# Presentation: 498606

## Integrating Economic and Ecological Models Across Spatial Scales to Assess Aquatic Species Vulnerability to Timber Harvest and Land Use Change in Freshwater Streams of the Southeastern U.S.

**Rex Schaberg****1****, Robert Abt****2****, Fred Cubbage****2****, **
**Pat Halpin****1****, Anne Hershey****3**** (P.I.s)**
**Ken Fortin****3****, Keli Goodman****3****, Peter Harrell****1****, **
**Kevin Potter****2****,  Jon Scott****2**** (Researchers)**
-  **(1) Duke University, (2) North Carolina State University, (3) University of North Carolina at Greensboro **

## Presentation Overview

- Provide a summary of study concept, study objectives
- Describe preliminary analysis plan
- Discuss research results: the first steps
- Solicit feedback on approach, and suggestions on pertinent data sets

## Study Objectives

**Develop integrated economic-ecological models to assess lotic ecosystem imperilment in the southeastern U.S.**
**Utilize biological, economic, spatial, and policy data to create models at varying levels of physical scale**
**Examine the role of forests in sustaining aquatic communities, including relative impacts of forest management, and sufficiency of forestry Best Management Practices (BMPs)**
**Integrate and synthesize data using GIS technology to produce improved assessment tools**

## Study Antecedents:  The NC Wood Chip Mill Study

- “Evaluate the role of chip mills forest harvest on the ecology and economy of NC”
- Pertinent Results:
- Aggregated large scale findings may mask substantial smaller scale variability
- Economic models effective at larger scales, ecological models require more specificity
- SE Forests more intensively harvested, harvests _shifted_ on landscape
- Assessing ecological consequences requires spatial data on harvests

## EPA STAR Research:Continues Economic-Ecological Integration

- What are the relative impacts of increased forest harvests on SE aquatic systems?
- May shifting harvest distribution alter potential impacts on aquatic communities?
- Introducing harvest pollution (sediment)
- Reduction in beneficial inputs to streams
- Are forestry Best Management Practices (BMPs) sufficient for aquatic protection (e.g, SMZs)?

## Aquatic Background

- Southeastern aquatic systems contain the nation’s richest and most biodiverse assemblages of aquatic taxa
- 40% of North American aquatic insects
- 63% of US fish species (500 species)
- 850 species of mussels, clams, aquatic snails
- The 13 state southeastern region represents 24% U.S. land area, 20% U.S. cropland, 41% U.S. timberland

## Environmental Stressors

- Stressors impacting southeastern aquatic systems include:
- Habitat loss and habitat fragmentation
- Dams, reservoirs, water quality pollution barriers
- Invasive species
- Pollution
- Agriculture, urban development, forestry operations
- Physical and trophic disturbance of historical riparian associations
- Nutrients, temperature, flow regime, channel structure,  in-stream woody debris
- f (evolutionary interactions with forested landscapes)

## Southeastern region contains 54% of the U.S. populations of “at risk” freshwater fishes (435 species)1

- Vulnerable Aquatic Systems

- 1  TNC: Rivers of Life 1998

## Research Overview

- Watershed approach, nested scales
- 13 state southeastern region (corresponds to USFS Forest Inventory data)
- North Carolina subregions
- Case study watersheds within NC Piedmont
- Use GIS to spatially integrate data and motivate new models
- Data Collaborators: EPA, USDA FS, USGS, TNC, NC DFR, NC DWQ, NC NHP, NC WRC

## Modeling Objectives

- _Economic_:  A land-use adjusted, watershed based, econometric model of timber growth and removal for southern FIA region to 2050
- SubRegional Timber Supply Model (SRTS)
- _Spatial_: Estimates of spatial distribution of harvests, and land use change , relative to stream networks, within the study areas 1984 to 2000; with projections to 2050
-  GIS change detection model of forest loss

## Modeling Objectives (cont.)

- _Aquatic_:  Watershed specific multimetric (e.g., B-IBI) measures of aquatic condition, and multivariate analysis of harvest impacts on stream fauna
- _Policy_:  Conceptual models evaluating strengths and weaknesses of existing forestry BMPs in protecting stream fauna (scales: region-wide to local), and identifying options for improved methods

