Make your own free website on Tripod.com

Restoration Ecology - Week 6 & 7

Natural Communities of Southern Florida

I. PLANT COMMUNITIES OF SOUTHERN FLORIDA
A. Community Types
1. pine flatwood & dry prairie
2. pine rockland
3. hammocks
4. scrub
5. beach strand
6. swamp
7. mixed swamp
8. freshwater marsh & wet prairie
9. mangrove & coastal prairies
10. salt marsh
11. sea grass beds
B. Upland Communties I - Pine Flatwoods & Dry Prairies
1. Physical Features
a. Distribution
i. low flat topography, relatively poorly-drained, acidic sandy soils, sometimes underlain by organic matter
ii. most extensive terrestrial ecosystem in Florida, occur throughout the se coastal plain, occupy 50% of Florida's land area. Most extensive community in south Florida except for freshwater marsh, i.e. the Everglades
b. Physical Attributes - low relief, flat, low runoff
c. Soils - poorly drained, fine-textured sands, low clay om, low CEC, often contain a spodic horizon and sometimes a clay hardpan
d. Hydrology - Poor permeability results in standing water, litter decreases evaporation
2. Composition
a. Physiognomy - open overstory of pine, an extensive shrub layer and a variable often sparse herbaceous layer.
b.Canopy dominated by slash pine (Pinus elliottii var. densa) from tens of trees to 5,000+ per hectare.
c. Shrub composition and size
i. varies considerably, often discontinuous or multi-layered
ii. species include:
Hypericum fasciculatum (St. John's wort) add
Ilex glabra (gallberry)
Lyonia spp. (staggerbush)
Quercus spp. (oaks)
Serenoa repens (saw palmetto)
d. Herb layer
i. may be sparse or absent
ii. species include:
Andropogon virginicus (broomsedge)
Aristida stricta (wiregrass)
Coreopsis leavenworthii (tickseed)
e. Exotics
Melaleuca quinquenervia (melaleuca)
Schinus terebinthifolius (Brazilian pepper)
3. Ecological Processes
a. Fire
i. s. Fla. Slash pine is among the most fire tolerant pines, exceeded in tolerance only by long-leaf pine, grass-stage very fire resistant
ii. saw palmetto and wire grass highly flammable, promote fire
iii. cutthroat grass, broom sedge and wire grass do not flower without fire
iv. ideal fire frequency is once every 4 to 7 years; range managers recommend 2-year burn cycle
v. effects of fire (From Ewel et al.)
release mineral elements
increase insolation
create dead organic matter
stimulate increase in net primary production
release seeds and alter seed beds
reduce competition
stimulate vegetative reproduction, flowering and fruiting
influence succession rate and direction
increase forage available for herbivores
regulate yield of mast species, e.g. running oak
regulate insect populations (food for birds)
control mosaic pattern of vegetation
elimiante pathogens
stimulate mycorrhizal growth
C. Upland Communities II - Pine Rocklands
1. Introduction - "... we pursued our way through through a pine-barren, the ground being formed of coral rocks jutting out in sharp points like oysterbeds, which caused us great suffering by cutting through our boots and lacerating our feet at every step. It was certainly the most dreary and pandemonium region I ever visited; nothing but barren wastes where no grateful verdure quickened, and no generous plant took root - it was intolerable-excruciating. (Army Surgeon J.R. Motte, describing a trek to Long Pine Key 24 April 1838.
2. Physical Features
a.Distribution
i. outside ENP less than 2% of original pine rocklands remain and only three sites exceed 50 ha
ii. southern Florida (Dade, Broward, Collier and Monroe Counties).
iii. upland areas of extreme southern Florida underlain by limestones. Most of the rocklands have been cleared for housing and agriculture.
b. Physical Attributes
i. upland rock outcrops, usually with little relief, may be marked with solution features, banana holes (e.g.)
c. Geology and Soils
i. underlain by Miami, Key Largo and Tamiami Formations
ii. soils are shallow with high organic content. Plants often establish in organic matter trapped between solution features. pH of this material is circumneutral.
iii. shallow depressions in the rock contain fine, reddish-brown sandy loam, which are slightly acidic (pH 6 - 6.5) and have less than 10% organic matter. The name "Redlands" is derived from this soil type.
