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The State of Nature in the EU: an unfavourable picture for freshwaters

May 26, 2015
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Avon Meadows Community Wetlands in Worcestershire, England have been created on the rural-urban fringe to encourage biodiversity, reduce flooding and improve water quality on the nearby River Avon. Image: Geoff Moore | Flickr | Creative Commons

Last week the European Environment Agency released their ‘State of Nature in the EU‘ report, which uses comprehensive data collected across the continent between 2008-2012 assess the status of and trends in biodiversity and natural habitats across Europe.  Data on Europe’s species and habitats was collected by individual countries (or member states) as part of monitoring for the Birds Directive and the Habitat Directive – European environmental policies designed to help guide conservation, protected area management and environmental restoration across the continent (more information on these at the bottom of the post).

Hans Bruyninckx, the Executive Director of the European Environment Agency said, “This unique assessment is a first of its kind, building on extensive observation networks of experts and citizens alike. Despite some information gaps, it provides the most complete picture of Europe’s biodiversity to date.  The results are mixed but clear. When implemented well, conservation measures work and improve the status of habitats and species on the ground. Such improvements remain limited and patchy, and unfortunately Europe’s biodiversity is still being eroded overall and the pressures continue”

The results of the study for freshwaters are largely unfavourable.  Around half of the conservation status of river and lake habitats and species reported to the Habitats Directive are deemed ‘unfavourable-inadequate‘.  It is worth noting that the habitats and species assessed by the Habitats Directive were already deemed rare, endangered or otherwise threatened.  However, the picture is still not positive: around a third of these conservation statuses are in decline, suggesting that a significant proportion of Europe’s freshwater species and habitats face significant threats to their health and diversity.

Rivers and lakes were found to be most impacted by modifications to natural conditions (for example: river channel modification and fragmentation, water abstraction, draining of wetlands), water pollution and the impact of agriculture (e.g. fertiliser run-off).  Changes to natural conditions were particularly damaging pressures for birds which live in freshwater habitats, presumably due to a reduction in available nesting and feeding sites.

Protected area designation was reported as the most popular conservation measure implemented by member states to mitigate the identified threats for both birds and wider habitats.  For non-bird species – largely fish, invertebrates and amphibians – conservation measures were more diverse, including restoring hydrological regimes, legally protecting habitats and species, and improving water quality.

MARS project leader Daniel Hering commented on the findings, suggesting that whilst water quality in Europe is improving, any widespread improvements in freshwater biodiversity and habitat quality lag well behind:

“The negative assessment of river and lake conservation status is in line with the results of the Water Framework Directive monitoring. Both the assessment under the Habitats Directive and under the Water Framework Directive rate the status of lakes and rivers quite negatively.

The results are consistent but also quite surprising for many people who acknowledge the great improvement of water quality in recent decades. Strong pollution has vanished from European rivers and lakes – but biodiversity and ecosystem functions are still impoverished.

Freshwater ecosystems in most parts of Europe are still stressed, but the stressors are less visible than in former times. Eutrophication, pesticides, removal of riparian vegetation, water abstraction – all these stressors affect a large proportion of Europe’s waters. In former times the wastewater from households and industries were the main threat; nowadays, it is the way we practise agriculture.”

Read the State of Nature in the EU Report online

The Birds Directive and the Habitats Directive

The Birds Directive was set up in 1979, and aims to protect all wild birds with natural ranges inside Europe, and identifies 193 species which are in need of special conservation measures due variously to rarity, threat of extinction or loss of habitat.  The Birds Directive also requires European member states to designate Special Protection Areas for the conservation of endangered bird species.

The Habitats Directive was set up in 1992 with the aim of ensuring the conservation of rare, threatened or endemic species of plants and animals across Europe.  The Directive covers over 1,250 species and 233 habitat types across the continent, and requires member states to designate and manage Special Areas of Conservation and implement other management measures to restrict the taking, capturing or killing of important plant and animal species.

A new freshwater fish database for Spain

May 20, 2015

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The Iberian Society of Ichthyology has recently launched the Freshwater Fish Database for Spain.  Despite the large number of research and technical studies done on freshwater fishes on the Iberian Peninsula, the resulting data is highly dispersed and not available for public use, or for environmental management or research (a common problem for such data, as we wrote about for the Freshwater Information Platform launch recently)

In response to this difficulty in accessing data, the Society worked to compile information on Iberian freshwater fishes found in research centres, public administrations, and available on the internet in technical reports and scientific publications, among others. This ongoing work has created a database for general public use, a database for the use of environmental managers and an interactive web platform to facilitate access to this information.

