Appendix D. Details on the variables selected in the optimal models predicting arthropod assemblages (the cross-validatory fit for each model is presented at the top).
Models were constrained to use only vegetation structure data, only environmental data, or both, or used floristic composition. See Appendix B for more information on variable names. Floristic effects were studied in three different ways; only the variables selected in the characteristic species group approach are presented. For the other floristic approaches, only the cross-validatory fit is relevant.
To help judging the correspondence between plant species composition and other local predictors, also the individual plant species composition was placed in the dependent position and its predictive models were calculated (final part of the table).
Structure |
Environment |
Structure + Environment |
Floristic composition Characteristic spec. groups: |
|
Spiders |
8.35 % HalfDensity Level Temp. MaxHeight Temp. VarHeight Open+Litter Cover |
8.00 % Spring moisture Organic matter Sand content pH N-NO3 N-NH4 Mineral N |
10.19 % HalfDensity Level Temp. MaxHeight Temp. VarHeight Temp. RatioHeight Herb+Moss Cover Herb Cover Spring moisture pH N-NO3 K conc. Nitrification deg. |
12.14 % Phragmitetea Parvo-Caricetea Calthion Arrhenatheretalia Arrhenatherion Koel.-Corynephoretea Corynephoretalia Trif.-Festucetalia Sedo-Cerastion Calluno-Ulicetea Individual species: 9.67 % Community type: 8.70 % |
Grass-hoppers |
9.71 % Peak Height Peak Density HalfDensity Level Vert. DensityShape Temp. MeanHeight Temp. VarHeight Spatial VarHeight Moss Cover |
15.52 % Spring moisture Organic matter Sand content N-NO3 P-PO4 Nitrification deg. |
18.46 % Temp. RatioHeight Spatial VarHeight Open+Litter Cover Spring moisture Organic matter Sand content |
29.20 % Artemisietea Molinietalia Corynephoretalia Trif.-Festucetalia Sedo-Cerastion Calluno-Ulicetea Nardetea Individual species: 15.90 % Community type: 17.98 % |
Groundbeetles |
8.80 % Peak Density HalfDensity Level Vert. DensityShape Temp. MaxHeight Temp. VarHeight Temp. RatioHeight Herb+Moss Cover Herb Cover Open+Litter Cover |
10.71 % Spring moisture Sand content pH N-NO3 Mineral N Nitrification deg. |
14.31 % Peak Density Vert. DensityShape Temp. MeanHeight Temp. VarHeight Temp. RatioHeight HerbMoss Cover Herb Cover Open+Litter+Moss Spring moisture Sand content N-NO3 Mineral N Nitrification deg. Sun duration |
14.20 % Phragmitetea Parvo-Caricetea Artemisietea Calthion Arrhenatherion Koel.-Corynephoretea Corynephoretalia Trif.-Festucetalia Sedo-Cerastion Calluno-Ulicetea Individual species: 15.25 % Community type: 16.02 % |
Weevils |
7.69 % Peak Height Vert DensityShape Temp. MaxHeight Temp. MeanHeight Temp. VarHeight Temp. RatioHeight Herb+Moss Cover Herb Cover Open+Litter Cover |
8.08 % Spring moisture Sand content pH N-NO3 N-NH4 Mineral N |
11.75 % Peak Density HalfDensity Level Temp. MaxHeight Temp. MeanHeight Temp. VarHeight Temp. RatioHeight Spatial VarHeight Herb Cover Open+Litter Cover Spring moisture Organic matter pH N-NO3 N-NH4 Mineral N P-PO4 K conc. Nitrification deg. |
11.66 % Phragmitetea Plantaginetea Filipenduletea Galio-Urticetea Artemisietea Mol.-Arrhenatheretea Molinietalia Calthion Arrhenatheretalia Koel.-Corynephoretea Corynephoretalia Thero-Airion Sedo-Cerastion Calluno-Ulicetea Individual species: 15.11 % Community type: 12.58 % |
Hoppers |
9.08 % Peak Height Peak Density Vert. DensityShape Temp. VarHeight Temp. RatioHeight Spatial VarHeight Herb+Moss Cover Herb Cover |
12.66 % Summer moisture Sand content N-NH4 P-PO4 K conc. |
13.00 % Vert. DensityShape Temp. VarHeight Open+Litter Cover pH N-NH4 P-PO4 |
24.41 % Parvo-Caricetea Plantaginetea Filipenduletea Galio-Urticetea Artemisietea Molinietalia Calthion Arrhenatheretalia Corynephoretalia Thero-Airion Calluno-Ulicetea Individual species: 18.29 % Community type: 24.94 % |
Hover-flies |
2.63 % Temp.RatioHeight Moss Cover Open Cover Litter Cover Open+Litter Cover |
4.73 % Spring moisture Summer moisture K conc. Temp. index |
5.37 % HalfDensity Level Vert. DensityShape Temp. MaxHeight Herb+Moss Cover Open Cover Open+Litter+Moss Spring moisture pH N-NO3 P-PO4 Nitrification deg. Sun duration Temp. index |
5.57 % Phragmitetea Parvo-Caricetea Galio-Urticetea Cynosurion Individual species: 3.28 % Community type: 3.99 % |
Bees |
1.86 % Peak Density Temp. MaxHeight Temp. MeanHeight Temp. VarHeight Open+Litter+Moss |
1.67 % Spring moisture Organic matter N-NO3 Sun duration |
1.99% Temp. VarHeight Temp. RatioHeight Open+Litter Cover Open+Litter+Moss pH Nitrification deg. Temp. index. |
3.30 % Parvo-Caricetea Filipenduletea Artemisietea Molinietalia Arrhenatheretalia Cynosurion Corynephoretalia Trif.-Festucetalia Sedo-Cerastion Calluno-Ulicetea Nardetea Individual species: 2.36 % Community type: 2.13 % |
As background information, the best models predicting individual plant species composition are given below. |
||||
Structure |
Environment |
Structure + Env. |
Characteristic spec. groups:† |
|
Plant species comp. Individual species |
10.01 % Peak Height HalfDensity Level Vert. DensityShape Temp. MaxHeight Temp. MeanHeight Temp. VarHeight Temp. RatioHeight Temp. VarHeight Herb+Moss Cover Herb Cover Moss Cover |
11.43 % Spring moisture Organic matter pH N-NO3 N-NH4 Mineral N P-PO4 K conc. Nitrification |
14.27% Temp. MaxHeight Temp. MeanHeight Temp. VarHeight Temp. RatioHeight Vert. DensityShape Herb Cover Moss Cover Open+Litter Cover Spring moisture Sand content pH N-NO3 N-NH4 P-PO4 Nitrification deg. |
23.12 % Phragmitetea Parvo-Caricetea Plantaginetea Filipenduletea Galio-Urticetea Artemisietea Mol.-Arrhenatheretea Arrhenatheretalia Corynephoretalia Trif.-Festucetalia Thero-Airion Sedo-Cerastion Calluno-Ulicetea Community type: 22.55 % |
† Of all 20 "characteristic species groups" used in this study, the species characteristic of the Alopecurion were never selected in any of the optimal models and this species group therefore does not appear in the table.