Tag Archives: urban ecology

March 2015 in Review

Better late than never – here’s my month in review post.

Negative stories:

  • The drought in California and the U.S. Southwest is the worst ever, including one that wiped out an earlier civilization in the same spot. At least it is being taken seriously and some policies are being put in place. Meanwhile Sao Paulo, Brazil is emerging as a cautionary tale of what happens when the political and professional leadership in a major urban area fail to take drought seriously. Some people are predicting that water shortages could spark serious social unrest in developing countries.
  • More evidence is emerging that published science skeptical of the mainstream climate consensus may have been influenced by fossil fuel industry propaganda, reminiscent of tobacco industry propaganda of the past. (By the way, tobacco industry propaganda is not a thing of the past – the industry is still up to its old tricks in developing countries that don’t stop it.)
  • El Nino has returned. Some are suggesting this is one mechanism whereby heat that has been absorbed by the ocean in recent decades could be re-released to the atmosphere. I don’t know enough to say whether this is a mainstream opinion or not.
  • Homework appears to be useless.
  • A Wall Street Journal op-ed predicts the imminent collapse of the Chinese government.
  • Farm animals, particularly pigs, are being given huge doses of antibiotics in developing countries. Beyond the risk of antibiotic resistance, it is a sign of the increasing intensification and industrialization of agriculture that is necessary as demand continues to rise.

Positive stories:

  • The concept of critical natural capital bridges the gap between strong and weak sustainability.
  • If we want to design ecosystems or just do some wildlife-friendly gardening, there is plenty of information on plants, butterflies, and pollinators out there. There is also an emerging literature on spatial habitat fragmentation and how it can be purposely designed and controlled for maximum benefit.
  • Innovation in synthetic drugs is quickly outpacing the ability of regulatory agencies to adapt. (I struggled whether to put this in the negative or positive column. Drugs certainly cause suffering and social problems. But that is true of legal tobacco and alcohol, and prescription drugs, as well as illegal drugs. The policy frameworks countries have used to deal with illegal drugs in the past half century or so, most conspicuously the U.S. “war” on drugs, have led to more harm than good, and it is a good thing that governments are starting to acknowledge this and consider new policies for the changing times.)
  • Deutsche Bank has joined the chorus predicting the coming dominance of solar power over fossil fuels.
  • There are more Uber cars than traditional taxis operating in New York City.
  • Global maternal mortality is down 40% since 1995.
  • “Germ-line engineering is much further along than anyone imagined.” This means basically editing the DNA of egg and sperm cells at will. I put this in the positive column because it can mean huge health advances. Obviously there are risks and ethical concerns too.
  • Somebody has invented an automated indoor compost bin that finicky urbanites might actually consider using.

urban tree canopy targets

This open article in PLOS ONE mentions tree canopy targets in several cities.

Increasing UTC [urban tree canopy] has become a widespread goal, often incorporated into municipal sustainability plans. It has been proposed as a way to mitigate impacts from human-dominated systems on the immediate (e.g. shade and cooling) and global (e.g. carbon capture) environment. Sacramento Tree Foundation has pledged to plant five million trees by the year 2025, an effort that would double the region’s tree canopy cover. Philadelphia has established a goal of increasing tree canopy cover to 30% by the year 2025 (www.phila.gov/green/trees). New York City, Baltimore, and Los Angeles have also announced extensive tree planting initiatives (www.milliontreesnyc.org, www.baltimorecity.gov, www.milliontreesla.org). In addition to regional efforts, there are national and global efforts to bring more awareness to the benefits of UTC cover (Urban Environmental Accord 2005, www.sfenvironment.org/downloads/library/​accords.pdf; http://www.plant-for-the-planet-billiont​reecampaign.org/Partners/VariousPartners​/TreePlanting.aspx). One of the implications of embedding tree canopy goals in sustainability plans is that environmental justice is frequently included as an objective of the plans, and sometimes explicitly linked to UTC. For example, Philadelphia’s 2009 GreenWorks Plan includes goals of increasing tree canopy cover in all neighborhoods highlighting the desire for the equitable distribution of UTC cover (www.phila.gov/green/greenworks/2009-gree​nworks-report.html).

