Blog List

Thursday 8 March 2018

Encountering the Urban Forest

Author
Lindsay Campbell

About the Writer: 
Lindsay Campbell

Lindsay K. Campbell is a research social scientist with the USDA Forest Service. Her current research explores the dynamics of urban politics, stewardship, and sustainability policymaking.

For all the critical scholarship that is written about the harnessing of volunteer labor in caring for urban trees (see, e.g., Perkins 2009), it never squared with my experience of engaging in stewardship. Following attendance at a human geography panel on ‘powerful objects’, I came to realize that my leisure practices were missing from my research accounts. I was writing myself out of the story, focusing only on the managerial logics of the state and civil society and the biophysical capacities and needs of the trees (Campbell 2014). The missing piece was the interactions of humans with trees, and what better way to explore those than through my own, first-hand accounts?
Inspired by Jones (2014) and Pearce et al. (2015) (see the reference below), I’ll share three stories of my engagements with street trees and reforestation sites to explore affective experiences between me and the trees. I believe that these vignettes offer windows into why and how we create and maintain relations of care with the urban forest.
Encounter 1: Street trees
Though I have worked for the US Forest Service in New York City since 2002, I had never taken part in street tree care. In the past, my colleagues and I used to joke that—despite working in the world of urban natural resource management—street trees made us sleepy. We felt they were too confined, like little toy soldiers, so neatly in their tree pits, standing in linear rows. We were interested in more open spaces—both physically and from a governance perspective—so we studied the conversion of lots to community gardens, the re-appropriation of public space for community memorials, and the restoration of contaminated urban waterways through civic action (Campbell 2006; Campbell and Wiesen 2009Svendsen and Campbell 2010). But street trees remain the primary focus for many of our researcher and manager colleagues: they are the “stars” of the urban forestry show. These are the sites of quantification and valuation and of carefully constructed managerial practices. My only substantive prior involvement with them was in a research project on young street tree mortality (Lu et al. 2010), but I had never interacted with a street tree as a steward.
Red Hook street tree. Photo: Lindsay Campbell
Red Hook street tree. Photo: Lindsay Campbell
This changed in the spring of 2014, when a new tree appeared in the sidewalk outside the door to my apartment, courtesy of the NYC Parks Departmentand the MillionTreesNYCcampaign. I did not request this tree via 311 (the New York City government’s service request number), nor did I know who did, but I suddenly felt excitement, ownership, and a sense of possibility. Here was my chance! To DO some of things I sat around yammering about in MillionTreesNYC Advisory Committee meetings or painstakingly studying for my dissertation. I didn’t have a yard, or a roof garden, and my prior community garden plot (in a privately owned, unlicensed site) had been overrun three times—first by mosquitoes, then by the cantankerous landowner, then by Hurricane Sandy. So I had no growing space. My partner, Ricardo, and I eagerly jumped at the chance to “adopt” this tree, writing out names on the tag attached to the trunk of this “wireless Zelkova”—so named because it was bred to perform well in the context of overhead utility wires, which few neighborhoods in New York City have, but which are prominent in my waterfront neighborhood of Red Hook, Brooklyn.
Our first step was to build a tree “guard”—essentially a frame around the 9 x 5 foot tree pit—that would both protect the tree and aesthetically demarcate our garden bed. I queried my artist friends for ideas about how to build a funky guard out of found maritime objects, signaling the waterfront connection of my neighborhood and reusing waste. But I am neither an artist nor a very good scavenger, so ultimately this involved a dreaded trip to Lowes hardware store. About $100 later, we had our lumber (FSC certified and sustainable), stakes, fasteners, and a few plants. (Some perennials, a few annuals just to get us started. From where? Who knows?). It is not lost on me that if you add up the ‘board feet’ of lumber surrounding the tree in the guard and the supportive stakes helping the young tree to get started, our little street tree’s volume of wood is dwarfed by the wood we use to protect it.
When we were outside building the guard, our downstairs neighbor came upon us with a perplexed look. She wanted to know if we had gotten permission to care for the tree. I proudly proclaimed that the tree was in the public right of way (PROW) and that the city wants us to care for trees. Ricardo silently pointed to our names on the Adopt-a-Tree tag, noting the tacit legitimacy that it gave us. I suddenly personally understood the sense of the PROW as a ‘grey area’, particularly for renters in a multi-unit building (see Rae et al. 2010). To whom did the tree “belong”? What really gave us the right to claim it? Our labor? Our capital expense? Calling ‘dibs’ on a tree tag? Once we put our meager plants in, I was shocked at how much space remained in the bed. I would have happily joined with other neighbors in planting out the garden bed a little more fully, but the rectangle did feel like a single serving size garden. The neighbor never inquired again, and the tree seemed to be “ours”.
Tree with guard and plantings. Photo: Lindsay Campbell
Tree with guard and plantings. Photo: Lindsay Campbell
As our attachment deepened, we began to anthropomorphize tree a bit. We named it (uncreatively) “Tree” and talked about it like our adoptive child. As recently cohabiting, childless partners, we were joking—but only sort of. We don’t have pets. We try to keep the houseplants alive. Tree came next. Most of the work involved lugging 10 gallon buckets of water down three flights of stairs. I kept urging Ricardo to befriend our downstairs bodega guys, to ask if we could use their sink or hose hook up, but I was too nervous to ask myself. Even though I shopped there nearly daily and said my polite hellos, the whole street corner life/Jane Jacobs/social cohesion thing is a lot harder to enact in real life than it is to just read about and coo over—especially when it involves asking a favor of someone. So, instead, we lugged the buckets up and down the stairs, trying our best to meet the recommended 20 gallons of water per week in the summer, but usually not making it, and using the degree of desiccation of our marigolds as a marker for when we really needed to water.
