Typically, when considering ecological restoration, what comes to mind is the renewal and restoration of natural ecosystems and habitats that have been damaged, degraded, or destroyed by human intervention to their original, un-intervened form. However, recently published in the Journal of Applied Ecology, is a study known as ‘Prioritizing Sites for Ecological Restoration Based on Ecosystem Services’ (Comín, F. A. , Miranda, B. , Sorando, R. , Felipe-Lucia, M. R. , Jiménez, J. J. , & Navarro, E. 2018. Prioritizing sites for ecological restoration based on ecosystem services. Journal of Applied Ecology, 55(3), 1155-1163. doi:10. 1111/1365-2664. 13061) which looks to use ecosystem services as a means of electing sites in need of restoration. Within the article the authors attempt to demonstrate a new method – called the Relative Aggregated Value of Ecosystem Services Index or the RAVES index – which can be used to evaluate and then hieratically prioritize the state of natural degraded lands for restoration. By employing the RAVES index on a test site, located in the watershed area of the River Piedra in Guadalajara-Zaragoza, Spain, the study attempts to illustrate the potential benefits of using the RAVES index to determine the restorative actions required to improve the current provisional state of ecosystem services within the River Piedra area.
The RAVES Index entails the evaluation of the current and possible ecosystem services present within the site based on a fixed set of criteria. Through a series of laboratory and field studies it is determined which ecosystem services are present. Then, each service is assigned a relative ‘weight’ by a committee of non-biased professionals which determines its importance based on the ecological status of the site. For example, within the River Piedra site, soil retention and the establishment of habitat for biological species were two of the most prioritized services. 2 When considering the introduction of the paper, it is, for the most part easily understandable, and direct with its points. There are typically one or two citations within each sentence demonstrating that in depth research has been done to support the arguments that have been made. However, the in-text citations somewhat overwhelm and take away from the information that is being provided. Despite that, it is possible to understand the details about why the method they have developed is a necessity when working on large scale sites and how it is beneficial to use the RAVES index to determine which areas display the greatest need of restoration. However, when the study is first mentioning the RAVES index method, it is introduced in the paper under the pretence that the practice of restoring degraded natural land to its original undisturbed state is no longer a viable method of restoration. It is stated within the introduction of the paper that there is a serious lack of pristine undisturbed reference sites off which to base restoration in the first place, and that the way in which restoration has been performed historically does not incorporate societal values within its design.
Although in some cases this may be true, such as in the work that was cited alongside the statement, it is not the case. Conventionally, restoration ecology attempts to re-establish ecological attributes, functions, integrity, sustainability and processes that have been degraded within a site and return them to their undisturbed (by human intervention) state. When a lack of data pertaining to what natively occurred within a site prior to its damaged condition – such as plants or animals – it is possible to discern them through research into the site location, such as investigating historical documents or an analysis of the surrounding areas’ topography or soil profiles. With regards to social values not being met: ecological restoration may not be centered around human benefit – as ecosystem services are explained to be – and thus it can easily be said that it places less significance on 3 social values, however, ecologically restored sites have the ability to create a large impact within communities. For example, a block of a suburb is converted to a recreational green space, it becomes an active choice, rather than a passive act, that requires individuals to interact with and experience the environment around them. It is able to restore the wonder, worth and the elusive sense of place to an area – through the participation of a community.
Although Ecosystem Service may place a more distinguishable worth in societal values, by curating to an anthropocentric ideology, its emphasis is on the instrumental values that co-benefit humans while excluding the intrinsic value of different natural entities. In some cases, devaluing, or altogether disregarding, the importance of emotional, cultural and spiritual values within societal values that are an integral part of connecting and appreciating the wonder of nature. The methodology is described throughout six clearly labeled headers, each detailing a different aspect of the process. First, the location of the study area – River Piedra located in Guadalajara-Zaragoza, Spain – is described in great detail giving the exact location, the climate type, giving details on the native biological life. It is very succinct and easy to follow, it is not overwhelmed with extra information, allowing for a very clear idea of what the exact site must be like. Next, the authors go on to describe the process through which they went to rank and prioritize areas for ecological restoration based on the RAVES Index. First, the study identified the 15 main Land Use Land Cover or LULC types that were present within site boundaries though the consultation of national land maps at a scale of 1:50,000 based on satellite imaging and orthophotography. The maps and satellite images were both sited within the text. A field survey was then conducted to place 120 plots measuring 30m x 30m randomly across the site to test the RAVES Index. Through this test the RAVES Index identified finer categories within current LULC types, allowing for a final count of 19 obtained 4 LULC types and an improved LULC map. After the test was completed, 11 ecosystem services that could be found within the River Piedra watershed were selected (ten regulating services and one aggregated indicator of cultural services) to be used within the study. Please note that it did not include Provisionary Services for within this study Provisionary Services were seen as a trade off with other ecosystem services and were not considered adequate for guiding ecological restoration. While it is understandable why the study did not include Provisionary Services, it is a missed opportunity that excludes an entire other entity of data that could have been useful to the study. A figure is inserted into the paper on pg. 1157 (or pg. 3 of the PDF) which is meant to visually illustrate the whole process. It is slightly confusing and overwhelming to look at, as the whole process has yet to be explained, and there is a multitude of colour coordinated labels that correspond with multiple overplayed maps of the site. It could be illustrated in a more organized manner that better emphasizes the process, such as an enlarged or two part visual.