Incidentally, I lived on a beautiful tree-lined block in Philadelphia until a year ago, when the city cut them all down to replace a major sewer line. I suppose it couldn’t be helped, and they are promising to replant.

Here are a bunch of other articles I’ve stumbled across lately on urban tree benefits:

The last is slightly negative. There are people who don’t like trees. Most of their beliefs are erroneous, but some are based on nuggets of fact. Some species of trees will invade sewer lines, particularly if they are starved of water and nutrients because they are under sealed pavement. And trees do kill a small, but nonzero, number of people each year. I believe the tree haters are a tiny but highly vocal minority. It’s not worth spending any effort trying to reason with them. The best thing to do is put a tree everywhere but in front of their house. Maybe they will see how nice it is and eventually come around. If they don’t, well, you still have more trees than you had before.

designing fragmented ecosystems

This article in Trends in Ecology and Evolution is about purposely controlling spatial fragmentation in ecosystems in order to maximize ecosystem services. If I understand correctly, their hypothesis seems to be that a system that is fragmented in a carefully designed way could provide more ecosystem services than an unfragmented system.

Landscape structure and fragmentation have important effects on ecosystem services, with a common assumption being that fragmentation reduces service provision. This is based on fragmentation’s expected effects on ecosystem service supply, but ignores how fragmentation influences the flow of services to people. Here we develop a new conceptual framework that explicitly considers the links between landscape fragmentation, the supply of services, and the flow of services to people. We argue that fragmentation’s effects on ecosystem service flow can be positive or negative, and use our framework to construct testable hypotheses about the effects of fragmentation on final ecosystem service provision. Empirical efforts to apply and test this framework are critical to improving landscape management for multiple ecosystem services.

This idea is important to the idea that we could hypothetically design a civilization that is not only less bad than the one we have now, but one that is actually good for the planet and people.

birds, bees, bugs, plants

On the green infrastructure front, there are lots of resources out there on what plants support what kinds of wildlife.

“Bugs” have a PR problem as a group, but they have their charismatic members – bees, butterflies, and dragonflies to name a few. If you support these, you will probably support others by accident. There is plenty of information out there, for example:

The Xerces Society for Invertebrate Conservation has a ton of free publications on plants, pollinators, and design; including bee-friendly plant lists for all regions of the United States and several other countries.

The Lady Bird Johnson Wildflower Center has a ton of free native plant information, including recommended mixes to attract various types of wildlife in all U.S. states and Canadian provinces.

Finally, the Natural Resources Conservation Service (part of the U.S. Department of Agriculture) has free fact sheets on about a thousand plants.

A lot of good can be done for wildlife and humanity on small scraps of land, and even more good could be done if we gave serious thought to how all those scraps of land fit together and connect to larger parks and preserves. So let’s get out and plant something this spring, even if it’s small. Or if you have a scrap of land but you don’t feel like planting anything, find a frustrated armchair gardener who doesn’t have their own scrap and let them plant something on yours.

November 2014 in Review

At the end of October, my Hope for the Future Index stood at -2.  I’ll give November posts a score from -3 to +3 based on how negative or positive they are.

Negative trends and predictions (-6):

  • There is mounting evidence that the world economy is slowing, financial corporations are still engaged in all sorts of dirty tricks, and overall investment may be dropping. Financial authorities are trying to respond through financial means, but the connections are not being made to the right kinds of investments in infrastructure, skills, and protection of natural capital that would set the stage for long-term sustainable growth in the future. (-2)
  • Public apathy over climate change in the U.S. may have been manufactured by a cynical, immoral corporate disinformation campaign over climate change taken right out of the tobacco companies’ playbook. It’s true that the tobacco companies ultimately were called to account, but not until millions of lives were lost. Will it be billions this time? (-2)
  • Glenn Beck has gone even further off his rocker, producing a video suggesting the U.N. is going to ration food and burn old people alive while playing vaguely middle eastern music. One negative point because some people out there might not laugh. (-1)
  • The new IPCC report predicts generally negative effects of climate change on crops and fisheries. The good news is it doesn’t seem to predict catastrophic collapse, but we need to remember that the food supply needs to grow substantially in the coming decades, not just hold steady, so any headwinds making that more difficult are potentially threatening. (-1)