Eventually we experienced setbacks. As someone exited their car and knocked their car door against the tree guard, they ripped out one whole side of our guard. We dutifully repaired it. This happened again a few weeks later and then Ricardo and I were really crestfallen. But when we returned from work, someone else had repaired the guard. While we are pretty sure it was our building super who was constructing a new trash shed, we preferred to think of it as some anonymous Good Samaritan. More generally, I was worried about the structural soundness of the guard overall. Looking at the completed work, it looked strikingly like a playground balance beam and was just crying out to be walked, stood, or balanced upon. Though I never witnessed it happening at our tree, I’d see this throughout the neighborhood on other tree guard sites. Also, we had a new hipster art space just two doors down, and all the parties and openings to go with it; this led to a rise in the foot traffic and cigarette butts we encountered on the street. Most mornings I would stoop to clean the accumulated garbage out of the pit. Further, my former roommate was dog-sitting and he informed me that “Ginger just loves the new bathroom outside!” Horrified, I explained that the dog urine was bad for the tree and our little plants, and he really should curb her. Yet, when I helped out by walking Ginger one day, I couldn’t bring myself to stop her from crouching on the bit of available dirt that she scurried to—it just felt like she had to scratch her feet in the dirt, and making her crouch on the concrete didn’t respect her dog-hood. But, I still didn’t let her use our tree. So we made a sign: “Please keep tree healthy—no butts or mutts.”
The big setback came on a fall morning in 2014 when I was awoken to the sound of jack hammers. As I left for work, I opened the door to see three of my building owner’s contractors operating a bobcat, tearing out the sidewalk. The tree guard was ripped out, Tree’s dirt was splayed about, and chunks of concrete mounded on the corner. Ricardo asked the workers to replace the guard when their work on the sidewalk was done, and they assured us they would.
A few days and one angry email to my landlord later, the guard was indeed restored. We breathed a sigh of relief: Tree was safe and protected—for now.
Encounter 2: Reforestation sites
Planting Trees 
I headed out to Alley Pond Park in northeastern Queens, NY on a spring day in 2013 for my first urban afforestation planting experience. I knew Alley Pond from my work as being one of the sites that the NYC Parks Department natural resource folks were most proud of—closed canopy, tall trees, wide mulch and dirt paths—you really get the feeling of the forest in Alley Pond. But like so many of New York City’s ‘natural areas’, it is highly patchy and variable across space, criss-crossed and subdivided by a spaghetti of deep-Queens major roadways—the Cross Island Parkway, the Grand Central Parkway, and the Long Island Expressway.
IMG_5273
Alley Pond Park Trails. Photo: Sadia Butt
The corner of Alley Pond that we approached that day in which to ‘plant a forest’ was unfamiliar to me, and didn’t look much like the soaring, large canopy trees I’d seen in other sections. It was just a wide open, slightly sloping field, pockmarked with hundreds of holes and young trees at the ready. As I set to work, it felt so satisfying to fill the holes, nestling each tree comfortably in its spot, and moving on to the next, like crossing off an item in a to-do list, or fitting in a puzzle piece.
But what I noticed more than the site that day, or even interacting with the trees, were the social dynamics at work. The first thing I felt was the energy and enthusiasm of the staff. They knew how to treat us right—a quick entry sign-in, free breakfast, coffee, garden gloves, ample tools, quick demo, and off you go! Ricardo and I got into quite a rhythm. We didn’t really talk to others while we were working—there was work to do.
photo (9)
Alley Pond Afforestation site. Photo: Lindsay Campbell
We hadn’t come with a big corporate group—we lacked the matching hats or tee shirts that immediately identified those folks. But as our backs tired and we slowed down, I lifted my head up from the dirt and saw friends, co-workers, and their children. It was a great equalizer between my colleague’s seven year old son, me, and the Deputy Commissioner of the Parks Department. The suits were off, it felt familial and easy. Eating my box lunch in the sun, sitting on the ground, talking to other tree planters was probably my favorite part of the day.
IMG_1601
The author planting trees.
Stewarding Trees
As the MillionTreesNYC campaign began to wrap up in fall 2014, the Parks Department organized large-scale stewardship days along with planting days. So, I returned to (yet another section of) Alley Pond Park in Queens to see what it was like to steward a young forest. We were greeted with some granola bars, work gloves, and told to wait. A bit less scripted than the mass plantings, this was a smaller site with a few dozen people and one BIG pile of mulch. We were sent out in groups of around ten, and those of us stragglers that came without a team or group (like Ricardo and me) had to wait for a sufficient posse to be sent out. I have to say this made me feel a little orphaned. We watched patiently as four tiny girl scouts pushed a wheelbarrow that one of us could have handled. At points, there were not enough buckets for everyone to have one. Like so many volunteer experiences, the point here was not efficiency of labor; it was about inclusion, intention, fun, and engagement. Still, I wanted to feel useful.
IMG_2914
NYC Parks employee showing how to mulch a tree. Photo: Lindsay Campbell
When it was our turn to go, we got a pep talk about how “planting trees is just the beginning;” Parks workers demonstrated how to properly mulch a young tree by making a donut around it. The point of this mulch was less to enhance the soil and more to help keep out weeds and give the young native tree a fighting chance against the vines, Ailanthus, and other invasives surrounding it. They didn’t expressly instruct us to pull weeds, but pull we did. Even with the gloves, I gave myself callouses from pulling so many weeds. Ricardo wrenched his back doing battle against an Ailanthus root. While I could sit in a conference room and debate novel ecosystems and the language of native versus invasive, when I was here—in the field—I was pulling out those invasives, for sure. My colleague, who has much stronger ecology chops than I do, couldn’t help but comment on the possible futility of the effort—all while she, too, was pulling weeds. Those Ailanthus trees would return. Maybe it was futile, but it was fun. It felt like we were doing good. But looking around the site, she noted the proximity to a wetland, and wondered whether these young oaks even ‘belonged’ in this site. Perhaps other species of grasses and bushes would have been more appropriate?
