Watershed determinants of terrestrial resource use by aquatic organisms across the world's freshwater hotspots
Lead Research Organisation:
University of Cambridge
Department Name: Plant Sciences
Abstract
North temperate regions hold much of the planet's freshwater, an essential ingredient for all life. But anthropogenic activities, such as land-use change, are dramatically altering these landscapes and threatening the delivery of key services provided by aquatic ecosystems, such as productive fish populations. Contemporary paradigms of aquatic conservation have emphasized inputs of pollutants and water resource development as causes of declining water security and biodiversity, but are failing when these two factors alone are improved. Increasingly, local watersheds are seen as critical controls of aquatic ecosystems. This is spurred by the recent discovery that pathways of energy mobilization upwards through aquatic food webs from microbes to fish rely on organic matter originating from terrestrial vegetation. In other words, new research is proving the adage that fish are in fact a "forest product".
Any factor that changes the quality and quantity of organic matter exported from land into water will influence the delivery of aquatic ecosystem services. For example, human land use practices and emerging disturbances, such as fire and forest pathogens, will change the cycling of nutrients from terrestrial vegetation into aquatic ecosystems. But which of these factors are most important and consistently operating across different geographic regions is unknown. Identifying these drivers is critical for developing new watershed-level approaches for conserving freshwater that link actions on land to processes in water.
Our research will test how different watershed characteristics control the use of terrestrial resources in aquatic food webs across lake-rich regions of the world. We will use our findings to forecast future changes in lake food webs associated with global change and recommend better practices for conserving freshwater resources. Our approach will be to bring together the leading international researchers studying terrestrial-aquatic linkages and synthesize available food web measurements from over 175 lakes. Using bioclimatic, vegetation, biogeochemistry, and land-use data extracted for each study lake, alongside cutting-edge statistical modelling techniques, we will predict the terrestrial drivers of lake food webs and link them to biomass accumulation by aquatic organisms.
Outcomes of this research will be highly relevant to the UK and international policy around managing freshwater supplies by demonstrating strong linkages between terrestrial and aquatic ecosystems. A particular focus of our research is improving the Water Framework Directive (WFD), a piece of pan-European legislation designed to protect freshwater. We hope to use our research to impact policy associated with the WFD by engaging with the European Commission in a knowledge exchange symposium that we are organizing at the conclusion of our project. This project will also have many applications for improving regional land use planning and management, as well as restoring environmentally damaged landscapes. We are working closely with partners in the mining industry and government in associated NERC-funded projects and will use the results of this project to better inform these partners of the best practices for re-vegetating degraded watersheds.
Any factor that changes the quality and quantity of organic matter exported from land into water will influence the delivery of aquatic ecosystem services. For example, human land use practices and emerging disturbances, such as fire and forest pathogens, will change the cycling of nutrients from terrestrial vegetation into aquatic ecosystems. But which of these factors are most important and consistently operating across different geographic regions is unknown. Identifying these drivers is critical for developing new watershed-level approaches for conserving freshwater that link actions on land to processes in water.
Our research will test how different watershed characteristics control the use of terrestrial resources in aquatic food webs across lake-rich regions of the world. We will use our findings to forecast future changes in lake food webs associated with global change and recommend better practices for conserving freshwater resources. Our approach will be to bring together the leading international researchers studying terrestrial-aquatic linkages and synthesize available food web measurements from over 175 lakes. Using bioclimatic, vegetation, biogeochemistry, and land-use data extracted for each study lake, alongside cutting-edge statistical modelling techniques, we will predict the terrestrial drivers of lake food webs and link them to biomass accumulation by aquatic organisms.
