North Carolina Vegetationand Ecosystems :North Carolina Vegetationand Ecosystems NCST 2000
Introduction to North Carolina Studies
Fall 2008
Dr. Tom Shields
Some Basic Concepts :Some Basic Concepts
Food Chains in Ecosystems :Food Chains in Ecosystems Producers are consumed by consumers (herbivores or primary consumers), and they are in turn eaten by secondary consumers, etc. This linear relationship is called a food chain.
plants herbivore carnivore
A food web is currently the more common metaphor.
Succession :Succession In a disturbed area, such as in an abandoned field or a burnt out forest, an ecosystem will have a series of dominant plant communities:
1 year—crabgrass
2 years—horseweed
3 years—broomsedge
5-15 years—pines
25-50 years—pines and hardwoods
150 years—oak/hickory “climax” forest
The general model of succession used throughout the United States was developed in the 1930s by Dwight Billings and other biologists who studied abandoned agricultural fields in the Piedmont. Thus, the model fits the Piedmont very well, but changes in some ways for other ecosystems, such as the longleaf pine forest (below).
Other Pictures of Succession :Other Pictures of Succession
Succession Beyond Forests :Succession Beyond Forests As with farming or forest fire, Hurricane Isabel’s opening of a breach on Hatteras Island in September 2003 and people’s refilling the breach left land without its natural vegetative cover. Pictures from Hurricane Isabel at .
The Hatteras Example (cont.) :The Hatteras Example (cont.) "Hurricane Isabel: Three Years Later,” by Kristin Davis (The Virginian-Pilot 17 Sept. 2006: Y1+)
Less than a month after [Hurricane Isabel], the $7.5 million project of pumping sand and water from the Ocracoke-Hatteras ferry channel began. It took 16 days. Within two months, human life had largely returned to normal.
That wasn’t the case with the environment, even though ecological systems tend to be resilient . . . . Recovery can be slow.
Zac Long [an ecologist with the University of North Carolina’s Institute of Marine Sciences in Morehead City] and field assistant Katy Frank, an undergraduate student at UNC, started studying the difference nearly three years had made. They began on the beaches, taking samples of clams, mole crabs and other creatures using aluminum cores about 15 centimeters in diameter and depth. . . .
They compared their beachside samples along the former inlet to other beach areas. . . .
[T]he ocean side seems to have recovered on its own. It was good news. Bad news waited on the other side of N.C. 12 . . . .
They sampled – 75 cores per site, just like at the beach – and came up empty-handed. . . .
There was something else. The sounds along the Outer Banks have gently sloping surfaces. “We expected to be able to walk 25 to 50 meters out. At 15 meters, we were in over our heads. It drops off,” Long said.
So why have the beaches recovered while the sound has not?
“I think it more reflects the energy of the system,” Long wrote in an e-mail. “The beach has the constant waves and long-shore currents” that probably restored the sediments and animal life. The sound lacks that energy. The plants, he explained, probably have not come back because it is nearly impossible for seeds to take root on that windy, barren stretch of land. . . .
North Carolina Vegetation and Ecosystems :North Carolina Vegetation and Ecosystems
Physiographic Regions of NC :Physiographic Regions of NC Coastal Plain
Elev: 0-200 ft
Sedimentary rock, sandy soils (marine deposits)
Piedmont
Elev: 200-2500 ft
Red soil is remnant of the metamorphic mountains
Appalachian highlands
Elev: 2500-6000 ft
Metamorphic rock (400 million years old)
Coastal Waters :Coastal Waters
Coastal Oceans :Coastal Oceans Atlantic Ocean over continental shelf
Zone offshore of barrier islands out to edge of continental shelf (salinity = 35 parts per thousand)
Fishes: various tunas, dolphin, jacks, marlin, king mackerel, bluefish, groupers, seatrouts, drums, croakers, etc. Amberjack Yellowfin Tuna and Dolphinfish
Outer Coastal Plain :Outer Coastal Plain
Outer Coastal Plain :Outer Coastal Plain Estuary System
Two main native vegetation types:
Maritime Forests
Coastal Marshes
Estuaries :Estuaries Where fresh water from rivers meets with seawater from coastal ocean (salinity = 0 to 35 parts per thousand).
Fishes: spots, croakers, seatrouts, drums, spanish mackerel.
Blue crab and shrimp are important commercial invertebrate fisheries (a)Croaker; (b) Spot; (c) Fishing for Spot; (d) Molting Blue Crab; (e) Separating Shrimp from Bycatch (a) (b) (c) (e) (d)
Where Do Estuaries Begin and End? :Where Do Estuaries Begin and End? Essentially along the same line that divides the Inner Coastal Plain form the Outer Coastal Plain. However, going inland even along the Outer Coastal Plain, the estuary system runs only as far as where the water is brackish, that is, where there is a mix of fresh and salt water.
