# Presentation: 857229

## Conceptual Models for NPS I&M Networks

- Conceptual Models for NPS I&M Networks

***John E. Gross***
***Southeast Region I&M Meeting***
***January 4, 2004***

## Two views of conceptual models:

-  central element of monitoring plan and program
-  useful for organizing and communicating complex system dynamics
-  improved understanding
-  great for justifying vital signs (will be good for interpretation)

-  a real struggle – another WASO requirement
-  largely a waste of time
-  “our oversight committees hate them”
-  a duplication of the obvious

##  Goals and observations from networks 

-  Goals and observations from networks
-  Examples, alternative models, etc
-  Recommendations
-  Resources

## Goals for conceptual models in the monitoring plan

-  Formalize current understanding of system dynamics,
-  Explicitly connect key processes to system dynamics,
-  Identify linkages of processes, esp. across disciplinary boundaries,
-  Communicate important interactions and feedbacks,
-  Illustrate linkages between important processes and vital signs.

## Refer to the monitoring plan checklist (download from I&M web site)

| Chapter 2 – Conceptual Ecological Models |
| --- |
| Have the major ecosystems within the network of parks been identified? |
| Has the network effectively used conceptual models to help organize, summarize, and communicate complex information (on ecosystems)? |
| Are the conceptual models sufficiently detailed to provide support for selecting, justifying, and interpreting potential vital signs? |
| Are the tables and figures, and the narrative supporting the tables and figures in this chapter, clear, complete, and understandable? |
| Is relevant literature cited; do citations provide valid, credible, and sufficient scientific justification for the models? |
| Is the treatment and presentation of conceptual models systematic, synthetic and integrative such that interactions within and linkages among ecosystems are described? |

## What is a conceptual model, really?

-  table of “relationships”?
-  picture of system?
-  box and arrow diagram?
-  narrative?

## In the end, most network monitoring plans include

-  box and arrow diagrams (one sort or another)
-  eventually, both control and “driver-stressor” models
-  tables with important drivers, responses
-  narratives describing models

**Models are expressions of hypotheses.  Most models need periodic revision.**

##  Many model formulations are useful

-  Many model formulations are useful
-  no single model type meets all needs
*“**All models are wrong, but some are useful” *
-  Networks use multiple model structures because it’s easier & faster to construct need-specific models,
-  Hierarchically structured sets of models have advantages
-  can “begin at the beginning”,
-  systematic means to added detail over time,
-  coherent set of models with obvious linkages,
-  Craft is important – it takes time to design diagrams.

## Hierarchical sets of models

- Generalized environmental model

- Landscape-scale diagrams

- Species, site, or habitat models

- Ecosystem

- Stage-setting; global and regional scale drivers and responses

- Environmental gradients; broad-scale drivers; linkages between systems (disturbance, land use)

- Dynamics; broad to fine scale factors

- Model Scale

- What it communicates

- Detailed mechanisms & feedbacks, stressors->VS

## First steps

*First steps*
- Define the objectives for the models
- Who are the audiences and what are purposes?
- What “distinct” systems were identified by ecologists and managers?
- What important dynamics do you want to accommodate?
- Are there key linkages between systems (i.e., higher-level needs)?

## First steps

*First steps*
- Define the objectives for the models
- Create or adopt a high-level model to:
- Provide overarching context
- Shared reality of system
- Prevent oversight

## Constructing models

- What works (mostly ...)
-  well-organized workshop w/ NPS staff, topical experts, modeler
-  _*collaborative*_ projects with intermediate milestones
-  2 or 3 ecologists working together
-  a network ecologist in their area of expertise

- What doesn’t work (almost always)
-  a “creative” workshop w/o experienced people in each group
-  independent contracts
-  one-size fits all approach (i.e., uniform model structure)
-  network staff attempting to create all models themselves

## Some examples

-  Descriptive ecosystem diagrams
-  High-level, aggregated “holistic” models
-  State and transition models
-  ‘Control’, mechanistic models
-  Conceptual diagrams
-  Aggregate, box-and-arrow diagrams (hybrid)

## Descriptive diagrams – good for ‘setting the scene’

- (IAN Newsletter 5:  www.ian.umces.edu)

- (Mutel and Emerick 1992)

- (Knight 1994)

## Generalized models

- GLOBAL CLIMATE

- TIME

- POTENTIAL BIOTA

- PARENT MATERIAL

- TOPOGRAPHY

- Regional atmospheric
- resources & conditions

- Disturbance regime

- Ecosystem Processes

- Functional groups

- Soil / water resources & conditions

- (Chapin et al. 1996)

*Generalized models*

## NCPN modifications to Chapin model

## Slide 17

## Slide 18

## Slide 19

##  System dynamics may determine model structure

-  System dynamics may determine model structure
-  state and transition models
-  arid, semi-arid systems
-  some aquatic systems
-  control model
-  causal loop, process, mechanistic model
-  picture model
-  EPA-type stressor model

*Systems are place-based!  This is how most of us think about the world.*

## Ponderosa pine state and transition model

-  grassy understory
-  ~ 100 trees/ac
-  frequent “cool” ground fires
-  fires extensive and patchy
-  minimal influence by exotics

**Moderately dense even or mixed-aged stand**
-  many saplings
-  infrequent fire due to suppression or non-continuous ground fuel
-  fires likely to be intense, extensive, and stand-replacing

- Overgrazing, fire suppression

- Prescribed burning, thinning

**Dense even-aged stand**
-  stand-replacing fires frequent or infrequent
-  understory vegetation sparse
-  fuel load large and continuous
-  fires intense and spatially extensive

- Thin and burn?

