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  1. Can Responsible Grazing Make Beef Climate-Neutral?

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    • New research found that the greenhouse gases sequestered in one grass-fed system balanced out those emitted by the cows, but some meatless advocates are skeptical.
     

    There’s no denying Americans eat a lot of meat. In fact, the average U.S. citizen eats about 55 pounds of beef a year, including an estimated three hamburgers a week, and the United States Department of Agriculture (USDA) expects that amount to increase by about 3 percent by 2025. This heavy reliance on animal protein carries a big environmental footprint—livestock production contributes about 14.5 percent of global greenhouse gas (GHG) emissions, with beef constituting 41 percent of that figure, thanks to the methane cattle produce in the digestion process and the fact that overgrazing can release carbon stored in soils.

    ….A new five-year study that will be published in the May 2018 issue of the journal Agricultural Systems suggests that they can. Conducted by a team of researchers from Michigan State University (MSU) and the Union of Concerned Scientists (UCS), the study suggests that if cattle are managed in a certain way during the finishing phase, grassfed beef can be carbon-negative in the short term and carbon-neutral in the long term….

    ….“it is possible that long-term [adaptive multi-paddock grazing] AMP grazing finishing in the Upper Midwest could contribute considerably more to climate change mitigation and adaptation than previously thought.”

    Rather than using the common method of continuous grazing, in which cattle remain on the same pasture for an entire grazing season, the researchers used the more labor-intensive method of AMP, which entails moving the cattle at intervals ranging from days to months, depending on the type of forage, weather, time of year, and other considerations. A herd of adult cattle on MSU grazing land served as their test population.

    Though the study’s finding that strategic grazing can make a dent in the overall environmental impact of cattle runs counter to the widespread opinion among other researchers and climate activists, it is welcome news for advocates of regenerative agriculture.

    …. Tara Garnett, a food systems analyst and the founder of the Food Climate Research Network (FCRN) at the University of Oxford in England, calls the MSU work “a really useful study,” but also observes that it is “unclear how far this approach will lead to the same results elsewhere.” The study authors, too, are careful to stress that their results apply to Upper Midwestern conditions, and using a similar method in other ecosystem types will require further tailored study. They also acknowledge that while degraded land properly managed can take up large amounts of carbon, the soil will eventually reach equilibrium (meaning it will reach its carbon limit), and estimates of how long that takes vary widely.

    In addition, soil types and the many other aspects of climate and ecosystems in different regions require detailed understanding and granular management of grazing—something many beef producers may be unwilling to undertake. And grazing requires twice as much land as feedlots….

    …. One very promising practice, she said, is for ranchers to enlist farmers in the beef finishing phase. One farmer was initially very skeptical, but after he had grown a series of cover crops to rest his wheat fields and used cattle to “harvest” them, leaving the residue on the fields, he discovered that the soil was improving rapidly, Carman said. Reduced fertilizer and pesticide inputs, together with the income from the pasturage fees, makes the next wheat crop less expensive to grow.

    …. said Rowntree, “I hope our paper can give our industry, combined with policymakers, a lens that can potentially help. We’re not trying to pit one group against another.”

    Carman also acknowledges the complexity at hand, but feels the benefits to the soil she has seen are important to take into account. “Livestock are partly to blame for a lot of ecological problems we’ve got,” she said. “But we couldn’t repair these problems without livestock.”

    Paige L. Stanley, Jason E.Rowntree, David K.Beede, Marcia S.DeLonge, Michael W.Hamm. Impacts of soil carbon sequestration on life cycle greenhouse gas emissions in Midwestern USA beef finishing systems.  Agricultural Systems Volume 162, May 2018, Pages 249-258 https://doi.org/10.1016/j.agsy.2018.02.003

    See previous post on this here. 

    And related NPR story:

    A Grass-Roots Movement For Healthy Soil Spreads Among Farmers

    April 9 2018 America’s farmers are digging soil like never before. A movement for “regenerative agriculture” is dedicated to building healthier soil and could even lead to a new eco-label on food.

  2. Climate Change and Agriculture– Point Blue comments on the “Koronivia joint work on agriculture” (Dec 4/CP.23) submitted to the UNFCCC

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    March 30, 2018

    We at Point Blue submitted the attached recommendations last week on climate change and agriculture as an Observer to the United Nations Framework Convention on Climate Change (UNFCCC).

