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Tag Archive: water

  1. Managing grazing lands to improve soils and promote climate change adaptation and mitigation: a global synthesis

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    • Findings reveal that a variety of management strategies have the potential to improve soil water infiltration rates, with possible benefits for soil carbon as well.
    • Researchers identified a shortage of well-replicated and detailed experiments in all grazing management categories, and call for additional research of both soil water and soil carbon properties for these critical agroecosystems

    DeLonge, M. and Basche, A., 2017. Managing grazing lands to improve soils and promote climate change adaptation and mitigation: a global synthesis. Renewable Agriculture and Food Systems, pp.1-12.

    Abstract

    The potential to improve soils to help farmers and ranchers adapt to and mitigate climate change has generated significant enthusiasm. Within this discussion, grasslands have surfaced as being particularly important, due to their geographic range, their capacity to store substantial quantities of carbon relative to cultivated croplands and their potential role in mitigating droughts and floods. However, leveraging grasslands for climate change mitigation and adaptation will require a better understanding of how farmers and ranchers who rely on them for their livelihoods can improve management and related outcomes.

    To investigate opportunities for such improvements, we conducted a meta-analysis of field experiments that investigated how soil water infiltration rates are affected by a range of management options: adding complexity to grazing patterns, reducing stocking rates or extended rest from grazing. Further, to explore the relationships between observed changes in soil water infiltration and soil carbon, we identified papers that reported data on both metrics. We found that in 81.9% of all cases, responses of infiltration rates to identified management treatments (response ratios) were above zero, with infiltration rates increasing by 59.3 ± 7.3%. Mean response ratios from unique management categories were not significantly different, although the effect of extended rest (67.9 ± 8.5%, n = 140 from 31 experiments) was slightly higher than from reducing stocking rates (42.0 ± 10.8%; n = 63 from 17 experiments) or adding complexity (34.0 ± 14.1%, n =17 from 11 experiments). We did not find a significant effect of several other variables, including treatment duration, mean annual precipitation or soil texture; however, analysis of aridity indices suggested that grazing management may have a slightly larger effect in more humid environments. Within our database, we found that 42% of complexity studies, 41% of stocking rate studies and 29% of extended rest studies also reported at least some measure of soil carbon. Within the subset of cases where both infiltration rates and carbon were reported, response ratios were largely positive for both variables (at least 64% of cases had positive mean response ratios in all management categories).

    Overall, our findings reveal that a variety of management strategies have the potential to improve soil water infiltration rates, with possible benefits for soil carbon as well. However, we identified a shortage of well-replicated and detailed experiments in all grazing management categories, and call for additional research of both soil water and soil carbon properties for these critical agroecosystems.

  2. 20 percent more trees in megacities would mean cleaner air and water, lower carbon and energy use

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    18 Jan 2018   read full ScienceDaily article here

    Planting 20 percent more trees in our megacities would double the benefits of urban forests, like pollution reduction, carbon sequestration and energy reduction. The authors of the study say city planners, residents and other stakeholders should start looking within cities for natural resources and conserve the nature in our urban areas by planting more trees….

    T. Endreny, R. Santagata, A. Perna, C. De Stefano, R.F. Rallo, S. Ulgiati. Implementing and managing urban forests: A much needed conservation strategy to increase ecosystem services and urban wellbeing. Ecological Modelling, 2017; 360: 328 DOI: 10.1016/j.ecolmodel.2017.07.016

  3. Strikingly dry conditions persist; Thomas Fire now largest California wildfire

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    by Daniel Swain December 24, 2017 read full CA Weather Blog post here

    Bone dry in Southern California, and below average precip throughout CA

    All of California is now experiencing well-below-average precipitation for the season to date. Southern California has seen almost no precipitation at all…

    Why has California been so dry? (Regular blog visitors already know where I’m going with this.) Well, a remarkably persistent zone of atmospheric pressure has been present more often than not across the region for the past few months. ….More recently, the bigger & stronger West Coast ridge has pushed the Pacific storm track even further north. Remarkably, this powerful ridge has forced several very moist atmospheric river storms over the mid-Pacific to make a hard “left turn” over the open ocean–veering directly northward and bringing almost inconceivably heavy snowfall to the coastal mountains of southern Alaska.

    Thomas Fire becomes largest wildfire in modern California history–in December

    The Thomas Fire has become the largest wildfire in modern California history–in December. (Via NASA)

    ….While December wildfires are not unheard of in this part of the world, the extent and severity of the December 2017 fires in SoCal really is unprecedented in California history. The Thomas Fire–which has now burned nearly 275,000 acres and over a thousand structures in Ventura and Santa Barbara counties–yesterday became the single largest wildfire in modern California history. That this dubious milestone was reached in December, which is typically the midst of the California rainy season, is truly extraordinary. Indeed, recent months have brought not only near-record low precipitation, but also record-high temperatures across a wide swath of SoCal….