- Intense crown fires

## Ponderosa pine control model

- Seedlings
- (#/ha)

- Seed
- bank

- Saplings
- (#/ha)

- Trees
- (#ha)

- Snags
- (#/ha)

- Survival
- and growth

- Survival
- and growth

- Survival
- rate

- Decay,
- combustion

- Seed production / persistence
- (pollination, granivory, decay, etc)

- Fire intensity

- Fuel continuity(stand)

- Fire frequency:
- (suppression, prescribed burning, lightning)

- Grazing,
- thinning

- Fire extent

- Fuel continuity(landscape)

- This model is structurally correct

- Fire submodel

## TNC - 

**TNC -**

## Slide 24

## Alternative ponderosa model – GRYN stressor model

## (Knight 1992)

## From: http://www.coastal.crc.org.au/bremer/ecosystem_dynamics.html

- Figure 1: Primary water column nutrient cycles in Bremer River and inputs of phosphates, silicates, DOC, DON and inorganic nitrogen.

- A conceptual model of the Bremer River ecosystem has been developed that is suitable for (1) developing a coherent overview of relevant ecological and biogeochemical processes affecting water quality and also for (2) design of a relevant survey sampling program and (3) subsequent design of a numerical simulation model to test water quality improvement strategies.

## From: http://www.coastal.crc.org.au/bremer/ecosystem_dynamics.html

## Model strengths and weaknesses

- Control models
-  accurately represent feedbacks and interactions
-  usually most realistic structure
-  insights from construction
-  often complicated and hard to communicate
-  state dynamics may not be apparent

- State and transition
-  clear representation of alternative states
-  can be simple
-  excellent communication with most audiences
-  generally lack mechanism
-  usually too general to directly link to vital signs

- Driver-stressor models
-  provide clear link between agent of change and VS
-  simple and easy to communicate
-  no feedbacks
-  few or no mechanisms
-  frequently inaccurate and incomplete

## Match model structure to audience and need

| What you want to communicate | Model type |
| --- | --- |
| General system traits | Generalized model – picture or box & arrow |
| System dynamics | State & transition
Mechanistic diagram
Picture diagram |
| Links & feedbacks | Mechanistic diagram
Picture diagram |
| Driver – vital sign links | EPA stressor diagram |

## A bit on the craft ...it does make a difference!!!

-  align boxes, both horizontally and vertically
-  use line weights to show significance of linkage
-  avoid shaded boxes that photocopy poorly
-  use few colors and shapes
-  aggregate lines when possible
-  maximize ‘content ink’

## Craft matters – help readers by grouping related elements, aligning elements, and minimizing crossed lines.

- Schiller et al. 2001.  Cons. Ecol 5(1)19.

- These are the same!

## Craft matters!

- Extensive land use

- Disturbance regime

- Intensive land use

- Global change

- Ecological flows

- Changes in effective reserve size

- Edge effects

- Crucial habitat

- Ecosystem condition

- Ecosystem resilience

- Values:
- Wilderness
- Viewshed
- Night sky
- Soundscape

- Lithosphere      Hydrosphere           Biosphere             Atmosphere     Cryosphere

- Some aspects may be non-spatial

## What would the ideal conceptual modeling workshop include?

-  good background material, mailed to participants 3 weeks prior
-  I&M program, model goals, example models, workshop goals
-  glossary of terms & table of contents
-  park info: mgmt issues, natural resources (table if multiple parks)
-  information organized by working group (aquatic, etc.)
-  managers, ecologists, “drawers” in each group (3-6 people/group)
-  LCD projector and white board for each breakout group
-  form to describe each model:
-  system it represents
-  key features / interactions
-  mgmt levers
-  indicators and justification
-  information sources (citations, people, web sites, etc)

## What does the ideal monitoring plan Chapter 2 include?

-  Introduction / background. Very short justification / goals
-  Organized table listing all models, with figure and page numbers
-  Overall description of models – more aggregated, scales, etc.
-  Clear diagrams and tables
-  Explanatory narrative that matches and refers to figures
-  Pertinent citations, all in the bibliography
-  and, of course, models that meet all the criteria in the checklist

## I&M Conceptual modeling web page:

- I&M Conceptual modeling web page:
-     **www.nature.science.nps.gov/im/monitor/conceptual_models.htm**
**    **
- Integration and Application (IAN) http://www.ian.umces.edu
- Maddox et al.  1999 – best single paper
- Pugent Sound Conceptual Models
- Gulf of Alaska Ecosystem Monitoring (GEM)
- Westernport Bay Conceptual Model document (Oct. 2003)
- River models (Australia)  http://www.healthywaterways.org/
- USDA NRCS state and transition models (Brandon Bestelmeyer)
- Bremer R. model:
- 	http://www.coastal.crc.org.au/bremer/ecosystem_dynamics.html