Albemarle-Pamlico Estuary System :Albemarle-Pamlico Estuary System The Albemarle-Pamlico Sounds region is the second largest estuarine system in the United States, second only to the Chesapeake Bay. Composed of seven sounds—the Albemarle, Currituck, Croatan, Pamlico, Bogue, Core and Roanoke—and five major river basins, as well as beaches, marshes and bottomland forests.
Estuary systems include not just the estuaries themselves, but the rivers and oceans that feed fresh and salt water into them.
Estuarine Food Webs :Estuarine Food Webs Before humans:
Seagrasses common
Oysters abundant
Water filtered every 3 days
Low run-off from land After fishing and farming:
Seagrasses less common
Oysters depleted
Sediments and nutrients
Anoxia (absence of oxygen) and eutrophication (over nourishment of water)
Coastal Marshes :Coastal Marshes Protected area behind barrier beaches.
Two types:
Salt Marshes
Freshwater Marshes
95% of fish and shellfish taken by commercial and recreations fishermen in North Carolina depend in some way on coastal marshes and other parts of the estuary system Pea Island National Wildlife Refuge
Salt Marshes :Salt Marshes Regularly flooded salt marshes found primarily southwest of Beaufort Inlet
Irregularly flooded salt marshes found north of Beaufort Inlet
Dominant species—cordgrass, blackneedle rush. Pea Island Bogue Banks Bogue Banks/Beaufort Inlet near Morehead City, Beaufort, Atlantic Beach, Emerald Isle, etc., is the dividing point between the northern and southern Outer Banks. There are some important differences in the ecosystems of the two based on their topography.
Freshwater Marshes :Freshwater Marshes Found in the upper Currituck Sound, along the fringes of the Albemarle Sound, and along the Cape Fear River near Wilmington
Dominant species—bulrush, cattail, saw grass, big cordgrass
Soil is predominantly peaty and continually waterlogged with fresh to slightly brackish water 1990 1969 Northwest River off of Currituck Sound
Maritime Forests :Maritime Forests Climax forest type varies:
Divided at approximately Bogue Banks
Southern—dominated by live oakwith local variations
North—intermixture of speciescharacteristic of inland forests(e.g., beech, pine, hickory, hophornbeam)
Relicts of hardwood forestsduring periods of lower sealevel. Bogue Banks
Inner Coastal Plain :Inner Coastal Plain
Inner Coastal Plain :Inner Coastal Plain Longleaf Pine Savannas formerly dominant
Mixed hardwood/pine forests
Pine plantations now dominant
Floodplain swamp forests
Longleaf Pine Savanna :Longleaf Pine Savanna 80' to 100' tall. The crown has tufts of needles at the ends of stout twigs.
Dark green needles 8" to 18" long.
Most commonly found on well-drained soils.
Longleaf pine grows in open to moderately dense stands with various grasses and shrubs in the understory.
Requires fire periodically to burn non-fire resistant competing trees and maintain the open understory.
Changes in Longleaf Pine Forests :Changes in Longleaf Pine Forests Until the nineteenth century, longleaf pine dominated the ecosystems of the coastal plains in the southeast.
Two main reasons for its loss:
Over harvesting for naval stores (materials used in boat building), especially tar and pitch derived from pine resin.
Fire suppression policies that, while well intentioned to prevent wild fires, prevented the burns that were necessary to maintain longleaf pine ecosystems.
Floodplain Forests :Floodplain Forests Cypress, black gum, water oak, willow oak, hackberry
ECU campus vegetation (we are in a floodplain)
Coastal Flatwoods :Coastal Flatwoods Pine-oak forest vegetation
Loblolly pine and upland oaks are dominant on the uplands
Water tupelo, swamp blackgum, sweetgum, and oaks are dominant on the bottom lands
Human-Planted Vegetation :Human-Planted Vegetation Pine Plantation Coastal Plains Agriculture
Piedmont :Piedmont
Piedmont :Piedmont Deciduous forests
Where most of NC’s population lives
Agriculture
Hydropower and Industry
Deciduous Forests :Deciduous Forests Climax Vegetation
Red oak
Hickory
Maple
Yellow poplar
(refer back to succession in earlier slides)
Animal Life
White tail deer
Insects
Fall Line :Fall Line From the Fall line west, there are few natural lakes and most water is fast moving.
The change in topography also changes the types of ecosystems found.
Reservoirs and Dams :Reservoirs and Dams Human activity, such as the creation of dams and surface reservoirs for flood control and to provide water for growing populations, has changed the ecosystems of the Piedmont.