    See the document here:Point Blue (Observer) Submission on Issues Related to Agriculture per Korovinia* D4 CP23 UNFCCC March 30 2018 FIN

    See here for the UNFCCC Decision 4/COP23 inviting comments from parties and observers for the subsidiary science and technical bodies meetings in Bonn at the end of April 2018.

    See Presentations & Recordings from the Global Webinar  and more from my blog on the Koronivia joint work on agriculture decision from COP 23.  See also for more background: Koronivia: setting the stage for an agricultural transformation.

    See also for more information on the Koronivia joint work on agriculture: www.fao.org/climate-change/resources/learning/

    *Koronivia grass is a leafy, procumbent, creeping, stoloniferous perennial grass

  3. Advancing UN efforts on agriculture for climate change mitigation and adaptation– webinar recordings now available

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    • Agriculture is a special topic under the UNFCCC, cross-linking between adaptation and mitigation and covering all countries under the convention
    • In a recent webinar, participants discussed how the Koronivia Joint Work on Agriculture can help agricultural development address a triple threat: food security, climate resilience, and mitigation (read more here).

    March 5 2018 GFAR (Global Forum on Agricultural Research and Innovation) Presentations & Recordings from the Global Webinar

    In light of the recent adopted decision by the Parties at the Bonn Climate Change Conference in November 2017 known as the Koronivia* joint work on agriculture, the Food and Agriculture Organization of the United Nations and the CGIAR Research Program on Climate Change, Agriculture and Food Security (CCAFS) organized a global webinar to provide participants with a better understanding of the key opportunities and challenges involved in advancing Koronivia joint work on agriculture and an opportunity for dialogue on the topics identified in the Koronivia decision ahead of the Subsidiary Bodies for Scientific and Technological Advice (SBSTA) and Implementation (SBI) meetings to take place from 30 April – 10 May 2018 in Bonn, Germany.

    Through discussions it was noted that, many countries are already strongly affected by the adverse effects of climate change, including but not limited to droughts, pests and diseases. This requires support to increase resilience and sufficient climate finance in agriculture to make informed investments. In this sense, agriculture is a special topic under the UNFCCC, cross-linking between adaptation and mitigation and covering all countries under the convention. The Koronivia joint work is a chance to align the efforts of all stakeholders in the agricultural community – and we can take full advantage of this!

    Read blog

    Keynote speakers included representatives from the European Union, New Zealand, UNFCCC and Uruguay.

    Moderator: Julia Wolf, Natural Resources Officer, FAO Presentation | Recording

    Herwig Ranner, European Commission in the Directorate General for Agriculture and Rural Development Presentation | Recording

    Dirk Nemitz, Programme Officer for agriculture, forestry and other land-use at the UNFCCC Presentation | Recording

    Victoria Hatton,  Senior Policy Analyst, Ministry for Primary Industries, New ZealandPresentation | Recording

    Walter Oyhantcabal, Director of the Climate Change and Sustainability Unit in Uruguay’s Ministry of Livestock, Agriculture and Fisheries Presentation | Recording

    Bruce Campbell, Director of the CGIAR Research Program on Climate Change, Agriculture and Food Security Presentation | Recording

    Martial Bernoux, Coordinator of the Mitigation of Climate Change in Agriculture Programme, FAO Presentation | Recording

    As a follow up to the webinar, regional webinars are expected to be organized throughout the year. Please be on the lookout for these Koronivia regional dialogues!

    For more information on Koronivia joint work on agriculture, please visit: www.fao.org/climate-change/resources/learning/

    *Koronivia grass is a leafy, procumbent, creeping, stoloniferous perennial grass

  4. Nature-based solutions needed for better management of water, says UN report

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    • We need to increase our use of nature-based solutions – where we work more with nature – says a new report on global water management by the United Nations.
    • World Water Development Report 2018demonstrates how nature‐based solutions (NBS) use or mimic natural processes to enhance water availability (e.g., soil moisture retention, groundwater recharge), improve water quality (e.g., natural and constructed wetlands, riparian buffer strips), and reduce risks associated with water‐related disasters and climate change (e.g., floodplain restoration, green roofs). Read more / Download the report in English | Français | Español

    ….“We need new solutions in managing water resources,” says Audrey Azoulay, Director-General of UNESCO, “so as to meet emerging challenges to water security caused by population growth and climate change.”

    nature-based solutions - global water managementGreater use of nature-based solutions will help us toward a more holistic approach to managing global water resources. Image: CP/pixabay composite.