d. Hydrology - well-drained due to limestone solution features, higher pinelands seldom flood, lower pinelands adjacent to wet prairies may remain inundated for several months of the year
3. Composition
a. Physiognomy - relative open overstory of pine, a variable shrub layer and a variable herbaceous layer.
b. Canopy composition, size and density
i. dominated by slash pine (Pinus elliottii var. densa)
ii. density - ca. 500 trees per hectare.
c. Subcanopy
i rarely developed but may occur where fire has been suppressed
ii. species include live oak, poison wood, wild tamarind, and silver thatch palm
d. Shrub composition and size
i. varies considerably, open canopy and little soil development makes conditions harsh. More than 90 species have been recorded in subcanopy. Most of these are tropical.
ii. species include (bold species occur in all three rockland types):
Bursera simarouba (gumbo limbo) near hammocks
Cocothrinax argenta (silver thatch palm)
Dipholis salicifolia (willow bustic)
Dodonea viscosa (varnish leaf)
Ficus citrifolia (short-leaf fig)
Guettarda scabra (rough velvet seed) Lantana involucrata (wild lantana)
Lysiloma latiliqua (wild tamarind) near hammocks
Sabal palmetto (cabbage palm)
Serenoa repens (saw palmetto)
e. Herb layer
i. may be sparse or diverse, more than 250 herb species occur in rocklands, with more than half restricted to rocklands
ii. species include:
Anemia adiantifolia (pine fern)
Cassia derringiana
Crossopetalum ilicifolium (Christmas berry)
Crotalaria pumila (rattlebox)
Jacquemontia curtissii
Melanthera parvifolia (melanthera)
Zamia integrifolia (coontie)
f. Related communities
g. Exotics
Albizzia lebbeck (Mother-in-law's tongue)
Melaleuca quinquenervia (melaleuca)
Schinus terebinthifolius (Brazilian pepper)
Neyraudia reynaudiana (silk reed)
Pennisetum purpureum (Napier grass)
4. Ecological Processes
a. Fire
ii. fires usually burn only at the surface and do not enter the sparse
ii. open canopy allows rapid drying of litter
iii. hardwood shrubs and palms experience little mortality due to fire
iv. pineland herbs grow rapidly and reproduce following fire, several species flower infrequently except in burned areas
v. ideal fire frequency is once every 2-3 to 10-15 years
b. Succession
i. fire maintains species composition of pine rocklands
ii. in the absence of fire, hardwood species generally invade. Pines do not regenerate in their own shade
iii. successional changes lead to changes in the soil. Organic matter accumulates, shading increases, soil moisture increases and resistance to fires increases
iv. successional Patterns - hammock species increase in the absence of fire, species include Metopium toxiferum, Swietenia mahogon, Bursera simarouba, and Dipholis salicifolia
D. Upland Communities III - Hammocks
1. Introduction (Definitions)
a. Working definition - tropical hardwood hammocks are broad-leaved, evergreen forests with a closed canopy
b. Classification
i. Topographic
low hammocks
high hammocks
ii. Moisture regime
xeric
mesic
hydric
iii. Compositional
tropical
temperate
iv. canopy dominats
oak hammock
cabbage palm hammock
2. Physical Features
a. Distribution
i. often found on higher ground (more resistant) than surrounding area
ii. successional phases of pine flatwoods, scrub, pine rocklands and beach strand vegetation
b. Physical Attributes
i. usually flat, but do occur on ridges
ii. topography often irregular due to solution features
c. Geology and Soils
i. iropical hammocks - underlain by limestones - Miami, Key Largo and Tamiami, Anastasia and Ft. Thompson Formations
ii. oak hammocks are underlain by entisols or spodosols
iii. soils are shallow with high organic content but often with a well-developed humus layer. Plants often establish in organic matter trapped between solution features. pH of this material is circumneuatrlal.
