woensdag 26 december 2012

Pao Chao's cryptoforest

In about the year 459 Pao Chao wrote the "Wu-ch'eng fu", "rhapsody on a ruined city". The city is Kuang-Ling, modern day Yangchow, portrayed after its sacking. First it describes the city in its full splendour, then, after its fall ("divided like a melon, shared like beans") we are described scenes of the cryptoforested town. The Fu ends with the melancholy touch the western reader expect from Chinese poetry. The bit that interest me (coming from this PDF) is the portrayal of the city after nature has taken over. I think of this as a condensed version of Jefferies first chapter of After London.
Wet moss clings to the wells,
Wild vines entangle the paths.
The halls are arrayed with vipers and venomous beetles;
By the stairways deer and flying squirrels contend.
Wood sprites and mountain demons,
40 Field rats and wall foxes,
Howl in the wind, shriek in the rain,
Appear at dusk, flee at dawn.
Hungry hawks sharpen their beaks;
Winter kites hoot at young birds.
45 Crouching leopards, lurking tigers,
Suckle blood, sup on flesh.
Fallen thickets block the road;
Dark and desolate is the ancient highway.
White poplars early shed their leaves;
Wild grasses prematurely wither.
Bitter and biting is the frosty air;
Raging and roaring is the mighty wind.
A lone tumbleweed rolls by itself;
Blown sand flies of its own accord.
Dense bushes darkly stretch without end;
Thick copses wildly join one to another.
The surrounding moat already had been levelled;
The lofty turrets too have fallen.
Looking straight ahead for a thousand leagues and beyond,
All one sees is yellow dust rising.
There is another translation by Chen and Bullock that I find more to my taste because it names species and seems more ecological precise.
Duckweed flourishes in the wells
And brambles block the road.
Skunks and snakes dwell on sacred altars
While muskdeer and squirrels quarrel on marble steps.
In rain and wind,
Wood elves, mountain ghosts,
Wild rats and foxes
   Yawp and scream from dusk to dawn
Hungry hawks clash their beaks 
As cold owls frighten the chicks in their nests.
Tigers and leopards hide and wait
   for a draught of blood
   and a feast of flesh
Fallen tree-trunks lie lifelessly across
Those once busy highways.
Aspens have long ceased to rustle 
And grass dies yellow
In this harsh frosty air
Which grows into a cruelly cold wind.
A solitary reed shakes and twists,
And grains of sand, like startled birds,
   are looking for a safe place to settle.
Bushes and creepers, confused and tangled,
   seem to know no boundaries.
They pull down walls
And fill up moats.
And beyond a thousand miles
Only brown dust flies.

maandag 17 december 2012

Novel tropical forests -> cryptoforestry

Ariel Lugo was one of the first to notice that second growth tropical forests invaded by exotic species were at least as efficient biodiverse as pristine forests. His 2009 paper 'The Emerging Era of Novel Tropical Forests' is only 3 pages but foundational. Here he describes the process from abandoned plantation to forest.
(1) The dominant tree species in the forests of Puerto Rico were mostly introduced species used by people for a variety of reasons.

(2) A diverse cohort of native tree species develops underneath the canopy of introduced species.

(3) Abandoned plantations of introduced species behaved like native forests and allowed the establishment of a rich understory of native species, which then mixed with the introduced species to form a different forest type than originally present.

(4) Experimental plantings of introduced species overcame arrested succession and native forest species reestablished below their canopy.

(5) Introduced tree species had the capacity to invade degraded lands while native pioneer species could not.

(6) Introduced tree species gained importance in island forests between 1982 and 2003.

(7) Introduced species were not randomly distributed on the landscape, but reflected past land uses, bioclimate, and substrate.

(8) Emerging forests had higher tree species richness than those that were native, and functioned as did native forests, but at different rates.
The entire paper is quotable but here is the conclusion:
Novel environmental conditions created by human activity favor the remixing of species and formation of novel forests. I expect novel forests to behave ecologically as native forests do, i.e., protect soil, cycle nutrients, support wildlife, store carbon, and maintaining watershed functions. Moreover, novel forests mitigate species extinctions as they, like secondary forests, are in successional paths to maturity and species accumulation. Nature’s response to the Homogeocene cannot continue to be ignored or remain undetected by ecologists. The dawn of the age of tropical novel forests is upon us and must not be ignored. 

vrijdag 14 december 2012

Biodiversity in the Anthropocene

Following up on some links from an earlier post the following papers by Erle Ellis & various colleagues came up: 

1- Putting people in the map: anthropogenic biomes of the world (2008, PDF)

