patrickbdevaney/mia9 · Datasets at Hugging Face

text stringlengths 0 6.44k
and Brock 2006). The legislature also mandated public land protection agencies to focus on using
alternatives to fee simple acquisition. Since 2000, FF has protected more than 1.3 million acres
of water resources, environmentally sensitive lands, and parks (Department of Environmental
Protection [DEP] 2016). Many of these areas have been protected through less-than-fee
arrangements, involving purchase of conservation easements. Conservation easements allow
lands to stay in private ownership but legally restrict what activities can occur on the land. At the
64 • MICHAEL I. VOLK ET AL.
same time, the land stays on the local tax rolls and under private management. Figure 2.2 shows
conservation lands in Florida classified by date of protection based on the Florida Natural Areas
Inventory Florida Conservation Lands dataset. This data includes both public and private lands
that are either protected primarily for conservation or where conservation is an important activity
(e.g., various military installations across Florida).
Figure 2.2. Florida conservation lands and date of protection. Data Source: Florida Natural Areas Inventory
Florida Conservation Lands (Florida Natural Areas Inventory 2016)
Today Florida has a substantial acreage of its lands and waters in some kind of conservation
designation. Combined local, state, and federal conservation holdings equate to 29.4% of the
state, with 9,447,419 acres held in fee simple ownership and another 760,400 acres under
conservation easements (this figure is slightly higher if private conservation lands and lands in
FLORIDA LAND USE AND LAND COVER CHANGE IN THE PAST 100 YEARS • 65
private mitigation banks are included). These figures also include lands managed by the
Department of Defense (e.g., Eglin Air Force Base) for conservation benefits (667,200 acres)
and land under conservation easements held by the federal Natural Resources Conservation
Service (121,122 acres). Figure 2.3 shows conservation and managed lands in Florida classified
by managing entity.
Figure 2.3. Florida conservation lands and managing entities. Data Source: Florida Natural Areas Inventory
Florida Conservation Lands (Florida Natural Areas Inventory 2016).
While Florida’s history of conservation achievement has been impressive, it has not been
enough to prevent wholesale changes to and conversion of the Florida landscape – and its ecology
– on a massive scale, and additional conservation land is needed to effectively conserve the still
significantly, but quickly vanishing, natural resources that are still unprotected.
66 • MICHAEL I. VOLK ET AL.
Climate Change Impacts on Land Use and Land Cover To-Date
It is important to understand how changes in climate are already impacting land cover within the
state, as an indicator of what types of future changes may occur. Significant shifts in land cover
are already being seen in both upland and coastal areas as a result of sea level rise, precipitation,
and temperature change. Some of these are summarized here, though others are undoubtedly
occurring or have been documented.
Coastal Land Cover Changes along the Big Bend Coast
Florida’s Big Bend Coast, which stretches along the Gulf of Mexico from just north of Tampa to
south of Tallahassee, remains the least developed coastal region in the lower 48 states of the U.S.
The region’s forests, salt marshes, and near coastal marine environments are legendary for their
productivity due to a combination of factors including massive fresh water inputs from the
Suwannee River and several first-magnitude springs. That said, it has certainly not been spared
from human use, which is intensifying, while it is being rapidly inundated again by rising seas
(Williams et al. 1999; de Santis et al. 2007; Raabe and Stumpf 2016).
An understanding of the area’s geography is necessary to understand current changes. Like
most of Florida, the area is low in elevation and topographically nearly flat; the highest points
along the coast are the paleodune on Sea Horse Key and nearby Shell Mound, which started as a
dune but was enhanced by Amerindian engineers more than 1000 years ago — neither of those
peaks exceeds 20 meters in elevation. The flatness of the coastal region extends far out into the
Gulf of Mexico.
Another distinctive characteristic of the Big Bend region relates to the abundant water, both
fresh and somewhat salty. Tidal amplitudes in the Gulf of Mexico are small, less than half of
those in the Atlantic. Massive influxes of fresh water keep the near-shore salinities in Gulf water
at half of “normal” sea water. While all the rivers and spring runs moderate the Gulf’s salinity,
their waters do not deliver much sediment. Trapped sediments help build land, but the amount
deposited on coastal areas of the Big Bend is a small fraction of that carried by rivers.
The natural ecosystems along the Big Bend reflect the impacts of sea salt, as determined by
centimeters of elevational change and tempered by distance from the coast. As elevation rises
from the open water of the Gulf one crosses sea grass flats, some of which are exposed at
especially low tides, mud flats, and oyster bars. Salt marshes are next, often dominated by black
needle rush (Juncus roemerianus) with saltmarsh cordgrass (Spartina spp.) on the depositional
banks of meandering tidal streams. At slightly higher elevations, salt marsh shrubs flourish often
under the dying crowns of the red cedars (Juniperus virginiana) and cabbage palms (Sabal
palmetto) they replace as sea level rises. Healthy forested islands of cabbage palms and cedars
surrounded by salt marsh are next at elevations of 50-60 cm where inundation is only by the
highest of high tides as well as by storm surges, which can be several meters high. Inland and
slightly uphill from the coastal hammocks of cedar and palms there can be slash pine flatwoods
FLORIDA LAND USE AND LAND COVER CHANGE IN THE PAST 100 YEARS • 67
on sandy soils where fires are frequent or, more often, swamp forests referred to as hydric
hammocks (Vince et al., 1989). These long hydroperiod wetlands can have as many as 25 species
of canopy trees including several species of ash (Fraxinus spp.), oak (Quercus spp.), and elm
(Ulmus spp.), with only scattered cabbage palms.
Big Bend ecosystems have been shaped by humans since they arrived some 14,000 years ago.
For example, early as well as recent occupants harvested the bountiful shell and bony fish
(McCarthy 2006). While modern clam farms benefit from new technologies, farming the sea has
been underway for millennia, as indicated by archeological discoveries of massive fish weirs and
managed oyster bars. Less than a century ago, pencil slat and brush factories near Cedar Key
gobbled up thousands of red cedar and cabbage palm trees every month. Up until a few decades
ago when the furniture mills closed, hardwoods were harvested from the hydric hammocks. To
this day, stands of slash pine are clear-cut for pulp and saw timber, hunters seek deer, turkeys,
bear, and other wildlife throughout the region while crabbers, oyster harvesters, and fisherman
ply the coastal waters and up into the tidal creeks.
In addition to the direct effects of sea level rise, ecosystems in the Big Bend Region are being
influenced by the decreasing frequency of the hard freezes that set the northern limits to the
distributions of many plant species including mangrove trees (Williams et al. 2014). For reasons
that are not yet clear, no tree species can withstand both high salinity and cold freezes. This
means that where there are hard freezes, salt marshes predominate, whereas the coasts of warmer
areas typically support mangrove forests. Black mangrove (Avicennia germinans), the most
common species of mangrove tree in the region, can withstand super-high salinities but is killed
by freezing temperatures. The northern limit of black mangrove is currently about halfway up
the Big Bend Coast, but that limit continues to shift northwards as will be described in more
detail in the next section. This massive switch from marsh to forest has numerous implications
for the biota, biogeochemistry, and the effects of storm surges, which are blocked better by dense
forests than by low-growing herbaceous vegetation.
The other big change underway along the Big Bend Coast is also related to global change,
but is driven by Brazilian pepper, an invasive species described earlier in this chapter. Brazilian
pepper is top-killed by hard freezes but, unlike mangrove trees, re-sprouts afterwards. The fact
that it tolerates fairly high soil salinities allows it to proliferate where cabbage palms and cedar
trees are succumbing to salt stress (Ewe and Sternberg 2005). Because it can grow taller than the

