Danielle Verrier NRS 509 December 16, 2014 Landscape Ecology, Archaeology, and GIS and RS

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1 Danielle Verrier NRS 509 December 16, 2014 Landscape Ecology, Archaeology, and GIS and RS An important facet of understanding the archaeological past is understanding how ancient peoples interacted with the environment in a reciprocal relationship. This reciprocal relationship is not only important for the past, but also may have implications for our present and future. Understanding people and cultures removed through time and space is almost impossible. Since we are only left with pieces of the puzzle, can never fully reconstruct it. Add into the fact that ancient peoples and landscapes were not static, but very dynamic things, and you get a complex mess that is difficult to interpret. GIS, as a spatial analysis tool, offers a way to make that complex mess more clear. However, it has not been fully utilized in the archaeological community until recently. Now that it has been introduced and its importance recognized, models and analyses have been booming. It offers an efficient way to organize and interpret spatial data that otherwise would have taken weeks or months to study. GIS and RS are used to find sites through human examination or predictive modeling, to correlate relationships between sites and environmental factors, and to analyze patterns such as site distribution and visibility. The location of sites is directly influenced by the landscape, both in the past and present. In the past sites were chosen based upon which environmental factors the people deemed most desirable. Today their locations can be affected by erosion and land shift. Sites which once sat upon high bluffs can be found strewn across the ground below, far removed from their original location. Predictive modeling is commonly used to locate sites. This model takes into account know sites and correlates them with environmental factors and cultural factors. From these factors a gradient model is created showing the possibility of sites across the landscapes. This interpolation method can sometimes serve and end in itself by revealing environmental patterns previously unknown. When looking at terrain ruggedness Bevan et Conolly decided to incorporate watersheds and discovered that each site was located on a watershed boundary. Not only is this an interesting and important piece of information to consider when theorizing ancient people s interactions with the landscape and their perceptions, but it also important for locating future sites. The predictive model they used earlier in their study can now be updated with the limitation that settlements (not all sites) be located on watershed boundaries. Thus the model can be manipulated depending upon which type of site you are interested in finding. The constant updating and testing of our predictive models is key. When a model does not present accurate results, we should continue to improve upon our input data. By keeping data up to date and accurate we will eventually be able to create standard predictive models for regions and subregions. While GIS is a great tool for predicting sites and discovering patterns, its most common use is bar far visibility and view shed analysis. This focus has been so strong in and outside of GIS in the archaeological community as to draw strong criticism and ire. While a focus on only visibility and view shed as a means to interpreting the past is narrow and short sighted, the use of these analyses in the big picture is beneficial. They also provide many uses. Visibility is an

2 environmental factor that can be considered when doing predictive modeling, and so determining its parameters and associations in different regions is important for its integration into such modeling. In González-Tennant s study view shed was an important factor in site location so that the people of the town did not have to hear the mining machinery. View shed analyses provide practical applications, but their application to theoretical archaeology is their common use. View shed analyses of important sites such as Minoan peak sanctuaries or monumental strictures such as Roman Barrows provide us a means for understanding how past landscapes appeared to people. We are able to recreate the landscape in which ancient peoples lived and to know how they physically viewed it. These studies do have their limitations however. When conducting visibility studies, our own perceptions are imposed upon the data, and we have a tendency to generalize rather than looking at the individual. It is clear how these factors affect datasets being input to predictive models and pattern analysis. We decide what we believe to be the environmental factors important in site location, and these may be true, or coincident to a different important factor. In visibility studies the issue is harder to see, but a unique study by Fitzjohn puts it into perspective. His study clearly demonstrates that people s location within a region and their daily activities greatly change how the landscape is perceived. Thus, our approach to generalize visibility and perception into view sheds is not accurate. GIS and RS in archaeology and landscape studies have come a long way, but there are still improvements to be made. The biggest hurdle is the issue of databases and accessibility. I have observed it to be the case from personal experience that each site keeps its own personal information, and is loathe to share their database information. More teamwork and database accessibility is necessary to create accurate and complete models. The Pequot Museum keeps a database of information for all of its site and frequently models and analyzes the data in ArcGIS. This is a method that would be ideal to follow, however unlikely due to feasibility. Regardless, more open access between researchers needs to occur if we are to move forward. Another issue is the impositions we make on data outside of GIS find their way into the GIS data and thus the result is models that include human bias and error. While this is an issue that can never be completely removed, more awareness on how we reflect our results (as show by Fitzjohn) will yield better results. More willingness to share, awareness of our biases, and awareness that our imposed limitations and relationships are not necessarily the truth will forward GIS in archaeology. The technology of GIS and RS is ready and waiting, and has much to offer. We must be ready to accept the change that technology brings, and accept the flaws in our approaches that it reveals to bring our understanding of the past to the next level. Annotated Bibliography Bevan, A. and J. Conolly GIS, Archaeological Survey, and Landscape Archaeology on the Island of Kythera, Greece. Journal of Field Archaeology. 29: Bevan et Conolly present case studies conducted on the Greek island of Kythera. Using a DEM they extracted slope value from agricultural fields to look at the interface between fields and terracing as agricultural methods. In the second case study Bevan et Conolly examined surface visibility and showed through their findings that there is not relationship between surface