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The databases integrate information about fish species abundance, habitats, historical evolution, population trends, major threats, conservation actions, human impact (pollution, water extraction among others) and fishing intensity.

Accurate information on species distribution is important in helping environmental managers develop monitoring plans and conservation strategies. Similarly, the historical information on species distribution will help in the scientific analysis of freshwater fish populations.

Read more on the database here

Contact project co-ordinator Filipe Ribero: cartapiscicola@sibic.org

This project was funded by the Fundacion da Biodiversidad, University of Navarra, Veso and SIBIC own funds.

Multiple stresses on freshwaters in the Upper Jordan Valley: new MARS research and collaboration

May 12, 2015
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Dr. Armin Lorenz from the Aquatic Ecology group at the University of Duisburg-Essen demonstrates the multi-habitat sampling methodology. Image: Christian Feld

A group of researchers from the Aquatic Ecology group at the University of Duisburg-Essen, including MARS scientists Christian Feld and Daniel Hering, recently visited the Upper Jordan Valley in Israel as part of a trip funded by the German-Israeli Foundation for Scientific Research and Development to begin work on assessing the multiple stresses that impact the region’s freshwaters.

The visit aimed to kick-off a new research project in collaboration with Dr. Gideon Gal and his group at the Kinneret Limnological Laboratory in Migdal, Israel. Together with Yaron Hershkovitz, an Israeli guest scientist at the University of Duisburg-Essen, the team started to identify suitable sites for fieldwork to study the pressures acting on the upper reaches of the River Jordan, before it meets Lake Kinneret (otherwise known as the Sea of Galilea).  The fieldwork, which will run until June, focus on the health and diversity of aquatic invertebrates such as insects and molluscs as indicator species for the wider health of the freshwater ecosystem in response to stresses like pollution and drought (see an earlier blog on indicator species in Israel).

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An intermittent stream, already dry during the field trip in March. Image: Christian Feld

One major challenge for the team was to identify streams in the Jordan catchment that would not dry up completely in the hot early summer months, and so contain enough water to allow their ecological sampling to go ahead (we’ve written before about intermittent and temporary rivers here).  Once identified, these streams were split in a typology similar to that used in the Water Framework Directive by their geology (largely limestone and basalt) and size.

MARS researcher Christian Feld explains more about the fieldwork and its outcomes:

“The sampling campaign in May aims to collect macroinvertebrate communities from nearly 50 different streams. For the first time, we will apply a standardised monitoring scheme in order to ensure the comparability of the results. This procedure is alike those developed to implement the Water Framework Directive in Europe. This will open the opportunity for us to consult monitoring results from other Mediterranean countries that are Member States of the European Union.

This also offers the opportunity for MARS to collaborate with the German-Israeli Foundation project, as the monitoring data analysed in both projects are similar. Thus, the GIF project directly contributes a 17th case study to the existing 16 case studies of the MARS project. On the other hand, the GIF project can benefit from the modelling methodology developed in MARS to identify and predict the effects of multiple stressors on freshwater ecology.”

We will continue to follow the progress of the team’s research and collaborations in Israel and update you with their results.

A selection of Christian’s fascinating photographs from the fieldtrip are below.

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A potential study stream in the Upper Jordan Valley. Image: Christian Feld

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Nir Koren from the Lake Kinneret Laboratory takes a multi-habitat sample. Image: Christian Feld

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Dr. Yaron Hershkovitz from Tel-Aviv University coordinates and conducts the field work in the project. Image: Christian Feld

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Freshwater resources that are vital to the Jordan Valley and its human and non-human inhabitants are under increasing pressures. Image: Christian Feld

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Site selection always starts with thoughtful map-work… Image: Christian Feld

A symposium was held at Kinneret Limnological Laboratory (KLL), to inform a wider group of scientists, and environmental and water managers about the project. Image: Christian Feld

A symposium was held at Kinneret Limnological Laboratory (KLL), to inform a wider group of scientists, and environmental and water managers about the project. Image: Christian Feld

Project funding:

The GIF project (“Ecological status and ecosystem services of the Lake Kinneret catchment: setting the scene for the management of a multi-stressed region.”) is funded by the German-Israeli Foundation for Scientific Research and Development, contract No. G-1272-203.13/2014.