and Brock 2006). The legislature also mandated public land protection agencies to focus on using

alternatives to fee simple acquisition. Since 2000, FF has protected more than 1.3 million acres

of water resources, environmentally sensitive lands, and parks (Department of Environmental

Protection [DEP] 2016). Many of these areas have been protected through less-than-fee

arrangements, involving purchase of conservation easements. Conservation easements allow

lands to stay in private ownership but legally restrict what activities can occur on the land. At the

64 • MICHAEL I. VOLK ET AL.

same time, the land stays on the local tax rolls and under private management. Figure 2.2 shows

conservation lands in Florida classified by date of protection based on the Florida Natural Areas

Inventory Florida Conservation Lands dataset. This data includes both public and private lands

that are either protected primarily for conservation or where conservation is an important activity

(e.g., various military installations across Florida).

Figure 2.2. Florida conservation lands and date of protection. Data Source: Florida Natural Areas Inventory

Florida Conservation Lands (Florida Natural Areas Inventory 2016)

Today Florida has a substantial acreage of its lands and waters in some kind of conservation

designation. Combined local, state, and federal conservation holdings equate to 29.4% of the

state, with 9,447,419 acres held in fee simple ownership and another 760,400 acres under

conservation easements (this figure is slightly higher if private conservation lands and lands in

FLORIDA LAND USE AND LAND COVER CHANGE IN THE PAST 100 YEARS • 65

private mitigation banks are included). These figures also include lands managed by the

Department of Defense (e.g., Eglin Air Force Base) for conservation benefits (667,200 acres)

and land under conservation easements held by the federal Natural Resources Conservation

Service (121,122 acres). Figure 2.3 shows conservation and managed lands in Florida classified

by managing entity.

Figure 2.3. Florida conservation lands and managing entities. Data Source: Florida Natural Areas Inventory

Florida Conservation Lands (Florida Natural Areas Inventory 2016).

While Florida’s history of conservation achievement has been impressive, it has not been

enough to prevent wholesale changes to and conversion of the Florida landscape – and its ecology

– on a massive scale, and additional conservation land is needed to effectively conserve the still

significantly, but quickly vanishing, natural resources that are still unprotected.

66 • MICHAEL I. VOLK ET AL.

Climate Change Impacts on Land Use and Land Cover To-Date

It is important to understand how changes in climate are already impacting land cover within the

state, as an indicator of what types of future changes may occur. Significant shifts in land cover

are already being seen in both upland and coastal areas as a result of sea level rise, precipitation,

and temperature change. Some of these are summarized here, though others are undoubtedly

occurring or have been documented.