d. Hydrology
i. well-drained due to limestone solution features when occuring on limestone. Moderately to poorly drained on sand and poorly drained when derived from swamp soils
3. Composition
a. Physiognomy - closed canopy of evergreenm broadleaf species
b. Canopy dominants -
i. sometimes single species, e.g., oak, gumbo limbo, poison wood
ii. Composition variable, species include:
Bursera simarouba (gumbo limbo)
Coccoloba diversifolia (pigeon plum)
Dipholis salicifolia (willow bustic)
Ficus aurea (strangler fig)
Lysiloma latiliqua (wild tamarind)
Mastichodendron foetidissimum (mastic)
Metopium toxiferum (poison wood)
Piscidia piscipula (Jamaica Dogwood)
Quercus virginiana (live oak)
Sabal palmetto (cabbage palm)
c. Subcanopy
Ateramnus lucidus (crabwood)
Chyrsophyllum oliviforme (satinleaf)
Exothea paniculata (inkwood)
Ilex cassine (dahoon holly)
Magnolia virginiana (sweet bay)
Persea borbonia (red bay)
Sabal palmetto (cabbage palm)
Simarouba glauca (paradise tree)
d. Shrub composition and size
Ardisia escallanoides (marl berry)
Eugenia axillaris (white stopper)
Krugiodendron ferrugineum (black ironwood)
Myrsine guinensis (myrsine)
Pyschotria nervosa (wild coffee)
Randia aculeata (whiteindigo berry)
e. Herb layer
Lasciasis divaricata (wild bamboo)
Nephrolepsis exaltata (Boston fern)
f. Vines - often very abundant, especially in disturbed sites
Pisonia aculeata (Devil's claw)
Toxicodendron radicans (poison ivy)
Chiococca alba (snowberry)
g. Epiphytes - often abundant
Encyclia tampensis (Butterfly orchid)
Guzmania monostachia (guzmania)
Peperomia obtusifolia (peperomia)
Phlebodium aureum (golden polyplody)
Polypodium polypodiodes (resurrection fern)
Tillandsia fasciculata (cardinal air plant)
Tillandsia utriculata (urn-shaped air plant)
Vittaria lineatis (shoestring fern)
h. Related communities
i. exotics
Ardisia solanacea (shoebutton ardisia)
Carica papaya (papaya)
Dioscorea bulbifera (yam)
Jasminum spp. (jasmine)
Schinus terebinthifolius (Brazilian pepper)
4. Ecological Processes
a. Fire - hammocks are relatively fire proof as long as the water table remains within a few feet of the ground surface during the dry season
a. Succession
i. fire maintains the species compositiopn of pine rocklands
ii. in the absence of fire, hardwood species generally invade. Pines do not regenerate in their own shade
iii. successional changes lead to changes in the soil. Organic matter accumulates, shading increases, soil moisture increases and resistance to fires increases
c. Successional Patterns
i. hammock species increase in the absence of fire
ii. species include - Metopium toxiferum, Swietenia mahogoni and Bursera simarouba, Dipholis salicifolia
E. Upland Communitues IV - Beach Strand and Dunes
1. Introduction (Definitions)
a. Florida has 1900 km of coastline, excluding the Keys
b. 1200 km of coastline is sandy with well-developed barrier islands
c. Sandy shores are high energy shores - low energy shores dominated by mangroves or salt marshes
2. Physical Features
a. Distribution - high energy coastlines
b. Physical Attributes
i. sloping shore lines
ii. barrier Islands - linear islands of sand than form parallel to the shore
iii. harsh physical conditions
wind
waves
salt spray - wind pruning
iv. unstable - jetties
v. zonation
upper beach and foredune
dune front (strand)
back dune
c. Geology and Soils
i. northern Florida beaches composed of quartz sands. Southern beaches composed of quartz and calcium carbonate.
ii. quartz comes from Appalachians in SE US. Coastal plain reivers bring little sediment.
iii. sediments of modern beaches come from reworked offshore deposits rather than directly from source areas.
