (Trinity College Dublin)

2023 

Climate change is driving several modifications to the regimes of watercourses. Droughts, melting of mountain tops, and extreme rain events can all modify the seasonal cycle of water flows, inflicting multiple changes in the functioning of ecosystems. Such changes could influence the delivery of ecosystem services, such as clean water, fisheries, and hydropower, jeopardizing human societies around the world. Our aim is to improve our mechanistic understanding of the role of different types of environmental changes related to climate changes (changes in flow velocity and droughts) on the assembly of stream food webs. This study will be conducted in the Ireland ExStream using the deafult design of 128 mesocosms simulating stream communities. We will manipulate water levels and flow velocity simulating events of drought with a full factorial design. The relative roles of deterministic and stochastic assembly will be made by using a null model approach, where random temporal and spatial beta diversity will be compared with empirically sampled communities.

PI: Gilmar Perbiche Neves (UFSCar)

8/2021 - 8/2023

This project will analyze the taxonomy and ecological attributes of microcrustaceans of the second largest river in the world in terms of water volume and drainage basin, the Congo River in Africa (also kneed as Zaire River), for which zooplankton is unknown. New species will be described and an identification catalog will be produced with illustrations and photographs of microcrustaceans from the Congo River (there is no supporting bibliography for identification). With quantitative data on the density of organisms, ecological attributes will be calculated (abundance, alpha, beta and gamma diversity, equitability), which will be space-time analyzed with univariate and multivariate statistics and correlated with limnological variables measured at each sampling site. Five initial hypotheses will be tested. We will describe the zooplankton diversity along the analyzed section, verifying changes especially after the entrance of large tributaries of black or muddy waters and lakes, as well as between the high and low water phases. It is assumed that the composition and diversity will be stable longitudinally and seasonally and quite high, similar to that of large tropical rivers such as the Amazon, Mekong, Paraná, among others. 

PIs: Victor Saito (UFSCar), Dan Perkins (University of Roehampton) 

12/2020 - 11/2023

Food webs depict a road map of feeding interactions amongst organisms and provide a mechanistic way to understand how wildlife provides many ecosystem services that humans value. For example, the amount of nutrients, sunlight, and predators can influence algal blooms that impact the quality of drinking water. This project is motivated by the fact that we still lack a holistic understanding of the structure and functioning of food webs around the globe, and their response to environmental change (e.g. alterations in land use), given that temperate systems have been studied for a longer time in comparison to tropical counterparts. Addressing this knowledge gap offers the exciting opportunity to ask: are food webs from these two contrasting regions governed by general rules? We will address this question by combining our expertise to develop new analyses using existing datasets of freshwater species from temperate and tropical streams. 

PI: Ricardo Hideo Taniwaki (UFABC)

4/2021 - 4/2023

In Brazil, freshwater ecosystems are facing multiple anthropogenic pressures, such as agricultural intensification, urbanization and intensifying climate change effects. To disentangle these effects, multiple-stressor research seeks to analyze the variety of stressors acting simultaneously to elucidate how stressor interactions affect individual organisms to whole ecosystems. The aim of this project is to conduct the first mesocosm experiments investigating the interactive effects of climate change and agricultural stressors on freshwater organisms in Brazil. The experiments will disentangle the individual and combined effects of agricultural intensification and climate change on benthic stream macroinvertebrates as a model community. Understanding how climate and agricultural stressors individually and interactively impact aquatic organisms will inform stressor mitigation prioritization and best-practice agricultural management to protect freshwater ecosystems. 

PI: Tadeu Siqueira (UNESP) and Victor Saito (UFSCar)

11/2021 - 12/2022

Temporal variability in environmental conditions is used by organisms to adjust vital activities related to growth, reproduction and production of dormant, resistance stages. However, nature is also subject to unpredictable environmental change, which can generate equally unpredictable responses. In addition, most communities have complex dynamics generated by spatial flows. In this context and in a scenario of global changes and loss of biodiversity, investigating the interaction between unpredictable environmental change, spatial connectivity and production of dormant, resistance stages can broaden our understanding of how communities respond and persist to environmental changes taking place in the Anthropocene. Our main objectives here are (1) to investigate how the local and regional dynamics of metacommunities are affected by unpredictable environmental changes in different scenarios of spatial connectivity, and (2) to investigate whether the production and hatching of dormant, resistance stages interacts with dispersal, contributing to the spatio-temporal reorganization of metacommunities. In order to achieve these objectives, we will explicitly incorporate the role of dispersal and dormancy in an experimental manipulation of phyto- and zooplanktonic communities.  

