Identification of Fine-Scale Marine Benthic Ecoclines by Multiple Parallel Ordination

Table 2

Recorded environmental variables: group affiliation, name, description, range, and mean (of raw, untransformed values).

Variable	Description	Range	Mean
DEM derived
Aspect_E	Eastness component of aspect	−1.00–1.00	0.10
Aspect_N	Northness component of aspect	−0.96–0.92	–0.35
BPI	Bathymetric position index	−1.52–1.34	–0.06
Depth [m]	Depth derived from DEM	35.8–93.2	58.6
Seabed_curv	Maximum curvature of the seabed (in any direction)	−0.011–0.042	0.005
Slope [deg]	The slope of the seabed	0.3–19.8	6.7
Current model
Current_bottom [m/s]	Maximum current speed at the bottom	0.026–0.077	0.049
Current_surface [m/s]	Maximum current speed at the ocean surface	0.061–0.091	0.068
Change_curr_bottom	The rate of instantaneous change of max bottom current	−1.71e-3–1.18e-3	1.96e-6
Change_curr_surface	The rate of instantaneous change of max surface current	−1.18e-3–3.61e-4	−1.92e-4
Direction_curr_E	Eastness component of the direction of the bottom current	−1.00–0.97	–0.47
Direction_curr_N	Northness component of the direction of the bottom current	−1.00–1.00	0.24
Particle-size
Mud content [%]	The silt-clay fraction of the sediment	8.4–77.2	55.6
Sed_kurt	Kurtosis of the sediment particle distribution	0.70–1.31	0.94
Sed_med [μm]	Median sediment particle-size	28.0–944.9	97.1
Sed_skew	Skewness of the sediment particle-size distribution	−0.78–0.36	0.09
Sed_sort	Sorting of the sediment particle-size distribution	4.2–8.6	5.8
Other variables
BMD [cm]	Biogenic mixing depth derived from sediment profile images	0.0–3.1	1.7
Penetration_depth [cm]	Penetration depth of SPI—a proxy for sediment shear strength	0.0–19.4	12.2
CN	Carbon-to-nitrogen-ratio (weight/weight)	7.9–19.3	11.5
TOC [%]	Percentage of total organic carbon	1.7–5.6	3.8
TN [%]	Percentage of organic nitrogen	0.12–0.63	0.34
VEAS_dist [m]	Distance from effluent of VEAS wastewater treatment plant	1143–2120	1640