Outcomes of this research will be highly relevant to the UK and international policy around managing freshwater supplies by demonstrating strong linkages between terrestrial and aquatic ecosystems. A particular focus of our research is improving the Water Framework Directive (WFD), a piece of pan-European legislation designed to protect freshwater. We hope to use our research to impact policy associated with the WFD by engaging with the European Commission in a knowledge exchange symposium that we are organizing at the conclusion of our project. This project will also have many applications for improving regional land use planning and management, as well as restoring environmentally damaged landscapes. We are working closely with partners in the mining industry and government in associated NERC-funded projects and will use the results of this project to better inform these partners of the best practices for re-vegetating degraded watersheds.
Planned Impact
This project will test how watershed characteristics control the use of terrestrial resources in aquatic food webs across the world's lake hotspots. In addition to benefiting academic communities by advancing important scientific questions, such as those around the levels of terrestrial support of aquatic consumers, and generating data that will be available to other researchers, our work has timely relevance to the formulation of policy associated with freshwater management in the EU and internationally. As seen in the Letter of Support from the European Commission, our project has been carefully designed from inception to set objectives that address the needs of end-users that must manage and restore water bodies.
Defra has recently (9 Apr 2013) adopted a policy to improve the quality of water-bodies, as only 27% of those in England are classified as being of "good status" under EU standards. However, most of their actions are focused on reducing agricultural, urban, and chemical pollution. A recent article published in the journal Nature (30 Sep 2010) has shown that controlling pollution alone cannot entirely improve the functioning of freshwater ecosystems. Rather, the quantity and quality of organic matter exported from soils may control the downstream benefits within receiving waters. The potential to predict how terrestrial and aquatic ecosystems interact remains a key need for many end-user communities. Through close collaboration in this and other current NERC-funded research, we will benefit government and industry by generating guidelines to improve environmental sustainability and protection. We will also inform watershed management at an international level with our cross-continental data synthesis and address the following issues of high priority for NERC: sustainable use of natural resources; biodiversity; and environment, pollution and human health.
Other users in government, industry, and the public that may wish to hear the outcomes of our project will be engaged through a symposium organized at a major scientific meeting and workshops held in North America and Europe associated with our other funded research. The key attendee at the symposium associated with this project will be the European Commission Directorate-General for the Environment, who have been tasked with aiding the implementation and reporting on the Water Framework Directive (WFD). The WFD mandates EU member countries to protect and restore freshwater ecosystems, but it conspicuously lacks an explicit focus upon how land itself influences water. As the First Management Cycle of the WFD ends in 2015, there is the potential for our project to inform decision makers from many different nations of the need for much broader watershed-level perspectives when enacting local, regional, national, and international laws for protecting freshwater ecosystems. We will feed the results of this project directly to the European Commission to help guide these outcomes. Additionally, interested users in the UK will include Natural England, Defra/Cefas, the Forestry Commission, JNCC, local councils, and local naturalist groups, as well as resource industries. They will benefit from increases in the effectiveness of environmental policy and sustainability.
Finally, we expect that the general public will be interested in the outcomes of our project and benefit from an increased awareness and understanding of science. We will engage with them through traditional media facilitated by the Cambridge University Media Relations team and new social media tools, such as blogs and Twitter.
Defra has recently (9 Apr 2013) adopted a policy to improve the quality of water-bodies, as only 27% of those in England are classified as being of "good status" under EU standards. However, most of their actions are focused on reducing agricultural, urban, and chemical pollution. A recent article published in the journal Nature (30 Sep 2010) has shown that controlling pollution alone cannot entirely improve the functioning of freshwater ecosystems. Rather, the quantity and quality of organic matter exported from soils may control the downstream benefits within receiving waters. The potential to predict how terrestrial and aquatic ecosystems interact remains a key need for many end-user communities. Through close collaboration in this and other current NERC-funded research, we will benefit government and industry by generating guidelines to improve environmental sustainability and protection. We will also inform watershed management at an international level with our cross-continental data synthesis and address the following issues of high priority for NERC: sustainable use of natural resources; biodiversity; and environment, pollution and human health.