    …..While long-term humidity records are hard to come by in most spots, all signs suggest that these were at or near record-low humidity values for many of these recording stations (and certainly for the time of year).

    Is this (another) return of the Ridiculously Resilient Ridge?

    Persistent high pressure ridging over the American West has kept conditions unusually warm and dry so far this autumn and early winter, especially across Southern California and Arizona. (NOAA via ESRL)……we’re not in Triple R [ridiculously resilient ridge] territory quite yet, but we’re getting close. We have certainly witnessed the return of resilient ridging near California, but I don’t think we’ve yet reached the “ridiculous” level of multi-month persistence that occurred during the height of the recent California drought. Should present conditions persist through January, and if seasonal precipitation has not started to recover from its early deficit by that time, I may have to revise that answer.

     

    …The not-so-good news: parts of Southern California that depend exclusively on local water supplies (such as much of Santa Barbara and Ventura counties) never really recovered from the last drought, and these regions remain quite susceptible to the impacts of drought re-intensification. And even further north, forested regions remain quite stressed as a result from the previous multi-year drought, and tree mortality in the Sierra Nevada remains far above historically observed levels.

    Unfortunately, 2+ weeks of unusually dry conditions still probable….The “Warm West/Cool East” pattern discussed in the previous post is still quite prominent over North America. The present West Coast dryness is largely consistent with seasonal model predictions for this winter, and those same models presently suggest that the present pattern is likely to persist for much of the California rainy season.All of this is to say: it’s still too early to say whether we’re headed into a new drought, though there are some compelling signs that we may be (especially in Southern California). And even in a dry year, California can still experience big storms and very wet months. But at this point, it probably makes sense to start thinking about the possibility of yet another big swing in California–from drought, to flood, and then (perhaps) back again.

  4. Changing climate, changing cities: Jakarta Is Sinking So Fast, It Could End Up Underwater in 10 Years

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  5. New Map of Worldwide Croplands Supports Food and Water Security- USGS

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    November 14, 2017 see full USGS press release here

    ….With the global population nearing the 7.6 billion mark and expected to reach 10 billion by 2050, it is of increasing importance to understand and monitor the state of agriculture across the world in great detail. This new research is useful to international development organizations, farmers, decision makers, scientists and national security professionals.

    This map is a baseline and starting point for higher level assessments, such as identifying which crops are present and where, when they grow, their productivity, if lands are left fallow and whether the water source is irrigated or rain fed,” said Thenkabail. “Comparisons can be made between the present and past years as well as between one farm and another. It is invaluable to know the precise location of croplands and their dynamics to lead to informed and productive farm management.”

    …Not only does this map and accompanying data have significant food security implications, but it is also critical as a baseline for assessing water security. Nearly 80 percent of all human water use across the world goes towards producing food, and this research provides insight on “crop per drop,” which is an assessment of the amount of crops produced per unit of water….

  6. Finally, a focus on saving the great forests of the Sierra. But is it too late? SacBee Editorial

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    • “There is an urgent need to reform policy and management to ensure that Californians continue to benefit from these forests for generations to come,” a new Public Policy Institute of California report says
    • Reducing forest density could have the side benefit of increasing run-off by as much as 9 percent, filling streams and rivers for the good of fisheries and for residential, agriculture and industrial use, the PPIC report says.

    Sacramento Bee Editorial  September 21, 2017 read full SacBee editorial here

    We Californians take for granted the great forests of the Sierra Nevada. It is where we ski and hike, and breathe fresh air, and it’s the primary source of our water.

    It’s all at risk. Drought and bark beetle infestation are the proximate cause of death of more than 100 million trees in California since 2010. But the forests were weakened by climate change, combined with mismanagement that includes well-intentioned wildfire prevention efforts and logging in past decades of old-growth trees, which are most resistant to fire and disease.

    [Governor] Brown and the Legislature approved another $225 million in cap-and-trade revenue, reserved for the fight against climate change, for forests. That underscored one of California’s inconvenient truths. Like refineries, diesel engines and cars powered by internal combustion, burning and decaying forests spew greenhouse gases.

    In April, the Governor’s Tree Mortality Task Force reported that the 2013 Rim Fire at Yosemite emitted 12.06 million tons of carbon dioxide, three times more than all the greenhouse gas reductions achieved that year in all other sectors in California. Worse, the detritus decomposing in the burn area will unleash four times that amount of greenhouse gas in coming decades.

