Spatial gradient Age-related macular degeneration (AMD) 1 Bio-assessment 1 Cone-rod break (CRB) 1 Cost reduction 1 Dark adaptation (DA) 1 Dissolved oxygen 1 Ecology 1 Efficiency 1 Environmental change 1 Estuaries 1 Functional characteristics 1 Functional traits 1 Good environmental status 1 Longitudinal monitoring 1 Marine strategy framework directives 1 Nematoda 1 Nematode assemblages 1 Particle size 1 Particle size analysis 1 Phototransduction 1 Rod-intercept time (RIT) 1 Sado estuary 1 Sediment particle size 1 Spatial discrimination 1 Spatial gradients 1 Subretinal drusenoid deposits (SDD) 1 Taxonomic sufficiencies 1 Taxonomies 1 abundance 1