SLIDE 1
Indicators of Sustainability & Landscape Diversity
Katherine and Nicole
SLIDE 2 What is Sustainability in Agriculture?
How would you explain how farms practice sustainability to someone interested in this class?
- Maintains the resource base upon which it depends
- relies on a minimum of artificial inputs
- manages pests and diseases through internal regulating
mechanisms (biological controls)
- able to recover from disturbances caused by
cultivation and harvest
- needs economic and cultural support of practices
SLIDE 3
Reference points
natural ecosystems & traditional agroecosystems “The greater the structural and functional similarity of an agroecosystem to the natural ecosystem in its biogeographic region, the greater the likelihood that the agroecosystem will be sustainable.”
SLIDE 4
Traditional Agroecosystems
What makes a traditional agroecosystem sustainable and why?
SLIDE 5
Food for thought
Describe an aspect of traditional farming systems that could be applied widely in conventional farming systems if sustainability were a primary goal.
SLIDE 6
Measuring Sustainability
SLIDE 7 The Productivity Index
How does PI differ from mere production measurements? Productivity Index = Total Biomass accumulated Net Primary Productivity
- NPP = GPP - Respiration
- low of 1, high of 50 for natural ecosystems
- assumes a positive correlation between return of
biomass to a system and the system’s ability to produce a harvestable yield
SLIDE 8
Ecological Parameters
Soil - long term, short term
hydrogeological factors - on farm drainage rates, surface water flow, ground water quality biotic factors - microbes, turnover, balance of beneficials and pests, niche diversity and overlap, native plants and animals Ecosystem level - production output, inputs and origins, nutrient cycling, community complexity
SLIDE 9 Assessing Soil Health
How can farmers test soil health and quality?
- ease of cultivation
- water holding capacity
- earthworm presence
- signs of erosion
SLIDE 10
Cropland Intensity in US
SLIDE 11 Social Conditions
- rural sociology, participatory approaches
- parameters will be subjective and location specific
i.e. educational attainment, drug use, physical health, average farm income, farmer networks
SLIDE 12 Socioeconomic parameters
- per unit production costs/returns
- off farm externalities and costs resulting from farming
practices
- equitability of return to farmer
- extent of age, race, and gender empowerment
- degree of sharing agrarian values
SLIDE 13 Bringing data together
look at just one factor
- agroecological framework
- existing data sets
- comparative analysis
- Amoeba diagram, p.308
- Multi-scale systems analysis
SLIDE 14 Chinese Village Agroecosystem
Erle Ellis studied cycling of nutrients
Noted changes in the nitrogen cycling as farmers moved towards using inorganic fertilizers.
SLIDE 15 Chapter 22: Landscape Diversity and Agroecosystem Management
Three basic components of the agricultural landscape:
- Areas of agricultural production
- Areas of reduced human influence (i.e.
pastureland, hedgerows, other border areas, agroforestry, etc.)
SLIDE 16 Analyzing the Landscape
- Typical agricultural landscape: fragmented/ patched
environment
- landscape ecology: how the movement of organisms,
the interaction of organisms among different patches, and how landscapes affects another
- Why is landscape ecology important in agroecology?
SLIDE 17 Managing the Landscape
Landscape-level management: the inclusion of natural ecosystems and local biodiversity in management decisions and planting Two key principles:
- 1. Diversify the agricultural landscape by varying
their level of disturbance
- 2. Reduce negative impacts by decreasing the
usage of inputs
SLIDE 18
Case Study: Tlaxcala, Mexico
Problem: periodic rain occurs in huge rainstorms and food is grown on steep slopes-- concerns about erosion Potential solutions? Their solution: hillside terrace systems that collect runoff rainwater through water and sediment catching basins (cajetes)
SLIDE 19 Farm Borders and Edges
- When a transitional area of vegetation develops
between two different biomes, an ecotone results
- The edge effect occurs when the largest and
most dense area of the habitat is the ecotone
- Why is the edge effect significant?
- Greater diversity of species, buffer zone,
prevents fires from moving, etc.
SLIDE 20 Key Points
- Systems thinking
- vs. tunnel vision
- Linking
agroecosystems and natural ecosystems
land usage
SLIDE 21 Mexico: Traditional Agriculture as a Foundation for Sustainability
Indigenous’ agricultural practices, colonization and the idea of ‘progress’, development of unsustainable agricultural practices
Goal: develop the American model of agriculture
SLIDE 22
Scenario: Mexican Traditional Ag.
Roles: Member of the Mexican gov’t, traditional farmer, migrant worker, traditional farmer who has switched to conventional agriculture Context: Agriculture within the next 20 years Potential solution?
SLIDE 23 NYT: “Organic Agriculture May be Outgrowing its Ideals”
- Did this article surprise
you?
that organic practices actually are sustainable?
SLIDE 24 National Sustainable Agriculture Standard
- Leonardo Academy
- developing a national standard with 58
people on committees
- consideration of social, environmental,
economic factors