Tag Archives: green infrastructure

January 2016 in Review

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I’m going to try picking the three most frightening posts, three most hopeful posts, and three most interesting posts (that are not particularly frightening or hopeful) from January.

3 most frightening posts

  • Paul Ehrlich is still worried about population. 82% of scientists agree.
  • Thomas Picketty (paraphrased by J. Bradford Delong) says inequality and slow growth are the norm for a capitalist society. Joseph Stiglitz has some politically difficult solutions: “Far-reaching redistribution of income would help, as would deep reform of our financial system – not just to prevent it from imposing harm on the rest of us, but also to get banks and other financial institutions to do what they are supposed to do: match long-term savings to long-term investment needs.”
  • Meanwhile, government for and by big business means the “Deep State” is really in control of the U.S. In our big cities, the enormous and enormously dysfunctional police-court-prison system holds sway over the poor.

3 most hopeful posts

3 most interesting posts

  • There are some arguments in favor of genetically modified food – they have increased yields of some grains, and there is promise they could increase fish yields. 88% of scientists responding to a Pew survey said they think genetically modified food is safe, but only 37% of the U.S. public thinks so. In other biotech news, Obama’s State of the Union announced a new initiative to try to cure cancer. In other food news, red meat is out.
  • Not only is cash becoming obsolete, any physical form of payment at all may become obsolete.
  • The World Economic Forum focused on technology: “The possibilities of billions of people connected by mobile devices, with unprecedented processing power, storage capacity, and access to knowledge, are unlimited. And these possibilities will be multiplied by emerging technology breakthroughs in fields such as artificial intelligence, robotics, the Internet of Things, autonomous vehicles, 3-D printing, nanotechnology, biotechnology, materials science, energy storage, and quantum computing.”

 

An R package for modelling actual, potential and reference evapotranspiration

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I and some people I know will be very excited about this. Which means I know some very weird people.

An R package for modelling actual, potential and reference evapotranspiration

Evapotranspiration (ET) is a vital component of the hydrological cycle and there are a large number of alternative models for representing ET processes. However, implementing ET models in a consistent manner is difficult due to the significant diversity in process representations, assumptions, nomenclature, terminology, units and data requirements. An R package is therefore introduced to estimate actual, potential and reference ET using 17 well-known models. Data input is flexible, and customized data checking and pre-processing methods are provided. Results are presented as summary text and plots. Comparisons of alternative ET estimates can be visualized for multiple models, and alternative input data sets. The ET estimates also can be exported for further analysis, and used as input to rainfall-runoff models.

a dream of spring, or plant geeks, seeds and where to find them

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I’m enjoying this book by Eric Toensmeier, part of the new (at least to me) generation of American permaculture enthusiasts.

I might not enjoy it as much if I hadn’t already read Edible Forest Gardens, but this book is in part a narrative of how that book came about. These are the kinds of things gardeners read in January (at least, until George R.R. Martin gets around to publishing A Dream of Spring…)

I like this paragraph about being inspired by native peoples’ management of wild landscapes:

As a budding ecologist in the 1970s and 1980s, I learned that the best we can possibly do as environmentalists is to minimize our impact on nature. The ideal footprint would be no footprint at all. That doesn’t really give us a lot of room to breathe, and with that as a model, it’s easy to see why the environmental movement has not won wider acceptance. The most profound thing I have learned from indigenous land management traditions is that human impact can be positive – even necessary – for the environment. Indeed it seems to me that the goal of an environmental community should not be to reduce our impact on the landscape but to maximize our impact and make it a positive one, or at the very least to optimize our effect on the landscape and acknowledge that we can have a positive role to play.

Urban forestry is a good place to start with this vision, and there is some energy behind that (although also a fair amount of negativity and cynicism opposing it). Once we get the trees we want, we can decide that it is okay for a city to have a shrub layer and an herbaceous layer too, and we can work on those. There is also a fair amount of energy and funding behind water management in cities. Once we have the soil and the plants, it seems fairly obvious to bring the water to them. Again there is some cynicism and negativity out there, and a divide between energetic but sometimes scientifically challenged hippies, and the oh-so-practical but oh-so-cynical engineers, who actually could make all this work if they put their minds to it.