IMG_2917
Ricardo stewarding trees. Photo: Lindsay Campbell
Once we cleaned out vines and weeds, we noted how far away the site was from the desired goal of ‘closing the canopy’. Talking with one of the Park workers, he mentioned that he thought it was one of the forest research sites, which meant that managers weren’t going in and planting additional trees, but were letting the forest competition play out—while still holding stewardship events like ours. I realized that—if he was right—I was the embodiment of a variable in the experimental forest plot treatments (mulch / no mulch) that some of my ecology colleagues were involved in running. We would have to wait decades for this experiment to unfold before we knew the outcomes of different treatments. Did it make sense to plant a forest in this site? Would it even work? The managers and stewards working on the site have to take these future outcomes as uncertain—as leaps of faith.
IMG_2912
Young forest at Alley Pond Park. Photo: Lindsay Campbell
As before, the day concluded with box lunches, which we consumed while sitting on our overturned mulch buckets. Surrounded by a few dozen other New Yorkers, we chatted about the challenges of growing a forest in the city. And we went home that afternoon to plant fall bulbs around our own beloved Tree.
Concluding thoughts
By placing myself more centrally in these accounts, I present a ‘situated science’ approach to the subject of the urban forest (see Haraway 1991). Paying attention to social context, emotional ties, and affective registers tells a different tale than a remotely sensed, infrared image of urban tree canopy or the quantified accounting of ecosystem services provided by trees. These human-tree connections that we build require different methodological tools to uncover and certainly require a different understanding of what constitutes a research account. But I believe that sharing these stories helps move us towards a fuller understanding of why we create and maintain urban forests.
My relations with urban trees are complex. They are mediated by my needs, assumptions, and values. As these relations move beyond the conceptual and intellectual realms and into the physical and embodied, some of my assumptions have begun to shift:
Taking care of street trees isn’t as easy as I thought. Barriers like access to power tools and water sources are not trivial. Still, I’m willing to overcome these obstacles slowly, imperfectly, and over time. I don’t have a green thumb, I’ll learn through trial and error over the seasons as the tree and I grow together. Over the past year or so, the 45 square foot patch of land where my street tree is planted has come to occupy a much larger space in my mind and heart. I care for Tree, I fawn over Tree. I feel pride when I plant some new native grasses, I feel defensive when I swat off the squirrels. I feel angry when people litter or break the guard. I feel worried about whether Tree will make it through this brutal winter, as big drifts of snow mound up over the guard. I never could have predicted how much time and effort I would expend caring for Tree. But, I am also surprised by all that I have gotten in return from developing a real attachment to a piece of ground and caring for an organism situated within it.
On reforestation sites, I was surprised to learn that I like working hard, for free, on behalf of an effort greater than myselfI’ve come to understand why so many of the volunteer tree planters became repeat attendees, as my colleagues have shown in their work on the links between tree planting and civic engagement (Fisher et al. 20112015). Even though the MillionTreesNYC campaign wasn’t originally conceived with a community forestry ethos, these volunteer events had evolved that way. The tree became the widget to bring people together. What mattered was what surrounded those trees: all of us.
The question remains, then, how can we build bridges between these emotional experiences and our management practices? How can we scale up from individual experiences that are deep but uneven across the population (dedicated street tree stewards) or far-reaching but isolated in time and space (one-time reforestation volunteer events)? How can we cultivate attachment and stewardship but also allow attachment to inform management, decision-making, and priority-setting? What would it look like to grow a forest that is rooted in these community relations all along the way? How can we truly honor relations of care between humans and trees and set ourselves up to create more of these experiences throughout the cycle of creating and maintaining an urban forest—from site selection, to material sourcing, to installation, to maintenance, to removal and reuse?
Lindsay K. Campbell
New York
Works Cited
Campbell, Lindsay K. 2014. “Constructing New York City’s urban forest: The politics and governance of the MillionTreesNYC campaign.” in Urban Forests, Trees, and Green Space: A Political Ecology. L. Anders Sandberg, Adrina Bardekjian, and Sadia Butt, Eds. Routledge Press, pp. 242-260.
Campbell, Lindsay and Anne Wiesen, Eds. 2009Restorative Commons: Creating Health and Well-being through Urban Landscapes. General Technical Report. Newtown Square, PA: U.S. Department of Agriculture, Forest Service, Northern Research Station.
Fisher, Dana L.; Connolly, James J.; Svendsen, Erika S.; and Lindsay K. Campbell. 2011. Digging Together: Why people volunteer to help plant one million trees in New York City. Environmental Stewardship Project at the Center for Society and Environment of the University of Maryland White Paper #2. 36 p. Available online here.
Haraway, D. 1991. “Situated Knowledges: The Science Question in Feminism and the Privilege of Partial Perspective.” in Simians, Cyborgs, and Women. New York: Routledge.
Jones, Owain. 2014. “(Urban) Places of Trees: Affective Embodiment, Politics, Identity, and Materiality” in Urban Forests, Trees, and Green Space: A Political Ecology. L. Anders Sandberg, Adrina Bardekjian, and Sadia Butt, Eds. Routledge Press, pp. 111-131.
Perkins, H. A. (2009). Out from the (Green) shadow? Neoliberal hegemony through the market logic of shared urban environmental governance. Political Geography28(7), 395–405.
For further information log on website :
https://www.thenatureofcities.com/2015/03/04/encountering-the-urban-forest/

