Biological Condition July 29, 2014

Transcription

1 Biological Condition July 29, 2014 Presented by Mark Southerland (Versar) 1

2 Biological Condition Biology Knows Best, but no group tells all Important to consider 2 or more taxonomic groups Benthic macroinvertebrates are most diverse and standard for evaluating condition Clinch-Powell is biodiversity hotspot for Fish (14 species endemic to upper TN River basin) Mussels (48 species with 4 endemic to C-P) Data not available for other groups such as salamanders 2

3 Biology (Response) Data Benthic macroinvertebrate EPT 136 sites EPT (mayfly, stonefly, caddisfly) taxa are generally indicative of healthy streams CPCRI dataset from TVA Fish IBI 136 sites Fish are good complement to EPT Fish are hosts for mussels CPCRI dataset from TVA Mussel Condition 38 sites BPJ (best professional judgment) extrapolation of sites (mainstem reaches) covers 407 catchments CPCRI exercise 3

4 Method Steps: 1. Gather biology data for 3 parameters (response variables) 2. Gather predictor data (same wall-to-wall predictor variables as for WQ assessment) 3. Use statistical methods to establish relationships between predictor variables and response within appropriate ecoregions and habitat 4. Use relationships in model to predict response variables for appropriate unsampled catchments based on predictor variable values 4

5 Abiotic (Predictor) Data Likely Abiotic Predictors for Biology Landform Geology Channel form Upstream land use Response may vary based on ecoregion and/or stream size (mussels are limited to mainstems) 5

6 Omernik Level 4 Ecoregions 6

7 Benthic EPT Sample Locations 7

8 Fish IBI Sample Locations 8

9 Mussel BPJ Reaches 9

10 Strata (number of sites/mussel catchments) OMERNIK ECOREGION Mussels Benthic EPT Fish IBI Southern Limestone/Dolomite Valleys and Low Rolling Hil Southern Shale Valleys Southern Sandstone Ridges Southern Dissected Ridges and Knobs TOTAL Dissected Appalachian Plateau Cumberland Mountain Thrust Block TOTAL Cumulative Drainage Area Mussels Benthic EPT Fish IBI <50 mi < < > >

11 Data Too Sparse to Subdivide Too few samples in single ecoregions Weaker model in smaller streams Too few samples in single stream size class Model not significant in Appalachian Plateau alone Relationships are similar among ecoregion and size classes, so predictions made for entire Clinch-Powell Exception is restriction of mussel BPJ condition only to mainstems 11

12 Predictor Variable Selection Variable selection: correlations, stepwise regression, data-mining, etc. Example variables used in Biological Condition model: Category Landform Geology Channel form Land cover Variable Name Cumulative Drainage Area, Maximum Elevation, August Max Temperature, January Mean Precipitation Percent Clay, Percent Silt, Percent Sand Slope, Bankfull Discharge, Sinuosity, Mean Canopy Cover, Mean Groundwater Discharge Percent Disturbed Cumulative Area, Percent Cumulative Forest, Percent Cumulative Agriculture, Impervious Cover, Active River Area Urban, Road Length 12

13 Model Selection Variable selection: All wall-to-wall variables evaluated for significant relationship with each biology response: benthic EPT and fish IBI Variables used in Biological Condition model: Significant variables for benthic EPT and fish IBI combined in separate stepwise regressions to create best predictive models Mussel condition classes applied by BPJ (best professional judgment) to mainstem catchments (not modeled using predictor variables) 13

14 Benthic EPT Condition Model Positive (increasing with benthic EPT): Slope Percent Cumulative Forest Area Percent Natural Lands in Active River Area Negative (decreasing with benthic EPT): Percent Cumulative Disturbed Lands 14

15 25 Benthic EPT Condition Model Slope Percent Cumulative Disturbed Land Percent Cumulative Forest 25 Percent Natural Lands ARA

16 Benthic EPT Condition Model Percentage of EPT Taxa R 2 = Modeled Score Original Score 16

17 Predicted Benthic EPT Condition 17

18 Fish IBI Condition Model Positive (increasing with fish IBI): Bankfull Discharge Negative (decreasing with fish IBI): Drainage Area (mi2) Percent Cumulative Disturbed Lands 18

19 Fish IBI Condition Model 70 Cumulative Drainage Area (sq mi) 70 Bankfull Discharge Percent Disturbed Land Cumulative

20 50 Fish IBI Condition Model Percentage of Sites Original Model Excellent Good Fair Poor Very Poor 20

21 Predicted Fish IBI Condition 21

22 BPJ Mussel Condition in Mainstems Qualitative scoring of individual reaches of the Clinch River and major tributaries Based on input from biologists with local knowledge Scores are only be valid in the mainstems of these tributaries and the river because many headwaters have not been sampled or would not support mussels Conditions scores are categorical: VG = very good condition G = good F = fair P = poor full complement of spp present, most recruiting, all habitats occupied, pop'ns stable or growing most expected spp present, many recruiting, most habitats occupied, pop'ns stable some spp extirpated, only few spp recruiting, missing from some habitat several or all spp extirpated, low abundance, no significant recruitment 22

23 BPJ Mussel Condition 23

24 Biology MMI 3 Biology Parameters (Benthic EPT, Fish IBI, Mussels) Rank Normalization for Benthic EPT and Fish IBI: RRRR NNNNNNNNNN SSSSS = CCCCCCCCC RRRR 1 MMMMMMM RRRR Mid-range scores from four discrete mussel condition classes CCCCCCCCC 1 = 12.5, CCCCCCCCC 2 = 37.5 CCCCCCCCC 3 = 62.5, CCCCCCCCC 4 =

25 Biology MMI Combined and averaged to create Biology MMI Catchments without mainstems: (Benthic EPT + Fish IBI) / 2 = score Mainstem catchments: (Benthic EPT + Fish IBI + Mussels) / 3 = score 25

26 Predicted Biological Condition 26