An introduction to the plants, soils, and hydrology of California - - PDF document

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An introduction to the plants, soils, and hydrology

• f California tidal marshes

John Callaway Department of Environmental Science University of San Francisco

What’s happened to California’s wetlands?

What percentage of California’s wetlands have been lost?

• a. 10 %
• b. 50 %
• c. 75 %
• d. 90 %
• e. 99 %

Introduciton to Ecology and Regulation of Tidal Wetlands in Central California and the San Francisco Bay August 17, 2005 Coastal Training Program Workshop Elkhorn Slough National Estuarine Research Reserve (NERR) San Francisco Bay NERR 1/10

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100,000,000 200,000,000 300,000,000 400,000,000

Wetland area (acres)

United States Alaska Lower 48 1980 early 1800's

(Dahl 1990) size of Calif.

Wetland Loss in the United States

5,000,000 10,000,000 15,000,000 20,000,000 25,000,000

Wetland area (acres)

FL LA TX MN MI NC

State

Wetland Loss by State

1980 early 1800's

(Dahl 1990)

5,000,000 10,000,000 15,000,000 20,000,000 25,000,000

Wetland area (acres)

CA OR WA FL LA TX MN MI NC

State

1980 early 1800's

(Dahl 1990)

Wetland Loss by State

SF Bay Wetlands Past and Present

• ca. 1850
• ca. 1998

(from SFEI)

A Quick Introduction to Tidal Marshes

Hydrology

tides freshwater inputs

Soils

lack of oxygen salinity

Vegetation

spatial patterns of distribution on a variety of scales adaptations common species

Understanding Tidal Marsh Hydrology

Hydroperiod

frequency of inundation duration of inundation depth of inundation

Critical hydrological factors

tides freshwater inputs

Introduciton to Ecology and Regulation of Tidal Wetlands in Central California and the San Francisco Bay August 17, 2005 Coastal Training Program Workshop Elkhorn Slough National Estuarine Research Reserve (NERR) San Francisco Bay NERR 2/10

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Tides

Mixed, semi-diurnal tides on Pacific Coast

two highs and lows each day different heights

Elevation relative to the tides determines

inundation regime

Other coasts have different tidal patterns

low marsh mid-marsh plain high marsh - upland transition

Tidal Variation across the Marsh

regularly inundated rarely inundated

Importance of Tidal Creeks

• deliver water, sediment

and nutrients to marsh

• flush salts from soils
• more important in salt

marshes than in brackish and freshwater marshes

Freshwater Inputs

Large-scale variation up the estuary Similar patterns up larger drainages Finer-scale pattern within a marsh, and

associated with any local freshwater inputs

VERY DIFFERENT than other US tidal

marshes (mediterranean climate)

Introduciton to Ecology and Regulation of Tidal Wetlands in Central California and the San Francisco Bay August 17, 2005 Coastal Training Program Workshop Elkhorn Slough National Estuarine Research Reserve (NERR) San Francisco Bay NERR 3/10

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Spatial Variation in FW Inputs

• greatest input from Delta
• significant local inputs at

many local rivers/creeks, including:

• Napa R.
• Petaluma R.
• Alameda Creek
• Coyote Creek

low marsh mid-marsh plain high marsh - upland transition

Salinity Variation across Salt and Brackish Marshes

more regular salinity more variable salinity (higher in summer and lower in winter)

Tidal Marsh Soils: Key Characteristics

Fine texture (lots of clay and silt) Poorly drained

low oxygen levels (often no oxygen in soil) low redox status

High organic content Moderate pH Unusual biogeochemistry (anaerobic conditions)

Tidal Marsh Soil Biogeochemistry

Driven by anaerobic processes Mix of aerobic and anaerobic zones in the soil Sequence of oxidation-reduction reactions

O2, NO3-, Mn4+, Fe3+, SO42-, CO2 (oxidized forms) H20, N2, Mn2+, Fe2+, S2-, CH4 (reduced forms)

Unusual nutrient dynamics

especially nitrogen

Tidal Marsh Soils

Varying patterns across the marsh:

saturation/inundation salinity

Seasonal patterns as well, especially salinity

low marsh mid-marsh plain high marsh - upland transition

Spatial Variation in Soil Factors

lower soil oxygen less variable salt higher soil oxygen more variable salt

Introduciton to Ecology and Regulation of Tidal Wetlands in Central California and the San Francisco Bay August 17, 2005 Coastal Training Program Workshop Elkhorn Slough National Estuarine Research Reserve (NERR) San Francisco Bay NERR 4/10

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Plants: Key Factors Affecting Distribution

Inundation (anaerobiosis, oxidation/reduction) Salinity (both summer stress and winter/spring

lows for germination)

Nutrients Competition History

Spatial and Temporal Variability

Spatial scales of variability

estuarine-wide scale drainage scale within wetland scale

Temporal scales of variability

climate change inter-annual variation seasonal changes (recruitment)

Tidal Marsh Plant Distributions

Salt Marsh Brackish Marsh Freshwater Marsh Remember transitional-upland species!!