RIO — THE WORLD’S LARGEST URBAN FOREST

Author



Imagine cruising through the world’s largest urban forest and pedaling down a long coastal road that stretches out onto the horizon. Spice that up with some steep climbs to make your legs burn and top it all off with one of the world’s most iconic landmark in one ride. It almost seems impossible, well, not for some — welcome to Rio de Janeiro.
Host to the 2016 Summer Olympics, the city was quickly infected by one sport: cycling. Ever since the torch was extinguished, the number of riders in this iconic city has rapidly grown, and these cyclists have ben encouraged by the idyllic scenery.
Among these new cyclists is Ana Vitoria Magalhães, ‘Tota’. This 17 year old is the perfect example of the “carioca” way of life, all smiles and brightness. Rarely found inside, you’re most likely to come across Tota practicing her favorite sports, which include (but are not limited to) football and cycling.
“Every day people ask me where I get all my energy from,” explains the captivating Tota. “My reply is quite simple; I wake up at 6am, have my breakfast and head out for a training session. Usually I start climbing through the Mesa do Imperador and with each pedal stroke, I get more enthralled by the trees, animals and views surrounding me. This is what I love the most about Rio. When I get there, I follow the road to my favorite place, the statue of Christ the Redeemer. That monument, which is so entrenched in the nature around it, brings me a lot of peace. After that, I do another little climb to the Mirante Dona Martha, eager for the breathtaking view. When I finish my ride, the best way to refuel is to have an Açaí followed by a dip in the warm ocean. Then I can call it a day!”