    In much of the 15 million acres of mountains from Kern to Siskiyou counties, forests are choking with 400 sickly trees per acre, four times the number in healthy forests. Tools to heal the forests are at hand, but forest management is fraught.

    …Some environmentalists oppose logging, while some conservative politicians advocate unraveling environmental restrictions to allow for far more logging. Neither extreme is helpful. Flexibility is needed. The Clean Air Act could, for example, allow for the use of prescribed fires.

    …Reducing forest density could have the side benefit of increasing run-off by as much as 9 percent, filling streams and rivers for the good of fisheries and for residential, agriculture and industrial use, the PPIC report says.

    The report says the cost of wise forest management might not be astronomical. In time, it might pay for itself, assuming mills are retooled or built to accommodate smaller and mid-size timber. Such mills could provide jobs in parts of the state where unemployment is chronically high.

    …Our re-engineered state of 40 million people faces many problems. The water delivery system is oversubscribed and antiquated. Billions of dollars should be spent to reinforce California against floods.

    But there is cause for optimism. Laird last month announced the Tahoe-Central Sierra Initiative with other top officials, and some significant environmental groups are joining longtime advocates to focus on Sierra restoration. There is some support in Congress for wiser forest management.

    And now comes an infusion of state money, not to be taken for granted, and none too soon.

  7. Plastic fibres found in tap water around the world, study reveals

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    • Tests show billions of people globally are drinking water contaminated by plastic particles, with 83% of samples found to be polluted
    • Almost 300m tonnes of plastic is produced each year and, with just 20% recycled or incinerated, much of it ends up littering the air, land and sea. A report in July found 8.3bn tonnes of plastic has been produced since the 1950s, with the researchers warning that plastic waste has become ubiquitous in the environment.

    by   Sept 5 2017 Guardian UK read full article here

    Microplastic contamination has been found in tap water in countries around the world, leading to calls from scientists for urgent research on the implications for health.

    Scores of tap water samples from more than a dozen nations were analysed by scientists for an investigation by Orb Media, who shared the findings with the Guardian. Overall, 83% of the samples were contaminated with plastic fibres.

    The US had the highest contamination rate, at 94%, with plastic fibres found in tap water sampled at sites including Congress buildings, the US Environmental Protection Agency’s headquarters, and Trump Tower in New York. Lebanon and India had the next highest rates….

    ….The new analyses indicate the ubiquitous extent of microplastic contamination in the global environment. Previous work has been largely focused on plastic pollution in the oceans, which suggests people are eating microplastics via contaminated seafood….

    A magnified image of clothing microfibres from washing machine effluent.
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    A magnified image of clothing microfibres from washing machine effluent. One study found that a fleece jacket can shed as many as 250,000 fibres per wash. Photograph: Courtesy of Rozalia Project

    Microplastics are also known to contain and absorb toxic chemicals and research on wild animals shows they are released in the body…His research has shown microplastics are found in a third of fish caught in the UK…

    …The scale of global microplastic contamination is only starting to become clear, with studies in Germany finding fibres and fragments in all of the 24 beer brands they tested, as well as in honey and sugar. In Paris in 2015, researchers discovered microplastic falling from the air, which they estimated deposits three to 10 tonnes of fibres on the city each year, and that it was also present in the air in people’s homes….

     

     

  8. Dynamic conservation for migratory waterbirds – new publication co-authored by TNC, Cornell, Point Blue

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    Coauthored by scientists from: The Nature Conservancy of California, Cornell Lab of Ornithology, Point Blue Conservation Science (Matt Reiter, Sam Veloz, Catherine Hickey and Nathan Elliott) and University of Melbourne.

    Abstract: In an era of unprecedented and rapid global change, dynamic conservation strategies that tailor the delivery of habitat to when and where it is most needed can be critical for the persistence of species, especially those with diverse and dispersed habitat requirements. We demonstrate the effectiveness of such a strategy for migratory waterbirds.

    We analyzed citizen science and satellite data to develop predictive models of bird populations and the availability of wetlands, which we used to determine temporal and spatial gaps in habitat during a vital stage of the annual migration. We then filled those gaps using a reverse auction marketplace to incent qualifying landowners to create temporary wetlands on their properties. This approach is a cost-effective way of adaptively meeting habitat needs for migratory species, optimizes conservation outcomes relative to investment, and can be applied broadly to other conservation challenges.

  9. Urban land transformation and electricity production impact river ecosystems on much larger scale

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    • The results indicate that urban land transformation and electricity production together affect seven percent of U.S. streams, which influence habitats for more than 60 percent of all North American freshwater fish, mussel, and crayfish species.