Positive trends and predictions (+6):

  • A lot is known about how to grow healthy trees in the most urbanized environments. But only a few cities really take advantage of this readily available knowledge. (+0)
  • As manufacturing becomes increasingly high-tech, automation vs. employment is emerging as a big theme for the future. The balance may swing back and forth over time, but in the long term I think automation has to win. New wealth will be created, but the question is how broadly it will be shared. The question is not just an economic one – it depends on the kind of social and political systems people will live under in various places. This might be why the field of economics was originally called “political economy”. So I’m putting this in the positive column but giving it no points because the jury is out. (+0)
  • Google is working on nanobots that can swim around in your blood and give an early diagnosis of cancer and other diseases. (+1)
  • Economic slowing is probably the main reason why oil prices are way down. Increased supply capacity from the U.S. also probably plays a role, although there are dissenting voices how long that is going to last. I find it hard to say whether cheaper oil is good or bad. I tend to think it is just meaningless noise on the longer time scale, but you won’t hear me complain if it brings down the price of transportation and groceries for a year or two. (+0)
  • Millennials aren’t buying cars in large numbers. I don’t believe for a second that this means they are less materialistic than past generations, but I think a shift in consumption from cars to almost anything else is a net gain for sustainability. (+2)
  • I discovered the FRAGSTATS package for comprehensive spatial analysis of ecosystems and habitats. This gives us quantitative tools to design green webs that work well for both people and wildlife. Bringing land back into our economic framework in an explicit way might also help. (+1)
  • “Perennial polyculture” gardens may be able to provide food year round on small urban footprints in temperate climates. (+1)
  • A vision for smart, sustainable infrastructure involves walkable communities, closing water and material loops, and using energy wisely. Pretty much the same points I made in my book, which I don’t actively promote on this site;) (+1)

Hope for the Future Index (end of October 2014): -2

change during November 2014: -6 + 6 = 0

Hope for the Future Index (end of November 2014): -2 + 0 = -2

more trees!

This article in Landscape and Urban Planning is all about street trees. You would think this topic would have been exhausted, that is the technology would have been perfected, by now. And it has, in a few places. I am convinced it is not that leading edge knowledge about trees needs to be advanced all that much, but most cities are completely ignorant of what the best practices are. People in charge don’t know what they don’t know and have zero interest in finding out.

Street trees are an integral element of urban life. They provide a vast range of benefits in residential and commercial precincts, and they support healthy communities by providing environmental, economic and social benefits. However, increasing areas of impermeable surface can increase the stresses placed upon urban ecosystems and urban forests. These stresses often lead tree roots to proliferate in sites that provide more-favourable conditions for growth, but where they cause infrastructure damage and pavement uplift. This damage is costly and a variety of preventative measures has been tested to sustain tree health and reduce pavement damage. This review explores a wide range of literature spanning 30 years that demonstrates the benefits provided by street trees, the perceptions of street trees conveyed by urban residents, the costs of pavement damage by tree roots, and some tried and tested measures for preventing pavement damage and improving tree growth.

green web

From a blog called Better Institutions, I like this concept of a “green web”, which combines a more traditional green belt outside the city with a network of green spaces and corridors inside the city. This is the real green infrastructure vision – a system that connects patches and larger habitats and brings people, plants, and animals together and allows them to move around in a safe and low stress way. This post isn’t about that though, it’s about urban planning – green infrastructure is potentially one of the key intersection points of water, energy, transportation, air, food, climate, ecology, and urban planning.

