CARI Lakes and Wetlands Class Definitions
The table below provides definitions for the Lake and Wetland classes in the California Aquatic Resource Inventory (CARI).
|Beaches are narrow, sloping coastal habitats that are characterized by largely unvegetated sand or fine gravel that extends from MLLW or the upper end of the rocky intertidal zone up in elevation to the dune toe. Beaches are tidal habitats that are periodically inundated by the ocean and their substrate is commonly reworked by tidal flows, storm flows, ocean currents, and the wind. Dunes are not included in this category unless referring to sandy mounds that occur between MLLW and the modeled dune toe elevations.
|Dunes are coastal habitats characterized by sand and sandy soils that are formed into mounds or ridges by the wind. Dunes can be unvegetated or stabilized by vegetation. Due to the uniqueness of this habitat type, dunes can support a diverse and unique suite of plant, insect, and animal species. Both individual dunes and dune fields are included in this category.
|Eelgrass (Zostera marina and Z. pacifica) is an important ecological resource in nearshore open coast areas, shallow bays, and estuaries throughout coastal California. This specialized habitat consists of subtidal areas that support beds of eelgrass in their fine-grained bed substrate. Eelgrass can form underwater meadows of vegetation, contributing to the marine food web, filtering the water column, protecting the shoreline from erosion, and providing habitat for foraging, spawning, and shelter for many fish, invertebrates, and sea turtles.
|Fluvial channels are better known as riverine wetland habitat or sometimes rivers, streams, or creeks. They have unidirectional flow (e.g. not tidal) and transport freshwater, sediment, and nutrients through watersheds downstream to larger receiving water bodies. Fluvial channels can be natural or unnatural (e.g. ditches, canals), but always consist of defined bed and banks. Channels can be perennial, intermittent, or ephemeral.
|Forested Tidal Wetland
|Forested Tidal wetland area supports woody vegetation such as willows and alders. Most commonly this includes vegetated areas within bar-built estuaries and forested wetland areas open to the tides within the Sacramento-San Joaquin Delta.
|Irrigated areas purposefully have surface water added (e.g. sprinklers or flood irrigation) on a managed schedule to increase the soil moisture. Irrigation occurs primarily for agriculture, including growing crops or encouraging grass/herbaceous vegetation growth in pastures.
|Lake, Reservoir and associated vegetation
|These wetlands are characterized by areas of open water that are >2m deep and >8 ha in size. Natural features are called lakes, and unnatural features that are impounded behind dams are called reservoirs. Lakes and reservoirs typically have associated vegetation along the margins of the wetland that are hydrologically dependent on the open water. This vegetation can consist of tules, cattails, grasses, herbs/forbs, willows and other tree species, and shrubs such as coyote brush or mulefat.
|Managed and Muted Tidal Habitats
|Managed and Muted Tidal Habitats are composed of tidal wetland areas that have managed hydrology, including controls on the timing and/or amount of water delivered. These areas typically have reduced frequency and duration of inundation as compared to natural tidal habitats. Despite the controls, these areas typically still support a community of tidal wetland vegetation species.
|Playas are a wetland type that contains a shallow (<2m deep), seasonal or perennial body of sodic (alkaline) or saline water, typically runoff from the watershed. The wetland is nearly level, shallow, has very fine grained sediment (e.g. silts, clays) comprising the bed, and can be very large (up to many hundreds of acres in size). Vegetation is usually very sparse, only supported along the margins, and consists of salt-tolerant species.
|Ponds are estuarine features consisting of enclosed topographic basins (typically enclosed by berms or levees) that have regular, semi-regular, or at least periodic connection with estuarine water bodies. Water that enters the pond can be hypersaline, saline, or brackish. Ponds can hold surface water perennially or seasonally. Ponds typically do not have much vegetation cover across their fine-grained beds or in the water column. Any vegetation present typically occurs along the perimeter of feature and/or on the surrounding berm/levee.
|Pond and associated vegetation
|A type of depressional wetland that typically has perennial surface water present. A pond can be natural or unnatural, and is smaller than a lake or reservoir. It often supports areas of emergent, woody, herbaceous, or floating vegetation either in the pond (e.g. cattails, tules, duckweed, lily pads) and/or along its margins (e.g. sedges, rushes, willows, grasses). The associated vegetation is dependent upon the presence of the perennial surface water.
|Riverine Vegetation is directly associated with a riverine channel and is dependent upon the surface and shallow groundwater transported by the channel. Vegetation can be present in the active channel, on channel features such as bars, or on the banks and immediate margins of the channel. Vegetation can include emergent monocots such as cattails, grasses, herbs/forbs, sedges and rushes, shrubs, and tree species.
|Rocky shore habitats are areas of coarse grain size sediment (larger than sand) within the intertidal zone and splash/spray zone. These areas fall between marine and terrestrial habitats that support species adapted to alternating exposure of air and sea water. Rocky shore areas often are unvegetated, but can support pockets of vegetation in the interstitial spaces.
|Slope and Seep Wetlands
|Slope wetlands are flow-through groundwater-dominated wetlands inclusive of wet meadows, forested slopes, seeps, and springs. Slope refers to the unidirectional flow of the shallow groundwater or surface water that supports the wetland. Shallow groundwater supports the vegetation in slope wetlands, which can include sedges, rushes, grasses, herbs/forbs, vines, willows, and other deciduous and/or coniferous trees. Seeps and springs are typically smaller in size and have a point source (spring) or a zone (seep) of groundwater emerging into the root or to the surface, typically occurring at topographic breaks in slope or geologic unit contacts.
|Subtidal Vegetation are aquatic habitat areas that support aquatic vegetation on the bed surface or in the water column. These habitats are subject to tidal action, but the bed is never exposed. Eelgrass, which is a type subtidal vegetation, is mapped as a separate class.
|Subtidal water are aquatic habitat areas that are perennially covered with surface water, such as areas within the San Francisco Bay. The bed is primarily very fine sediment (e.g. silts, muds, clays) and is unvegetated. Tidal action is present, but the bed is never exposed. Also included are perennially underwater areas within bar-built estuaries such as the channel and its features.
|Tidal Flat and Marsh Panne
|Tidal flats are aquatic habitats that typically exist adjacent to subtidal water and tidal marsh areas. Flats are subject to tidal action, but are regularly exposed during low tides. Tidal flats have fine grained beds (e.g. silts, muds, clays) and provide foraging for shorebirds during low tide. Marsh pannes are also fine grained aquatic habitats that are subject to tidal action. They are unvegetated areas that typically exist within a well-vegetated marsh plain area. Pannes can be perennial or seasonal.
|Tidal marshes are wetlands that are fully or partially tidal for at least one month of the year, and experience periods of wetting and drying associated with the tides. Marshes may be hypersaline, saline, brackish, or even non-saline. Marshes may consist of their vegetated marsh plain, tidal channel network, smaller marsh pannes, potholes, hummocks and other habitat features. The tidal channels fully or partially dewater at low tide. Marshes can have levees/berms, culverts, and tide gate structures that control the hydrology of the marsh. Marsh vegetation can consist of pickleweed, spartina, salt grass, gumplant, tules, cattails, scirpus or other emergent monocots, based upon salinity.
|Vernal Pools are shallow, seasonal depressional wetlands that are underlain by an impervious material (e.g. a soil horizon, a clay layer, bedrock) that allows surface water to temporarily or seasonally pond and then dry through the spring/summer/fall. Vernal pools support a unique vegetation community, particularly specialized vernal pool endemic species, although many other native and non-native plants are typically present as well.