Ecological Archives A021-139-A2

C. M. Riseng, M. J. Wiley, R. W. Black, and M. D. Munn. 2011. Impacts of agricultural land use on biological integrity: a causal analysis. Ecological Applications 21:3128–3146.

Appendix B (TABLE B1). Site variable means (mean and standard deviation of environmental, physical habitat, water chemistry, and invertebrate variables for sampled sites). Invertebrate tolerance was summarized by both national and regional tolerance values.

Study Units National Coastal Plains
GCP DLMV
Number sites 226 29 25
Parameters Mean SD Mean SD Mean SD
Watershed/Landscape            
Drainage Area (km²) 323.98 706.94 145.86 53.31 15.04 8.50
Basin Elevation (m) 521.24 516.04 106.72 23.37 15.34 3.35
Base Flow Index 51.98 14.87 50.95 7.20 58.96 4.01
Basin agriculture (%) 46.39 28.14 32.25 15.49 61.04 15.79
Basin cropland (%) 33.35 28.40 24.30 14.67 43.43 12.20
Riparian forested wetland (%) 5.93 11.93 35.55 6.67 4.20 5.55
Water chemistry/Temperature            
Dissolved inorganic nitrogen (mg/l) 1.70 1.95 0.70 0.78 3.29 2.51
Conductivity (µsm) 389.35 239.37 105.48 70.36 142.60 47.68
Excess conductivity (µsm) 119.79 137.94 20.96 15.26 87.95 40.53
Total phosphorus (mg/l) 0.15 0.24 0.04 0.01 0.11 0.12
Suspended organic carbon (mg/l) 1.26 2.04 0.82 0.61 2.41 3.85
Total suspended solids (mg/l) 33.72 76.52 14.78 6.51 26.48 85.67
Temperature (°C) 20.81 3.58 21.97 1.30 19.45 2.03
Invertebrate metrics            
EPT richness 10.33 4.77 9.79 2.54 6.32 2.43
Mean invertebrate tolerance-national 5.06 0.82 5.20 0.26 4.82 1.02
Intolerant individuals (%)-national 32.06 21.77 24.23 11.44 19.44 15.25
Mean invertebrate tolerance-regional 5.10 1.06 5.76 0.33 5.93 0.67
Intolerant individuals (%)-regional 39.15 28.30 15.82 11.14 10.14 11.05
Stream habitat            
Cobble and gravel (%) 24.51 28.36 2.13 6.32 1.33 4.94
Woody Debris (%) 20.01 22.73 58.31 24.20 15.34 17.29
Not embedded (%) 33.46 33.03 3.16 5.00 67.85 44.59
D84 (cm)/hydraulic radius 249.43 421.01 20.09 70.76 25.64 59.48
Channel shear stress (Pa) 9.04 17.96 2.52 1.61 3.84 7.48
Water surface gradient 0.00327 0.00515 0.00086 0.00051 0.00191 0.00248
Proportion riffle habitat 13.41 17.22 0.01 0.03 0.00 0.02
Study Units Western Arid Midwest Plains
CCYK USNK CNBR
Number sites 29 29 26
Parameters Mean SD Mean SD Mean SD
Watershed/Landscape            
Drainage Area (km²) 652.01 1421.79 839.52 1104.95 410.87 398.95
Basin Elevation (m) 697.58 343.60 1642.53 357.60 654.68 127.95
Base Flow Index 57.90 13.46 75.63 4.30 41.53 8.42
Basin agriculture (%) 35.93 30.80 20.04 24.74 47.46 24.32
Basin cropland (%) 30.64 27.63 15.07 19.44 46.70 24.41
Riparian forested wetland (%) 1.38 2.15 1.28 1.92 2.70 3.16
Water chemistry/Temperature            
Dissolved inorganic nitrogen (mg/l) 1.19 1.34 0.72 0.96 1.67 1.13
Conductivity (µsm) 321.83 123.98 459.07 299.62 571.81 222.38
