Ecological Restoration - Tarleton State University

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Transcript Ecological Restoration - Tarleton State University

Figure 1.4 The services ecosystems provide (green box) can be grouped into three categories:
provisioning, regulatory, and cultural
History of Ecological Restoration
Industrial Revolution
-led to large-scale conversion of forests for fuel, agriculture,
and ship building
-so called “timber famines” in the 1600s caused dramatic
increases in fuels like charcoal
-European countries responded by establishing colonies
around the world
-by 1700s, reforestation became a part of colonial
administration
Example Mauritius had Dutch colonist that overexploited
timber and the when the French took over, they began
reforestation programs Figure 1.5
Figure 1.5 This print shows Mauritius as it appeared around 1800. French started reforestation
programs
Mining
Mining was initially done without regard to environmental
impacts
Ex. Sudbury, in Ontario, Canada had nickel and copper
mining operations that purified metals of sulfur by open
roasting using firewood
-denuded forest and released noxious gases Figure 1.6
-in 1928 Ontario legislature passed laws that metal
purification must take place in closed smelters
Ex. High numbers of worker deaths started reform in the
USA with initial laws related to worker safety and
prohibiting discharges of mine water into streams
Figure 1.6 A roast yard west of Sudbury, Ontario (circa 1900) denuded forest and release sulfer
gases into the air
Agriculture
Land conversion and poor farming and ranching practices
were more widespread than mining
Ex. Conversion of subtropical and Tropical forests to
coffee plantations in Brazil
-resulted in soil erosion and diminished water supplies as
cropland did not retain surface and groundwaters
-Forest Protection Act of 1934 in Brazil reduced
deforestation and motivated forest planting
Ex. Dust Bowl of 1930s
-caused the creation of Soil Conservation Service that
encouraged land use practices to reduce soil erosion
Natural Gardens
1870, Irishman named William Robinson published The
Wild Garden
-promoted freely growing plantings of hardy species in
underutilized spaces
-expanded the definition of gardening to include forests,
rocky knolls, stream margins, and bogs
-tried to match species to suitable environments but
sometimes used non-native species
Figure 1.7
Figure 1.7 Illustration from the first book on natural garden design, Robinson’s The Wild Garden
(1870)
Natural Gardening in the USA and Germany
Natural gardeners in the USA and Germany advocated the
use of only native species in natural gardening
-in USA, there was a broader debate that had begun
looking at large numbers of introduced species
-natural gardening with natives is a popular movement that
has persisted and grown
-1932 in Madison Wisconsin, university hired a
conservation professor, established a park and wildlife
refuge, and an arboretum. Here Aldo Leopold and two
botany professors, Norman Fassett and Theodore
Sperry created replicas of wetlands, forests, and prairies
that constituted the “original Wisconsin”. The professors
were as assisted by the Civilian Conservation Corps
(CCC), which was created to repair lands damaged in
the dust bowl Figure 1.8
Figure 1.8 A Civilian Conservation Corps crew planting prairie at the University of Wisconsin
Arboretum
Animal Translocations
Before 1900, New Zealanders recognized the extinction
and decline of many bird species primarily due to
introduced species such as goats, pigs, cats, rats, and
mice
Began translocating animal species to islands that did not
have exotic introductions and eradicating exotics from
islands
Established new populations of rare birds and also
observed a rebound in rare plant species
This led to restoration of whole communities such as Mana
Island in New Zealand Figure 1.9
Figure 1.9 Mana Island, New Zealand, was restored after livestock operations were abandoned.