With local knowledge on the best places to ride, Tota suggests exploring the many roads that traverse the dense Atlantic Tijuca Forest. With temperate year-round riding conditions, Rio is one fortunate city. Even on the coolest winter days, the mercury might drop to a mere 17˚C. During the summer it can reach 40˚C, but then, Tota gives a broad grin, “you can either cool off in the ocean or in one of the many waterfalls that flank the roads you’re cycling along.”

For further information log on website :
https://www.assos.com/shorts-stories/rio-the-world-largest-urban-forest

Routes: 50 Miles of Urban Forest and Industrial Jungle With Rich Laverty

Author

By: SJ Punderson
It was drizzling the first time I met Rich Laverty. The clouds were rumbling behind the South Street Bridge, the direction he had come from after leaving work in Ridley Park. Laverty, an engineer from Greeley Colorado, stopped mid-way through his ride home to Chestnut Hill to chat. He was about halfway into his 25 mile each-way ride. In retrospect, the weather was a good indication of the kind of cyclist Laverty is. Mild weather changes don’t seem to bother this guy.
As Laverty, 46, told me about how he ended up in northwest Philadelphia a few years ago, rain began to really pelt my phone, which was recording the conversation. I tried to tough it out, as he didn’t seem to notice.
“Weather will prevent me from riding sometimes,” he said. “I won’t ride in the snow.”
The rain had transformed into a full-blown downpour, and so we ducked inside to finish out the conversation. Laverty decided to continue his daily commute on bike when he and his wife, Kathleen, moved from Center City to Chestnut Hill. He does it less now, once or twice a week, but really looks forward to the alone time, and the exercise.
“I hate driving,” he said. “If traffic is clear, it’s a 45 minute commute, and if not, it’s longer.”
Many cyclists can understand Laverty’s aversion to sitting in car traffic. His total mileage, a whopping 50 miles, is the furthest of any of the Routes bike commuters interviewed thus far. He starts in Chestnut Hill, skirts the Wissahickon Park and hops on the paved path where Lincoln Drive meets Forbidden Drive.
From there, it’s Kelly Drive to South Street, where he exits the trail and follows Gray’s Ferry over the river, turns onto Lindbergh Ave South towards the Heinz Wildlife Refuge, where Bartram connects Lindbergh and Industrial Highway 291.
“Rich is a beast on the bike,” said Laverty’s friend, Andy Andrews. “The worse the terrain, the better he is. It doesn’t surprise me that he is one of the few that would make that commute.”
In college, Laverty started mountain biking. He was a self-described “very bad bike racer” for several years, which led him to start running. Over time, running injuries returned him to cycling.
“Riding a bike has been a part of my life ever since,” he said. “Now, I leave for work at about 5:30 a.m. and arrive by 7, shower and change.”
On his seventh birthday, a landmark celebration in the Laverty family, Rich received his first bike.
“It was the 1970s and BMX bikes were really popular,” he said. “But I didn’t get the one I wanted.”
By age nine, the young cyclist had taken on a paper route. He was delivering over 100 newspapers every day, and was able to upgrade.
“I traded up in several steps, until I had the nicest BMX bike possible.”
By the time his BMX phase came to an end, Laverty, 14, was playing sports every day, had given up the paper route and wasn’t biking. He wouldn’t get back in the saddle until college.
“I wouldn’t call it a dark period, but that was a time without bikes,” he said.
These days, Laverty is enjoying the moments he can steal on his bicycle. He rides a 14 year-old, welded steel SOMA frame in soft orange.
“There aren’t any decals on my bike because this past spring, I had it powder-coated at Bonehead Performance in Warrington,” he said. “The cost was reasonable and they know what they’re doing.”
Laverty isn’t the only person in his family that bikes. His wife Kathleen and nine year-old daughter Alison will sometimes join him for a ride on the weekends.
“I look at being on a bike as part of the package with Rich,” said Kathleen. “Exercise is just something he needs. He has always been into cycling, but when I met him he had just finished a 50 mile run and was training for a marathon.”
It’s pitch black when Laverty leaves for work on his bicycle in the mornings. He doesn’t wear headphones, says it ruins the experience. For safety he has a bright front light as good as any on a car and two red flashers on the back. Even though Laverty doesn’t make stops when he’s riding from A to B, he pays attention to the micro moments, one of his favorite parts about bike commuting.
“One morning, there was one person out rowing on the Schuylkill,” he said. “It was still dark, the moon was out, and there was a beautiful reflection. I wouldn’t have noticed that in a car.”
When tasked with which part of Laverty’s ride to join him on, I’ll admit that I went the easy route. Again, we met at Boathouse Row on a Friday afternoon. From there, I rode with him to Chestnut Hill.
Otherwise, I pedaled quickly to try and keep up with the lanky Laverty, who seemed to effortlessly glide up the hills near the Wissahickon Transfer Station. The final mile push of our ride had me gasping, as Laverty steered us up Valley Green Road near Valley Green Inn, which eventually turned into West Springfield Ave.
“This is probably the hardest part,” Laverty admitted, something he left out in all of our correspondence before the ride.
Dignity was the only thing that kept me pushing, albeit slowly, to finish out the ride.
When Laverty travels beyond Philadelphia with Kathleen and Alison, the family tends to sightsee on foot. As far as biking in unfamiliar places, he likes to feel out any of the local rules and customs before he rides.
“I’ve never been to any of the big biking cities, but Kathleen has,” he said. “I’d love to live in a place where there are more bikes than cars.”
For now, Laverty will have to settle for riding the river trail before the sun rises and heading home.
“I have an emotional attachment to my bike, to cycling in general,” he said. “I hope I can continue to do it for a very long time.”
 2,440 total views, 0 views today
For further information log on website :
http://bicyclecoalition.org/routes-50-miles-urban-forest-industrial-jungle-rich-laverty/#sthash.VbNFmJCi.dpbs

