Anthromes v1

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Anthropogenic BiomesAnthropogenic BiomesA 21A 21stst century framework for ecology & the earth sciences century framework for ecology & the earth sciences

Erle C. Ellis

Navin Ramankutty

Department of Geography & Environmental SystemsUniversity of Maryland, Baltimore County, Baltimore, MD 21250

Department of Geography & Earth System Science Program

McGill University, Montreal, QC, H3A 2K6, Canada

Humans now shape ecological pattern and process across most of the terrestrial biosphere.

“Nature” is embedded within human systems.

Ecology needs to move beyond human footprints, impacts & domination.

Anthropogenic Biomes

• Why care about Biomes?

• Why do we need Anthropogenic Biomes?– A missing persons detective story

• How to identify & map the biomes– An empirical approach

• Anthropogenic Biomes of the World

• The way forward….– A new model for ecological research & education

Overview

On Biomes…• Biomes describe global patterns of species

composition and ecological processes– Basic units in the ecological hierarchy…

• Identified as a function of Climate, moderated

by Altitude (conventionally)

• Basic units for global ecosystem models– IGBP (17 classes; International Geosphere-Biosphere Programme)

• Core units in ecoregion analysis of biodiversity– Olson “global 200” (16 biomes, 200 ecoregions)

Why Anthropogenic Biomes?• Humans control biodiversity & ecosystem processes as

much as climate.

• Global biome maps are not realistic.– Much of biome area does not even exist (potential vegetation).– At most includes urban & agriculture (& agriculture+tree mosaic).

• Conventional, climate-based biomes are not static anyway:– Anthropogenic climate change is altering biome location &

composition.

• Biomes derived from global patterns of human interaction with landscapes may be a stronger model of global ecological patterns & processes.

Grazing

Agriculture

Urbanization

Deforestation

Habitat Fragmentation

etc…

Conventional Biomesecosystem processes are a function of macroclimate (latitude, altitude, circulation)

Ecosystem processes = f(C)

C = Climate (precipitation & temperature)

A Working Hypothesis:ecosystem processes in anthropogenic

biomes are primarily a function of human populations and their ecosystem interactions (land use)

Ecosystem processes = f(P,T) (in anthropogenic biomes)

P = Population density

T = Land use (how land & resources are used)

Anthropogenic Biomes

Anthropogenic Biomes of the WorldUrban & dense settlements

11 Urban 12 Dense settlements

Villages

21 Rice villages 22 Irrigated villages 23 Cropped & pastoral villages 24 Pastoral villages 25 Rainfed villages 26 Rainfed mosaic villages

*Mosaic: >25% tree cover mixed with > 25% pasture and/or cropland

Croplands 31 Residential irrigated cropland

32 Residential rainfed mosaic

33 Populated irrigated cropland

34 Populated rainfed cropland 35 Remote croplands

Rangelands 41 Residential rangelands

42 Populated rangelands

43 Remote rangelands

Wildlands 61 Wild forests

62 Sparse trees

63 Barren

Forested 51 Populated forests

52 Remote forests

*

Ellis & Ramankutty, in press

CroplandsAtlas Mountains, Morocco

WildlandsAlaska, USA

Credit: © BigFoto. < http://www.bigfoto.com/sites/galery/nature1/natur015.jpg >

Populated ForestKoh Samai, Thailand

Credit: © Yenit Company Ltd. <http://www.kohsamui.org/seaview.jpg>

CroplandsAtlas Mountains, Morocco

Remote RangelandsSouth Dakota, USA

Credit: © Alexander Smart. <http://ars.sdstate.edu/faculty/smarta/Range415/Image035.jpg>

Populated RangelandsAtlas Mountains, Morocco

Remote CroplandsColombia Basin, Washington, USA

Credit: © GWMA <http://www.gwma.org/images/CroplandAdjusted.jpg>

Croplands - Residential Rainfed MosaicNormandy, France

Credit: © JH.Bernard. <http://pagesperso-orange.fr/rmc14/images/IMAGES-RMC/RMC-6.JPG>

Anthropogenic Biomes of the World

Rice villages Irrigated villages Cropped & pastoral villages

Pastoral villages Rainfed villages Rainfed mosaic villages

Ellis & Ramankutty, in press

Village Biomes

Villages Jintang County, Sichuan Province, China

Rice VillagesDanyang County, Jiangsu Province, China

UrbanManhattan, New York, USA Credit: © Josh

<http://picasaweb.google.com/jiltdotorg/NewYorkCity/photo#5129550626737389474>

UrbanBaltimore County, Maryland, USA

Anthropogenic Biomes of the WorldUrban & dense settlements

11 Urban 12 Dense settlements

Villages

21 Rice villages 22 Irrigated villages 23 Cropped & pastoral villages 24 Pastoral villages 25 Rainfed villages 26 Rainfed mosaic villages

*Mosaic: >25% tree cover mixed with > 25% pasture and/or cropland

Croplands 31 Residential irrigated cropland

32 Residential rainfed mosaic

33 Populated irrigated cropland

34 Populated rainfed cropland 35 Remote croplands

Rangelands 41 Residential rangelands

42 Populated rangelands

43 Remote rangelands

Wildlands 61 Wild forests

62 Sparse trees

63 Barren

Forested 51 Populated forests

52 Remote forests

*

Ellis & Ramankutty, in press

Anthropogenic biomes

A new framework for ecologyA new framework for ecology

• Only 22% of land and 11% of NPP are wild

• Nature is now embedded within human systems– It is no longer possible to conserve nature by avoiding

human interactions

• Human interactions with the biosphere go far beyond a single dimension of impact or domination.

• Beyond the “urban + agriculture + wild” model– Forests, rangelands & croplands include people!– A wide range of population interactions.

Wildlands Forested Rangelands Croplands Villages Dense settlements

builtup

ornamentalpastureforestry

Population density

Biodiversity

Land use

Land cover baretrees

native

NPP

Carbon emissions

Reactive Nitrogen

+-

irrigated

Anthropogenic Biomes: Conceptual Model

WildlandsUrban& denseForestedRangelands VillagesCroplands

Ellis & Ramankutty, in press

Anthropogenic Biomes

Results

Anthropogenic Biomes are Mosaics– Anthropogenic landscapes are heterogeneous

mixtures of different land use and land cover classes.

– Urban areas are embedded in agricultural areas.

– Trees mixed with croplands and housing.– Managed vegetation is mixed with semi-natural

vegetation (e.g. croplands in rangelands and forests).

– Hillslopes & mountains are often islands of semi-natural vegetation

Villages Pohkara, Nepal

A better story…

“Human systems, with natural ecosystems embedded within them”.

We own the biosphere: we have altered it irreversibly. Now we control its future.

The old biosphere story… “Natural ecosystems with humans disturbing them”.

Anthropogenic biomes A new framework for educationA new framework for education

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