Ecological Archives M071-004-A1

Karina J. Nielsen. 2001. Bottom-up and top-down forces in tide pools: test of a food chain model in an intertidal community. Ecological Monographs 71:187-217.

Table A1. Regression equations used to calculate animal biomass.

Species Equation R2 P N Range
          Size
Amphissa columbiana Bm = -0.19999 + 0.0362(sz) 0.823 0.0001 48 5-17 mm
Bittium eschrichtii Bm = -0.1031 + 0.0241(sz) 0.946 0.0001 16 6-12 mm
Calliostoma ligatum

Log(bm) = -6.2231 + 0.5356(sz)

- 0.0122(sz2)

0.890 0.0001 135 2-25 mm
Chitons Bm = -1.3880 + 0.1250(sz) 0.869 0.0001 15 6-37 mm
Hemigrapsus nudus Sqrt(bm) = -0.0293 + 0.0382(sz) 0.690 0.0001 62 0.6-11 mm
Idotea wosnesenskii Log(bm) = -6.1395 + 0.1559(sz) 0.616 0.0001 128 5-27 mm
Lepidochitona dentiens Bm = -0.0211 + 0.0058(sz) 0.525 0.0002 20 4-10 mm
Limpets >10mm Log(bm) = -4.7905 + 0.1885(sz) 0.916 0.0001 32 10-25 mm
Nucella emarginata Bm = -0.4351 + 0.0677(sz) 0.908 0.0001 15 6-18 mm
Pagurus samuelis Bm = -0.9067 + 0.1080(sz) 0.772 0.0002 11 10-35 mm
Pugettia producta

Log(bm) = -6.7241 + 0.6695(sz)

- 0.0165(sz2)

0.840 0.0001 56 3-15 mm
Searlesia dira Bm = -0.2153 + 0.0450(sz) 0.898 0.0001 19 3-21 mm
Strongylocentrotus purpuratus

Bm = 0.2692 - 0.1061(sz)

+ 0.0100(sz2)

0.997 0.0001 35 5-63 mm
Tectura scutum

Bm =1.0779 - 0.1376(sz)

+ 0.0051(sz)

0.847 0.0001 15 10-24 mm
Tegula funebralis Log(bm) = -7.1549 + 0.8993(sz) + 0.0368(sz2) + 0.0006(sz3) 0.992 0.0001 102 3-30 mm
Tonicella lineata Sqrt(bm) = 0.0875 + 0.0243(sz) 0.625 0.0001 78 0.5-33 mm
          Number of individuals
Lacuna marmorata Log(bm) = -4.2938 + 0.0141(no) 0.508 0.0001 50 1-350
Limpets >5 and <10 mm Sqrt(bm) = 0.1511 + 0.0347(no) 0.882 0.0001 86 1-22
Limpets <5 mm Log(bm) = -4.3429 + 0.0677(no) 0.571 0.0001 53 1-80
Littorina scutulata Bm = 0.0121 + 0.291(no) 0.888 0.0001 57 1-20
Pagurus hirsutiusculus Bm = -0.0162 + 0.0164(no) 0.986 0.0001 13 1-30

Notes: Biomass (in grams dry mass) was calculated from: size for large animals (>10 mm), or number for small (<10 mm), abundant animals. Animals were dried to constant mass at 60 ° C. Chitons include: Katharina tunicata, Mopalia muscosa, M. lignosa, M. ciliata. Limpets include: Lottia digitalis, L. strigatella, L. pelta. Data were transformed as necessary to meet assumptions of normality and homoscedasticity. Adjusted R2 values are presented for all polynomial regressions. Bm = biomass (g); sz = size (mm); no = number of animals; log = natural log; sqrt = square root.


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