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Anthropogenic Biomes A 21 st century framework for ecology & the earth sciences Erle C. Ellis Navin Ramankutty Department of Geography & Environmental.

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Presentation on theme: "Anthropogenic Biomes A 21 st century framework for ecology & the earth sciences Erle C. Ellis Navin Ramankutty Department of Geography & Environmental."— Presentation transcript:

1 Anthropogenic Biomes A 21 st century framework for ecology & the earth sciences Erle C. Ellis Navin Ramankutty Department of Geography & Environmental Systems University of Maryland, Baltimore County, Baltimore, MD 21250 Department of Geography & Earth System Science Program McGill University, Montreal, QC, H3A 2K6, Canada

2 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.

3 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

4 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; I nternational G eosphere- B iosphere P rogramme ) Core units in ecoregion analysis of biodiversity –Olson “global 200” (16 biomes, 200 ecoregions)

5 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…

6 Conventional Biomes ecosystem processes are a function of macroclimate (latitude, altitude, circulation) Ecosystem processes = f (C) C = Climate (precipitation & temperature)

7 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

8 Anthropogenic Biomes of the World *Mosaic: >25% tree cover mixed with > 25% pasture and/or cropland * Ellis & Ramankutty, in press

9 Croplands Atlas Mountains, Morocco Wildlands Alaska, USA Credit: © BigFoto.

10 Populated Forest Koh Samai, Thailand Credit: © Yenit Company Ltd.

11 Croplands Atlas Mountains, Morocco Remote Rangelands South Dakota, USA Credit: © Alexander Smart.

12 Populated Rangelands Atlas Mountains, Morocco

13 Remote Croplands Colombia Basin, Washington, USA Credit: © GWMA

14 Croplands - Residential Rainfed Mosaic Normandy, France Credit: © JH.Bernard.

15 Anthropogenic Biomes of the World Ellis & Ramankutty, in press Village Biomes

16 Villages Jintang County, Sichuan Province, China

17 Rice Villages Danyang County, Jiangsu Province, China

18 Urban Manhattan, New York, USA Credit: © Josh

19 Urban Baltimore County, Maryland, USA

20 Anthropogenic Biomes of the World *Mosaic: >25% tree cover mixed with > 25% pasture and/or cropland * Ellis & Ramankutty, in press

21 Anthropogenic biomes A 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.

22 Anthropogenic Biomes: Conceptual Model Wildlands Urban & dense ForestedRangelandsVillagesCroplands Ellis & Ramankutty, in press

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24 Human-manipulated ecosystems (including agricultural areas) now cover 37% of the land surface of the world. Although not generally regarded as a biome, we cannot ignore the ecology of these areas The crops that we grow today - from "fertile crescent" and the Horn of Africa and in the New World Tropics. Eighty percent of our food calories derive directly or indirectly from just six species of plant that were brought into cultivation in these areas 4 to 8,000 years ago: corn (Zea mays - Poaceae) wheat (Triticum aestivum - Poaceae) rice (Oryza sativa - Poaceae) white potato (Solanum tuberosum - Solanaceae) sweet potato (Ipomea batatas - Covolvulaceae) cassava. (Manihot esculentum - Euphorbiaceae) Agriculture as a biome? 24

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26 From M. Knee, OSU 26 As agriculture develops, these wild species are displaced and genetic resources are lost. Marginal land is brought into production and all too often becomes degraded under the pressure of use. Along with crop production, animals have been domesticated and the attempt to intensify their production has usually been disastrous. It is only possible in a country like the US with abundant land and natural resources at its disposal. Reflecting on the extent of habitat loss in the US, how can we expect poor countries to hold back from the exploitation of their remaining natural areas? Human beings now consume 40% of the earth's primary photosynthetic productivity and population is set to double in the next 50 years. The future of plant life and all life on the planet, including our own is bound up with our cultivation of the earth and its biomes. Agriculture has traditionally focused on a narrow range of plant species that are likely to remain the dominant food crops, whereas horticulture has maintained a plurality of edible and ornamental plants (and may have seemed something of a luxury). Agriculture is necessary to maintain the food supply. As natural areas and their genetic diversity disappear under increasing pressure from the human population, horticulture offers the only hope of preserving our genetic heritage and providing an environment that people will want to live in.

27 11/6/201527

28 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

29 Villages Pohkara, Nepal

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31 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 education


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