Other users in government, industry, and the public that may wish to hear the outcomes of our project will be engaged through a symposium organized at a major scientific meeting and workshops held in North America and Europe associated with our other funded research. The key attendee at the symposium associated with this project will be the European Commission Directorate-General for the Environment, who have been tasked with aiding the implementation and reporting on the Water Framework Directive (WFD). The WFD mandates EU member countries to protect and restore freshwater ecosystems, but it conspicuously lacks an explicit focus upon how land itself influences water. As the First Management Cycle of the WFD ends in 2015, there is the potential for our project to inform decision makers from many different nations of the need for much broader watershed-level perspectives when enacting local, regional, national, and international laws for protecting freshwater ecosystems. We will feed the results of this project directly to the European Commission to help guide these outcomes. Additionally, interested users in the UK will include Natural England, Defra/Cefas, the Forestry Commission, JNCC, local councils, and local naturalist groups, as well as resource industries. They will benefit from increases in the effectiveness of environmental policy and sustainability.
Finally, we expect that the general public will be interested in the outcomes of our project and benefit from an increased awareness and understanding of science. We will engage with them through traditional media facilitated by the Cambridge University Media Relations team and new social media tools, such as blogs and Twitter.
Organisations
- University of Cambridge, United Kingdom (Lead Research Organisation)
- McGill University, Canada (Collaboration, Project Partner)
- Institute of Biology (IBENS) (Collaboration)
- Umea University, Sweden (Collaboration, Project Partner)
- University of Notre Dame (Collaboration)
- Lund University (Collaboration)
- University of Virginia, United States (Collaboration, Project Partner)
- University of Notre Dame Indiana, United States (Project Partner)
Publications

Tanentzap A
(2017)
Terrestrial support of lake food webs: Synthesis reveals controls over cross-ecosystem resource use
in Science Advances

Tanentzap AJ
(2015)
Resolving Conflicts between Agriculture and the Natural Environment.
in PLoS biology
Description | We have discovered that the small aquatic invertebrates known as zooplankton, which dominate lake food webs and are important for feeding fish, are comprised of at least 42% terrestrial-derived material across northern hemisphere lakes. This level of support increases in lakes with large physical and hydrological connections to catchments that are rich in above- and below-ground organic matter. Conceptually, we have also provided the first global test for theory predicting when cross-ecosystem resources will be most utilised. We generally found that spatial resource fluxes were more utilised in ecosystems that were unproductive and well connected to donor habitats. Finally, our work has helped resolve intense debate over the extent to which aquatic food webs are supported by terrestrial-derived material. Overall, our results point to how important functions in freshwater ecosystems that are regulated by zooplankton, such as fish production and carbon sequestration, can have unintended and surprising responses to human activities on land. |
Exploitation Route | Academic routes: Our results show how researchers measuring the productivity of aquatic organisms must consider the vegetation and land use of surrounding watersheds, and hopefully inspire those studying lakes and rivers to think "outside the water". The data associated with our project will also deliver benefits to future meta-analyses and aid social scientists valuing the importance of terrestrial ecosystems. Non-academic routes: Our findings might be used by government agencies responsible for informing and formulating policy on water resources, watershed protection, and land use practices. Non-governmental organisations focused on biodiversity conservation and local wildlife and fishing clubs might also be interested to use our results in planning conservation interventions. |
Sectors | Agriculture, Food and Drink,Environment,Leisure Activities, including Sports, Recreation and Tourism,Government, Democracy and Justice,Other |
Title | IOF database |
Description | Database of consumer isotope measurements in temperate lakes along with associated lake water chemistry and geospatial catchment variables. |