The next stage of the study unified all the collected data – to limit the variability between separate data sources, each ecosystem service was amalgamated to raster and vector maps of 20m x 20m. The mapped values and the spatial distribution of each plot was done using GIS mapping. To determine the significance of each individual Ecosystem Service and its relative function a material analysis was conducted using an expert panel who then gave each individual Ecosystem Service a corresponding ‘weight’ based on their unbiased opinion. Truly knowing if an individual is unbiased – or if it is possible for someone to be unbiased, even unconsciously so, is impossible. To trust that each expert was truly unbiased, even if a sensitivity analysis was 5 performed, when giving each Ecosystem Service its ‘weight’ seems like a large uncontrolled variable within the study. If it were possible to assign the ‘weight’ of an Ecosystem Service though the use of a computerized algorithm would allow for more reliable data. Each 30m x 30m plot was then analyzed by the RAVES index and given a priority rank of 1–10 for determining necessary restoration. Where values 1–4 indicate high priority areas, 5–6 indicate medium concern and 8–10 require preserving current conditions A table detailing the multiscale spatial analysis of ecosystem services at the River Piedra watershed is then provided. There are no actual statistics within the table, they are indicated by the number of asterixis provided in each row (provided below). The necessary data to understand the table is provided in the subscript below the table. Which was unnecessary due to the fact that the data would have easily fit within the table, therefore making it easier to interpret and less confusing when first looking at it. There should be no need to go looking for data that should have been clearly presented. In the final stages, the researchers then determined four separate scenarios based upon the availability of the land for restoration and the availability of funding for performing the restoration. Scenario 0: Baseline Scenario – current situation; Scenario 1: Restoration in private lands – private lands available with limited economic funds); Scenario 2: restoration in public lands – public land and economic funds available; Scenario 3: restoration in both public and private land (land and economic funds available).
The results of the study determined that there is a large variation in the amounts that each Ecosystem Service supplied to the River Piedra. It was determined that forested LULC types possessed the largest Ecosystem Values, while urban LULC had the lowest values per amount of possible ecosystem services. The final recommendation based on the RAVES Index and the unbiased experts was that the key ecosystem services within the River Piedra were soil retention, refugium and habitat, and the regulation of water, waste, nutrients, gas and climate. And it was suggested that restorative action be taken to improve provision of the key ecosystem services within the study area (i. e. Reducing sol erosion, afforestation and thinning to decrease intraspecific competition and to increase tree height). It was concluded that the highest and therefore least degraded ecosystem services within the site were found to be most prominent in the central area of the watershed – most of which were dominated by riparian forests. While the Lowest RAVES values were found in southern end of watershed – which are mainly composed of rainfed cereal crops, and extremely low RAVES values found in sites with hillside agriculture, highly eroded scrublands, highly eroded slope, and degraded forest areas. these findings seem to follow the general trend that the more human intervention present within a site the more degraded it will be, thus resulting in it needing more restorative action than other areas that display a limited degree of human interaction.
The final condensed results found that 78% of the river Piedra site displayed RAVES classes ranging from 5-7, 15% range from 8-10 and only 7% displayed a low RAVES value of 1-4. In the discussion, the researchers explained that the sites with the lowest RAVES values corresponded to a higher priority for restorative action. They proposed that the RAVES index could be used to prioritize sites for ecological restoration but also be used for other management approaches, such as enhancing rural livelihoods maximizing social-ecological values, increasing 7 environmental aware-ness or biodiversity conservation. In each case, it was stated that the relevant Ecosystem Service needed to be identified and weighted accordingly. As mentioned, the study did not include data on Provisioning Services, however, the RAVES index is still able to identify agricultural areas with high and low RAVES. Finally, it was established that the largest increase in RAVES would be attained in a scenario where both social and ecological conditions were met (availability of the land and availability of funds). No new questions were raised in the discussion. It could have been mentioned that there is a possibility for this method to be used globally in the future, due to the fact that the increased rate of destruction caused by human action will accelerate exponentially as a result of the growing population. Which is a scenario that many Landscape Architects struggle with solving.
This provides a possible solution to the severe problem, as it could provide a sustainable way to supply people with the resources they need while also maintaining the integrity of the environment. This study was, for the most part very insightful and well prepared. There were a few issues surrounding the overwhelming inclusion of long-winded sources within the text, which distracted from the intended information, however it was still navigable. There was a statement that mentioned that conventional restoration ecology is a dead practice, which seems debatable on many fronts but is subjective. Some of the visuals were unclear in their presentation, and the use of ‘unbiased’ experts within the study is questionable, however it seems the data was not badly skewed in favour of one ecosystem services versus another. Not including the Provisional Services within the collected data could have affected the results of the study, however mentioning that the RAVES index also works when used on Provisional Services is helpful information for anyone wishing to do a study of agricultural areas or other such areas. The 8 information provided offers useful insights, for Landscape Architects when considering a design, on how to best combat degradation within ecological site while also providing the needed resources and ecosystem services required by the population.