Restoration is an iterative process that includes:
1. Examining preexisting, historic, and current reference conditions prior to designing the restoration plan.
2. Developing a restoration plan.
3. Obtaining the necessary permits, where relevant, to perform the work for restoration.
4. Implementing the design, which can include modifications to soil, hydrology, and plant and animal communities as appropriate.
5. Monitoring of the restored site
Restoration ecology is the science of restoration-the research and scientific study of restored populations and ecosystems (Primack et al.2013).
Ecological restoration is the practice of restoring the species and ecosystems that occupied a site at some point in the past. It is “the process of intentionally altering a site to establish a defined, indigenous, historical ecosystem. The goal of this process is to emulate the structure, function, diversity, and dynamics of the specified ecosystem”
Objectives of restoration
The objectives of reclamation work are frequently prioritizing the stabilization of the terrain, removal of pollutants, assurance of public safety, aesthetic improvement, revegetation, or some combination of these activities.
Alternatively, re-creation returns a habitat to a particular historic condition, but there is no implication that the historic condition is an accurate alternative to undisturbed regional reference ecosystems; recreation could return a site to any chosen historic condition.
Importance of ecosystem restoration
Ecological restoration reestablishes functioning ecosystems, with some or all of the original species or sometimes a different group of species.
- It has been estimated that the current extinction rate is 1,000 to 10,000 times more than the normal rate.
- For many people, biodiversity has an intrinsic value that humans have a responsibility towards other living things and an obligation to future generations.
- Natural ecosystems provide human society with food, fuel, and timber.
- Fundamentally, ecosystem service involves the purification of air and water, detoxification and decomposition of wastes, regulation of climate, regeneration of soil fertility, and pollination of crops. Such processes have been estimated to be worth trillions of dollars annually.
- Habitat loss is the leading cause of both species extinctions and ecosystem service decline. The two ways to reverse this trend of habitat loss are conservation of currently viable habitats and restoration of degraded habitats.
- Some ecosystems destroyed by intensive human activities such as mining, ranching, and logging may have lost much of their natural ability to rebound and will not recover on their own without human intervention (e.g. Beeshazari lake restoration in Nepal).
- Some ecosystems have been so severely degraded by human activity that their ability to recover on their own is severely limited.
- Recovery is also often unlikely when the damaging agent is still present in the ecosystem, for instance, restoration of degraded savanna woodlands in the western United States is not possible as long as the land continues to be overgrazed by introduced cattle, reduction of grazing pressure is obviously the key starting point in restoration efforts there.
- Restoring natural capital such as drinkable water or wildlife populations.
- Mitigating climate change (e.g. through carbon sequestration).
- Helping threatened or endangered species.
- Aesthetic reasons
Approaches or practices of restoration
Ecosystems can be damaged by natural phenomena such as hurricanes or fires triggered by lightning, but they typically recover their original community structures and even similar species compositions through the process of ecological succession, however, the degradation rate is accelerating so dramatically due to human intervention. Therefore, the following are different approaches with which the ecosystem can be restored.
No action:
Restoration is deemed too expensive, previous attempts have failed, or experience has shown that the ecosystem will recover on its own. Such passive restoration occurs when abandoned agricultural fields return to the forest.
Rehabilitation:
A degraded ecosystem is replaced with a different but productive ecosystem type (for example, a degraded forest might be replaced with a tree plantation). Just a few species may be replaced, or a larger-scale replacement of many species may be attempted.
Partial restoration:
At least some of the ecosystem functions and some of the original dominant species are restored.
An example is replanting a degraded grassland with a few species that can survive and are critical to ecosystem function while delaying action on the rare species that are part of a complete restoration program.
Complete restoration:
The area is restored to its original species composition, ecosystem structure, and ecosystem processes with an active program of elimination (or reduction) of damaging agents, site modification, and reintroduction of original species.