iv. calcium carbonate increases toward the south:
Jacksonville - 10%
Miami - 40%
Cape Florida - 100%
d. Hydrology
i. extremely well-drained
3. Composition
a. Physiognomy
i. foredune - vine, grass, spiny herbs
ii. dune front - stunted shrubs, grasses
iii. back dune - shrubs changing to hammocks depending on age and protection
iv. Species include
b. vine
Canavalia rosea (seaside bean)
Ipomoea pes-caprae (railroad vine)
c. grass
Distichilis spicata (saltgrass)
Helianthus debilis (Beach sunflower)
Uniola paniculata (sea oats) - growth and tillering stimulated by burial
d. prickly
Cenchrus tribulodes (sand spur)
Cnidoscolus stimulosa (beach nettle)
Opuntia compressa (prickly pear)
Yucca aloifolia (Spanish bayonet)
e. dune front
Coccoloba uvifera (sea grape)
Mallotonia gnaphaloides (sea lavendar)
Scaevola plumeiri (half-eaten flower)
Serenoa repens (saw palmetto) may be salt sensitive
Suriana maritima (Bay cedar)
f. back dune - hammock species
g. Related communities
h. exotics
Casurina equisetifolia (Australian pine)
Scaevola taccada
Scinus terebinthifolius (Brazilian pepper)
4. Ecological Processes
a. Fire - unknown
b. Succession
i. hammock species increase in the absence of fire
ii. species include - Metopium toxiferum, Swietenia mahogoni and Bursera simarouba, Dipholis salicifolia
c. Hurricanes
F. Upland Communities V: Scrub
1. Introduction
a. Introduction - "nothing could be more sterile than the soil; and these tracts are, in fact, concealed deserts, as they are too poor to admit cultivation, andafford nothing that is fit, even for the browsing of cattle." Simmons 1822
b. Definition - scrub is xeromorphic vegetation, dominated by a layer of evergree oaks or rosemary with or without a pine overstory.
2. Physical Features
a. Distribution - Old Dunes
b. Geology and Soils - all entisols, often Quartzipsammnets
c. Hydrology - extremely well-drained
3. Composition
a. Physiognomy - evergreen, open canopy
b. Canopy composition, size and density
i. Scrub dominated by Pinus clausa or Quercus spp.
ii. Scrubby flatwoods dominated by Pinus elliottii
c. Subcanopy and shrub
Quercus myrtifolia (Myrtle oak)
Quercus chapmanii (Chapman's oak)
Quercus geminata (Scrub live oak)
Ceratiola ericoides (Rosemary)
Serenoa repens (Saw palmetto)
Lyonia ferruginea (Feterbush)
d. Herbs and lowshrubs
Licania michauxii (Gopher apple)
Rhynchospora megalocarpa (Scrub sedge)
Cladonia spp. (Lichen)
e. exotics
Schinus terebinthifolius (Brazilian pepper)
4. Ecological Processes
a. Fire - maintained by intense, infrequent fires
i. scrub (20-70 year cycle)
ii. scrubby flatwoods (3-15 year cycle)
b. Succession - hammock species increase in the absence of fire

G. Wetland Communities I - Swamps
1. Definitions
a. Swamps - forested wetlands
b. Marshes - dominated by graminoids
2. Stillwater swamps
a. Slash pine - wet prairies
b. Bay heads
c. Cypress heads
d. Cypress strand
e. Cypress savanna
f. Mixed hardwood
g. Melalueca
h. Hydric hammock
i. Single species (pop ash, willow)
3. Physical Features
a. Distribution - still compromise more than 10% of Florida's land area
b. Physical Attributes
i. hydroperiod -few species can tolerate flooded soil, low oxygen and high levels of iron, manganese, and hydrogen sulfide
ii. fire frequency - reduces organic matter accumulation, delays succession
iii. organic Matter accumulation
iv. source of water
c. Geology and Soils
i. geology varibale but requires an impermeable layer
ii. often associated with histosols and alfisols (glossaqualfs)
d. Hydrology
i. hydroperiod key to explaining difference in swamps
ii. once established cypress is one of the most flood tolerant species
3. Composition
a. physiognomy
i. medium to large trees
ii. canopy usually open but may be closed
b. Canopy species
Acer rubrum (red maple)
Fraxinus caroliniana (pop ash)
Magnolia virginiana (sweet bay)
Persea borbonia (red bay)
Pinus elliottii (slash pine)
Roystonea elata (royal palm)
Salix caroliniana (carolina willow)
Taxodium distichum (bald cypress)
c. Shrubs
Aceolorraphe wrightii (Everglades palm)
Cephalanthus occidentalis (button bush)
Chrysobalanus icaco (coco plum)
Ilex cassine (dahoon holly)