## Watershed  Emphasis

- Adapt FIA data, census data to watershed reporting units (8 digit HUCs)

- FIA Southern Region 8 digit HUC codes

## Slide 13

## NC Spatial (GIS) Context

- 30 Meter TM path/row map of NC

- 15-35

- 16-35

## North Carolina Subregional Analysis

- Priority Aquatic Conservation  Areas Within NC

- Case Study: Upper Tar-Pamlico
- HUCs:  03020101,03020102, 03020103

- Map Data:  TNC, NC NHP

- 16-35

- 15-35

## NC Small Area Case Study

- Two Piedmont NC stream systems
- Similar fauna and hydro-geomorphology
- High biodiversity, NC WRC aquatic faunal surveys
- Little Fishing Creek (HUC 03020102)
- Relatively unimpacted reference stream (survey 1995)
- Swift Creek (HUC 03020101)
- Experienced significant timber harvest during the late 1980s and 1990s, little other anthropogenic impact (survey 1993)

## Swift Creek, NC

- Photo: John Alderman

## Swift Creek, NC

- Photo: John Alderman

## Large Scale Analysis 

- What trends may affect aquatic vulnerability in SE watersheds?  Data (emphasizing forestry) include:
- NRI land use, land use change data
- shifts in urban, agricultural, forest extent
- Census data
- State regulatory and forest policy data (BMPs, SMZs)
- USDA Forest Service Forest Inventory data (FIA)
- Shifts in forest harvest locations, harvest intensity
- Initial approach similar to EPA DRASTIC groundwater model:
- 			Index = i SiWi  (s=stressors; w= weights)
- Can smaller scale NC analysis inform/improve larger scale index weights?

## Modeling Trends in Land Use and Forest Economics

- SubRegional Timber Supply (SRTS) econometric model used to simulate a land-use-adjusted model of timber inventory, growth, and removals within watersheds until 2050
- 	i) 13 SE states
- 	ii) selected watersheds in NC
- FIA inventory data, census data, NRI land use, and land use change data 1982-1997
- SRTS minimum modeling scale
- ~1million acres

## Forest Service FIA Data Sampling

- Data reported by county
- Data masked for owner confidentiality

- FIA data “geocorrected”
-  to 8 digit HUC

- ~ 85,000 obs.

## Softwood Harvest Volume by 8 digit HUC Code

- Preliminary SRTS output

## detect spectral change between two satellite images
Magnitude / direction vectors
“Tasselled Cap” Radiometric transformation yields
brightness
greenness
wetness 
as three components of the image

- Magnitude / direction vectors
- “Tasselled Cap” Radiometric transformation yields
_**brightness**_
_**greenness**_
_**wetness **_
- as three components of the image

**GIS Change Vector Analysis CVA****)**

## 1989-1993 CVA Image

**Sectors of Change:**
- red = loss in greenness
- green = gain in greenness
- blue = loss in wetness,
- greenness, and brightness
- yellow = gain in wetness,
- greenness, and brightness
- magenta = complex change
- gray = no change

**Change ****Vector**** Analysis (CVA)**

## NC DWQ Biomonitoring Data

- Intolerant taxa (IT) decline with > silt
- IT exhibit wide variability in low silt
- 	=> multiple factors impact species mix
- 	=> need metric calibrated for timber effects

- Total Intolerant Taxa vs. % Silt

- NC DWQ biomonitoring data for NC  1984 – 2000
- NC DWQ “Intolerant Taxa”

## Preliminary BMP Analysis

- Completed draft report of 13 SE State BMP policies and procedures (Scott, Cubbage)
- Findings:  BMPs essentially voluntary in all states
- NC generally among most protective aquatic standards
- Published BMP compliance high (95% in NC), but reporting process validity is problematic-- WQ emphasis
- Additional types of NC forest harvest data:
- Forest practice guidelines (FPGs).  ~ 4000 annually (NC)
- BMP compliance surveys; historical, ongoing 2000-2003
- Landowner collaborator data in case study area

## Next Steps

- Continue interdisciplinary synthesis of data
- Iterative analysis, integrating findings among various scales
- Focus on development of methods, assessment tools
- Make good use of:
- 		Comments?
- 		Suggestions?