One last thing on this book – it has an appendix which lists some sources of seeds and plants I wasn’t familiar with. This is an area where Google lets us down, because these companies sell all sorts of interesting things that I have been looking for, and the typical search algorithms have not been getting me there.

  • Oikos Tree Crops – focuses on native nut and fruit trees, also has some hard-to-find perennials like several varieties of Sunchoke tubers
  • Kitazawa Seed Company – focuses on seeds of Asian vegetables – lots of Thai chilies, basils and eggplant varieties here! I’m also interested in “Malabar Spinach”, which sounds like it could provide me salads all summer with minimal effort, as long as I eat it fast enough so it doesn’t eat my house. (I’m also interested in hardy Kiwis and hops, but these woody vines are a little scarier because if you let them go, you might need a chain saw to remove them.)
  • Evergreen Seeds – another source of Asian vegetable seeds
  • Edible Landscaping – these guys will ship some hard-to-find fruit tree species, like Asian persimmons and pears
  • Fedco Seeds – all kinds of vegetables and fruits, seeds and plants
  • Food Forest Farm – Toensmeier’s site, with a limited selection of very interesting plants
  • Fungi Perfecti – what it sounds like, mushrooms
  • High Mowing Organic Seeds – another general purpose seed company
  • Logee’s – obscure tropical plants, looks great for the houseplant and patio gardener, not so focused on edibles
  • One Green World – lots of fruits, nuts, and berries, focus on the Pacific Northwest
  • Raintree Nursery – more fruit and nut trees
  • Richters – lots of vegetable and herb seeds

December 2015 in Review

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Now it’s time to review December 2015, before we get on to reviewing 2015 as a whole.

Negative stories (-10):

  • Some car dealers are deliberately talking customers out of buying electric cars that they want, because the car dealer will make less money on oil changes. (-1)
  • Breaking news: we can’t believe everything we hear on the internet. Some of it is deliberate government and corporate propaganda, and some is “online filter bubbles” or marketing algorithms telling each of us only what we want to hear. Data used by all these algorithms is becoming more and more valuable. (-1)
  • Cyberattacks or superflares could destroy the U.S. electric grid. (-1)
  • Guns cause gut-wrenching, accidental deaths of children quite frequently in the U.S. The U.S. has a rate of violent assault 5-10 times higher than our close Anglo-American cousins, which in turn have higher rates than most of Europe and developed Asia. (-1)
  • I mused about whether it is really possible the U.S. could go down a fascist path. I reviewed Robert Paxton’s five stages of fascism. I am a little worried, but some knowledgeable people say not to worry. After reading Alice Goffman’s book On the Run though, one could conclude that a certain segment of our population is living in a fascist police state right now. There is some fairly strong evidence that financial crises have tended to favor the rise of the right wing in Europe. (-2)
  • After more than a decade of drought, there may not be enough water to sustain both Lake Powell and Lake Mead in the U.S. desert southwest. Some are suggesting draining Lake Powell. (-1)
  • This year’s “super El Nino” might have happened with or without climate change, but climate change made it more likely. I have to admit though I enjoyed sitting on my front porch in shorts on Christmas here in Philadelphia. (-1)
  • Jeffrey Sachs makes a pretty good case that the rise of violent religious fanaticism in the Middle East is largely the CIA’s fault. (-2)

Positive stories (+13):