Myrica cerifera (wax myrtle)
d. Vines
Ipomea alba (moon vine)
Mikania scandens (hemp weed)
Sarcostemma clausum (white vine)
Smilax bona-nox (green brier)
Toxicondenron radicans (poison ivy)
Vitis rotundifolia (muscadine grape)
e. Herbs
Osmunda regalis (royal fern)
Blechnum serrulatum (swamp fern)
Ludwigia peruviana (primrose willow)
Peltandra virginica (green arum)
Saururus cernuus (Lizard's tail)
f. Epiphytes
Encyclia tampensis (butterfly orchid)
Epidendrum nocturnum (night-blooming orchid)
Guzmania monostachia (guzmania)
Peperomia obtusifolia (peperomia)
Phlebodium aureum (golden polyplody)
Polypodium polypodiodes (resurrection fern)
Tillandsia fasciculata (cardinal air plant)
Tillandsia pruinosa (fuzzy-wuzzy air plant)
Tillandsia utriculata (urn-shaped air plant)
Vittaria lineatis (shoestring fern)
g. Exotics
Melaleuca quinquenervia (melaleuca)
Schinus terebinthifolius (Brazilian pepper)

4. Ecological Processes
a. Fire
i. common particulary where hydroperiod is short
ii. severe burns - willow swamps
iii. cypress - resistant to fire
b. Succession
i. related communities include - marshes, hammocks, wet prairies and open water
H. Wetland Communities II - Marshes and Wet Prairies
1. Introduction and Definitions
a. Marshes - wetlands dominated by emergent, herbaceous plants, tree cover less than 33%, and significant organic matter accumulation
b. Wet Prairies - shorter hydroperiod, depth of lfooding is less, little or no organic matter accumulation, fire frequency is greater
c. Classification
i. cattail marsh
ii. sawgrass marsh
iii. sawgrass prairie
iv. wet prairie
v. flag marsh
2. Physical Features
a. Distribution
i. before development and drainage (100 years ago) 60% of Florida's surface was wetlands. Now they occupy 15-20 percent. Marshes make up about 1/3 of all wetlands in Florida.
ii. major marshes in southern Florida include the Everglades, Taylor Slough, Loxahatchee slough. Fisheating Creek and the Big Cypress.
b. Physical Attributes
i. topography and elevation determine distribution of marshes
ii. well-developed in southern Florida due to the flat topography and poor drainage. Coastal ridges act as natural barriers to drainage.
iii. rainfall exceeds potential evapotranspiration, particulary along the coast. Less pronounced along the Gulf Coast.
c. Geology and Soils
i. geology - much of Florida is underlain by permeable limestone or sand.
ii. soils - marsh soils are histosols, wet prairies occur on sands and marls
iii. periphyton - calcareous green and blue-green algae that precipitate calcareous marl in freshwater habitats. Greens associated with peat. Blue-greens with marls. Primary producer and integral part of the food chain.
d. Hydrology
i marshes - hydroperiod of 7 to 12 months per year with 50 cm of water
ii. wet prairies - hydroperiod of 2 to 6 months per year with 25 cm of water
iii. marshes occur where:
surficial deposits are impermeable
water table intersects the land surface, e.g., Everglades
marsh is hydrologically connected to a river
3. Composition
a. physiognomy - largely herbs, few shrubs and fewer trees. No epiphytes. Vines rare.
b. emergent trees
Pinus elliottii (slash pine)
Salix caroliniana (willow)
Taxodium distichum (bald cypress)
c. Shrubs
Ludwigia octovalis (swamp primrose)
Cephalanthus occidentalis (buttonbush)
Ludwigia peruviana (swamp primrose)
Myrica cerifera (wax myrtle)
d. Herbs
Cladium jamicensis (saw grass)
Dischromena colorata (white-topped sedge)
Eleocharis cellulosa (spike rush)
Hypericum fasciculataum (St. John's wort)
Nymphaea odorata (white water lily)
Panicum hemitomon (Maidencane)
Pontedaria lanceolata (pickerel weed)
Rhynchospora tracyi (beak rush)
Sagittaria latifolia (arrowhead)
Thalia geniculata (alligator flag)
Typha domingensis (cattali)
Utricularia spp. (bladderworts)
e. Exotics
Melaleuca quiquenervia (Melaleuca)
Schinus teribenthifolius (Brazilian pepper)
4. Ecological Processes
a. Fire - limits invasion of woody species. The color of Everglades peat is due to burning.
b. Succession - related communities include hardwood and willow swamps, cypress swamps, cypress savannas and pine flatwoods.