3 visibility and site and artifact discovery. Their third case study examined the visualization of on an off-site distribution patterns, methods to identify clustering, and interpolation to understand distributions. By creating a variability surface containing known site distributions, the patterns that determine on and off site deposits can be more clearly defined. Bevan et Conolly s final case study correlated site location with cultural and environmental variables. Unfortunately the authors did not go into great detail in their modeling methodologies, but regardless they give a good presentation of the practical applications of GIS in ancient landscapes. Using GIS they defined some of the landscape patterns for ancient Kythera, and in so doing have developed models for interpreting similar ancient landscapes. By building upon models such as these, as they have suggested is necessary, we can better understand the dynamic relationship between ancient peoples and the landscape. Eckardt, H., P. Brewer, S. Hay, and S. Poppy Roman Barrows and their Landscape Context: a GIS Case Study at Bartlow, Cambridgeshire. Britannia. 40: Eckardt et al investigate the view sheds and visibility of the Roman Barrows at Bartlow, Cambridgeshire in England by using GIS modeling. Differing opinions suggested that barrows were monumental pieces meant to be seen from important roads or that they were meant to be seen locally and associated with one town area and villa. The data used by Eckardt et al was the Ordnance Survey Land-Form profile DTM and LIDAR DTM. By assigning height values using a topographical survey of the barrows and combining it with a view shed analysis they created a gradient map of how visible the barrows were from certain locations. Using evidence for local villas and Thiessan polygons, a hypothetical reconstruction of the Roman Bartlow estates was created. Combining all of these models it becomes evident the barrows were local to one estate. The use of GIS in this manner allows us to investigate and answer questions with more certainty, but we must be careful to remember that while the software develops accurate results, the results are only as accurate as our data. Eckardt et al make assumptions in their data, as will any archaeologist in these circumstances by necessity, and so we need to be aware that the results will reflect these assumption. Eckardt et al recognize that issues with these types of models imposed upon ancient landscapes, but there is room for more discussion on the issue. Fitzjohn, M Viewing Places: GIS Applications for Examining the Perception of Space in the Mountains of Sicily. World Archaeology. 39: Fitzjohn took a unique approach to the application of GIS in understanding the visual aspect of space in archaeology. A large focus in Western European archaeology has been and still is visibility studies. Visibility studies are based on the assumption that there is significance in the inter-visibility of monuments/important locations and the views of or from them. Fitzjohn conducted a study to show how perceptions change through many factors including time and experience and we must be careful not to impose our own perceptions upon visibility and space. He conducted photo elicitation studies of the Troina landscape on a broad of range of local inhabitants with differing ages, genders, and occupations. Within the Troina GIS two layers were created relating to the photo elicitation study: a point layer representing where each person lived and containing information about their life, and a polygon layer representing the 24 photographs used in the study. The integration of this data revealed a relationship between the interviewee s response, and their occupation and home location. Fitzjohn s study reveals numerous issues with