low marsh

Spartina foliosa

mid-marsh plain

Salicornia virginica

high marsh - upland transition

Salicornia virginica Frankenia salina Distichlis spicata Grindelia stricta Leymus triticoides

Simplified Salt Marsh Plant Zonation

Zonation is similar in brackish marshes, but less obvious, and even less obvious in freshwater marshes. (PWA and Faber 2005)

Plant Zonation

Plant Adaptations

Anaerobiosis

physical adaptations

aerenchyma and adventitious roots

physiological adaptations

Salinity

secrete salt

• ther physiological adaptations

Introduciton to Ecology and Regulation of Tidal Wetlands in Central California and the San Francisco Bay August 17, 2005 Coastal Training Program Workshop Elkhorn Slough National Estuarine Research Reserve (NERR) San Francisco Bay NERR 5/10

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Salt Marsh Plants

Spartina foliosa (cordgrass) Salicornia virginica (pickleweed) Jaumea carnosa (jaumea) Distichlis spicata (saltgrass) Frankenia salina (alkali heath) Cuscuta salina (salt marsh dodder) Atriplex triangularis (spearscale, fat-hen) Triglochin maritima (seaside arrow-grass) Limonium californicum (salt marsh rosemary, sea lavender) Grindelia stricta (gumplant) Leymus triticoides (creeping wildrye)

Introduciton to Ecology and Regulation of Tidal Wetlands in Central California and the San Francisco Bay August 17, 2005 Coastal Training Program Workshop Elkhorn Slough National Estuarine Research Reserve (NERR) San Francisco Bay NERR 6/10

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Spartina foliosa Distichlis spicata Frankenia salina Limonium californicum Grindelia stricta

Introduciton to Ecology and Regulation of Tidal Wetlands in Central California and the San Francisco Bay August 17, 2005 Coastal Training Program Workshop Elkhorn Slough National Estuarine Research Reserve (NERR) San Francisco Bay NERR 7/10

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Brackish Marsh Plants

• Scirpus maritimus (NOW: Bolboschoenus maritimus)
• Scirpus californicus (NOW: Schoenoplectus californicus) (Calif. tule)
• Scirpus acutus (NOW: Schoenoplectus acutus) (hardstem bulrush, tule)
• Scirpus americanus (NOW: Schoenoplectus americanus)
• Typha angustifolia (narrowleaf cattail)
• Typha latifolia (broadleaf cattail)
• Juncus spp. (rush)
• Salicornia virginica
• Distichlis spicata
• Jaumea carnosa
• Atriplex triangularis
• Baccharis pilularis (coyote brush)
• Rosa californica (California rose)

Scirpus maritimus Scirpus californicus Scirpus acutus Scirpus americanus

Freshwater Marsh Plants

• Typha angustifolia
• Typha latifolia
• Scirpus acutus
• Scirpus californicus
• Juncus spp.
• Polygonum spp.
• Sagittaria spp.
• Rubus spp.
• Salix spp.
• Lilaeopsis masonii
• Mimulus guttatus
• Lycopus americanus
• Calystegia sepium
• AND MANY OTHER SPECIES!!

Introduciton to Ecology and Regulation of Tidal Wetlands in Central California and the San Francisco Bay August 17, 2005 Coastal Training Program Workshop Elkhorn Slough National Estuarine Research Reserve (NERR) San Francisco Bay NERR 8/10

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Typha angustifolia Typha latifolia

Rare Tidal Marsh Plants

Cordylanthus maritimus subsp. palustris Cordylanthus mollis supsp. mollis Cirsium hydrophilum Aster lentus Lathryus jepsonii var. jepsonii Lilaeopsis masonii AND MORE…

Non-Native Tidal Marsh Plants

Spartina alterniflora (and hybrids with S. foliosa) Lepidium latifolium (peppergrass) Eichhornia crassipes (water hyacinth) Cotula coronopifolia (brass buttons) Polypogon monspeliensis (rabbit’s-foot grass) Rumex crispus (curly dock) Phragmites australis (common reed) AND MORE…

Plant Summary

Mix of physical and biological factors that affect

plant distributions, including inundation and salinity

Diversity is reduced with higher salinity Diversity is higher in the upper marsh Creeks have strong role in salt marsh plant

distribution, not so prominent in brackish and freshwater tidal marshes

Upper marsh-transitional areas have many rare

species, as well as many non-native invasives

Introduciton to Ecology and Regulation of Tidal Wetlands in Central California and the San Francisco Bay August 17, 2005 Coastal Training Program Workshop Elkhorn Slough National Estuarine Research Reserve (NERR) San Francisco Bay NERR 9/10

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Acknowledgments

CalPhotos: Plants (for photos)

http://elib.cs.berkeley.edu/photos/flora/

Philip Williams and Phyllis Faber (for reading

• n SF Bay wetland restoration)

Joy Zedler (additional readings)

Introduciton to Ecology and Regulation of Tidal Wetlands in Central California and the San Francisco Bay August 17, 2005 Coastal Training Program Workshop Elkhorn Slough National Estuarine Research Reserve (NERR) San Francisco Bay NERR 10/10