2- Anthropogenic transformation of the biomes, 1700 to 2000 (2010, PDF)

3- Anthropogenic transformation of the terrestrial biosphere (2011, PDF)

4- All Is Not Loss: Plant Biodiversity in the Anthropocene (2012, read this for a better understanding)
That's is a lot to take in. On one level the work is quantifying (with a lot of maps) "anthropogenic transformation of the terrestrial biosphere". On another level it uses the data to make statements on the need for new conceptual categories of land use.
Between 1700 and 2000, the terrestrial biosphere made the critical transition from mostly wild to mostly anthropogenic, passing the 50% mark early in the 20th century. At present, and ever more in the future, the form and process of terrestrial ecosystems in most biomes will be predominantly anthropogenic, the product of land use and other direct human interactions with ecosystems. Ecological research and conservation efforts in all but a few biomes would benefit from a primary focus on the novel remnant, recovering and managed ecosystems embedded within used lands.
But it is not all bad news:
Anthropogenic global changes in biodiversity are generally portrayed in terms of massive native species losses or invasions caused by recent human disturbance. Yet these biodiversity changes and others caused directly by human populations and their use of land tend to co-occur as long-term biodiversity change processes in the Anthropocene. Here we explore contemporary anthropogenic global patterns in vascular plant species richness at regional landscape scales by combining spatially explicit models and estimates for native species loss together with gains in exotics caused by species invasions and the introduction of agricultural domesticates and ornamental exotic plants. The patterns thus derived confirm that while native losses are likely significant across at least half of Earth's ice-free land, model predictions indicate that plant species richness has increased overall in most regional landscapes, mostly because species invasions tend to exceed native losses. 
There is a tool:
Anthropogenic species richness (ASR) results when humans interact with native patterns of species richness. Within a given area, ASR can be quantified as the sum of native species richness (N), anthropogenic loss of native species (ASL) and anthropogenic species increase (ASI). 
And there is a philosophical point:
Anthropogenic biomes point to a necessary turnaround in ecological science and education, especially for North Americans. Beginning with the first mention of ecology in school, the biosphere has long been depicted as being composed of natural biomes, perpetuating an outdated view of the world as “natural ecosystems with humans disturbing them”. Although this model has long been challenged by ecologists, ... it remains the mainstream view. Anthropogenic biomes tell a completely different story, one of “human systems, with natural ecosystems embedded within them”. This is no minor change in the story we tell our children and each other. Yet it is necessary for sustainable management of the biosphere in the 21st century. Anthropogenic biomes clearly show the inextricable intermingling of human and natural systems almost everywhere on Earth’s terrestrial surface, demonstrating that interactions between these systems can no longer be avoided in any substantial way. Moreover, human interactions with ecosystems mediated through the atmosphere (eg climate change) are even more pervasive and are disproportionately altering the areas least impacted by humans directly (polar and arid lands).
And there are also catch phrases:
The big picture: all is change
All is not loss: sustaining biodiversity in anthromes
The anthropogenic melting pots

Anthropogenic succession: thinning globally, enriching locally

Ecologists go home!

donderdag 13 december 2012

Globalization creates forests [in some places]

Quoting from an interview between the Yale environmental website e360 and Susanna Hecht on the positive effect globalization has on the regrowth of forests in El Salvador:
With globalization and structural adjustment programs, things like corn and other basic staples were coming in at import prices that were below the cost of their production in El Salvador. That meant if you were going to sell your corn, you would be selling it at a loss. So peasant agriculture soon collapsed, allowing reforestation.

Another thing about globalization is that for niche commodities it’s quite good. Those are crops that get a premium. What it meant in the case of El Salvador is that things like cashews and coffee and artisanal products made from wood had a vigorous market compared to the crummy returns you got for corn and the milpa crops [Subsistence crops such as beans and squash.] There was a shift to higher value crops, many of them arboreal.