    The 2018 United Nations World Water Development Report featured recently at the 8th World Water Forum in Brasilia, Brazil.

    Holistic approach to water management

    The report argues that nature-based solutions are one of the many essential tools for moving toward “a more holistic approach to water management.”

    Nature-based solutions support the idea that water is not an isolated element but an inseparable part of a cycle of evaporation, precipitation, and absorption through the soil.

    Grasslands, forests, and wetlands – and the extensive vegetation cover that they provide – have a profound effect on the water cycle and by focusing on them we can do much to improve the amount and quality of water that is available.

    The report says that we need to make more use of environmental engineering that focuses on “green infrastructure” rather than just “grey infrastructure” solutions provided by traditional civil engineering.

    This does not mean that we do not continue to seek civil engineering solutions in the form of irrigation canals, reservoirs, and water treatment plants, but look to increase nature-based solutions to complement them.

    Benefits of ‘green infrastructure’

    Green infrastructure has much to offer water-intensive applications such as agriculture. For example, it can help to reduce soil erosion, pollution, and the amount of water required by making irrigation systems more efficient.

    An example of this is the change that has occurred in recent decades in the Indian state of Rajasthan, which suffered one of its worst droughts ever in 1986.

    In the years that followed, collaboration between an NGO and local communities established ways of harvesting water that regenerated forests and soils.

    As a result, forest cover in the state increased by 30 percent, groundwater levels went up several meters, and productivity of croplands improved.

    “For too long,” says Azoulay, “the world has turned first to human-built, or ‘grey’, infrastructure to improve water management. In so doing, it has often brushed aside traditional and Indigenous knowledge that embraces greener approaches.”….

  5. Small-scale farmers in a 1.5°C future: The importance of local social dynamics as an enabling factor for implementation and scaling of climate-smart agriculture

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    • Small-scale farmers can contribute to a 1.5°C future while adapting to climate change.
    • By using adaptation as an entry point, climate-smart ag (CSA) mitigation co-benefits can help reduce GHG.
    • Social capital generated through social networks can promote CSA scaling.
    • Social networks enable interactions across scales that can support spreading of CSA.
    April 2018 Current Opinion in Environmental Sustainability
    Climate-smart agriculture (CSA) has the potential to help farmers implement both adaptation and mitigation practices. The mitigation aspect of CSA is often not considered by farmers due to a high discount rate and, as such, adaptation is usually the priority concern…
    …Approaches such as climate-smart agriculture (CSA) [8] are intended to help to reorient agricultural systems to support food security under conditions of climate change and increased climate variability. Successful CSA consists of simultaneously achieving three goals or pillars according to FAO [8]: (i) sustainably increasing agricultural productivity to support equitable increases in incomes, food security and development; (ii) adapting and building resilience to climate change from the farm to national levels; and (iii) reducing or removing greenhouse gas (GHG) emissions where possible…

    …In agricultural research, scaling out is the objective to reach a wide number of farmers with improved practices [14], and scaling up occurs when institutional buy-in and policies are influenced at higher levels [15]. Though there are a wide array of challenges to scaling CSA, many of these can be addressed through technical, social, economic, and policy innovations [16]. Many of these are social processes and, though much of the work on adaptation has built on the ideas of capabilities associated with the “five capitals” (financial, natural, human, physical and social), we have perhaps lost sight of many of the complexities and nuances associated with social capital in particular [17]….

    ….In order to achieve a 1.5°C scenario, consideration of the characteristics of local networks should figure into the design of any community engagement effort [26••; 51 ;  52]. This is especially the case now that the call for “mainstreaming” synergistic adaptation-mitigation practices into development policy has become part of the standard refrain [24 ;  53]. With an understanding of how adaptation strategies synergize across scale as a function of the existing networks, a goal should be to leverage community strengths and design strategies that maximize mitigation as a direct co-benefit of the implementation of adaptation practices. This is even more important where “…motivation to pursue long-term, broad-based plans, and/or to respond to community priorities, may be constrained” [54••] (p.17). An examination of local networks thus has the potential to serve as something of a first pass for establishing both the relevance and transferability of different CSA practices at different scales, while simultaneously serving as basis for designing the corresponding institutional arrangements that will better facilitate the uptake of practices with mitigation co-benefits depending on local socio-ecological circumstances [49]…

    …We argue that achieving a 1.5°C scenario requires small-scale farmers’ contributions through the implementation of strategies that provide mitigation co-benefits and synergies linked to adaptation but that additional understanding of farmers network context is a critical first step. A 1.5°C future could consist of small-scale farmers increasing their resilience through low carbon adaptation to climate change, contributing to the global mitigation efforts. However, this will require CSA options to be implemented widely and rapidly, meaning uptake by most of the small-scale farmers as soon as possible. Explicit acknowledgement of how social capital and networks operate in relation to climate challenges thus has the potential to be a critical ingredient when designing and implementing CSA at scale.