The MARS project (Managing Aquatic ecosystems and water resources under multiple stress) is funded by the European Union under the 7th Framework Programme, contract no. 603378.

The Freshwater Information Platform is launched

May 6, 2015

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Human-driven environmental pressures such as water pollution, intense land-use and climate change are increasingly threatening the health and diversity of European freshwater ecosystems. Over recent years, many European Union funded research projects have investigated the causes of these pressures and their effects on rivers, lakes and wetlands, and developed appropriate conservation and rehabilitation strategies. However, the scientific data generated by these projects is often difficult for water managers, policy makers, scientific communities and the general public to access from a huge number of scientific papers and research project websites.

In order to make this detailed and wide-ranging knowledge of freshwater ecosystems accessible to all, four European research institutes in Austria, Belgium and Germany have joined forces to launch the Freshwater Information Platform, an interactive website integrating results and original data stemming from finished, ongoing, and future freshwater research projects.

MARS scientist Astrid Schmidt-Kloiber from BOKU in Vienna outlined the potential of the Freshwater Information Platform as a valuable tool for conservation, stating that, “Freshwater environments are subject to numerous damaging pressures leading to a significant threat to their biodiversity. The Freshwater Information Platform helps freshwater scientists to overcome the challenging task to find scattered research resources, by pooling relevant information in one single place. This will help improve the understanding of freshwaters and provide a stronger voice for their conservation.”

The Freshwater Information Platform offers a forum for information exchange and open-access publishing of maps and data, and aims to stimulate cutting-edge research and collaborations in the field. The Platform provides a unique and comprehensive knowledge base for sustainable and evidence-based management of our threatened freshwater ecosystems and the resources they provide.

For Daniel Hering, leader of the MARS project at UDE in Germany, high-quality data is key: “The efficiency of freshwater ecosystem protection and restoration is largely driven by the quality of scientific data that it relies on. The identification of sensitive areas and species, the development of restoration measures and the prediction of climate change effects: all are complex scientific tasks requiring high-quality data. The Freshwater Information Platform is an extremely valuable resource in providing the evidence needed to guide successful and sustainable freshwater management and policy.”

Aaike De Wever from RBINS in Belgium echoes this sentiment, encouraging freshwater scientists to get involved, to share their data and to potentially spark new collaborations: “Through the Freshwater Biodiversity Data Portal – integrated in the Freshwater Information Platform – we encourage scientists to publish their data on species observations online. By bringing together a large number of freshwater datasets we want to support large-scale environmental analyses and modelling, which improves our understanding and capacity to manage freshwater environments.”

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The Platform contains several complementary sections, either providing access to original data or summarising research results in an easily digestible way. All sections are composed as ‘living documents’ that will be continuously improved and updated.

The Freshwater Biodiversity Data Portal provides access to data on the distribution of freshwater organisms (such as fishes, insects and algae), both in Europe and worldwide, whilst the Global Freshwater Biodiversity Atlas provides a series of maps on freshwater biodiversity richness, threats to freshwaters (or ‘stressors’) and the effects of global change on freshwater ecosystems.

The Freshwater Species Traits Database integrates the knowledge on the ecology of around 20,000 species inhabiting European freshwater ecosystems, including information about where species live, what they feed on or how tolerant they are to pollution.

The Freshwater Metadata section provides an overview of hundreds of major data sources related to freshwater research and management and offers the option to publish such data in the Freshwater Metadata Journal. The Freshwater Information Platform also provides a collection of research tools, information about freshwater-related policies and relevant European and global networks relating to freshwater science and policy.  In short, it provides an invaluable tool for anyone wanting to do freshwater research, conservation or policy.

Finally, this blog – publishing features, research highlights, interviews and podcasts on freshwater science, policy and conservation – is the final piece in the FIP jigsaw, helping communicate a variety of important research.

The last word on the Freshwater Information Platform comes from former BioFresh leader Klement Tockner at IGB in Germany: We are fundamentally and in most cases irreversibly altering how the natural world functions. The consequences for the natural systems on which we depend are such that they may threaten our own survival. The Freshwater Information Platform provides a shared research infrastructure of global relevance that facilitates tracing the multifaceted consequences of accelerating environmental change for freshwater resources and biodiversity.”