4 how we view the past and people in it. Unusual uses of GIS such as this are needed to show bias of the investigators and develop a relevant model for how current people live in the landscape. González-Tennant, E Using Geodatabases to Generate "Living Documents" for Archaeology: A Case Study from the Otago Goldfields, New Zealand. Historical Archaeology. 43: González-Tennant discusses the developing roles of GIS in archaeology, and their classes as defined by Mark Aldenderfer (1992). Aldenderfer divides GIS in archaeology into three classes: (1)the traditional use of GIS to create maps, (2) to complete complex analysis, such as predictive modeling looking at known sites, resources, and landscape, and (3) looking at new and unique methods of analysis, such as cost surface analysis and view shed analysis. One of the greatest difficulties currently faced in the use of GIS in archaeology is the lack of information regarding schemes used to organize the data itself. González-Tennant s intention is to fill this gap by discussing at length and in detail the methodology used for his study at four Otago goldfields. He provides information on the GPS information gathered, instruments used (Trimble GeoExplorer CE XT), test measurement protocol, and accuracy assessment and DOP (dilution of precision). The data he gathered was then compiled in ArcGIS into a geodatabase, the steps of which González-Tennant discusses. The final analysis which was a simple view shed to look at the use of natural barriers in settlement placement, was almost an afterthought. The intention of this paper to define schemes and methodologies applicable to all archeologists, rather than focusing on the study results was a success. This paper is itself a tool for archaeologists, and both can and needs to be built upon as we learn more about how to best utilize GIS technologies. McCoy, M.D. and T.N. Ladefoged New Developments in the Use of Spatial Technology in Archaeology. Journal of Archaeological Research. 17: McCoy et Ladefoged give a thorough review of the current uses and applications of GIS in archaeology. GIS is used for data visualization and representative visualization so that patterns may be identified, sometimes just by the human eye discerning manmade patterns from natural processes in an RS photograph. GIS is also used for data management; it has become the platform by which archaeologists now store their information at the site, feature, and artifact levels. Prospecting, modeling, and spatial analysis are the newer uses of GIS in archaeology. Prospecting utilizes RS methods, using geophysical survey, aircraft based laser mapping and imaging, and satellite imaging to locate potential sites. In the Maya region researchers used the Landsat Thematic Mapper, IKONOS, Quickbird, STAR-3i, and AIRSAR to find sites by hecking vegetation signatures. Site predictive modeling correlates known sites with environmental and cultural factors to predict in which areas sites are most likely to be located. Spatial analysis is most commonly used for view shed and visibility analysis, but more recent uses have included a focus on behavioral modeling centered on the movement of people through the landscape. Archaeologists rarely use agent based modeling, but recently, with new developments in GIS, they have begun to utilize it. The technologies used in archaeological GIS include, but are not limited to, DPS units and base station data, ground penetrating radar, proton magnetometry, electronic resistivity/conductivity, sonar, IKONOS, Quickbird, air photographs, CORONA, laser

5 total station, Lidar, ESRI ArcGIS, MapInfo, GRASS, Quantum GIS, ERDAS IMAGINE, AutoCAD, Microstation, and Mobile GIS. Their report is thorough and serves as a handbook and guide for anyone wishing to implement GIS into their archaeological studies. McEwan, D.G Qualitative Landscape Theories and Archaeological Predictive Modeling A Journey Through No Man s Land? Journal of Archaeological Method and Theory. 19: McEwan reviews the need for new ways to approach GIS in archaeology after showing the accuracy or lack of accuracy in certain approaches. Predictive modeling has grown in use in North America and the Netherlands, but has yet to be fully utilized elsewhere. His review focuses on two predictive models designed to predict the locations of Neolithic settlements in Scotland. The processes of recalibrating models when new input sites are discovered and testing the validity of the predictions upon completion of fieldwork are vital, and yet they have been neglected in recent years. McEwan tests the accuracy of the two Scotland models, of which the first is statistically the most accurate, but when mapped it identifies an entire area as highly likely for sites without clear distinction between low, medium, and high possibility. Model 2 comes in second in its success of predicting sites, but when mapped, it is the best result showing clear differences in site potential. Both models are useful for different purposes, but fail to truly reflect the landscape completely. Revision is obviously needed in these models. While McEwan makes a good case for the need for revision and testing, he does not mention what the actual models used are or how they were created which greatly detracts from his review. Rennell, R Landscape, Experience and GIS: Exploring the Potential for Methodological Dialogue. Journal of Archaeological Method and Theory. 19: Rennell discusses the uses of GIS in experiential archaeology, the idea that the how people experienced sites and landscapes can lead to an understanding of the past. She first discusses the criticisms and defenses of the use of GIS in subject centered and experiential study. Some people believe GIS encourages an objectified view of the archaeological world, while others defend it as another tool in the interpretative process and not the final product. Rennell focuses more on establishing methodologies outside of GIS here, and how they then are used within a GIS context. Since the issues with GIS in archaeology mostly arise from external factors, I believe this to be a good approach. She explores the characterization of place, movement, and the communication of experience with the use of subject centered field practices and of GIS based view shed maps. Such studies incorporating traditional methods and GIS methods are integral steps in understanding how GIS is best utilized, and how we, as researchers, affect GIS models and analyses through our data interpretation. As Rennell points out, the two approaches are only partial, and they exist at differing ends of the spectrum. By combining them we are able to reach a more thorough understanding of the past than we would be relying on just traditional methods or just GIS methods.

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