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Tag Archive: agriculture

  1. Groundwater pumping can increase arsenic levels in San Joaquin Valley irrigation and drinking water; recovery possible if withdrawals stop

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    • Satellite-derived measurements of ground sinking could predict arsenic concentrations in groundwater and serve as an early warning system to prevent dangerous levels of arsenic contamination in aquifers with certain characteristics worldwide.
    • Researchers found signs that aquifers contaminated as a result of overpumping can recover if withdrawals stop.

    June 5, 2018 Stanford University Read full ScienceDaily article here

    Pumping an aquifer to the last drop squeezes out more than water. A new study finds it can also unlock dangerous arsenic from buried clays — and reveals how sinking land can provide an early warning and measure of contamination.

    Now research published in the journal Nature Communications suggests that as pumping makes the ground sink, it also unleashes an invisible threat to human health and food production: It allows arsenic to move into groundwater aquifers that supply drinking water for 1 million people and irrigation for crops in some of the nation’s richest farmland…

    …Importantly, the group found signs that aquifers contaminated as a result of overpumping can recover if withdrawals stop. Areas that showed slower sinking compared to 15 years earlier also had lower arsenic levels….

    …When water pumping slows enough to put the brakes on subsidence — and relieve the squeeze on trapped arsenic — clean water soaking in from streams, rain and natural runoff at the surface can gradually flush the system clean.

    However, study co-author Rosemary Knight, a professor of geophysics and affiliated faculty at the Woods Institute, warns against banking too much on a predictable recovery from overpumping. “How long it takes to recover is going to be highly variable and dependent upon so many factors,” she said….

    Ryan Smith, Rosemary Knight, Scott Fendorf. Overpumping leads to California groundwater arsenic threat. Nature Communications, 2018; 9 (1) DOI: 10.1038/s41467-018-04475-3

  2. Sediment and nutrient storage in a beaver-engineered wetland

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    • Beaver ponds were shown to hold large volumes of sediment and associated nutrients.
    • The beavers’ enclosure, roughly the size of three (American) football fields and situated on a stream below a farm, originally contained one small pond… and is now a wetland mosaic regulated by dams and canals, and the ponds are slowly filling with sediment — 101 tons of it to date, estimate Brazier’s team.
    • Some of that sediment was generated by the beavers’ own digging. The vast majority, though, is eroded soil from the adjacent farmland. Altogether the sediments contain 16 tons of carbon — representing, were every last ounce of it sequestered permanently, the average yearly carbon emissions of six British citizens.

    Puttock et al. “Sediment and Nutrient Storage in a Beaver Engineered Wetland. Earth Surface Processes and Landforms.” Earth Surface Processes and Landforms, 2018.

    AND see this article about this study: The tremendous benefits provided by just one beaver family Anthropocene Magazine May 30 2018


    Beavers, primarily through the building of dams, can deliver significant geomorphic modifications and result in changes to nutrient and sediment fluxes. Research is required to understand the implications and possible benefits of widespread beaver reintroduction across Europe. This study surveyed sediment depth, extent and carbon/nitrogen content in a sequence of beaver pond and dam structures in South West England, where a pair of Eurasian beavers (Castor fiber) were introduced to a controlled 1.8 ha site in 2011. Results showed that the 13 beaver ponds subsequently created hold a total of 101.53 ± 16.24 t of sediment, equating to a normalised average of 71.40 ± 39.65 kg m2. The ponds also hold 15.90 ± 2.50 t of carbon and 0.91 ± 0.15 t of nitrogen within the accumulated pond sediment.

    The size of beaver pond appeared to be the main control over sediment storage, with larger ponds holding a greater mass of sediment per unit area. Furthermore, position within the site appeared to play a role with the upper‐middle ponds, nearest to the intensively‐farmed headwaters of the catchment, holding a greater amount of sediment. Carbon and nitrogen concentrations in ponds showed no clear trends, but were significantly higher than in stream bed sediment upstream of the site.