Type Of Material | Database/Collection of data |
Year Produced | 2014 |
Provided To Others? | Yes |
Impact | In progress. |
Description | IOF |
Organisation | Institute of Biology (IBENS) |
Department | Department of Biology |
Country | France |
Sector | Academic/University |
PI Contribution | Intellectual input and expertise in data synthesis/ |
Collaborator Contribution | Intellectual input, access to data, equipment and facilities. |
Impact | Organised symposium at Joint 2014 Annual Meeting British Ecological Society and Société Française d'Ecologie. Other outputs in preparation. |
Start Year | 2014 |
Description | IOF |
Organisation | Lund University |
Department | Department of Physical Geography and Ecosystem Science |
Country | Sweden |
Sector | Academic/University |
PI Contribution | Intellectual input and expertise in data synthesis/ |
Collaborator Contribution | Intellectual input, access to data, equipment and facilities. |
Impact | Organised symposium at Joint 2014 Annual Meeting British Ecological Society and Société Française d'Ecologie. Other outputs in preparation. |
Start Year | 2014 |
Description | IOF |
Organisation | McGill University |
Country | Canada |
Sector | Academic/University |
PI Contribution | Intellectual input and expertise in data synthesis/ |
Collaborator Contribution | Intellectual input, access to data, equipment and facilities. |
Impact | Organised symposium at Joint 2014 Annual Meeting British Ecological Society and Société Française d'Ecologie. Other outputs in preparation. |
Start Year | 2014 |
Description | IOF |
Organisation | Umea University |
Country | Sweden |
Sector | Academic/University |
PI Contribution | Intellectual input and expertise in data synthesis/ |
Collaborator Contribution | Intellectual input, access to data, equipment and facilities. |
Impact | Organised symposium at Joint 2014 Annual Meeting British Ecological Society and Société Française d'Ecologie. Other outputs in preparation. |
Start Year | 2014 |
Description | IOF |
Organisation | University of Notre Dame |
Department | Department of Biological Sciences |
Country | United States |
Sector | Academic/University |
PI Contribution | Intellectual input and expertise in data synthesis/ |
Collaborator Contribution | Intellectual input, access to data, equipment and facilities. |
Impact | Organised symposium at Joint 2014 Annual Meeting British Ecological Society and Société Française d'Ecologie. Other outputs in preparation. |
Start Year | 2014 |
Description | IOF |
Organisation | University of Virginia (UVa) |
Department | Department of Environmental Sciences |
Country | United States |
Sector | Academic/University |
PI Contribution | Intellectual input and expertise in data synthesis/ |
Collaborator Contribution | Intellectual input, access to data, equipment and facilities. |
Impact | Organised symposium at Joint 2014 Annual Meeting British Ecological Society and Société Française d'Ecologie. Other outputs in preparation. |
Start Year | 2014 |
Description | BES 2014 talk (Tanentzap) |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Other audiences |
Results and Impact | Presented preliminary research from the grant that helped to improve later research. |
Year(s) Of Engagement Activity | 2014 |
URL | http://www.britishecologicalsociety.org/wp-content/uploads/BES-SFE-Online-Programme.pdf |
Description | BES symposium 2014 |
Form Of Engagement Activity | Participation in an activity, workshop or similar |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Other audiences |
Results and Impact | Organised symposium on Extending Freshwater Management beyond Shorelines by Linking Aquatic and Terrestrial Ecosystems. Included six invited talks and panel discussion. |
Year(s) Of Engagement Activity | 2014 |
URL | http://www.britishecologicalsociety.org/wp-content/uploads/BES-SFE-Online-Programme.pdf |
Description | Cambridge TV subsidies |
Form Of Engagement Activity | A broadcast e.g. TV/radio/film/podcast (other than news/press) |
Part Of Official Scheme? | No |
Geographic Reach | Regional |
Primary Audience | Media (as a channel to the public) |
Results and Impact | Featured story on Cambridge TV with interview. |
Year(s) Of Engagement Activity | 2015 |
URL | http://www.cambridge-tv.co.uk/farmers-subsidy/ |
Description | Yahoo farming |
Form Of Engagement Activity | A magazine, newsletter or online publication |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Media (as a channel to the public) |
Results and Impact | Featured article on Yahoo News. |
Year(s) Of Engagement Activity | 2015 |
URL | https://www.yahoo.com/news/20-billion-handout-thats-destroying-environment-165324319.html |