Nitrogen cycling processes and soil characteristics in an urban versus rural forest

Author
  • Carleton S. White
  • Mark J. McDonnell
Abstract

Different soils of an urban forest in New York City showed relatively low, yet similar rates of N mineralization and nitrification in laboratory potential measurements. This consistent pattern occurred even though a number of factors known to influence these processes (including overstory vegetation, soil type, and heavy metal levels) differed between the urban samples. Net N mineralization rates in forest floor and A horizon samples from a hemlock stand within the urban forest were 81% and 53% lower than respective samples from a comparable rural stand. In addition, all forest floor and A horizon samples from the urban forest were extremely hydrophobic. The low mineralization rates and hydrophobic nature of the urban samples suggested that factors associated with the ‘urban grime’ hydrocarbons may be limiting the activity of soil microbes and invertebrates. Trampling and high concentrations of heavy metals may have synergistic effects that would act to reduce net N mineralization and nitrification within the urban forest.

References

  1. Adams, S., B.R. Strain & M.S. Adams (1970) Water-repellent soils, fire, and annual plant cover in a desert scrub community of southeastern California. Ecology 51: 696–700Google Scholar
  2. Binkley, D., J. Aber & K. Nadelhoffer (1986) Nitrogen availability in some Wisconsin forests: comparisons of resin bags and on-site incubations. Biology and Fertility of Soils 2: 77–82Google Scholar
  3. Bremner, J.M. & L.A. Douglas (1971) Use of plastic films for aeration in soil incubation experiments. Soil Biology and Biochemistry 3: 289–296Google Scholar
  4. Britton, N.L. (1906) The hemlock grove on the banks of the Bronx River and what it signifies. Transactions of the Bronx Society of Arts and Sciences 1: 5–13Google Scholar
  5. Broddin, W., W. Cautreels & K. Van Cauwenberghe (1980) On the aliphatic and polyaromatic hydrocarbon levels in urban and background aerosols from Belgium and The Netherlands. Atmospheric Environment 14: 895–910Google Scholar
  6. Broughton, J.G., D.W. Fisher, Y.W. Isachsen & L.V. Richard (1966) Geology of New York: a short account. The University of New York, The State Education Department and New York State Museum and Science Service Educational Leaflet No. 20Google Scholar
  7. Bornkamm, R., J.A. Lee & M.R.D. Seaward (Eds) (1982) Urban Ecology. The Second European Ecological Symposium, Berlin, 8–12 September 1980. Blackwell Scientific Publications, London, EnglandGoogle Scholar
  8. Carlyle, J.C. & D.C. Malcolm (1986) Nitrogen availability beneath pure spruce and mixed larch + spruce stands growing on a deep peat. I. Net N mineralization measured by field and laboratory incubations. Plant and Soil 93: 95–113Google Scholar
  9. Climatography of the United States No. 20. (1985) Climatic summaries for selected sites in New York, 1951–1980. National Oceanic and Atmospheric AdministrationGoogle Scholar
  10. Cole, D.N. (1985) Recreational trampling effects on six habitat types in western Montana. USDA Forest Service Research Paper INT-350. Intermountain Research Station, Ogden, Utah, USAGoogle Scholar
  11. DeBano, L.F. (1971) The effects of hydrophobic substances on water movement in soil during infiltration. Soil Science Society of America, Proceedings 35: 340–343Google Scholar
  12. DeBano, L.F., L.D. Mann & D.A. Hamilton (1970) Translocation of hydrophobic substances into soil by burning organic litter. Soil Science Society of America, Proceedings 34: 130–133Google Scholar
  13. Doelman, P. & L. Haanstra (1984) Short-term and long-term effects of cadmium, chromium, copper, nickel, lead, and zinc on soil microbial respiration in relation to abiotic soil factors. Plant and Soil 75: 317–327Google Scholar
  14. Farmer, C.T. & T.L. Wade (1986) Relationship of ambient atmospheric hydrocarbon (C12­C32) concentrations to deposition. Water, Air and Soil Pollution 29: 439–452Google Scholar
