Atasta Flores E.

Archaeological excavations atYaxnohcah have revealed a long sequence of sedentary occupation, from1000 b.c. to a.d. 1400,with dynamic
periods of growth occurring during the Middle (1000–400 b.c.) and Late Preclassic (400 b.c.–a.d. 200). Twoof these complexes,Grazia and
Helena, serve as case studies that reveal the transformative processes of this period, illustrating site evolution on a larger scale. The Grazia
platform probably began as a residential area in the Middle Preclassic and acquired an increasingly public character throughout subsequent
modifications, culminating in the construction of a triadic temple platform and a ballcourt. A long sequence of fire rituals and altars show the
importance of the Grazia complex as a center for collective ritual. Helena also features Middle Preclassic domestic constructions, but was
transformed into a ballcourt platformduring the transition to the Late Preclassic.Both cases showthatYaxnohcahwas founded as awidespread,
loosely integrated settlement in the Middle Preclassic and evolved into a formally and centralized network of communitieswith their respective
nodal centers in theLate Preclassic period. Placemaking and the rise ofmonumentality played an important role in this transformation and reflect
the particular forms of community integration.

This study proposes a sampling method for ground-truthing LiDAR-derived data that will allow researchers to verify or predict the accuracy of results over a large area. Our case study is focused on a 24 km2area centered on the site of Yaxnohcah in the Yucatan Peninsula. This area is characterized by a variety of dense tropical rainforest and wetland vegetation zones with limited road and trail access. Twenty-one 100 x 100 m blocks were selected for study, which included examples of several different vegetation zones. A pedestrian survey of transects through the blocks was conducted, recording two types of errors. Type 1 errors consist of cultural features that are identified in the field, but are not seen in the digital elevation model (DEM) or digital surface model (DSM). Type 2 errors consist of features that appear to be cultural when viewed on the DEM or DSM, but are caused by different vegetative features. Concurrently, we conducted an extensive vegetation survey of each block,...

This study proposes a sampling method for ground-truthing LiDAR-derived data that will allow researchers to verify or predict the accuracy of results over a large area. Our case study is focused on a 24 km 2 area centered on the site of Yaxnohcah in the Yucatan Peninsula. This area is characterized by a variety of dense tropical rainforest and wetland vegetation zones with limited road and trail access. Twenty-one 100 x 100 m blocks were selected for study, which included examples of several different vegetation zones. A pedestrian survey of transects through the blocks was conducted, recording two types of errors. Type 1 errors consist of cultural features that are identified in the field, but are not seen in the digital elevation model (DEM) or digital surface model (DSM). Type 2 errors consist of features that appear to be cultural when viewed on the DEM or DSM, but are caused by different vegetative features. Concurrently, we conducted an extensive vegetation survey of each block, identifying major species present and heights of stories. The results demonstrate that the lidar survey data are extremely reliable and a sample can be used to assess data accuracy, fidelity, and confidence over a larger area. Este trabajo propone un método de muestreo a fin de contrastar en el terreno los datos obtenidos a partir de imágenes LiDAR, que permitan al investigador verificar y/o predecir la precisión de los resultados sobre un área mayor. El estudio de caso aquí presentado se centra en el sitio de Yaxnohcah, ubicado en la Meseta Cárstica Central de la península de Yucatán. Está área se caracteriza por presentar una variedad de densos bosques tropicales húmedos y zonas de vegetación de humedal con pocos accesos de caminos y brechas. Para este estudio se seleccionaron veintiún bloques de 100 por 100 metros del área, que comprendió una muestra estratificada del 10 por ciento, e incluyeron ejemplos de varias zonas de vegetación distinta. Se realizó un recorrido de superficie por transectos a lo largo de los bloques, registrándose dos tipos de errores. Los Errores del Tipo 1 consisten de rasgos culturales identificados en campo, pero que no aparecen en el los Modelos Digital de Elevación (MDE) o en el Modelo de Superficie Digital (MSE). Los Errores de Tipo 2 consisten en rasgos que parecen culturales en el MDE o MSE, pero que en realidad son causadas por diferentes tipos de vegetación. De manera concurrente, realizamos un extenso reconocimiento de la vegetación en cada bloque, identificando las principales especies presentes, las diferentes alturas de dosel, así como las características generales de la topografía y los suelos. Los resultados del método de contrastación en el terreno demuestran que los datos lidar son sumamente confiables y es posible utilizar una muestra a fin de evaluar la precisión, la veracidad y la certidumbre de los datos sobre un área mayor.

Without any doubt the making of sketch maps and drawings is a fundamental part of any archaeological enterprise. Even more, such images become the main link with the past; nevertheless is not always possible, due to an array of different factors, making an accurate mapping of archaeological sites. In many cases, the latter is an important factor that might lead to a misunderstanding of the function of sites in the past. In Chinikihá we have been able to make a detailed survey and mapping of architectural features. Our understanding of archaeological processes in Chinikihá has changed during the years depending on the pace of our mapping efforts and new archaeological features were discovered. The availability of a detailed map allows us to come up with new ideas about the use of space, the selection of natural features for urban design, and finally, a better understanding of the role of the city within its broader regional context.