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You can access and explore the Freshwater Information Platform here.

Contributing institutions:

University of Natural Resources and Life Sciences (Vienna, Austria), BOKU
University of Duisburg-Essen, Aquatic Ecology (Germany), UDE
Leibniz-Institute of Freshwater Ecology and Inland Fisheries (Berlin, Germany), IGB
Royal Belgian Institute of Natural Sciences (Brussels, Belgium), RBINS

‘Water Lives…’ at the UK Green Film Festival

April 27, 2015

‘Water Lives…’, the freshwater science communication animation produced for the EU BioFresh project in 2012 has been selected for this year’s UK Green Film Festival and will be screened before the feature film H2OMX at cinemas across the UK between 3-10th May.  Details of screenings can be found here.

‘Water Lives…’ was designed to draw attention to the important (yet largely invisible) life that underpins and sustains our freshwater ecosystems.  The project brought artists and EU scientists together to collaborate and communicate the concept that freshwater is more than an inert resource: instead a living, dynamic system inhabited by beautiful, important organisms largely unseen by the naked eye. It was animated by Adam Proctor, with a soundtrack by Tommy Perman and haiku by John Barlow.

‘Water Lives…’ was produced by Rob St. John and Paul Jepson at the School of Geography and the Environment, University of Oxford as part of an interdisciplinary art-science project in collaboration with BioFresh scientists Rick Battarbee from University College London and Ana Filipa Filipe from the University of Barcelona alongside Alistair Seddon from the University of Oxford Zoology department.

More information on the University of Oxford School of Geography and the Environment website

Health Care 2030: Predicting trends in future chemical pollution at the first SOLUTIONS workshop

April 20, 2015
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Group picture of the participants at the SOLUTIONS Workshop “Health Care 2030”. Image: David López Herráez.

By Dirk Bunke, Werner Brack and David López Herráez.

How does the availability and use of water resources, population demography, agriculture, healthcare, climate and so on affect the patterns of global chemical pollution?  And is it possible – at least to a certain degree – to predict future emerging pollutants?

The EU SOLUTIONS project aims to address these questions by modelling future scenarios for freshwater chemical pollution, to help develop assessment tools and abatement options for emerging pollution challenges. The project’s first task was to identify and examine patterns and trends in current chemical pollution. Following this initial analysis, SOLUTIONS scientists are working with external experts in dedicated workshops to discuss economic, technological and demographic trends in society, in order to identify links with new and emerging pollutants.

intro.pollutionThe first SOLUTIONS workshop: Health Care 2030

SOLUTIONS held the first of four workshops on the topic in Frankfurt a.M. on 23rd and 24th February 2015. The first workshop – entitled “Health Care 2030” and organized by Dirk Bunke from the Öko-Institut (Institute for Applied Ecology), Germany – focused on chemical substances related to human health care.

Following the presentation of model on future climate change and its consequences for future health care by Michael Depledge from the University of Exeter, the “Health Care 2030” workshop discussed potential changes in human disease patterns and pharmaceutical use considering projections by the Intergovernmental Panel on Climate Change (IPCC). At present, climate change is one of the most intensely discussed factors to potentially affect our future environments. Climate-related environmental alterations are expected to be associated with an increase in chronic diseases already common in the Northern Hemisphere – such as cardiovascular, respiratory and mental illnesses – potentially leading to a greater need for chemical medications, such as vasodilators, anticoagulants, anti-inflammatories, antidepressants and analgesics, which then will potentially be circulated into the environment.

Changes in climate are also expected to prompt an increase in pathogens and invertebrate vectors (such as mosquitos) for disease. As new disease threats emerge, higher pharmaceutical use seems inevitable, and is likely to include medical drugs not commonly employed at present, such as antiprotozoals for malaria, amoebiasis and others. Further factors expected to affect future pharmaceutical consumption are global societal health trends (increased prevalence of obesity, diabetes, cancer and depression), increased production and access to drugs (e.g. in newly industrialized countries), novel chemical treatments, biodiversity loss and emerging diseases.

In terms of predicting future freshwater chemical pollution, such developments need to be viewed in the context of other environmental changes, such as fluctuations in river flows as a result of droughts, floods and storms, which can disturb historical ‘legacy’ pollutants from sediments.  Similarly, an increase in surface water temperature can also alter the environmental fate of emitted chemicals, influencing their mobility and bio-accumulation.