  15. Flanagan, P.W. & K. Van Cleve (1983) Nutrient cycling in relation to decomposition and organic-matter quality in taiga ecosystems. Canadian Journal of Forest Research 13: 795–817Google Scholar
  16. Friedland, A.J., A.H. Johnson & T.G. Siccama (1986) Zinc, Cu, Ni and Cd in the forest floor in the northeastern United States. Water, Air and Soil Pollution 29: 233–243Google Scholar
  17. Gill, D. & P. Bonnett (1973) Nature in the Urban Landscape: A Study of City Ecosystems. York Press, Baltimore, Maryland, USAGoogle Scholar
  18. Giovannini, G. & S. Lucchesi (1984) Differential thermal analysis and infrared investigations on soil hydrophobic substances. Soil Science 137: 457–463Google Scholar
  19. Gleason, H.A. & A. Cronquist (1963) Manual of Vascular Plants of Northeastern United States and Adjacent Canada. D. Van Nostrand Company. New YorkGoogle Scholar
  20. Gosz, J.R. & C.S. White (1986) Seasonal and annual variation in nitrogen mineralization and nitrification along an elevational gradient in New Mexico. Biogeochemistry 2: 281–297Google Scholar
  21. Gosz, J.R., D.R. Brookins & D.I. Moore (1983) Using strontium isotope ratios to estimate inputs to ecosystems. BioScience 33: 23–30Google Scholar
  22. Graustein, W.C. & R.L. Armstrong (1983) The use of strontium-87/strontium-86 ratios to measure atmospheric transport into forested watersheds. Science 219: 289–292Google Scholar
  23. Grodzinski, W., J. Weiner & P.F. Maycock (Eds) (1984) Forest Ecosystems in Industrial Regions. Springer-Verlag, New York, New York, USAGoogle Scholar
  24. Jamison, V.C. (1946) Resistance to wetting in the surface of sandy soils under citrus trees in central Florida and its effect upon penetration and the efficiency of irrigation. Soil Science Society of America, Proceedings 11: 103–109Google Scholar
  25. Johnson, A.H., T.G. Siccama & A.J. Friedland (1982) Spatial and temporal patterns of lead accumulation in the forest floor in the northeastern United States. Journal of Environmental Quality 11: 577–580Google Scholar
  26. Klein, T.M. & M. Alexander (1986) Effects of the quality and duration of application of simulated acid precipitation on nitrogen mineralization and nitrification in a forest soil. Water, Air and Soil Pollution 28: 309–318Google Scholar
  27. Knopf, E.B. (1927) Some results of recent work in the southern Taconic area. American Journal of Science 24: 429–458Google Scholar
  28. Matsumoto, G. & T. Hanya (1980) Organic constituents in atmospheric fallout in the Tokyo area. Atmospheric Environment 14: 1409–1419Google Scholar
  29. McGhie, D.A. & A.M. Posner (1981) The effect of plant top material on the water repellence of fired sands and water repellent soils. Australian Journal of Agricultural Research 32: 609–520Google Scholar
  30. Nadelhoffer, K.J., J.D. Aber & J.M. Melillo (1983) Leaf litter production and soil organic matter dynamics along a nutrient availability gradient in southern Wisconsin (USA). Canadian Journal of Forest Research 13: 12–21Google Scholar
  31. National Academy of Sciences (1983) Acid Deposition: Atmospheric Processes in Eastern North America: A Review of Current Scientific Understanding. National Research Council, National Academy Press, Washington, D.C., USAGoogle Scholar
  32. National Academy of Sciences (1984) Acid Deposition: Processes of Lake Acidification. National Research Council, National Academy Press, Washington, D.C., USAGoogle Scholar
  33. Neuhauser, E.F., R.C. Loehr, D.L. Milligan & M.R. Malecki (1985) Toxicity of metals to the earthworm Eisenia fetida. Biology and Fertility of Soils 1: 149–152Google Scholar
  34. Numata, M. (1977) The impact of urbanization on vegetation in Japan. In: A. Miyawaki & R. Tuxen(Eds) Vegetation Science and Environmental Protection (pp. 161–171). MAruzen, Tokyo, JapanGoogle Scholar
  35. Olson, R.K. & W.A. Reiners (1983) Nitrification in subalpine balsam fir soils: tests for inhibitory factors. Soil Biology and Biochemistry 15: 413–418Google Scholar
  36. Pack, A.B. (1974) The climate of New York. In: Climates of the States. Vol. 1. Eastern States. Water Information Center, Inc., Port Washington, New York, USAGoogle Scholar