Habitats were restored an burrowing seabirds were reintroduced
Restoration Ecology and ecological restoration
About 50 years after Leopold and his colleagues
reconstructed natural ecosystems at the University of
Wisconsin Arboretum, William Jordan, a scientist
inspired by how much had been learned about the
communities at the arboretum, coined the term
“restoration ecology”
Restoration Ecology-science of repairing ecosystems
Ecological restoration-process of assisting the
recovery of an ecosystem that has been degraded,
damaged, or destroyed
-restoration is necessary because of direct drivers but a
number of indirect drivers drive the land conversion,
nutrient additions, pollution and climate change,
overexploitation, and species introductions Figure 1.10
Figure 1.10 Direct drivers of human-caused ecological change are influenced by many factors
Cultural Drivers
Restorations reflect what people value
-cultural pressures to reverse environmental damage that
increases chance of human illness or death
-cultural pressures to reverse ecological damage to places
people cherish and nature that people value
Ex. U.S. Forest Service, the Confederated Tribes of Grand
Ronde, and the Confederated Tribes of the Selitz are
restoring Gordon Meadows in the Cascade Range of
Oregon to reverse damage to streamsides and bring
back harvesting of native plant foods. These cultural
values had been destroyed by fire suppression, livestock
grazing, and invasive species Figure 1.12
Figure 1.12 (A) Gordon Meadows, in the Cascade Mountains, Oregon. (B) The result of livestock
grazing and fire suppression. (C) Site plans include areas to process the camas harvest by native
people
Economic Drivers
Ecological restoration can stimulate economic growth by
providing employments and increasing the ability of
ecosystems to provide goods and services
Ex. South Africa’s Working for Water Programme
-program employs thousands that remove non-native trees,
which has greatly increased stream flows
Figure 1.13
Figure 1.13 Crew members clearing introduced Acacia trees as part of South Africa’s Working for
Water Programme
Demographic Drivers
Size of the human population strongly influences the
condition of the ecosystem
-population age and geographic distribution also influences
the ecosystem condition
-the rural to urban migration has allowed for restoration of
agricultural lands
-some countries have provided tax incentives for
restoration of agricultural lands, which provides a
economic driver that resulted from a demographic
change
Ex, Panama allows 100% of investments in reforestation to
be tax deductible
Technological Drivers
Development of new technologies drives the reversal of
some environmental problems
Ex. New ways to remediate pollutants and herbicides with
low-risks to human health used to control weeds on
restoration sites
Ex. Lampricide that selectively kills lampreys in the Great
Lakes that has allowed its native fish species like lake
trout to begin recovery Figure 1.14
Figure 1.14 Introduced sea lamprey parasitizing lake trout in Lake Superior
Sociopolitical Drivers
Societal decision making drives restoration in several ways
-participation of stakeholders
-resolution of disputes
-role of governments verses private sector
-levels of education of participants
Ex. U.S.-Canada Great Lakes Fisheries Commission was
formed to control lamprey and other environmental
problems
Ex. Baghmara Community Forest in Nepal
Figures 1.15 and 1.16
Figure 1.15 Residents of the Baghmara community weigh wood products harvested from the
community forest they restored and sustainably manage
Figure 1.16 The human population of the Chitwan Valley in Nepal rose dramatically when malaria
was eradicated and roads were built
Restoration programs generally focus on three different kinds of outcomes
Three outcomes of Restoration Programs
1. Species-based restoration
Ex. Two birds and one plant protected under the U.S.
Endangered Species Act was the impetus for the
restoration of Sweetwater Marsh in California
Figure 1.17
Figure 1.17 Providing habitat for the light-footed clapper rail, least tern, and a salt marsh plant
protected by ESA were the aims of the restoration of Sweetwater Marsh, California
Restoration programs generally focus on three different kinds of outcomes
2. Restoration of ecosystem function
-ecosystem functions involve a number of complex
processes that make this aspect of restoration a challenge
but extremely important for successful restoration
Table 1.1
3. Restoration of ecosystem services such as provisions
for human needs like food and fuel, water purification,
pollination, recreation, as well as aesthetics and spirituality
-these often receive much public support and the benefits
are easy to communicate and appreciate
Table 1.1
Nine outcomes of any restoration project according to Society for Ecological Restoration (2004)
1. Species used occur in reference ecosystems and
provide appropriate ecosystem function.
2. Native species should be used.
3. All ecosystem functions are in place or have the
potential to develop-material flows, biological structures,
and physical elements (Includes # 5 normal function
and # 6 fitting into the larger landscape)
4. Capable of sustaining reproducing populations.
5. Outside threats are minimized.
6. Resilient enough to sustain normal periodic stress.
7. Self-sustaining to the same degree as the reference
ecosystem.