    August 23, 20 DOE/Oak Ridge National Laboratory  Read full ScienceDaily article here

    New mapping methods can help urban planners minimize the environmental impacts of cities’ water and energy demands on surrounding stream ecologies.

    Using streamflow data from the U.S. Geological Survey, the researchers mapped changes to natural hydrology to assess how infrastructure development and competition over water resources affects the environment at a national scale.

    The results indicate that urban land transformation and electricity production together affect seven percent of U.S. streams, which influence habitats for more than 60 percent of all North American freshwater fish, mussel, and crayfish species.

    …In the five cities, urban land transformations negatively affected more stream length overall than any other factor considered, including electricity production. The introduction of roads, buildings, and other impervious surfaces alters the natural water cycle, displaces water supplies for downstream communities and can threaten the loss of rich and diverse aquatic species.

    …”Both the source and solution to global environmental challenges may lie in the hands of cities. Unfortunately, the changes we discuss are highly transformative, not cheap,” McManamay said. “Our goal here is to give cities a way to look at the big picture, so to speak, and to generate metrics that will help them move toward more environmentally sound policies as they continue to develop.

    Ryan A. McManamay et al. US cities can manage national hydrology and biodiversity using local infrastructure policy. Proceedings of the National Academy of Sciences, 2017; 201706201 DOI: 10.1073/pnas.1706201114

  10. Measuring the Benefits of Regenerative Agriculture- TomKat Ranch and Ag Tech

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    • once the benefits of regenerative ranching can be fully quantified – through soil carbon measurements, forage density, and more [working with Point Blue and others]– it could become a mainstay of both ranching and soil management.
    • Holistic or planned grazing can lead to to increased forage production, soil fertility, resistance to drought, water retention, and sequestration of carbon into the soil..
    • TomKat Ranch is betting that the rise of precision agriculture and big data technologies could help prove the financial viability of regenerative ranching, as well as the environmental benefits/

    August 9 2017 read full article at AgFunder News/Successful Farming

    Regenerative agriculture is a method of farming that aims to restore the fertility of the soil and the overall health of the land it’s conducted on….consistent with sustainable agriculture practices, … limiting the use of synthetic inputs like pesticides and fertilizers and limiting tillage of the soil, which can negatively impact soil health. Often, regenerative agriculture involves livestock.

    This might seem confusing if you’ve read the countless headlines that livestock farming is the biggest culprit of greenhouse gas emissions – according to the FAO it accounts for 18% of emissions – but there is a school of thought that’s gathering momentum and evidence that managing livestock in certain ways not only can reduce the negative impact of livestock farming on the environment but also can actually regenerate the land and have a positive impact….’

    Through what’s called holistic planned grazing, or rotational grazing, ranchers strategically move their cattle around the land so that no one area is too depleted, yet every inch of rangeland is trimmed and fertilized by the cows.

    These methods can lead to increased forage production, soil fertility, resistance to drought, water retention, and the sequestration of carbon from the atmosphere into the soil, among other benefits.

    TomKat Ranch, a proponent of regenerative ranching, is betting that the rise of precision agriculture and big data technologies could help prove the financial viability of regenerative ranching, as well as the environmental benefits. The idea of adding only what is absolutely necessary to an agricultural process is a fundamental principle behind precision farming, and TomKat is working to apply these principles to cattle grazing.

    Kevin Watt, land and livestock manager at TomKat Ranch in California, thinks that once the benefits of regenerative ranching can be fully quantified – through soil carbon measurements, forage density, and more – it could become a mainstay of both ranching and soil management.

    “When you’re doing something that is regenerative, you’re basically saying that your productive asset should not be losing value. Your productive asset should be gaining value, and that appeals to everybody,” Watt told AgFunderNews….We caught up with Watt at the Forbes Agtech Summit in Salinas, California, to find out what kind of technology he’ll need to make his case and what challenges are standing in the way…

    …”We have onsite conservation scientists from Point Blue Conservation Science doing very meticulous technician-driven soil tests, vegetation surveys, and wildlife surveys that we can compare to our very rigorous management records and see what strategies grow us more grass, which ones grow us more beef, which ones keep our streams running longer. For every 1% of soil organic matter change or growth, we get an extra 25,000 gallons of water per acre being stored. That’s a USDA figure so people know about this.

    Climate-SH_Infographicsmall.jpg

    We’ve learned that if you can get that feedback from your landscape, whether or not you share a philosophical interest in environmentalism or humane treatment of animals, you start to see that it really makes sense to evolve with your landscape; to see what the ROI is on every one of your management choices. That’s why precision ranching could be so transformative…”