PIs: Hugo Sarmento (UFSCar), Dan Perkins (University of Roehampton) and Victor Saito (UFSCar)

Fieldwork on 10/2019

This project represents a collaboration bringing together the complementary skills of three aquatic researchers working in distinct disciplines: Hugo Sarmento (FAPESP PI) microbial ecology; Dan Perkins (DP, prospective visitor) food web ecology and Victor Saito (FAPESP Co-I) community ecology. During the proposed 1-month exchange, we propose to further start matching an UK data os stream foodwebs with samplings in Brazil, enabling us to test macroecology hypotheses more rigorously. 

PI: Victor Saito

6/2019-12/2021

Biodiversity on Earth is constantly reorganizing itself in face of anthropic impacts, including aquatic biodiversity in face of agriculture expansion. This project aims to use aquatic mesocosms experiments, simulating lentic ecosystems and test different hypotheses regarding the reorganization of metacommunities inserted in agricultural matrices. In metacommunities the impacts of contaminants should be closely linked to the rate of dispersal between communities, as well as to the way agricultural contaminants work. In addition, in metacommunities embedded in agricultural landscape, not all local communities will be impacted. On the one hand, uncontaminated communities may be essential for the reorganization of impacted communities, since extinct species may be able to recolonize such sites. However, if the dispersion occurs from impacted to uncontaminated sites, indirect effects of contamination can be observed through the dispersal of organisms from sites with different conditions. Considering the fundamental role of zooplankton in the functioning of aquatic systems, our experiments have the potential to elucidate how this group will respond to the future pressures of agricultural expansion and how we can understand these responses through the lens of metacommunity dynamics. 

PI: Victor Saito

12/2018-2/2022

Water resources and freshwater biodiversity is being highly threatened by agriculture expansion, including sugar cane in Southeast Brazil. In this sense, we do not fully understand the possible impacts of agriculture contaminants on higher levels of ecological organization such as entire communities and on ecosystem processes, which maintain services for humanity. We aim to conduct mesocosm experimentation to obtain robust information on how important contaminants affect the aquatic biodiversity of communities and how this, in turn, could impact the functioning of the entire ecosystem.

PIs: Luiz Antonio Martinelli (ESALQ-USP), Janaina Braga do Carmo (UFSCar Sorocaba) and Luis Schiesari (EACH-USP)

2018 - 2022

Sugarcane ethanol is an alcohol-based renewable biofuel produced by the fermentation of sugarcane extract and molasses, and Brazil is the world’s largest producer of it. Nevertheless, our knowledge about the impacts of sugarcane ethanol produced in Brazil is still limited, especially for water and soils, and presents a serious obstacle in assessing sugarcane biofuel sustainability. Our ultimate goal is to provide a series of management practices that would preserve the environmental integrity, and maximize ecosystem services. More specifically we will address how land intensification affects the water, carbon, nitrogen and phosphorus dynamics, and how pollution (pesticides) and fragmentation from agriculture affect ecosystems functioning. 

PIs: Tadeu Siqueira, Jani Heino, Janne Soininen

2014 - 2018

The study of variation in biological communities - beta diversity - is fundamental for the understanding of biological homogenization. Despite increasing growth, patterns and processes related to beta diversity are still poorly considered in many ecosystems. Understanding of biological variation can not be achieved by ignoring the effects of anthropogenic disturbances. In this project, we will investigate the effects of landscape scale disturbances on the beta diversity of macroinvertebrates and diatoms of streams in Brazil and Finland through large surveys and modern statistical approaches. Our project should be fundamental to basic and applied ecology, with studies providing support for understanding the structuring of biological communities and the homogenization of biodiversity in the face of anthropic impacts.

PI: Gilmar Perbiche Neves

2017 - 2019

In this project we will study the viability of a zooplankton predator that feeds on Culicidae larvaes to control populations of Aedes mosquitos.

PI: Antonio Fernando Monteiro Camargo, Tadeu Siqueira

2013-2017

The Itanhaém river basin, south coast of São Paulo, has a great diversity of physiographic characteristics (vegetation, geological formations), land use and occupation (protected areas, agricultural areas and urban area) and water types (clear, black and brackish). The study of different communities in the rivers and streams of this basin allows the investigation of questions scientifically relevant both from the ecological theory point of view and from the point of view of watershed management. We expect to obtain robust and continuous time series on the variation of abiotic and biotic factors of the different rivers and streams, and to generate predictive models that will allow to follow the temporal changes that occur in the basin.