Workshop presentations and discussions: chemical pollution from healthcare and agriculture

Following presentations at “Health Care 2030” workshop given by Christian Brandt (University Clinical Center Frankfurt) and Engelbert Schramm (ISOE, Institute for Social-Ecological Research, Frankfurt), workshop participants discussed the current and future role of health care systems – especially hospitals – as sources of environmental pollution. In general, health care personnel are educated about how to correctly dispose of waste in hospitals with largely well-structured waste management plans, thus reducing the risk of contamination of other patients and the environment. Nevertheless, infectious microorganism agents from gut flora and multi-drug resistant bacteria do represent a serious threat to the environment, and this may become more serious in the future if current trends in the use of antibiotics continue.

This threat posed by chemical pollution is enhanced by industrial livestock farming involving high and potentially improper antibiotic use.  Drug emissions from hospitals are of local relevance but are easily exceeded by diffuse emissions from households, thereby posing spatial challenges for pollution management. Another key issue is the increasing requirement for cleaning and disinfection to safeguard hospital hygiene, for example in the cleaning of surfaces and surgical instruments. In this respect, and taking into account global population growth, the emissions of chemicals from household cleaning products are also expected to increase in coming decades.

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Annual prescribing rates by therapeutic group in males from England and Wales in the year 1998. Image: Royal Commission on Environmental Pollution report on “Demographic Change and the Environment” February 2011; Information used under UK Open Government Licence v3.0.

Identifying and managing the causes of future chemical emissions: Health Care 2030

As a result of discussions at the SOLUTIONS workshop, the key drivers of future “Health Care 2030” chemical emissions were identified as: i) an increase in pharmaceutical production and consumption; ii) environmental politics (i.e. how pollution is managed by policy); iii) demographic change; and iv) developments in human health systems and veterinary practices. Participants at the workshop discussed possible “options to act”, suggesting palliative measures to manage the impact of drugs released into the environment.

Hans-Christian Schäfer (Deutsche Bundesstifung Umwelt) reported on several technological approaches to minimize drug emissions. This involves the advancement of effluent treatments (e.g. the removal of micro-pollutants via sludge or charcoal absorption, membrane filtration, and the advanced oxidation or UV-photolysis of molecules). Similarly, Schäfer outlined societal incentives to encourage the pharmaceutical industry to achieve a business model combining entrepreneurial interests, higher efficiency of pharmaceuticals and a sustainable “benign by design” model of drug production.

Taking into account the uncertainties associated with future developments in chemical use and emissions from the pharmaceutical industry, the best option for action may be optimisation in small steps along the whole supply chain: from the design and production of a certain pharmaceutical, to its legal authorization and environmental regulation, and finally its consumption and use. Education may help to avoid bad practices in drug use such as the disposal of pills and tablets via toilets or sinks.

Klaus Kümmerer (University Leuphana Lüneburg) presented innovative strategies for sustainable drug design, including practical examples of the “benign by design” approach. Such drug-design safeguards against environmental degradation by avoiding persistent and toxic transformation products. Further important tasks in the future will include the promotion of behavioral changes such as: increasing public exercise; reducing exposure to hazardous substances and pathogens; and raising awareness on the correct use and dosage of pharmaceuticals, for example this environmental product labelling in Sweden.

intro.qualitySumming up and looking forward: Food 2030

The intense and productive exchanges which took place at the workshop created new insights in future developments of “Health Care 2030”. For all workshop participants it was worthwhile to look beyond a single own research field, in order to gain an interdisciplinary approach to chemical pollution management. Within the SOLUTIONS project, the results of the workshop will be used to develop a better understanding of future chemical pollution trends and patterns, to predict the consequences of chemical risks to the aquatic environment, to propose specific substances and substance groups for environmental modeling and monitoring, and finally to develop management options for future emerging pollutants.

The next workshop of the series will focus on “Food 2030: Trends in production and consumption”. The workshop will address a broad range of topics from antibiotics in animal farming and trends in agricultural use of pesticides to the impacts of convenience food. Once again the key question is how these trends influence the quality of our freshwaters – a key challenge for both science and society.

