Project: NSFGEO-NERC: Why are complex habitats more diverse?

NSF Award Abstract:
Most habitats on the planet are surface habitats—from the abyssal trenches to the tops of mountains, from coral reefs to the tundra. Surface habitats vary in complexity, from relatively simple, planar surfaces to highly complex three-dimensional structures. One of ecology’s key paradigms is that complex habitats tend to contain more species and at higher abundances than flat, simple habitats. Meanwhile, human and natural disturbances are fast changing the complexity of habitats. Understanding and predicting the effects of these habitat changes on biodiversity is therefore now of paramount importance. The project uses novel 3D surface modelling technology to accurately measure habitat complexity and determine how changes in complexity affect the diversity of organisms that live among the habitat. The project trains two post-docs, one to two PhD students and up to 10 undergraduate and other interns on the use of cutting-edge technology to quantify ecological change. Outcomes from this project facilitate assessment and projection of impacts of ecosystem flattening on biodiversity and ecosystem function, as well as for forecasting the impact of change on ecosystems and economies.

The goal of this project is to quantify the geometry of surface habitats and examine habitat complexity-biodiversity coupling. Using coral reefs as a test system, the project integrates ecological theory, 3D surface mapping and associated biodiversity and environmental data, and experimental manipulations to build a mechanistic framework for complexity-biodiversity relationships. The project is generalizable to other surface habitats, and therefore can be used for testing complexity-biodiversity relationships globally and across other surface ecosystems. The project has three main objectives: (1) to develop an approach to quantify of habitat complexity by establishing the geometric variables that best capture surface complexity; (2) to integrate geometric and ecological theory to separate the effects of surface complexity and area on species’ richness, composition and abundances; and (3) to experimentally test theory predictions by measuring environmental and biodiversity changes caused by manipulations of habitat complexity. Success in this endeavor will provide a much-needed framework for predicting ecosystem responses to changing dimensionality of habitat structure.

This project is jointly funded by the Biological Oceanography Program and the Established Program to Stimulate Competitive Research (EPSCoR).

This is a project that is jointly funded by the National Science Foundation's Directorate of Geosciences (NSF/GEO) and the National Environment Research Council (NERC) of the United Kingdom (UK) via the NSF/GEO-NERC Lead Agency Agreement. 

NERC Award Abstract:
One of community ecology's few paradigms is that complex habitats tend to contain more species and at higher abundances than simple habitats. Currently, human and natural disturbances are changing the complexity of habitats faster than at any previous time in history. Understanding and predicting the effects of these changes on biodiversity is now of paramount importance. Yet, we have only a crude, correlative understanding of how complexity changes affect biodiversity, predicting that if habitat becomes flatter, species' diversity and abundances decline. Generating accurate predictions requires integration of the geometric and ecological principles that underpin complexity-biodiversity relationships. This project will build the tools to allow us to make process-based predictions about biodiversity change as a function of habitat complexity. It will do so by using mathematical theory, experimental manipulations, and ecological observations to build the mechanistic framework needed to make these predictions. We use a highly complex species rich system, coral reefs, as a case-study to implement and test predictions. This research will produce a general framework for testing complexity-biodiversity relationships globally and across ecosystems. INTELLECTUAL MERIT The major innovation of this research is integrating three disparate research areas-biophysics, 3D surface modelling technology, and ecological theory. This integration will for the first time allow us to quantify the interactions between biodiversity and 3D habitat structure. While the underlying components of this project are very effective on their own, they have until now developed independently of each other and the benefit of combining them to model complexity-biodiversity relationships has only recently been recognized. Despite intense interest in modelling the effects of environmental change, few present-day efforts to do so have a mechanistic basis, and almost all build in some way on the correlative responses of organisms to the environment, thus limiting their generality and predictive power. In contrast, our approach will develop basic theory that scales individual-level habitat associations to ecosystem-level common currencies using geometric principles, novel imaging technologies, ecological theory, rich historical data sets and experimental manipulation. Success in this endeavor will represent a major breakthrough in ecological research and understanding, and provide a much-needed framework for predicting ecosystem responses to changing dimensionality of habitat structure. BROADER IMPACTS This project will train 2 post-docs, 1-2 PhD student and up to 10 undergraduate and other interns on the use of cutting-edge technology to quantify ecological change. Our research will provide a tool for assessing and projecting the impact of ecosystem flattening on biodiversity and ecosystem function, as well as for forecasting the impact of change on our ecosystems and economy. We will maximize the impact of this tool by publishing code on GitHub and producing vignettes which make the theory developed accessible to a broader audience of scientists and practitioners. We will promote these tools online through websites and social media, and will run summer workshops to promote the uptake of this approach to explore scenarios of change and predict ecological consequences of different environmental management actions. The 3D maps generated in this project are particularly effective at communicating ecosystem change to a broad audience. We will create a web interface to visualize these changes and will promote them to schools and through HIMB's outreach program. Finally, we will engage more broadly in the dissemination of the results of our project through a science-art collaborative exhibition, which will explore changing shapes in the natural world.