    Social networks are likely a key to facilitate scaling up and out processes by enabling individuals and institutions to interact across scales, guiding their decision making processes [34••], and building social capital that spreads CSA strategies….

    Deissy Martinez-Baron, Guillermo Orjuela, Giampiero Renzoni, Ana María Loboguerrero Rodríguez, Steven D Prager.

    Current Opinion in Environmental Sustainability, Volume 31, April 2018, Pages 112–119, https://doi.org/10.1016/j.cosust.2018.02.013
  6. Climate Change Threatens Major Crops in California

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    • California produces over a third of the country’s vegetables and two-thirds of its fruits and nuts.
    • By the end of the century California’s climate will no longer be able to support the state’s major crops, including orchards.

    by Ahmel Ahmed KQED Feb 26 2018  read full article here

    California currently provides two-thirds of the country’s fruits and nuts, but according to a new study published Tuesday, by the end of the century California’s climate will no longer be able to support the state’s major crops, including orchards.

    The report, published in “Agronomy,” warns that the increased rate and scale of climate change is “beyond the realm of experience” for the agricultural community, and unless farmers take urgent measures, the consequences could threaten national food security.

    “For California, as an agricultural leader for various commodities, impacts on agricultural production due to climate change would not only translate into national food security issues but also economic impacts that could disrupt state and national commodity systems,” the report warns.

    The study, led by researchers from the University of California, Merced and Davis campuses, looked at past and current trends in California’s climate and examined what impact record low levels of snowpack, and extreme events such as drought will have on crop yields over time…

    Tapan B. Pathak , Mahesh L. Maskey, Jeffery A. Dahlberg, Faith Kearn, Khaled M. Bali and Daniele Zaccaria. Climate Change Trends and Impacts on California Agriculture: A Detailed Review. Agronomy 2018, 8(3), 25; doi:10.3390/agronomy8030025

    Abstract: California is a global leader in the agricultural sector and produces more than 400 types of commodities. The state produces over a third of the country’s vegetables and two-thirds of its fruits and nuts. Despite being highly productive, current and future climate change poses many challenges to the agricultural sector. This paper provides a summary of the current state of knowledge on historical and future trends in climate and their impacts on California agriculture. We present a synthesis of climate change impacts on California agriculture in the context of: (1) historic trends and projected changes in temperature, precipitation, snowpack, heat waves, drought, and flood events; and (2) consequent impacts on crop yields, chill hours, pests and diseases, and agricultural vulnerability to climate risks. Finally, we highlight important findings and directions for future research and implementation. The detailed review presented in this paper provides sufficient evidence that the climate in California has changed significantly and is expected to continue changing in the future, and justifies the urgency and importance of enhancing the adaptive capacity of agriculture and reducing vulnerability to climate change. Since agriculture in California is very diverse and each crop responds to climate differently, climate adaptation research should be locally focused along with effective stakeholder engagement and systematic outreach efforts for effective adoption and implementation. The expected readership of this paper includes local stakeholders, researchers, state and national agencies, and international communities interested in learning about climate change and California’s agriculture. View Full-Text

     

  7. Intensive agriculture caused cooler temps and more rain in US Midwest from 1950-2000

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    • The combination of improved seeds, fertilizers, and other practices, between 1950 and 2000 increased the annual yield of corn in the Midwest fourfold and soybeans 2x.
    • Denser plants with more leaf mass increased the amount of moisture released into the atmosphere that served to both cool the air and increase the amount of rainfall, the researchers suggest.
    • The regional cooling may have masked part of the warming effect that would have occurred over that period. That kind of intensification of agricultural yields achieved in the Midwest are unlikely to be repeated now.

    February 14 2018  read full ScienceDaily article here

    …The team showed that there was a strong correlation, in both space and time, between the intensification of agriculture in the Midwest, the decrease in observed average daytime temperatures in the summer, and an increase in the observed local rainfall. In addition to this circumstantial evidence, they identified a mechanism that explains the association, suggesting that there was indeed a cause-and-effect link between the changes in vegetation and the climatic effects.