  37. Reeder, C.J. & M.F. Jurgensen (1979) Fire induced water repellency in forest soils of upper Michigan. Canadian Journal of Forest Research 9: 369–373Google Scholar
  38. Richardson, J.L. & F.D. Hale (1978) Influence of vegetation on water repellency in selected western Wisconsin, USA soils. Soil Science Society of America, Journal 42: 465–467Google Scholar
  39. Robertson, G.P. (1982) Factors regulating nitrification in primary and secondary succession. Ecology 63: 1561–1573Google Scholar
  40. Roundtree, R.A. (Ed) (1984) Ecology of the Urban Forest. Part I. Structure and Composition. Urban Ecology 8: 1–178Google Scholar
  41. Ruhling, A. & G. Tyler (1973) Heavy metal pollution and decomposition of spruce needle litter. Oikos 24: 402–416Google Scholar
  42. Savage, S.N., J.P. Martin & J. Letey (1972) Substances contributing to fire-induced water repellency in soils. Soil Science Society of America, Proceedings 36: 674–678Google Scholar
  43. Schlesinger, W.H. & W.A. Reiners (1974) Deposition of water and cations on artificial foliar collectors in fir krummholz of New England mountains. Ecology 55: 378–386Google Scholar
  44. Schuberth, C.J. (1968) The Geology of New York City and Environs. Natural History Press, New York, New York, USAGoogle Scholar
  45. Seastedt, T.R. (1984) The role of microarthropods in decomposition and mineralization processes. Annual Review in Entomology 29: 25–46Google Scholar
  46. Secor, W., L.F. Koehler, D.F. Kinsman, M.G. Cline, W.J. Moran, J.D. Ruffner, J.D. Sheetz & L.P. Kelsey (1955) Soil Survey of Dutchess County, New York. USDA Soil Conservation Service and Cornell University Agricultural Experiment Station Series 1939, No. 23Google Scholar
  47. Smeltzer, D.L.K., D.R. Bergdahl & J.R. Donnelly (1986) Forest ecosystem responses to artificially induced soil compaction. II. Selected soil microorganism populations. Canadian Journal of Forest Research 16: 870–872Google Scholar
  48. Stern, A.C., R.W. Boubel, D.B. Turner & D.L. Fox (1984) Fundamentals of Air Pollution. Academic Press, New York, New York, USAGoogle Scholar
  49. Thornes, L.A. (1974) Soil survey of the hemlock forest at the New York Botanical Garden, Bronx, New York 10458. Report prepared by the USDA Soil Conservation Service in cooperation with Cornell UniversityGoogle Scholar
  50. Tyler, G. (1975) Heavy metal pollution and mineralization of nitrogen in forest soils. Nature 255: 701–702Google Scholar
  51. Vitousek, P.M., J.R. Gosz, C.C. Grier, J.M. Melillo & W.A. Reiners (1982) A comparative analysis of potential nitrification and nitrate mobility in forest ecosystems. Ecological Monographs 52: 155–177Google Scholar
  52. Vitousek, P.M. & P.A. Matson (1985) Causes of delayed nitrate production in two Indiana forests. Forest Science 31: 122–131Google Scholar
  53. Volchok, H.L., L.E. Toonkel & M. Schonberg (1974) Trace metals — Fallout in New York City II. US Atomic Energy Commission Report HASL-281. Health and Safety Laboratory, New York, New York, USAGoogle Scholar
  54. Wade, T.L. (1983) Bulk atmospheric deposition of hydrocarbons to lower Chesapeake Bay. Atmospheric Environment 17: 2311–2320Google Scholar
  55. White, C.S. (1986) Volatile and water-soluble inhibitors of nitrogen mineralization and nitrification in a ponderosa pine ecosystem. Biology and Fertility of Soils 2: 97–104Google Scholar
  56. White, C.S. & J.R. Gosz (1987) Factors controlling nitrogen mineralization in New Mexico forest ecosystems. Biology and Fertility of Soils 5: 195–202Google Scholar

About This Article As :

Cite this article as:
White, C.S. & McDonnell, M.J. Biogeochemistry (1988) 5: 243. https://doi.org/10.1007/BF02180230
  • DOIhttps://doi.org/10.1007/BF02180230
  •  
  • Publisher NameKluwer Academic Publishers
  •  
  • Print ISSN0168-2563
  • Online ISSN1573-515X
For further details log on website:
https://link.springer.com/article/10.1007/BF02180230

Advantages and Disadvantages of Fasting for Runners

Author BY   ANDREA CESPEDES  Food is fuel, especially for serious runners who need a lot of energy. It may seem counterintuiti...