This really depends in the point of view. Some colleagues indeed argue that ecological restoration is supposed to revert a degraded ecosystem to a "pristine," i.e. pre anthropogenic impact state. However, this is rather extreme, because there is hardly any system that has not either for a long time, or in the past, sustained anthropogenic impact. Even large parts of the Amazon, as well as many "virgin" (and very diverse) cloudforest areas in South America show clear signs of previous human use and management. The most useful definition of ecological restoration would be to restore a degraded system to fulfill a defined ecosystem function.

This really depends in the point of view. Some colleagues indeed argue that ecological restoration is supposed to revert a degraded ecosystem to a "pristine," i.e. pre anthropogenic impact state. However, this is rather extreme, because there is hardly any system that has not either for a long time, or in the past, sustained anthropogenic impact. Even large parts of the Amazon, as well as many "virgin" (and very diverse) cloudforest areas in South America show clear signs of previous human use and management. The most useful definition of ecological restoration would be to restore a degraded system to fulfill a defined ecosystem function.

I agree that restoration ecology is context-dependent. However, it implies some kind of action or management that is identified or intended. Re-storing means basically to re-establish ecosystems or species populations. This does not necessarily have to be related to pristine ecosystems or even native species. Taking a functional point of view it can also include assisted migration and the establishment of novel ecosystems that can be expected to be adapted to future climatic conditions. However, this understanding is not common sense in the restoration ecology scientific community that is either focused on nature conservation or on the compensation of negative impacts due to human disturbances (e.g. mining).

There is these concepts of restoration trajectory(resembling succession)reclamation,rehabilitation,Restoration sensu stricto...i m just confused.

Eco restoration is  helping a degraded ecosystem  to get back to the original condition. The best way is to help to get back the original abiotic environment  and keep the system  with least interference, so that  nature will try to heal the wound.

I miss historical context. In most cases I have studied in all inhabited continents a sequence of ecosystems have historically preceded the current one. It is a matter of choice (with biodiversity as a guide) whether to aim at establishing pre-farming vegetation mosaics, farm-natural vegetation mosaics or new nature including wilderness on abandoned farms. In the latter case excepting hard-to-reverse developments in soil, flooding regime and so on.

CALIFORNIA PERSPECTIVE--From a California perspective, we focus on the 100% elimination of exotic plants, and ecological restoration to us, means creating a weed-free ecosystem that is made up of local ecotypes of native plants, and to be able to accomplish that massive feat within a few years.    The elimination of all exotic plants, and putting back the local native plant material so that it is 100% cover, is the hallmark of the concept of "Ecological Restoration."

WHAT WAS "RESTORATION" BEFORE ECOLOGICAL RESTORATION? Prior to the concept of ecological restoration getting established by the government agencies in the USA, say 1990-2000, whenever you were "restoring" a piece of land, say after mining or construction, you could throw some invasive exotic seeds out of the back of your pickup truck as you drove away, and called the land "restored" in that it was now going to be covered by some type of vegetation, but nothing close to what grew there in pre-European times.

GAS PIPELINE AS AN EXAMPLE--There is a 1.7 mile gas pipeline that just ran through some California State property this last year, a 95% pure native serpentine grassland containing five Special Status plants, and the gas company did not tell the State that they were disturbing this sensitive habitat.  Nobody has ever successfully restored serpentine grasslands back to 95% native cover before, and nobody had ever restored any of the five Special Status plant successfully before either.

In California, because our State is covered about 100% by over 1,000 exotic weeds, that makes ecological restoration very expensive and very difficult, if you are trying to put a broken ecosystem back together from scratch.  

SMALL SCALE TEST PLOTS--What should be done, is small-scale test plots planted until you have 100% success for each Special Status plant you are trying to restore, and also have successful test plots for the overall ecosystem you are trying to replant.  

But because of the costs to achieve the successful test plots, about $1 million per species or $1 million for a whole ecosystem, (when a house costs $1 million minimum now in California) a fall-back term has creeped into the profession, called "ADAPTIVE MANAGEMENT" which means we really do not know what to do, and we are going to use the whole project as one big test plot, and hope for the best.

ECOLOGICAL RESTORATION DEFINED--So the bottom line definition for Ecological Restoration in the real world, is "Zero exotic plants, and 100% local native plants, and put together so that it can go on its own after a fashion, and not collapse back into a big weed patch."    

HOW FAR BACK DO YOU GO?--All of the discussions about how far back you go in time, in the Americas, Africa and Australia it would be to the pre-European contact, and only use local native plants. In Europe, if you are restoring a natural area, I would go back to the pre-agriculture and pre-domesticated animal eras.  

Any other discussions, like how did the Native Americans modify the vegetation of the Americas, etc. is purely abstract, and only rolling up your sleeves and rebuilding an ecosystem using the local native plant materials, will be the only thing that matters at the end of the day.

These are my perspective being one of the elders doing this work for over 40 years now.

$10 MILLION BOND. I forgot to mention, that the bond that the gas pipeline company is required to post for the 1.7 mile ecological restoration project, is $10 million.  That means that before we destroy any native ecosystems, we need to have invented the proven ecological restoration methods, that can put those ecosystems back together quickly, efficiently and back to their original quality.

ECOSYSTEM VALUES?--It also means, that when we realize how much it costs to put an ecosystem back together from scratch, now the intact examples of native ecosystems  have an economic value themselves, on top of the raw law real estate value. 

TEST PLOTS UNTIL YOU GET IT RIGHT. Worldwide, every ecological restoration professional, on top of doing their regular projects, should be paid by future projects, many years prior to the construction project occurring, to do small scale test plots, to invent the ecological restoration methods that will work once the big project is completed.  

You can see where I always do those pre-construction test plots years ahead of the project, at http://www.ecoseeds.com/greatbasin.html to end up with a successful large-scale project at the end.  And the professionals need to be paid for that pre-work, and clients should not expect us to have done that work for free.

LICENSE THE SUCCESSFUL METHOD--If you are able to invent ecological restoration methods that are more successful than your competitors, you should license those technologies to your clients, make the successful technologies have a value in themselves.  Every computer program in the world, even the free shareware, are licensed for use, that is what drives innovation in the computer industry.  Ecological restoration has forgotten that successful technologies should be licensed, not shared for free, so the clients recognize that they have a value in themselves.

Ecological restoration refers to the application of ecological principles to manage or reconstruct a degraded ecosystem or to increase the population size of a threatened species.