    Eltahir explains that plants “breathe” in the carbon dioxide they require for photosynthesis by opening tiny pores, called stoma, but each time they do this they also lose moisture to the atmosphere. With the combination of improved seeds, fertilizers, and other practices, between 1950 and 2009 the annual yield of corn in the Midwest increased about fourfold and that of soybeans doubled. These changes were associated with denser plants with more leaf mass, which thus increased the amount of moisture released into the atmosphere. That extra moisture served to both cool the air and increase the amount of rainfall, the researchers suggest….

    …The findings suggest the possibility that at least on a small-scale regional or local level, intensification of agriculture on existing farmland could be a way of doing some local geoengineering to at least slightly lessen the impacts of global warming, Eltahir says. A recent paper from another group in Switzerland suggests just that.

    But the findings could also portend some negative impacts because the kind of intensification of agricultural yields achieved in the Midwest are unlikely to be repeated, and some of global warming’s effects may “have been masked by these regional or local effects. But this was a 20th-century phenomenon, and we don’t expect anything similar in the 21st century,” Eltahir says. So warming in that region in the future “will not have the benefit of these regional moderators.”

    Ross E. Alter, Hunter C. Douglas, Jonathan M. Winter, Elfatih A. B. Eltahir. Twentieth Century Regional Climate Change During the Summer in the Central United States Attributed to Agricultural Intensification. Geophysical Research Letters, 2018; DOI: 10.1002/2017GL075604

  8. Organic food provides significant environmental benefits to plant-rich diets

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    • Organic food provides significant, additional climate benefits for plant-based diets but not for diets with only moderate contribution from plant products.
    • Researchers caution that the environmental effects of production systems are not uniform and can be impacted by climate, soil types and farm management.
    • The study of more than 34,000 people is the first to investigate the environmental impacts of both food choices and farm production systems.
    February 9, 2018 read full ScienceDaily article here

    A major new study confirms that a diet high in fruit and vegetables is better for the planet than one high in animal products. The study also finds that organic food provides significant, additional climate benefits for plant-based diets, but not for diets with only moderate contribution from plant products. Published today in open access journal Frontiers in Nutrition, this is the first study to investigate the environmental impacts of both dietary patterns and farm production systems. It is also the first to investigate the environmental impact of organic food consumption using observed diets rather than models….

    …”Combining consumption and farm production data we found that across the board, diet-related environmental impacts were reduced with a plant-based diet — particularly greenhouse gas emissions,” says Louise Seconda. “The consumption of organic food added even more environmental benefits for a plant-based diet. In contrast, consumption of organic food did not add significant benefits to diets with high contribution from animal products and only moderate contribution from plant products.”

    However the researchers caution that the environmental effects of production systems are not uniform and can be impacted by climate, soil types and farm management.

    “We didn’t look at other indicators such as pesticide use, leaching and soil quality which are relevant to the environmental impacts of productions systems,” says Louise Seconda. “Therefore future studies could also consider these as well as supply chain and distribution impacts of food production…

    Camille Lacour, Louise Seconda, Benjamin Allès, Serge Hercberg, Brigitte Langevin, Philippe Pointereau, Denis Lairon, Julia Baudry, Emmanuelle Kesse-Guyot. Environmental Impacts of Plant-Based Diets: How Does Organic Food Consumption Contribute to Environmental Sustainability? Frontiers in Nutrition, 2018; 5 DOI: 10.3389/fnut.2018.00008

  9. Managing land to be cooler- including changing crops, moving to no till agriculture and lightening infrastructure – can reduce heat extremes by 2-3 degrees Celsius

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    • The researchers modeled how changing only the radiative properties of agricultural land and high population areas across North America, Europe and Asia would impact average temperatures, extreme temperatures and precipitation. The results showed small impacts on average temperatures, little change in precipitation — except in Asia — but significant reductions in extreme temperatures.
    • Albedo-related climate benefits of land management should be considered more prominently when assessing regional-scale climate adaptation and mitigation as well as ecosystem services.