I. Intertidal Communities I - Mangroves
1. Definitions and Introduction
a. Mangroves - from a Portuguese word for tree (mangue and English word for a stand of trees (grove)
b. Used in two ways
i. type of tree growing in estuarine environments
ii. community of plants growing in estuarine environments - synonyms include tidal forest, tidal swamp, mangrove community, mangrove ecosystem, mangal and mangrove swamps
2. Physical Features
a. Distribution
i. tropical
ii. 90% of the mangroves in Florida are located in Dade, Collier, Lee and Monroe Counties
iii. northern limits are Ponce de Leon Inlet on Atlantic Coast and Cedar Key on the Gulf
b. Physical Attributes
i. climate - do not occur where annual temp is below 19o C (66oF), as climatic stress increases plant stature decreases, hurricane prone areas also have reduced strature
ii. salt water - flacultative halophytes, but are usually out-competed in freshwater environments
iii. water fluctuation - disperses propagules, transports nutrients and removes hydrogen sulfide, mangroves best developed where tidal fluctuations are great or where there is a broad, shallow bays with seasonal freshwater run-off (e.g., Everglades)
iv. runof of terrestrial nutrients
v. substrate and wave energy - flourish in depositional environments with low enrgy
3.. Composition
a. Dominants
i. Avicennia germinans - characterized by pneutmatophores (2-20 cm above the soil), can rreach a height of 20 m, propagules are lima-bean shaped, flowers in spring and summer
ii. Rhizophora mangle - characterized by prop roots, may reach 25 m in height, propagules are pencil shaped, flowers generally in summer and spring but can flower throughout the year, small reserve of leaf buds
iii. Laguncularia racemosa - tree to 15 m, propagules are small diamond shaped, flowers in spring and early summer
iv. Conocarpus erectus - mangrove associate, tree to 14 m, not viviparous
b. Exotics
Schinus terebinthifolius
Colubrina asiatica
Thespesia populnea
c. Zonation
i. Red - Black - Buttonwood (Davis 1943), White occurs sporadically in open, irregularly flooded areas
ii. Mangrove species can grow in all zones (Rabinowitz (1975)
iii. Black mangrove survives better in strongly reducing environments than does red mangrove (Thibodeau and Nickerson 1986)
4. Ecological Processes
a. Succession - steady-state cyclical or catastrophic climax
J. Intertidal Communities II - Salt Marsh
1. Definitions - intertidal communities dominated by non-woody, salt tolerant plants
2. Physical Features
a. Distribution - cover ca. 170,000 ha in Florida
b. Physical Attributes
i. low wave energy
ii. high tidal flow
iii. low mangrove cover
3. Composition
a. dominants
Batis maritima (saltwort)
Borrichia fructescens (sea oxeye)
Distichilis spicata (salt grass)
Juncus roemerianus (black rush)
Salicornia virginiaca (glasswort)
Sesuvium portulacastrum (sea purselane)
Spartina alterniflora (smooth cord grass)
Spartina patens (salt meadow cordgrass)
b. Zonation - distinct but poorly understood
c. exotics
Colubrina asiatica
Schinus terbenthifolius
4. Ecological Processes
a. Succession - steady-state cyclical or catastrophic climax, often replaced by mangrove species
K. Marine Communities I - Sea Grass Beds
1. Definitions - Sea grasses - not true grasses
2. Physical Features
a. Distribution
i. 10,000 km2 in Gulf of Mexico, more than 75% occur in Florida
ii. 5,500 km2 occur in Florida Bay and surrounding waters
iii. Cover 80% of the botom between Cape Sable, North Biscayne Bay and Dry Tortugas
b. Physical Attributes - not found on high energy sandy shores
3. Composition
a. Vascular plants
Thalassia testudinum (turtle grass - Hydrocharitaceae) - long, ribbon like leaves 4-12 mm wide and 10-35 cm long. most important species
Syringonium filiforme (manatee grass - Cymodoceaceae) - leaves 1 mm in diameter to 50 cm long
Haludole wrightii (shoal grass - Cymodoceaceae) blades 1-3 mm wide and 10-20 cm long, early colonizer of disturbed sites
Halophila engelmannii (sea grass - Hydrocharitaceae)
b. Green Algae
Halimeda
Udotea
Penicellus
Rhipocephalus
c. Coralline red Algae