Attendees:

Attendees from following institutions participated in the first workshop of the series:

Dirk Bunke, Susanne Moritz and Lea Strigl from Öko-Institut (Institute for Applied Ecology – Germany); Werner Brack and David López Herráez from the Helmholtz Center for Environmental Research – UFZ; Michael Depledge from University of Exeter Medical School; Klaus Kümmerer from the Leuphana University Lüneburg; Christian Brandt from University Clinical Center Frankfurt; John Munthe and Eva Brorström-Lundén from the Swedish Environmental Research Institute – IVL; Guy Engelen and Frank Sleeuwaert from the Flemish Institute for Technological Research – VITO; Hans-Christian Schäfer from Deutsche Bundesstiftung Umwelt – DBU; Engelbert Schramm from the Institute for Social-Ecological Research Frankfurt; Jaroslav Slobodnik from Environmental Institute – Slovakia; Thomas ter Laak from Watercycle Research Institute – The Netherlands; and Lonneke van Leeuwen from the Dutch National Institute of Public Health and the Environment – RIVM.

Nutrient pollution can harm stream ecosystems in previous unknown ways

April 17, 2015
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A North Carolina forest stream. Image: Jenn Deane | Flickr Creative Commons

It has long been known that nutrient pollution – the overloading of chemicals such as nitrogen and phosphates from sources such as agricultural fertilisers – can have potentially harmful effects on freshwater ecosystems.  In particular, eutrophication – the rapid growth of algal ‘blooms’ – can starve the aquatic environment of light and dissolved oxygen, prompting shifts in the form and function of the ecosystem, and potentially causing collapses in populations of other freshwater plants and animals.

However, a new study published in the journal Science by a team of researchers from the University of Georgia, USA suggests that nutrient pollution can also prompt significant losses of carbon from forest stream ecosystems, which in turn reduces their ability to support aquatic life.

The study, by Amy D. Rosemond and colleagues, shows that when nutrient levels are moderately increased in the stream, the residence time  (i.e. the amount of time it remains in the stream) of organic carbon molecules mineralised from leaf litter and woody debris drops by around a half.  This is because increased nutrient levels stimulate microbes to break down leaves and woody debris at a quicker rate, causing carbon to be lost to the atmosphere as carbon dioxide.

Whilst nitrogen and phosphorous are important in catalysing this process of microbial decomposition, when their levels increase, decomposition occurs at such a rate that carbon is quickly lost from the stream ecosystem. This finding is significant because carbon derived from such forest debris provides a year-round supply of potential energy to aquatic organisms, particularly in forest stream ecosystems where carbon available through algal growth is limited by a lack of light.  Similarly, the finding runs counter to the commonly observed increase in aquatic carbon levels in other freshwater ecosystems as a result of algal blooms following nutrient overloading.

The team carried out experiments in small, headwater streams running through forest in North Carolina, USA.  The first experiment ran for two years on two streams, and the second for three years in five streams.  Different combinations of nitrogen and phosphorous were added to some of the streams to simulate different land use scenarios, whilst other streams were left untouched as controls.

Results from the experiments showed that median carbon loss rates from the streams increased by 1.65 after moderate concentrations of nitrogen and phosphorous were added, and that the residence time of the carbon was roughly halved from 167 days under reference conditions to 75 days with nutrient addition.  Similarly, leaf litter levels were almost eight times higher in the unaltered streams after one year, in comparison to those where nitrogen and phosphorous had been added.

Rosemond and colleagues suggest that increased losses of carbon from aquatic ecosystems as a result of nutrient pollution is likely to be happening unobserved in freshwaters across the world.  However, because the process doesn’t have an easily visible result – as algal blooms do – it is largely unreported, and its effects on ecosystem services and ecological health and functioning understudied.  Perhaps ironically, leaf and wood debris in freshwaters and the microbes that live on them are important in taking up and regulating low levels of nutrients from the aquatic ecosystem.  As leaf and wood debris is decomposed more quickly as a result of nutrient overloading, the ecosystem’s capacity to take up further nutrients is decreased.

By providing new and previously unreported information on the interlinking of nutrient and carbon cycles in forest stream ecosystems, this study suggests that environmental policies designed to tackle nutrient pollution should not solely focus on its effects on algal blooms and eutrophication.  Instead, it seems that there is a pressing need to further study how carbon is lost from aquatic environments as a result of nutrient pollution, and then to implement suitable policies and indicators to help mitigate its effects on freshwater ecosystems.

Read the paper in full on Science Magazine Digital.

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