Natural Communities Fragmented :Natural Communities Fragmented Most Piedmont climax forest has disappeared:
Introduced species taking over (e.g., Kudzu vine)
Agriculture
Urbanization
Forest Areas in North Carolina :Source: Will McDow, Kris Coracini and Dan Whittle. Standing Tall: A New Path for North Carolina’s Private Forests. New York: Environmental Defense Fund, 2006. . Forest Areas in North Carolina
The Politics of Forests :The Politics of Forests “Report Urges Effort to Save Shrinking N.C. Forests,” by Tim Whitmire (The Virginian-Pilot 14 Sept. 2006: Y1+).
A property tax break for private owners of forested land who commit to conservation is one of the best ways to stem an estimated 100,000 acre annual loss of private forest land in North Carolina, an environmental group says in a report being released today.
According to Raleigh based Environmental Defense, the annual loss is roughly the size of the city of Durham. . . .
[Will] McDow and others from Environmental Defense are lobbying for the General Assembly to expand a law that allows forest land being used for timber production to be taxed at a lower rate.
The law, passed in the early 1970s, allows land that is producing agricultural, timber and other products to be taxed based on the value of its present use – instead of for its “highest and best use,” which often is its development value. In the report [“Standing Tall”], Environmental Defense says it believes the law “is out of date and should be revamped to provide tax relief to landowners who manage for wildlife and other conservation benefits.”
Many county officials, however, say they would oppose such a change.
The present law “is supposed to encourage and enable farmers to make a living in production of either timber or farm or horticultural products,” said Paul Meyer, assistant general counsel for the Raleigh-based North Carolina Association of County Commissioners. . . .
Broadening the tax break would also cut property tax revenue for often cash strapped counties, opponents said. . . .
Forest Loss, 1990-2002 :Forest Loss, 1990-2002 Source: Will McDow, Kris Coracini and Dan Whittle. Standing Tall: A New Path for North Carolina’s Private Forests. New York: Environmental Defense Fund, 2006. .
Pre-Historical Human Effects :Pre-Historical Human Effects Even though we think of Piedmont forests, many areas of the Piedmont were open prairies, either through wildfire, native animals grazing (such as deer, elk, etc.), or by Native Americans purposely set fire.
There are current efforts to restore some Piedmont areas to prairie.
Mountains :Mountains
Mountains :Mountains Mountain Balds
Spruce/Fir Forests
Mesic Forests
Cove Forests
Mountain Bogs and Fens
Mountain Streams
Mountain Bald :Mountain Bald Producers
Grasses, sedges, forbs,* shrubs, trees
Herbivores
Rabbits, insects, deer, cattle
Carnivores
Wolves, foxes
May have been created by burning by Native Americans and continued to be kept clear by European settlers
* A broad-leaved herb other than a grass, especially one growing in a field, prairie, or meadow.
Spruce/Fir (Boreal) Forests :Spruce/Fir (Boreal) Forests High mountain areas above 5500 ft
Red spruce (Picea rubens) and frasier fir (Abies fraseri) are dominant producers
Changes have occurred due to logging, hunting
Air pollution (acid rain) is a current problem, which can cause increased susceptibility to the Balsam Woolly Adelgid, an introduced insect pest
Mesic Forest :Mesic Forest Mesic—moderately moist
Usually in coves and on gentle slopes
Dominant vegetation
American Beech,
Red maple,
White pine,
Red oak,
Rhododendron,
Mountain laurel
American Chestnut (formerly dominant)
Chesnut Blight :Chestnut blight – Endothia parasitica Original range of American Chestnut Chesnut Blight American Chestnut was once an important tree in deciduous forests is USA
Dominant in community (40 % of trees), before blight
The parasitic fungus Endothia parasitica was imported by accident in nursery stock from Asia in NYC in 1900
The parasite kills tree by girdling 2-10 years later
Began killing trees in NC in 1920, all were gone by 1953
Cove Forests :Cove Forests Dominant Vegetation
Carolina Hemlock
Canadian Hemlock
Yellow Popular
High humidity, low light
Logging has made this community type rare in NC
Mountain Bogs, Fens :Mountain Bogs, Fens Dominant Vegetation:
Sphagnum moss
Alder
Red Maple
Rare wetland types in mountains
Mountain Streams :Mountain Streams Streams: Headwaters of rivers, 1st order (high current velocity)
Trout fishing
Endangered fish and mussel habitat Spotfin Chub,
Freshwater Mussel
Impact of Human Occupation :Impact of Human Occupation Clear-cutting for logging, farmlands, and pasturelands
Most logging had occurred by 1900’s
Mining
TVA Hydropower
Tourism
Another Example of Ecosystem Change :Another Example of Ecosystem Change Populations of this herbivore are increasing due to absence of natural predators and growth of agriculture.