seaweed

Supported seaweed identification

Record the narrowest identification justified by diagnostic evidence, retaining uncertainty and the reference used.

1. What observations establish this as seaweed rather than seagrass, another aquatic plant or a non-algal organism? boundary
2. Which taxonomic reference, identification method and dated evidence support the assigned name, authority and identifiers? provenance

Recorded biological unit

Define whether observations describe one thallus, a fragment, a population or an assemblage with multiple taxa.

1. What physical or sampling boundary defines the seaweed entity represented by this record? definition
2. Could overlapping thalli, connected growth or multiple taxa make an apparent individual or single-species patch misleading? boundary

Diagnostic thallus structures

Describe branching, texture, blades, attachment structures or other features where present without imposing a vascular-plant anatomy.

1. Which thallus structures, textures and branching patterns are present and useful for identification? definition
2. Is the thallus attached, naturally free-living or recently detached, and what evidence supports that interpretation? measurement

Life-stage evidence

Record observable growth and reproductive features while leaving unobservable life-cycle phases unresolved.

1. Which life-cycle stage and reproductive condition are supported by the observed structures or laboratory evidence? definition
2. How have defined thallus dimensions, new tissue or reproductive structures changed across dated observations? measurement

Occupied habitat

Describe the conditions actually experienced by attached or drifting seaweed at a documented place and time.

1. What substrate, depth, tidal exposure and water movement characterise this occurrence? measurement
2. What measured temperature, salinity and light conditions accompany the observation, and over what period? measurement

Local status and associations

Record evidence for local origin or establishment alongside observed habitat provision, grazing and competition.

1. What dated regional evidence supports classification as native, introduced, transient or of uncertain origin? provenance
2. Which organisms use, graze, colonise or compete with this seaweed, and which effects have actually been observed? measurement

Observed damage and vitality

Document pigmentation, tissue loss, fouling and decomposition relative to an appropriate taxon and life-stage baseline.

1. What proportion of the thallus shows tissue loss, altered pigmentation, fouling or decomposition? measurement
2. What evidence distinguishes ordinary seasonal change from grazing, physical damage, disease or environmental stress? provenance

Comparable population observations

Track cover, density or biomass while preserving sampling area, method, season and uncertainty.

1. What cover, density or biomass was measured, using which sampling design and wet or dry mass basis? measurement
2. Do repeat observations support expansion, decline or seasonal turnover after accounting for sampling and detectability differences? measurement

Suitable propagation and transfer

Record the evidence needed to select culture conditions, propagation material and a destination.

1. What evidence supports the proposed propagation method and environmental conditions for this taxon and life stage? action
2. What source locality, associated organisms and establishment risks must be assessed before moving this seaweed? action

Evidence-based intervention

Specify the biological evidence, permissions and follow-up observations required for harvesting, control or retention.

1. How would the proposed timing, cutting location or removal extent affect regeneration, reproduction and associated organisms? action
2. Which current local permissions, conservation assessments and monitoring criteria govern whether and how the intervention proceeds? action

Check these first

Recalled without web access and unsourced; every item is a lead to verify.

• Seaweed denotes multiple evolutionary lineages, not a species, population or individual; no single native range, conservation assessment or species identifier applies.
• Life cycles, reproductive structures and life-stage differences require species-level treatment; a generic sexual-dimorphism description would be misleading.
• Check species identity, accepted nomenclature and geographic origin before assigning composition ranges, conservation status or food-safety requirements.

1. Which of these check these first hold for the sense of seaweed this model covers, and on what evidence? provenance

Kinds and varieties

Recalled without web access and unsourced; every item is a lead to verify.

• Red seaweeds (Rhodophyta)
• Green seaweeds (principally within Chlorophyta)
• Brown seaweeds (Phaeophyceae)

1. Which of these kinds and varieties hold for the sense of seaweed this model covers, and on what evidence? provenance

Identifiers and schemes

Recalled without web access and unsourced; every item is a lead to verify.

• Scientific taxonomic name - Genus species, with nomenclatural authority where applicable - Identifies a constituent species; seaweed itself has no single accepted binomial or taxonomic authority.
• GBIF taxon key - Numeric identifier - Applies to individual taxonomic records, not to seaweed as one natural taxon.
• NCBI Taxonomy ID - Numeric taxid - Identifies constituent taxa represented in NCBI Taxonomy.
• WoRMS AphiaID - Numeric identifier - Identifies marine taxonomic records in the World Register of Marine Species.

1. Which of these identifiers and schemes hold for the sense of seaweed this model covers, and on what evidence? provenance

Real-world use

Recalled without web access and unsourced; every item is a lead to verify.

• Food, including nori, kombu and wakame
• Production of agar, carrageenan and alginates
• Fertilizers and agricultural biostimulants
• Animal feed ingredients
• Research and cultivation for nutrient removal from water

1. Which of these real-world use hold for the sense of seaweed this model covers, and on what evidence? provenance

Failure modes and hazards

Recalled without web access and unsourced; every item is a lead to verify.

• Some edible species can contain high iodine concentrations; composition varies by species, environment and processing.
• Seaweeds can accumulate contaminants, including arsenic and other potentially harmful elements.
• Introduced species can spread invasively and alter local habitats.
• Large stranded accumulations can decompose, deplete oxygen locally and release hydrogen sulfide.
• Marine heatwaves, disease, grazing and excessive harvesting can damage seaweed populations and habitats.

1. Which of these failure modes and hazards hold for the sense of seaweed this model covers, and on what evidence? provenance

Regional variation

Recalled without web access and unsourced; every item is a lead to verify.

• Large kelp forests are especially characteristic of cool, nutrient-rich coastal waters, while other seaweed assemblages occur in tropical seas.
• Species composition and shore zonation vary with temperature, salinity, tidal exposure, light and wave action.
• Food names and uses differ regionally: nori, kombu and wakame refer to distinct seaweed products rather than interchangeable names for all seaweeds.

1. Which of these regional variation hold for the sense of seaweed this model covers, and on what evidence? provenance

Neighbouring kinds and how to tell them apart

Recalled without web access and unsourced; every item is a lead to verify.

• Algae - Algae also includes microscopic and freshwater forms; seaweed usually denotes macroscopic marine forms.
• Kelp - Kelps are brown seaweeds of the order Laminariales; most seaweeds are not kelps.
• Seagrass - Seagrasses are marine flowering plants with true roots, stems and leaves; seaweeds are algae.
• Phytoplankton - Phytoplankton are photosynthetic organisms living suspended in water, mostly microscopic; floating seaweed remains macroalgal material.
• Edible seaweed - Edible seaweed is a food-use subset or harvested product; the broader category includes organisms unsuitable for consumption.

1. Which of these neighbouring kinds and how to tell them apart hold for the sense of seaweed this model covers, and on what evidence? provenance