Source: http://www.betterinstitutions.com/2014/11/green-webs-connecting-not-containing.html

Source: http://www.betterinstitutions.com/2014/11/green-webs-connecting-not-containing.html

habitat fragmentation and connectivity

Did you ever wonder how to quantitatively analyze the quality, shape, and degree of connectivity of natural habitats? Well, there’s an open source app for that, called FRAGSTATS, and good documentation that describes the theory behind it. To summarize, it looks at area and edge, shape, core area, contrast, aggregation, and diversity. Here are just a few quotes describing some of the metrics.

“Core area is defined as the area within a patch beyond some specified depth-of-edge influence (i.e., edge distance) or buffer width.”

“Contrast refers to the magnitude of difference between adjacent patch types with respect to one or more ecological attributes at a given scale that are relevant to the organism or process under consideration.”

“Aggregation refers to the tendency of patch types to be spatially aggregated; that is,
to occur in large, aggregated or “contagious” distributions.”

“FRAGSTATS computes 3 diversity indices. These diversity measures are influenced by 2 components- richness and evenness. Richness refers to the number of patch types present; evenness refers to the distribution of area among different types.”

self-driving cars and urban form

Next City has a couple good articles about what self-driving cars may mean for land use and urban form.

How will roadways, sidewalks, intersections, signage, traffic signals, and the relationship between buildings, roadways, pedestrians, cyclists, and vehicles change?

The answer to that question is in picture form, so you have to click on the link to see it. The second article explains it in words:

There is much to recommend in this imagined world of cheap, ubiquitous drone taxis. This is a world where senior citizens, the disabled, young people and the inebriated can enjoy safer mobility and be freed from the enormous costs of owning and insuring a car. It’s also a world wherein parked cars have a smaller footprint. In 2010, researchers at the University of California, Berkley released a study on the country’s parking infrastructure. While conceding that assessments of the number of parking paces have varied significantly, they cited a series of estimates, from which we can draw a reasonable range. Following this data, current parking codes have made it so there are between three and eight parking spaces for each of the 250 million cars in America. Think about it this way: If the number of personal cars dropped and parking provisions were loosened, as many as 675 million parking spaces, particularly those in urban cores, could be turned into something else — housing, parks or a million other uses more desirable than street-deadening parking lots.

“If you could push all the land currently devoted to parking in Manhattan and Boston and other big cities 10 minutes outside the city limits,” says Anthony Townsend, author of Smart Cities, “you’re potentially talking about trillions of dollars worth of real estate that could be developed, and tens of millions of new city-dwellers who could be accommodated.”

Well, sure we can turn some of it into homes and businesses. But let’s turn some of it into parks and habitat and even farms too.

green infrastructure reminder

The American Society of Landscape Architects reminds us that green infrastructure is more than what we used to call stormwater management practices. It’s a network of designed and natural ecosystems linked together to perform critical functions cheaper and better than purely manmade systems could:

Green infrastructure includes park systems, urban forests, wildlife habitat and corridors, and green roofs and green walls. These infrastructure systems protect communities against flooding or excessive heat, or help to improve air and water quality, which underpin human and environmental health…

Here are just some of the many benefits that these systems provide all at once: green infrastructure absorbs and sequesters atmospheric carbon dioxide (C02); filters air and water pollutants; stabilizes soil to prevent or reduce erosion; provides wildlife habitat; decreases solar heat gain; lowers the public cost of stormwater management infrastructure and provides flood control; and reduces energy usage through passive heating and cooling. In contrast, grey infrastructure usually provides just a single benefit.

“All at once” and “single benefit” are key phrases. You have entities like wastewater authorities, transportation authorities, parks and wildlife agencies that are each trying to maximize the single benefit they have been tasked within the limited budget each has given. Each is trying to be efficient, but together they are inefficient, redundant, and even working at cross purposes. There is nothing responsible or ethical about sitting inside your bubble making “cost-effective” decisions that ignore everything happening outside your bubble.

This article drills down to a fantastic wealth of references that we should all take a year off and read.

(By the way, this article also contains some questionable numbers about at least one program I happen to be familiar with. But never mind, the concepts are right even if the numbers are questionable.)