    We estimate that >70% of sediment in the ponds is sourced from the intensively managed grassland catchment upstream, with the remainder from in situ redistribution by beaver activity. While further research is required into the long‐term storage and nutrient cycling within beaver ponds, results indicate that beaver ponds may help to mitigate the negative off‐site impacts of accelerated soil erosion and diffuse pollution from agriculturally dominated landscapes such as the intensively managed grassland in this study.


    Results presented in this paper illustrate that beavers can exert a significant impact upon sediment and nutrient storage. Beaver ponds were shown to hold large volumes of sediment and associated nutrients. Results also suggest that, whilst pond age and deposition in a dam–pond sequence may play a role in sediment and nutrient storage, the clearest control was pond size, with larger ponds holding more sediment per unit area.

    Unlike most previous work, this study focused on a site located within an intensively managed grassland landscape. It was inferred that the majority of sediment trapped in the ponds originated from erosion in the upstream intensively managed grassland catchment, therefore, beaver dams mitigated the loss of this sediment downstream. While further understanding of the long‐term stability of sediment and nutrient storage in beaver ponds is now required, findings presented in this study have important implications for understanding the role beavers may play as part of catchment management strategies.

  3. Hemp Legalization Poised to Transform Agriculture in Arid West

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    • Since 2014 it has been legal to grow hemp, marijuana’s non-psychoactive cousin, in small “research” batches. Legislation passed this year could open the door to full-scale farming of this versatile, drought-tolerant plant.

    Matt Weiser May 16 2018 Read full NewsDeeply article here

    …..Hemp can be grown to harvest on about half as much water as corn can, for example. Hemp also tolerates a wide variety of soils and temperatures, requires no pesticides and grows extremely fast, soaring to as much as 20ft in 100 days.

    Thus, if hemp eventually replaces other crops across large acreages, it could free up precious water supplies in the arid West for other uses. This could become especially important with climate change expected to shrink Western mountain snowpacks…

    ….CBD oil products are currently the main market for hemp growers in the United States. But there are more than 25,000 other products that can be made from hemp, given the right processing equipment, including food for people and livestock, fabrics, building materials, ethanol and biodiesel.

    For all these reasons, the 2014 Farm Bill allowed hemp cultivation to resume in America for “research” purposes. The law required states to set up a permitting process, and an individual farmer’s crop could cover no more than 50 acres….

    ….Hemp farming may get a big boost this year with legislation in Congress that would fully legalize it as an agricultural crop. The bill has bipartisan support and was introduced by the most powerful Republican in Congress, Senator Mitch McConnell of Kentucky. If passed, it would eliminate all legal impediments to hemp-growing and make farmers eligible for many of the benefits available to other crops, including crop insurance and federal research grants.

  4. Beaver dams reduce soil loss and trap pollutants

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    • Researchers found that beaver dams trapped more than 100 tonnes of sediment, 70% of which was soil, which had eroded from ‘intensively managed grassland’ fields upstream.
    • This sediment contained high concentrations of nitrogen and phosphorus, which are nutrients known to create problems for the wildlife in rivers and streams and which also need to be removed from human water supplies to meet drinking-quality standards.

    May 9, 2018 University of Exeter Read full ScienceDaily article here

    Beavers could help clean up polluted rivers and stem the loss of valuable soils from farms, new research shows.

    …”we are heartened to discover that beaver dams can go a long way to mitigate this soil loss and also trap pollutants which lead to the degradation of our water bodies. Were beaver dams to be commonplace in the landscape we would no doubt see these effects delivering multiple benefits across whole ecosystems, as they do elsewhere around the world.”

    …”Our partnership with Exeter University working on both our fenced and unfenced beaver trials is revealing information which shows the critical role beavers can play, not only for wildlife, but the future sustainability of our land and water. It is truly inspiring to have our observations confirmed by detailed scientific investigations.”

    Alan Puttock, Hugh A. Graham, Donna Carless, Richard E. Brazier. Sediment and Nutrient Storage in a Beaver Engineered Wetland. Earth Surface Processes and Landforms, 2018; DOI: 10.1002/esp.4398

  5. 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

    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.

  6. 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:

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

  7. 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:

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

  8. 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.”….

  9. 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,
  10. 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