Excess conductivity (µsm) 75.83 57.33 173.54 238.23 200.15 199.03
Total phosphorus (mg/l) 0.11 0.08 0.05 0.04 0.66 0.41
Suspended organic carbon (mg/l) 0.70 0.56 0.43 0.28 4.13 2.19
Total suspended solids (mg/l) 20.90 30.44 13.97 11.66 167.43 148.75
Temperature (°C) 18.89 3.26 18.67 3.33 23.55 2.93
Invertebrate metrics            
EPT richness 10.41 4.78 11.41 4.99 5.80 2.66
Mean invertebrate tolerance-national 5.52 0.53 4.49 0.58 5.47 0.71
Intolerant individuals (%)-national 46.55 25.26 45.39 22.56 10.91 14.86
Mean invertebrate tolerance-regional 5.03 1.10 5.09 1.25 4.52 0.53
Intolerant individuals (%)-regional 47.46 24.68 45.86 21.92 48.24 23.26
Stream habitat            
Cobble and gravel (%) 47.84 28.08 37.88 25.23 0.00 0.00
Woody Debris (%) 4.52 6.92 4.61 6.28 22.18 19.50
Not embedded (%) 42.08 23.89 42.37 25.65 1.36 2.47
D84 (cm)/hydraulic radius 395.68 389.05 454.37 461.41 6.83 16.80
Channel shear stress (Pa) 19.01 11.58 27.33 41.82 3.34 2.41
Water surface gradient 0.00763 0.00741 0.00786 0.00922 0.00108 0.00059
Proportion riffle habitat 0.32 0.40 0.81 1.36 0.00 0.00
Study Units Midwest Plains
OZRK UMIS WHMI
Number sites 30 29 29
Parameters Mean SD Mean SD Mean SD
Watershed/Landscape            
Drainage Area (km²) 170.92 95.79 230.87 126.28 98.40 67.44
Basin Elevation (m) 344.43 72.65 357.47 57.98 301.28 34.36
Base Flow Index 38.66 6.92 57.81 6.25 34.73 8.07
Basin agriculture (%) 38.00 22.80 56.03 21.45 82.77 6.81
Basin cropland (%) 0.47 1.59 34.22 23.79 75.85 13.22
Riparian forested wetland (%) 0.72 0.83 1.02 1.14 0.23 0.97
Water chemistry/Temperature            
Dissolved inorganic nitrogen (mg/l) 0.71 1.12 1.90 2.59 3.67 1.69
Conductivity (µsm) 365.27 70.00 510.07 186.78 624.31 113.52
Excess conductivity (µsm) 52.73 20.41 149.22 123.47 204.14 71.31
Total phosphorus (mg/l) 0.02 0.02 0.12 0.08 0.13 0.11
Suspended organic carbon (mg/l) 0.16 0.18 1.15 1.83 0.76 0.88
Total suspended solids (mg/l) 12.02 12.38 17.16 27.87 10.59 5.42
Temperature (°C) 24.38 3.15 19.36 4.06 20.19 2.64
Invertebrate metrics            
EPT richness 14.50 3.00 11.93 6.73 11.14 2.45
Mean invertebrate tolerance-national 5.38 0.58 4.87 1.19 4.83 0.51
Intolerant individuals (%)-national 44.19 16.71 27.98 19.73 33.47 15.94
Mean invertebrate tolerance-regional 5.08 0.71 5.77 0.90 3.66 0.51
Intolerant individuals (%)-regional 34.72 16.70 23.13 17.32 84.92 8.95
Stream habitat            
Cobble and gravel (%) 59.99 19.33 11.84 18.82 28.12 20.08
Woody Debris (%) 2.60 4.65 28.29 16.62 24.38 11.50
Not embedded (%) 73.30 6.96 11.02 12.22 26.60 14.45
D84 (cm)/hydraulic radius 646.97 629.42 69.47 175.33 306.68 430.02
Channel shear stress (Pa) 8.17 3.85 3.30 3.84 3.48 2.93
Water surface gradient 0.00309 0.00127 0.00122 0.00113 0.00210 0.00226
Proportion riffle habitat 0.40 0.33 0.13 0.14 0.29 0.45

[Back to A021-139]