Agroecology Ecological understanding of farming systems 4. Ecosystem services

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1 Ben-Gurion University of the Negev Agroecology Ecological understanding of farming systems 4. Ecosystem services Human requirements Natural resources Ecosystem functions Ecosystem services Ecological footprints BBoeken Biocapacity 1

2 Human requirements Other physical needs Safety Hygiene Waste disposal Physical supplies Air Space Water Food Fiber Shelter Medicine Cultural needs Pleasure Art Knowledge Religion Nature Biodiversity Wildlife Travel Technology Industry Quantity and quality depend on Dependency on natural ecosystems Human control of supply and production Population density Awareness and empowerment 2

3 Natural resources Abiotic resources Light Air Water Soil Minerals Biotic resources Micro-organisms Plants Animals Fungi Pit mining, Canada en.wikipedia.org Landscape resources Space, infrastructure Diversity Wilderness Continuity/fragmentation Connectivity Sierra Nevada, California Cultural resources Biodiversity Open space Recreational landscapes 3

4 Renewability of natural resources Perpetual 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 biomass Unsustainable 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 4

5 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 5

6 Humans and ecosystems 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 6

7 Ecosystem services Using ecosystem functions and resources for human requirements Kinds of ecosystem services (Millennium Assessment Reports 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 growth! Provisioning at the expense of other services. Therefore, sustainability requires weighing multiple services and optimization, based on knowledge and decision-making. 7

8 Sustainable natural resource use Implemented by Management Protection Preservation Photo: Kirk Prichard, Concern Worldwide 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 8

9 Ecological footprint Amount 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. 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 CO 2 emissions). 9

10 More footprints Per-capita footprint Per-person resource demand (Ecological Footprint) and resource supply (Biocapacity) in Israel since Biocapacity varies each year with ecosystem management, agricultural practices (such as fertilizer use and irrigation), ecosystem degradation, and weather Ecological overshoot = Footprint Biocapacity = 0.5 (2007) Deficit due to use of reserves More ecological indicators: 10

11 Available biocapacity in 1999: Biocapacity 11.4 billion ha (11.4 x 10 9 x 10 4 m 2 ) of biologically productive space (25% of the Earth) Oceans and Land inland water Cropland Grazing land Forest land Built-up land 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. 11