    • Las Vegas is planning to go all renewable by 2017, mostly centralized solar. (+1)
    • Children have a natural aptitude for learning to recognize patterns. Now all we have to do is figure out which patterns we should be teaching them to recognize. (+1)
    • Some U.S. Presidential candidates want to invest in infrastructure, which is good. A national infrastructure plan might also be good. (+1)
    • Ericcson released some technology predictions for 2016 and beyond: Artificial intelligence will start to assist us without the need for smartphone screens. Virtual reality will start to come into its own for tech support, sports, dating, and shopping. And we will start to see more sensors embedded in our homes and eventually our bodies. (+1)
    • Trends in Ecology and Evolution made some technology predictions too: “managed bees as transporters of biological control agents, artificial superintelligence, electric pulse trawling, testosterone in the aquatic environment, building artificial oceanic islands, and the incorporation of ecological civilization principles into government policies in China”. (+1)
    • A serious but treatable infection can destroy a tumor. (+1)
    • Self-driving cars could drastically reduce the amount of land required for parking in cities. There are some moves toward car-free central cities around the world. (+3)
    • We had the Paris agreement. It is possible to be cynical about this agreement but it is the best agreement we have had so far. (+2)
    • New York City recently finished planting a million trees. (+2)

So we end the year on a positive note!

a million trees in New York

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New York City has managed to get a million new trees in the ground. Planting a bunch of trees seems like a no-brainer to many of us who are familiar with the logic and evidence in favor of green infrastructure. But this can still be hard for cities. There is a vocal minority of citizens who hate trees. They’re a minority, but did I mention they’re vocal? Then, trees are not a huge expense in the big picture of all the things cities have to pay for, like police, courts, prisons and pensions for example, but their planting and especially maintenance sometimes falls to city departments who are under-funded in good times and the first to get hit by budget cuts in bad times.

New York seems to have gotten past these challenges with strong planning, strong leadership to actually implement the plan, and partnering with a non-profit entity which could really focus on this one mission.

A collaboration between New York City’s parks department and conservation nonprofit New York Restoration Project (NYRP), the initiative just succeeded in planting 1 million new trees in the city this decade. The final tree was planted last month, two years ahead of schedule. While cities like Los Angeles, Boston and Denver have all set the same goal, New York is the first to meet it.

Beyond 220,000 new street trees, MillionTreesNYC planted in parks, on public and private property, and in all five boroughs, increasing the city’s urban canopy by 20 percent.

While the city planted 70 percent of the trees in parks and on streets, NYRP was tasked with getting the remainder into public and private spaces, including hospitals, libraries, churches, public housing developments and private yards.

I do have to point out that “a million trees planted” almost certainly does not mean a net gain of a million trees. While the program was being implemented, some trees must have died of “natural” causes (air pollution, heat stress, poor soil, lack of water). Some also must have been removed for legitimate reasons in the course of construction and infrastructure projects, and if my personal experience in Philadelphia is any guide, not all of those got replanted (the vocal minority of citizens having something to do with this). But all this is exactly why focusing on tree canopy is exactly the right way to look at it. By setting a tree canopy goal and periodically measuring where you are relative to it, you should know if you are replacing the trees lost to attrition at the right rate to keep your overall canopy from dropping.

emerald ash borer targets human arteries

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The emerald ash borer is supposed to kill trees, not people. But this study found that heart attack risk for women went up 25% when all the trees were killed by this pest. Lessons learned – (1) contact with nature lowers stress in an urban environment, (2) people grieve for lost trees. So cities should plant trees and take care of them. Just not all the same kind of trees, which is a basic principle of resilience. Sure, cities have limited money to spend, but there is a public health case to be made for spending some of it on trees.

nature and mental health

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From the Proceedings of the National Academy of Science:

Urbanization has many benefits, but it also is associated with increased levels of mental illness, including depression. It has been suggested that decreased nature experience may help to explain the link between urbanization and mental illness. This suggestion is supported by a growing body of correlational and experimental evidence, which raises a further question: what mechanism(s) link decreased nature experience to the development of mental illness? One such mechanism might be the impact of nature exposure on rumination, a maladaptive pattern of self-referential thought that is associated with heightened risk for depression and other mental illnesses. We show in healthy participants that a brief nature experience, a 90-min walk in a natural setting, decreases both self-reported rumination and neural activity in the subgenual prefrontal cortex (sgPFC), whereas a 90-min walk in an urban setting has no such effects on self-reported rumination or neural activity. In other studies, the sgPFC has been associated with a self-focused behavioral withdrawal linked to rumination in both depressed and healthy individuals. This study reveals a pathway by which nature experience may improve mental well-being and suggests that accessible natural areas within urban contexts may be a critical resource for mental health in our rapidly urbanizing world.