    January 29, 2018 University of New South Wales read full ScienceDaily article here

    New research shows how simple, proven land-based geo-engineering measures can reduce the hottest days by 2-3 degrees C. Lightening buildings, roads and infrastructure in densely populated areas and changing crop types and using no till agricultural practices over farmland can all take the edge off the hottest days as climate change raises extreme temperatures…
    …Unlike many other climate-engineering methods proposed to tackle climate change, many of these regional modifications have already been tested and proven to work. Critically, this method has fewer risks compared with injecting aerosols into the atmosphere.“Extreme temperatures are where human and natural systems are most vulnerable. Changing the radiative properties of land helps address this issue with fewer side effects,” said Director of the ARC Centre of Excellence for Climate Extremes, Prof Andy Pitman.”This research suggests that by taking a regional approach, at least in temperate zones, policy and investment decisions can be pragmatically and affordably focused on areas of greatest need…….The researchers gained their results by modelling how changing only the radiative properties of agricultural land and high population areas across North America, Europe and Asia would impact average temperatures, extreme temperatures and precipitation.The results showed small impacts on average temperatures, little change in precipitation — except in Asia — but significant reductions in extreme temperatures…..”We must remember land-based climate engineering is not a silver bullet, it is just one part of a possible climate solution, and it would have no effects on global mean warming or ocean acidification. There are still important moral, economic and practical imperatives to consider that mean mitigation and adaption should still remain at the forefront of our approach to dealing with global warming.”…

    Sonia I. Seneviratne, Steven J. Phipps, Andrew J. Pitman, Annette L. Hirsch, Edouard L. Davin, Markus G. Donat, Martin Hirschi, Andrew Lenton, Micah Wilhelm, Ben Kravitz. Land radiative management as contributor to regional-scale climate adaptation and mitigation. Nature Geoscience, 2018; DOI: 10.1038/s41561-017-0057-5

    ABSTRACT: Greenhouse gas emissions urgently need to be reduced. Even with a step up in mitigation, the goal of limiting global temperature rise to well below 2 °C remains challenging. Consequences of missing these goals are substantial, especially on regional scales. Because progress in the reduction of carbon dioxide emissions has been slow, climate engineering schemes are increasingly being discussed. But global schemes remain controversial and have important shortcomings. A reduction of global mean temperature through global-scale management of solar radiation could lead to strong regional disparities and affect rainfall patterns. On the other hand, active management of land radiative effects on a regional scale represents an alternative option of climate engineering that has been little discussed. Regional land radiative management could help to counteract warming, in particular hot extremes in densely populated and important agricultural regions. Regional land radiative management also raises some ethical issues, and its efficacy would be limited in time and space, depending on crop growing periods and constraints on agricultural management. But through its more regional focus and reliance on tested techniques, regional land radiative management avoids some of the main shortcomings associated with global radiation management. We argue that albedo-related climate benefits of land management should be considered more prominently when assessing regional-scale climate adaptation and mitigation as well as ecosystem services.

  10. Wetlands provide landscape-scale reduction in nitrate pollution

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    • This research shows that wetland restoration could be one of the most effective methods for comprehensive improvement of water quality in the face of climate change and growing global demand for food.

    January 29, 2018 University of Minnesota College of Science and Engineering read full ScienceDaily article here

    A new study provides new insights to demonstrate that multiple wetlands or ‘wetland complexes’ within a watershed are extremely effective at reducing harmful nitrate in rivers and streams. These wetlands can be up to five times more efficient per unit area at reducing nitrate than the best land-based nitrogen mitigation strategies

    …Significant research findings include:

    • When stream flows are high, wetlands are five times more efficient per unit area at reducing nitrate than the best land-based conservation practices. Other common conservation practices are effective at lower flow conditions but overwhelmed with higher stream flows.
    • The arrangement of wetlands within a watershed is a key predictor of the magnitude of nitrate reduction. If wetlands intercept 100 percent of the drainage area, they are three times more effective at nitrate removal compared to interception of 50 percent of the drainage area.
    • Nitrate reduction due to ephemeral (temporary) wetlands, such as riparian floodplains and more geographically isolated wetlands (wetlands not connected to the river network by surface water), was measurable and was highest during high stream flows, when such features are hydrologically connected to surface water.

    ….Our work shows that wetland restoration could be one of the most effective methods for comprehensive improvement of water quality in the face of climate change and growing global demand for food,” said study co-author Jacques Finlay, a professor in the University of Minnesota’s Department of Ecology, Evolution and Behavior in the College of Biological Sciences….

    Amy T. Hansen, Christine L. Dolph, Efi Foufoula-Georgiou, Jacques C. Finlay. Contribution of wetlands to nitrate removal at the watershed scale. Nature Geoscience, 2018; DOI: 10.1038/s41561-017-0056-6