More than half the households receive remittances from various countries, mostly from family members in the Los Angeles area. People work at jobs here in the U.S. and send money back. If you are getting remittances, you live a lot better — it basically doubles your income. Instead of having to produce corn with low yields on, say, steep slopes, you could buy the corn for the tortillas and not have to go into these forest areas. The result was a lot of land abandonment. The land was allowed to go into successional activities or forest-based economies rather than being used for producing basically corn.
The global market is against agriculture and the farmers themselves receive so much money from relatives abroad that they can retire from farming anyway! This is happening in Europe as well as noted earlier. But a secondary forest is not the same as a primal forest and lots of people are worried that Hecht's work in the wrong hands can give a rational for the deforestation of old growth forests. Earlier we quoted David Quammen warning that the invasion of weedy species and the decline of local biodiversity creates unwanted international uniformity. Hecht responds to this in a way that with a bit of effort could still be interpreted as dismissing concerns over deforestation be positively addressing the biodiversity of second growth forests. I wonder if the second growth forests of El Salvador can be understood as novel ecosystems
I am always surprised how controversial this is. I think it’s partly because some conservationists don’t count secondary forest as real forest. They see forests as ahistorical and apolitical, and the forests just aren’t. It was pounded into people in Bio 101 that human interaction with forests is destructive. But there has been extensive human influence even in places like the Amazon. What my work there taught me is that these places weren’t empty, and that if you only look at the ecological side, you don’t see the social side of forests. The conservationists really don’t like this.

What helped me to see forests in degraded areas was being around people messing in the forest. So I was primed to see the El Salvador forests and not to disparage them. To me there is almost no primary forest; it’s all secondary forests. All landscapes will have to be working landscapes. If we have lots of people with forests, we should be thrilled. And we should be really thrilled when the forest comes back because we have a narrative that it doesn’t come back.

There has been a recognition that inhabited environments can have major conservation value. Even though the reforested areas are fragmented, they are quite diverse in terms of landscape. They end up actually having a rather interesting impact at regional levels — they scale up rather better than one might imagine. Even those hedgerows can provide something like 40 to 50 percent of the biodiversity that you get in a riparian system in El Salvador. And hedgerows, land demarcations, woodlots, gardens and domestic forests of various kinds all end up supporting biodiversity in ways that are kind of surprising. For instance, the bird diversity of El Salvador is about equal to that of Belize, which has a fraction of the population and far less fragmented forests.
The image comes from Hecht's paper 'Globalization and Forest Resurgence: Changes in Forest Cover in El Salvador'

woensdag 12 december 2012

Aftermath: The Philosophy of the Beat Generation

"The Beat Generation, that was a vision that we had, John Clellon Holmes and I, and Allen Ginsberg in an even wilder way, in the late forties, of a generation of crazy, illuminated hipsters suddenly rising and roaming America, serious, bumming and hitchhiking everywhere, ragged, beatific, beautiful in an ugly graceful new way -- a vision gleaned from the way we had heard the word 'beat' spoken on streetcorners on Times Square and in the Village, in other cities in the downtown city night of postwar America -- beat, meaning down and out but full of intense conviction -- We'd even heard old 1910 Daddy Hipsters of the streets speak the word that way, with a melancholy sneer -- It never meant juvenile delinquents, it meant characters of a special spirituality who didn't gang up but were solitary Bartlebies staring out the dead wall window of our civilization -- the subterraneans heroes who'd finally turned from the 'freedom' machine of the West and were taking drugs, digging bop, having flashes of insight, experiencing the 'derangement of the senses,' talking strange, being poor and glad, prophesying a new style for American culture, a new style (we thought), a new incantation -- The same thing was almost going on in the postwar France of Sartre and Genet and what's more we knew about it -- But as to the actual existence of a Beat Generation, chances are it was really just an idea in our minds -- We'd stay up 24 hours drinking cup after cup of black coffee, playing record after record of Wardell Gray, Lester Young, Dexter Gordon, Willie Jackson, Lennie Tristano and all the rest, talking madly about that holy new feeling out there in the streets -- We'd write stories about some strange beatific Negro hepcat saint with goatee hitchhiking across Iowa with taped up horn bringing the secret message of blowing to other coasts, other cities, like a veritable Walter the Penniless leading an invisible First Crusade -- We had our mystic heroes and wrote, nay sung novels about them, erected long poems celebrating the new 'angels' of the American underground -- In actuality there was only a handful of real hip swinging cats and what there was vanished mightily swiftly during the Korean War when (and after) a sinister new kind of efficiency appeared in America, maybe it was the result of the universalization of Television and nothing else (the Polite Total Police Control of Dragnet's 'peace' officers) but the beat characters after 1950 vanished into jails and madhouses, or were shamed into silent conformity, the generation itself was shortlived and small in number."

Jack Kerouac (in Esquire 1958)

woensdag 5 december 2012

The weeds in my street tabulated

A bit of infographic handicraft in Microsoft Paint! Click to Enlarge. Trusting I won't add to the weeds in my street in the few weeks of 2012 that remain us I have tried to get some sense out of the plants on the list by ordering all 38 of them according to their family and place of origin. There must be mistakes here, there and everywhere but this is as far as I have got this year. Next year will start again.  

With many thanks to all people who supported the survey by suggesting plant names. It was invaluable!