growing the urban forest

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This abstract in Restoration Ecology contains an interesting result: planting shrubs along with urban trees helps the trees. You might think the opposite, due to competition, but I have heard this before. One theory I’ve heard is that shrubs help establish beneficial fungi in the soil that pave the way for healthy trees. It shouldn’t be too surprising, when this is exactly the succession that will occur in an abandoned field over time, given enough rainfall and not too much fire.

Compost also helps trees, which might be surprising to some professional engineers but not to any amateur gardener (luckily, some of us are both!). Still, in urban stormwater management we engineers are often encouraged to plant trees and other vegetation, but to minimize organic matter because the same nutrients that trees need can become water pollutants if they find their way downstream. It’s a delicate balance. Civil, “environmental”, and geotechnical engineers aren’t good at finding it because it is not part of our typical training. We need the agriculture, forestry, and soil science types to help us with this.

Forests are vital components of the urban landscape because they provide ecosystem services such as carbon sequestration, storm-water mitigation, and air-quality improvement. To enhance these services, cities are investing in programs to create urban forests. A major unknown, however, is whether planted trees will grow into the mature, closed-canopied forest on which ecosystem service provision depends. We assessed the influence of biotic and abiotic land management on planted tree performance as part of urban forest restoration in New York City, U.S.A. Biotic treatments were designed to improve tree growth, with the expectation that higher tree species composition (six vs. two) and greater stand complexity (with shrubs vs. without) would facilitate tree performance. Similarly, the abiotic treatment (compost amendment vs. without) was expected to increase tree performance by improving soil conditions. Growth and survival was measured for approximately 1,300 native saplings across three growing seasons. The biotic and abiotic treatments significantly improved tree performance, where shrub presence increased tree height for five of the six tree species, and compost increased basal area and stem volume of all species. Species-specific responses, however, highlighted the difficulty of achieving rapid growth with limited mortality. Pioneer species had the highest growth in stem volume over 3 years (up to 3,500%), but also the highest mortality (up to 40%). Mid-successional species had lower mortality (<16%), but also the slowest growth in volume (approximately 500% in volume). Our results suggest that there will be trade-offs between optimizing tree growth versus survival when implementing urban tree planting initiatives.

green roofs

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Everybody kind of likes the idea of green roofs, but water professionals are not always 100% confident we understand them well enough to promise they will meet water quality and flooding regulations. But the studies are gradually trickling in. Here is a new one from Ecological Engineering:

Increasing recognition is being given to the adoption of green roofs in urban areas to enhance the local ecosystem. Green roofs may bring several benefits to urban areas including flood mitigation. However, empirical evidence from full-scale roofs, especially those that have been operational for more than several years is limited. This study investigates the hydrologic performance of a full-scale extensive green roof in Leeds, UK. Monitoring of the green roof took place over a 20 month period (between 30th June 2012 and 9th February 2014). The results indicate that the green roof can effectively retain and detain rainfall from the precipitation events included in the analysis. Retention was found to correspond significantly with rainfall depth, duration, intensity and prior dry weather period. Significant differences in retention values between the summer and winter seasons were also noted. Regression analysis failed to provide an accurate model to predict green roof retention as demonstrated by a validation exercise. Further monitoring of the green roof may reveal stronger relationships between rainfall characteristics and green roof retention.

Beyond questions on performance, there is a kind of chicken and egg problem where they are not used much (in the U.S., at least) because they are expensive and they are expensive because they are not used much. That is true of many emerging technologies. Of course, this “emerging” technology has been used in Europe for centuries, not to mention it is also popular with hobbits.