Tuesday, December 14, 2004

Although it is a more recent development in the scientific community, ecological restoration is a discipline that is not devoid of myths. Stanturf et al. (2001) addressed nine myths, misunderstandings, or partial truths that have surfaced while evaluating the success of bottomland hardwood forest restoration.

Afforestation is not the same as restoration. In my opinion the authors dispel this myth too readily. I don’t believe that this myth is entirely false, though it appears that the authors, contrary to their initial statements, do not either. I agree with their claim that afforestation is a necessary step in any forest restoration process. Furthermore, they assert that functional attributes are highly correlated to vegetation, especially forest cover, and also that a component of the hydroperiodicity of an area is the amount of canopy evapotranspiration. Afforestation is indeed related to both of these aspects, and the reintroduction of trees is an obligatory phase for restoring a bottomland forest. However, I cannot dismiss the myth that afforestation is not the same as restoration, simply because it is not. Ecosystems are exceedingly complex (more knowledge gained about them reveals yet much more that is still unknown – “the more you learn, the less you know”). The primary physical component responsible for maintaining bottomland hardwood forests is hydrologic regime, which has been drastically altered in most regions by human activities; flooding of riparian areas has increased in intensity and frequency. An afforested bottomland area will likely become a monoculture of trees (like silver maple) that are tolerant of intense flood events. This scenario could be likened to a plantation, rather than a natural functioning ecosystem. Yet according to the refutation of the myth, this reforested area would be a restoration success. Even Stanturf et al. (2001) go on to state, “There is more to restoration of a bottomland ecosystem than afforestation.” It seems then, the authors may have meant to say that afforestation is an important step in restoration. Certainly, restoration of bottomland forests is a much more intricate process than reforestation. Later, the authors claim that afforestation is a vital component of a restoration project, keeping the myth intact. Bluntly, afforestation is a tool of restoration, and not an analogue.

Restoration is easy – Anyone can do it. If restoration is viewed as afforestation, which it is not, then many believe that it is an easy task and that anyone can do it. If we follow in the misguided footsteps of the authors and view afforestation as restoration we will see that it is still not easy. Some of the problems that occur are poor seed sources, ill-prescribed species, improper storage of seeds and seedlings, and poor planting techniques. People also try to transfer the successes of one site and apply them to others. This approach is like prescribing everyone the same drug for a symptom of a stomachache; this is not a good idea if you are not aware of individual patient’s histories. They provide data for their attack on the myth, stating that 90% of the area enrolled in an afforestation WRP program in Mississippi failed. Furthermore, following my opinion that afforestation is not restoration, it can be seen that restoration is not easy as well, because if afforestation fails and is only one step then, statistically speaking, this multi-step task would fair even worse.

Desired future condition can be specified. Many people enjoy using reference sites as a gauge of restoration success. The authors view this method as problematic due to various factors. If one uses reference forests from the past they are neglecting to look at changes of the environment such as alteration of the flood regime and climate. The authors think that a better way to evaluate success is that of function and not naturalness. The fiction behind this myth is that future condition cannot be specified, at least at the individual level, and thus shouldn’t be used a guide to evaluate restoration success. To improve on this myth I would integrate the idea that nature isn’t linear. Using some of the ideas from Young et al. (2001), given all the factors present on a “successional trajectory,” we should expect different outcomes, at least on an individual level, to have a certain degree of uncertainty within them.

The same strategy is appropriate to all ownerships. I agree with the authors that this is absolutely a myth about restoration. The authors distinguish between private and public lands and the differences between restoring them. They discuss the differences in management goals and in restoration applications of such lands. This myth is a blanket statement and these are huge generalizations that are not custom-tailored to each and every system.

Plantations have no wildlife value. According to the authors of this paper, others have shown that there is value in intensively managed forest stands. However, many wildlife managers would like to opt for the lower-cost extensively managed approach. This approach typically takes at least 20 years before forested stand conditions exist. During this time many opportunities for species other than game species would be lost and the resulting stand would be insufficient to manage well. An intensive stand approach would provide more diversity at much more rapid rate as well provide opportunities for manipulating stand composition. Here, the authors explain how some plantations do indeed have wildlife value. I agree with them insofar as saying that this is a myth. Plantations do provide value for wildlife albeit contrived.

Understocked stands are sufficient. Canopy cover is the criterion for success of a forest stand. An intensively stocked stand can be considered a success in as a few as 2 years whereas an extensively stocked may take 20-40 years to reach the same level of canopy cover. For human desires related to management the 2 year track is much more desirable. Keeping this in mind, the statement “understocked stands are sufficient” is true. To improve this myth I would be sure to include something about humans and human conception/value of time, otherwise this myth would be true and not a falsehood. In my opinion to debase this myth one needs to use a timeline more suited to humans than say nature.

Preservation is the only valid goal. I agree with the authors that this is a myth. There should be other goals in a restoration plan besides preservation. The authors see ecological restoration as an element in the continuum model of sustainable forest management. They see restoration of a forest as moving the forest along a continuum from degraded to natural, which as a functional component goes from restoration to self-renewal. Since management is incorporated into many restoration plans, we would expect that harvesting might occur. The authors agree that this is feasible and with this they continue to negate that preservation is the only valid goal. To further disintegrate this myth, I would discuss, to a degree, what it means to restore a site. According to Katz (2000), restoration is not natural but rather a human artifact. Restoration functions, then, only to fulfill a human want, and if that desire is not preservation, then there are other valid goals. Also, restoration is not a complete transmogrification of what a degraded area now is into what it once was; rather, it renews certain facets of a said natural area. If someone only restores the properties related to sport fishery of a certain lake, then their goal is not preservation, but they are still restoring an area.

Ecological and economical goals are incompatible. I agree with the authors that this statement is indeed a myth. At a rudimentary level it requires a dichotomy between ecology and economy and nothing is that simple. There reasoning for absolving this myth is that, yes, these two are not mutually exclusive. With regards to forest restoration and wildlife management they state how there are cases where selective harvesting improves vegetative structure for wildlife. This harvested timber could be sold and ease some of the economic burden related to the wildlife management. To further expound upon this myth I would talk about ecosystem services. A restored area that is moving on the trajectory from restoration to self-renewal could provide other services that do not usually have a value attached to them. Processes such as erosion control, flood control, et cetera could be expected to occur at some restored ecosystems and these services could provide economic relief to said area.

Restoration can proceed without management. The authors are self-reportedly pro-management people and they believe that an extensive strategy does not meet federal program objectives for restoration and that the more benefits realized from intensive benefits outweigh the increased costs. I would disagree that restoration can proceed without management is a myth. Excluding major disruption i.e. mining, toxic waste, et cetera nature has a way of restoring itself without human intervention. The problem with this idea for humans is the timeline. Obviously, a “natural restoration” would take longer than most humans are willing or able to wait. However, this doesn’t stop nature from moving on its path towards the natural condition found on the restoration trajectory. According to Katz (2000), restoration is a human intervention and with that comes human time frames. Time is a human-contrived notion; nature’s perception is different from ours.

I agree with the authors for the most part on many of their arguments. Where I failed to agree with them was typically on issues related to timelines and conceptions about restoration as restoring nature rather than creating a system to produce a human want.

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