Codes and Definitions for the Biological Unit Database

WREC class (from MacKenzie & Banner, in preparation):

Es:	Salt swamp:	Salt swamps are treed or shrubby mineral ecosystems that occur in brackish lagoon, channel and estuary edges with occasional tidal flooding and waterlogged, slightly saline soils. Thickets of tall shrubs and trees tolerant of wet, slightly saline soils are typical. Soils are usually mineral though some sites may have a significant well-humified organic horizon.
Ed	Salt meadow:	Salt meadows are ecosystems dominated by tall forbs and graminoids that develop in the high intertidal and supratidal zones of estuaries where tidal flooding is less frequent than daily. These sites are flooded during higher high tides, storm events or during river flood. Soils are often waterlogged during portions of the growing season and are oligo- to eusaline mineral soils.
Em	Salt marsh:	A salt marsh is an intertidal ecosystem dominated by salt-tolerant emergent graminoids and succulents. They occur in the middle to upper tidal zones of estuaries where fresh water and salt water mix. Sites are alternately flooded and exposed daily. Elevationally banded surface patterns that reflect degree of tidal inundation are common.
Ew	Estuarine shallow water:
Et	Estuarine tidal flat:

Site Series (from MacKenzie & Banner, in preparation)

Site series are named by the common name of the dominant species (Table 5). More site series are presently being described and defined for coastal BC (MacKenzie, pers.comm.) and the codes for Site series units are not yet compiled to be included in this table. The groupings of the Site series into the more-general WREC class is included in Table 6.

Table 5 - Estuary Site Series Units. These are treated as equivalent to the species assemblages described in the marine - process - dominated Bio-band Units (Table 6).

WREC Class (code in parenthesis)	Site Association Name	Scientific name
ESTUARINE SWAMP (Es)
	Pacific crabapple - False lily-of-the-valley	Malus fusca - Maianthemum dilatatum
	Myrica gale - Bluejoint	Myrica gale - Calamagrostis canadensis
	Sitka willow - False lily-of-the-valley	Salix sitchensis - Maianthemum dilatatum
	Sitka spruce - Slough sedge	Picea sitchensis - Carex obnupta
	Sitka spruce - Pacific crabapple	Picea sitchensis - Malus fusca
ESTUARINE MEADOW (Ed)
	Nootka reedgrass	Calamagrostis nutkaensis
	Tufted hairgrass	Deschampsia cespitosa
	Tufted hairgrass - Douglas' aster	Deschampsia cespitosa - Aster subspicatus
	Cow parsnip - Silverweed	Heracleum lanatum - Potentilla anserina
	Dunegrass - Pacific hemlock-parsley	Leymus mollis - Conioselinum pacificum
ESTUARINE MARSHES(Em)
	Common orache	Atriplex patula
	Pond water-starwort - Flowering quillwort	Callitriche stagnalis - Lilaea scilloides
	Lyngby's sedge	Carex lyngbyei
	Seashore saltgrass - American glasswort	Distichlis spicata - Salicornia virginica
	Common spike-rush	Eleocharis palustris
	Sea milk-wort mudflat	Glaux maritima
	Arctic rush	Juncus arcticus
	Seaside plantain - Dwarf alkaligrass	Plantago maritima - Puccinellia pumila
	American glasswort	Salicornia virginica mudflat
	Seacoast bulrush	Scirpus maritimum
	American bulrush - Soft-stemmed bulrush	Scirpus americanus - Scirpus validus
	Canadian sand-spurry - Blue-green algae	Spergularia canadensis - Cyanophyta spp.
ESTUARINE SHALLOW WATER (Ew)	Widgeon-grass	Ruppia maritima
ESTUARINE TIDAL FLAT (Et)	None currently described. Bio-bands are currently used.

Bio-bands (after Searing & Frith, 1995):

Most of the bio-bands found in estuaries are equivalent for the banding described for other low wave exposure shorelines or estuaries throughout BC (Searing & Frith, 1995). However, a band has been added for the estuarine mapping to describe polygons which are bare of sessile macrobiota - the BRE, bare band. Because the estuary mapping is always verified by ground survey, the detail required to map biota which may not be visible from remote-sensed photos or video can be included. In the BRE (bare) band, observations on the ground may detect low cover of sessile biota or infauna in these bare-looking polygons. Species lists for all the observed biota and an associated percent cover estimate for each species, would appear in the plot data for field verification (see the Site Form and data attributes In Section 4.6).

Table 6 - Estuary Bio-band codes and description for marine-process-dominated elevations in the estuary. These are summary species assemblage codes are treated as equivalent to the Site Series Units (Table 5).

Bio-band Code	Colour Band Name	Colour	Description
VER	`Verrucaria'	Black or bare rock	Splash zone: marked by black encrusting lichen & blue-green algae. Generally only occurs on bedrock shoreline.
FUC	`Fucus'	Golden brown	Dominated by Fucus, includes B. glandula. upper intertidal.
BAR	Upper barnacle	Grey-white	Continuous band of B. glandula, upper intertidal.
BRE	Bare substrate	Bare substrate	No visible attached macrobiota. In-fauna (i.e. clams & worms) or holes of burrowing shrimp may be observed during ground verification.
OYS	Oyster	White	Abundance of Crassostrea. Only found in warm water areas Strait of Georgia, none north of Campbell R/ Desolation Sound.
BMU	Blue mussel	Dark blue-black	Dense beds of Mytilus trossulus (blue mussel).
ULV	`Ulva'	Bright green	Ulva/'Ulvaria' blade greens and Enteromorpha-type filamentous greens. May appear as thick patches or as green haze of small plants.
SBR	Soft browns	Brown	Sargassum, and large bladed Laminaria spp. - the unstalked blade browns, which are seen in the lower intertidal and nearshore subtidal.
ZOS	`Zostera'	Dark green	Eelgrass, (Zostera marina and introduced spp. Z. japonica) fine sediment, may extend slightly upslope into intertidal. Often heavily encrusted with epiphytic blade red.