Gen Bio

1. Principles of Urban Ecology
Steward T.A. Pickett
Cary Institute
of Ecosystem Studies

2. What’s a principle?

3. Components of Theory
• Domain
• Assumptions
• Concepts
• Definitions
• Facts
• Confirmed generalizations
• Laws
• Models
• Translation modes
• Hypotheses
• Framework
Pickett et al. 2007

4. Senses of “urban”
• Broad – inclusive
• Narrow – specific

5. Goal
• Framework
• Model building

6. Themes
• Components
• Form
• Change
• Functioning

7. Components of the system

8. P1
• Cities are about people and ecosystems.
– Human ecosystems

9. The Ecosystem Concept
Sir Arthur G. Tansley (1871-1955)

10. Biotic complex Physical complex
Social complex Built complex
The Tansleyan Ecosystem Concept
The Human Ecosystem Concept

11. P2
• Cities have multiple and changing forms.

12. Central Business District
Transitional zone: recent immigrants, deteriorating housing, factories,
abandonment
Working class zone: single family tenements
Residential zone: single family homes with yards and garages
Commuter zone: suburbs
Burgess Model

14. Antoni 2001

17. P3
• Cities are mosaics extending into
surroundings.

18. Cadenasso

19. Patch dynamics
• Applies to cities
• Hierarchical
• Gradients and fields

20. Patch Dynamics
Creation and Alteration of Spatial Heterogeneity through Time
Mosaic Configuration
Patch Types
Patch Adjacency
Slow Template
Patch Generation
Disturbance
Ecological
Engineering
Patch Change
Demographics
Succession
Flux
Patch
Contrast
Flux
Identity
Boundary
Structure
Pickett, Cadenasso

21. Social processes

22. P4
• Planned, opportunistic, incremental,
incidental.

23. Components of change
• Urban design
• Urban planning
• Topography
• Ecology
• Social-cultural
• Economic

24. P5
• Urban designs as experiments.
Felson, Pickett (2005)

25. Jordan Cove, CT
Control development
Traditional
BMP

26. P6
• Social, economic, cultural processes
influence biophysical processes.

27. 1970
1990
Grove, Burch

28. P7
• Social, cultural, economic complexity.

29. Components of social complexity
• Property regimes
• Households and individuals
• Social status
• Economic status
• Lifestyle grouping
• Social identity
• etc.

30. Perceive high
value of parks
Perceive low
value of parks
Troy et al.

31. IKONOS Image
Vegetation
Parcels
PROW
Vegetation
Private Land
Vegetation
Fine Scale Analysis
Grove, Troy, O’Neil-Dunne

32. Biophysical functions

33. P8
• Remnant soils, waters, vegetation.

35. Nitrogen retention
Suburban Forested Agriculture
----------------- kg N ha-1 y-1 --------------
Inputs
Atmosphere 8.7 8.7 8.7
Fertilizer 13.9 0 100
TOTAL 22.6 8.7 108.7
Outputs
Streamflow 6.5 0.52 16.4
Retention
Mass 16.1 8.2 92.3
Percent 71 94 85
Groffman, Belt, Fisher

36. P9
• Biodiversity multifaceted and present.

37. Mocking bird Mourning dove Catbird
Robin Grackle Pigeon Warren, Nilon, Wolf

38. Methodological principles

39. P10
• Study-specific definition of urban.

40. P11
• Abstract urban gradients.

41. NY
CT
LI
NYBG
VCP
PBP
SWP
CEC
MRG
MLP
MSP
MSF
HSF
New York City
McDonnell et al 1990

42. P12
• Human perception as links.

43. Pickett, Cadenasso (2008)

44. Practical principles

45. P13
• Flux of water, and water infrastructure.

46. N. Law and L. Band

47. Water principle
• Sites of cities
• Urban design
• Future demands.

48. P14
• Exotic species functions.

49. Distributions of exotic herbs in riparian zones
0.00
0.05
0.10
0.15
0.20
0.25
0.30
0.35
UPPER MIDDLE LOWER
frequency
upland
wetland
upland/wetland
G. Brush et al. in prep

50. P15
• City form and shared needs
– Role of elites
– Non-stationary roles
– Non-overlapping agency
– Environmental injustice.

51. Boone

52. P16
• Utility of data requires continual dialog.

54. Review of the principles
• Human ecosystem
• Multiple forms
• Extensive spatial mosaics
• Intention, opportunity, incidental,
constraint
• Design as experiment
• Role of social pattern and process
• Social complexity …

55. • Retain remnant soils, waters, vegetation
• Biodiversity multifaceted, value
• Urban definitions various
• Abstract gradients of urbanization
• Human perceptions and actions
• Flux of water, water infrastructure
• Exotics and function
• City form: equity and control
• Application through dialog.

56. Conclusions
• Transdiciplinary concern
• Heterogeneous, changing subject
• Suggests emerging framework
• Open to new insights
• Context for specific tests.