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• Human requirements

• Natural resources

• Ecosystem functions

• Ecosystem services

• Ecological footprints• Biocapacity

AgroecologyEcological understanding of farming systems

Ben-Gurion University of the Negev

4. Ecosystem services

bboeken@bgu.ac.ilhttp://www.bgu.ac.il/desert_agriculture/Agroecology/Ó BBoeken 2005-18

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Human requirementsPhysical supplies

– Air

– Water

– Space

– Food

– Fiber– Shelter

– Medicine

Quantity and quality depend on

• Dependency on natural ecosystems

• Human control of supply and production• Population density• Awareness and empowerment

Cultural needs– Pleasure– Art– Knowledge– Religion

– Nature – Biodiversity– Wildlife – Travel – Technology– Industry Other physical needs

– Safety

– Hygiene– Waste disposal

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Natural resourcesAbiotic resources

– Light– Air– Water– Soil– Minerals

Pit mining, Canada en.wikipedia.org

Sierra Nevada, California

Landscape resources– Space, infrastructure– Diversity– Wilderness– Continuity/fragmentation– Connectivity

Biotic resources– Micro-organisms– Plants– Animals– Fungi

Cultural resources– Biodiversity– Open space– Recreational

landscapes

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Renewability of natural resourcesPerpetual resources

• solar radiation• tidal movement • wind• water flow

Even if virtually infinite, can be blocked and trapped or changed with dramatic effects.

Renewable resources• fresh water • oxygen• wood• biomassUnsustainable if consumption exceeds production.

Non-renewable resources• fossil fuels• minerals • fossil aquifers At one point it�s finished!

Windpark in Galicia, Spain.

Jog Falls, India

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Ecosystem functions Ecosystems have multiple functions

(processes required for its functioning, resource supply and maintenance)– Trophic processes

• Food web complexity• Biogeochemical interactions

• NPP• Decomposition

– Landscape processes• Patch and pattern formation• Microclimate control

• Successional development • Spatial flows

– Movement of organisms– Abiotic fluxes

• Continuity/fragmentation, corridors

– Biodiversity

http://wallpapers.pixxp.com/

Humans and ecosystems

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Connecting between human requirements and ecosystem functions

Or:

How to change our views from

“Humans versus Nature” to

“Humans with Nature”?

Or to “Humans within Nature”??

environmentalgeography.wordpress.com

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Ecosystem servicesUsing ecosystem functions and resources for human requirements

Kinds of ecosystem services (Millennium Assessment Reports www.millenniumassessment.org):

• Provisioning services – Energy, oxygen, water, materials and commodities

• Regulating services– Flood and erosion control, decomposition, water purification,

natural enemies of pests, pollination

• Supporting services– Biodiversity (genetic, taxonomic, functional)

• Cultural services– Recreation, aesthetics, spiritual values, tradition

Trade-off between services at high density and economic growthØ Provisioning at the expense of other services.

Therefore, sustainability requires weighing multiple services and optimization, based on knowledge and decision-making.

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Sustainable natural resource use

Promoted by• Stakeholder involvement• Legislation • Research, Monitoring• Information and data flow• Education • Public awareness• Citizen science• Consumer empowerment

At the local, regional, national and global scale

Implemented by• Management

• Protection

• Preservation www.dehelix.be

Photo: Kirk Prichard, Concern Worldwide

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Ecological footprintAmount of productive land and water required for an individual, a city, a

country, or humanity, to produce all the resources it consumes and to absorb all the waste it generates, using prevailing technology.

http://www.ew.govt.nz/enviroinfo/indicators/

Regional footprint

•�Direct' land occupied by a sector or activity.

• Land used elsewhere to provide imported

goods consumed locally.

•�Indirect� land used to produce the goods and services supporting any sectors or

activities.

• Including land required for waste disposal processes.

•�Energy� land (to compensate for CO2

emissions).

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More footprintsPer-capita footprint

Ecological overshoot =

Footprint – Biocapacity

= 0.5 (2007)

• Deficit due to use of reserves

http://www.ew.govt.nz/enviroinfo/indicators/More ecological indicators:

http://www.footprintnetwork.org/

http://www.footprintnetwork.orgPer-person resource demand (Ecological Footprint) and

resource supply (Biocapacity) in Israel since 1961.

Biocapacity varies each year with ecosystem

management, agricultural practices (such as fertilizer use

and irrigation), ecosystem degradation, and weather.

2005

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BiocapacityAvailable biocapacity in 1999:11.4 billion ha (11.4 x 109 x 104 m2) of biologically productive space (25%

of the Earth)2.3 - Oceans and

inland water 9.1 - Land

1.5 - Cropland3.5 - Grazing land3.8 - Forest land0.3 - Built-up land

http://www.footprintnetwork.org/Limitations of biocapacity analysis

• Exclusion of open oceans and less productive lands

• No space allocated for other species

• Use of agricultural productivity potential as the basis for equivalence

• Assumes even distribution of the global carbon budget

• Ignores carbon sequestration biocapacity.