Coastal Land Cover Changes along the Big Bend Coast

Florida’s Big Bend Coast, which stretches along the Gulf of Mexico from just north of Tampa to

south of Tallahassee, remains the least developed coastal region in the lower 48 states of the U.S.

The region’s forests, salt marshes, and near coastal marine environments are legendary for their

productivity due to a combination of factors including massive fresh water inputs from the

Suwannee River and several first-magnitude springs. That said, it has certainly not been spared

from human use, which is intensifying, while it is being rapidly inundated again by rising seas

(Williams et al. 1999; de Santis et al. 2007; Raabe and Stumpf 2016).

An understanding of the area’s geography is necessary to understand current changes. Like

most of Florida, the area is low in elevation and topographically nearly flat; the highest points

along the coast are the paleodune on Sea Horse Key and nearby Shell Mound, which started as a

dune but was enhanced by Amerindian engineers more than 1000 years ago — neither of those

peaks exceeds 20 meters in elevation. The flatness of the coastal region extends far out into the

Gulf of Mexico.

Another distinctive characteristic of the Big Bend region relates to the abundant water, both

fresh and somewhat salty. Tidal amplitudes in the Gulf of Mexico are small, less than half of

those in the Atlantic. Massive influxes of fresh water keep the near-shore salinities in Gulf water

at half of “normal” sea water. While all the rivers and spring runs moderate the Gulf’s salinity,

their waters do not deliver much sediment. Trapped sediments help build land, but the amount

deposited on coastal areas of the Big Bend is a small fraction of that carried by rivers.

The natural ecosystems along the Big Bend reflect the impacts of sea salt, as determined by

centimeters of elevational change and tempered by distance from the coast. As elevation rises

from the open water of the Gulf one crosses sea grass flats, some of which are exposed at

especially low tides, mud flats, and oyster bars. Salt marshes are next, often dominated by black

needle rush (Juncus roemerianus) with saltmarsh cordgrass (Spartina spp.) on the depositional

banks of meandering tidal streams. At slightly higher elevations, salt marsh shrubs flourish often

under the dying crowns of the red cedars (Juniperus virginiana) and cabbage palms (Sabal

palmetto) they replace as sea level rises. Healthy forested islands of cabbage palms and cedars

surrounded by salt marsh are next at elevations of 50-60 cm where inundation is only by the

highest of high tides as well as by storm surges, which can be several meters high. Inland and

slightly uphill from the coastal hammocks of cedar and palms there can be slash pine flatwoods

FLORIDA LAND USE AND LAND COVER CHANGE IN THE PAST 100 YEARS • 67

on sandy soils where fires are frequent or, more often, swamp forests referred to as hydric

hammocks (Vince et al., 1989). These long hydroperiod wetlands can have as many as 25 species

of canopy trees including several species of ash (Fraxinus spp.), oak (Quercus spp.), and elm

(Ulmus spp.), with only scattered cabbage palms.

Big Bend ecosystems have been shaped by humans since they arrived some 14,000 years ago.

For example, early as well as recent occupants harvested the bountiful shell and bony fish

(McCarthy 2006). While modern clam farms benefit from new technologies, farming the sea has

been underway for millennia, as indicated by archeological discoveries of massive fish weirs and

managed oyster bars. Less than a century ago, pencil slat and brush factories near Cedar Key

gobbled up thousands of red cedar and cabbage palm trees every month. Up until a few decades

ago when the furniture mills closed, hardwoods were harvested from the hydric hammocks. To

this day, stands of slash pine are clear-cut for pulp and saw timber, hunters seek deer, turkeys,

bear, and other wildlife throughout the region while crabbers, oyster harvesters, and fisherman

ply the coastal waters and up into the tidal creeks.

In addition to the direct effects of sea level rise, ecosystems in the Big Bend Region are being

influenced by the decreasing frequency of the hard freezes that set the northern limits to the

distributions of many plant species including mangrove trees (Williams et al. 2014). For reasons

that are not yet clear, no tree species can withstand both high salinity and cold freezes. This

means that where there are hard freezes, salt marshes predominate, whereas the coasts of warmer

areas typically support mangrove forests. Black mangrove (Avicennia germinans), the most

common species of mangrove tree in the region, can withstand super-high salinities but is killed

by freezing temperatures. The northern limit of black mangrove is currently about halfway up

the Big Bend Coast, but that limit continues to shift northwards as will be described in more

detail in the next section. This massive switch from marsh to forest has numerous implications

for the biota, biogeochemistry, and the effects of storm surges, which are blocked better by dense

forests than by low-growing herbaceous vegetation.

The other big change underway along the Big Bend Coast is also related to global change,

but is driven by Brazilian pepper, an invasive species described earlier in this chapter. Brazilian

pepper is top-killed by hard freezes but, unlike mangrove trees, re-sprouts afterwards. The fact

that it tolerates fairly high soil salinities allows it to proliferate where cabbage palms and cedar

trees are succumbing to salt stress (Ewe and Sternberg 2005). Because it can grow taller than the