This study employed a GIS-based use-analysis on a network of recently mapped pre-Columbian earthworks lying on the west side of a Bolivian floodplain. This wetland region, called Llanos de Mojos, is home to many different types of artificial mounds that served different roles for the ancient communities who constructed them thousands of years ago. This new set of features, which was mapped by volunteers of the Proyecto Sistemas Informaticas Geograficas y Arqueologicas del Beni (ProSIGAB) was purported to be a network of fish weirs, linear earthworks built in rivers or floodplains that are designed to trap fish by exploiting seasonal floodwaters. This identification was based on their similarities with the Baures Hydraulic Complex on the east side of Mojos (Erickson 2000; McKey et al. 2016; Blatrix et al. 2018). Classification procedures made use of the features' physical attributes and relationships with other landscape features to identify them not just as fish weirs, but multi-use structures that connected infrastructure, impounded water, and trapped fish. When understood together with nearby forest island settlements, neighborhoods of agricultural fields, and drainage features, it is argued these earthworks played a substantial role in the lives of past inhabitants, demonstrating their ingenuity by fulfilling multiple functions in a complex anthropogenic landscape.

Modern agricultural systems have been criticized for their detrimental effects on the environment and a general emphasis on crop yield rather than long-term sustainability. Traditional forms of agriculture may provide case-specific examples of sustainable alternatives for contemporary societies. In the seasonally inundated savannas of the Llanos de Mojos, pre-Columbian Indians piled earth into ‘large raised field platforms’ elevated high enough above the floodplain to allow crops to grow. Archaeological evidence indicates that raised field agriculture supported much larger populations than those found in the Beni today. The examination of satellite imagery has revealed more than 40,000 individual fields spread across an area of approximately 7,500 square kilometers. This study created a digitized map of large raised fields to search for spatial patterns in their distribution. A GIS analysis was conducted in which fields were distributed into organizational groups based on characteristics such as proximity and orientation to cardinal direction. These groups represent potential ‘social units’ involved in the organization of labor required to construct raised fields. This study demonstrated the consistent presence of these units throughout the entirety of the agricultural system. Patterns in the distribution of these groups allowed the study area to be divided into two distinct regions representing a larger scale of organization within a seemingly uniform system. A transitional zone between these two regions was identified on the river Omi, providing a clear area of interest to target in future archaeological excavations. Further archaeological investigations of raised field agriculture have the potential of demonstrating the overall productivity of the system as well as how it was incorporated into the social systems of those who managed it.