The intersection of expanding human development and wildland landscapes—the “wildland–urban interface” or WUI—is one of the most vexing contexts for fire management because it involves complex interacting systems of people and nature. Here, we document the dynamism and stability of an ancient WUI that was apparently sustainable for more than 500 y. We combine ethnography, archaeology, paleoecology, and ecological modeling to infer intensive wood and fire use by Native American ancestors of Jemez Pueblo and the consequences on fire size, fire–climate relationships, and fire intensity. Initial settlement of northern New Mexico by Jemez farmers increased fire activity within an already dynamic landscape that experienced frequent fires. Wood harvesting for domestic fuel and architectural uses and abundant, small, patchy fires created a landscape that burned often but only rarely burned extensively. Depopulation of the forested landscape due to Spanish colonial impacts resulted in a rebound of fuels accompanied by the return of widely spreading, frequent surface fires. The sequence of more than 500 y of perennial small fires and wood collecting followed by frequent “free-range” wildland surface fires made the landscape resistant to extreme fire behavior, even when climate was conducive and surface fires were large. The ancient Jemez WUI offers an alternative model for fire management in modern WUI in the western United States, and possibly other settings where local management of woody fuels through use (domestic wood collecting) coupled with small prescribed fires may make these communities both self-reliant and more resilient to wildfire hazards.

We convened a workshop to enable scientists who study water systems from both social science and physical science perspectives to develop a shared language. This shared language is necessary to bridge a divide between these disciplines' different conceptual frameworks. As a result of this workshop, we argue that we should view socio-hydrological systems as structurally coconstituted of social, engineered, and natural elements and study the "characteristic management challenges" that emerge from this structure and reoccur across time, space, and socioeconomic contexts. This approach is in contrast to theories that view these systems as separately conceptualized natural and social domains connected by bi-directional feedbacks, as is prevalent in much of the water systems research arising from the physical sciences. A focus on emergent characteristic management challenges encourages us to go beyond searching for evidence of feedbacks and instead ask questions such as: What types of innovations have successfully been used to address these challenges? What structural components of the system affect its resilience to hydrological events and through what mechanisms? Are there differences between successful and unsuccessful strategies to solve one of the characteristic management challenges? If so, how are these differences affected by institutional structure and ecological and economic contexts? To answer these questions, social processes must now take center stage in the study and practice of water management. We also argue that water systems are an important class of coupled systems with relevance for sustainability science because they are particularly amenable to the kinds of systematic comparisons that allow knowledge to accumulate. Indeed, the characteristic management challenges we identify are few in number and recur over most of human history and in most geographical locations. This recurrence should allow us to accumulate knowledge to answer the above questions by studying the long historical record of institutional innovations to manage water systems.

No abstract

No abstract

Adapting our infrastructure and institutions to climate change is a crucial dilemma for modern society. Archaeologists should be well positioned to address this issue with examples from the past. Yet, too often when we find that cultural changes are synchronous with climate variation, such as abandonment of a region during a drought, we advance causal arguments to what may merely be correlations. I argue that identifying proxies for resource management in the archaeological record, particularly for resources managed by collective action and vulnerable to climate change, can help to address this problem. To test this approach I studied water management practices of Ancestral Pueblo communities living on the highland mesa-tops of the Jemez Mountains of New Mexico. Between AD 1100-1700 cultural histories across this region diverged. Ancestral Towa communities of the Jemez Plateau sustained high populations until Spanish removal in the 17th century. The adjacent Pajarito Plateau was nearly completely depopulated by ancestral Tewa and Keres communities by the early 16th century. Archaeologists hypothesize that droughts were a factor in pushing people off the Pajarito Plateau, yet the endurance of communities on the Jemez Plateau is unconsidered. Mesa-top communities in both regions constructed artificial water reservoir features, which historical Pueblo communities managed as common pool resources. I hypothesize that these archaeological features reflect collective action decision-making for managing water, a resource vulnerable to scarcity on these mesa-tops during droughts, and that decisions made about water management influenced the long-term sustainability of Ancestral Pueblo communities. Through diachronic socio-hydrological modeling, I identify how climate variation influenced feedbacks between resource users, water infrastructure, and hydrological systems. I conducted modeling of paleohydrological system responses to droughts, direct geoarchaeological investigations of fifteen reservoirs at nine Ancestral Pueblo villages, and geospatial analyses of water access. My hydrological modeling found that the Pajarito Plateau is more vulnerable to hydrological droughts than the Jemez Plateau. My geoarchaeological investigations found that communities on the Jemez Plateau built reservoirs before droughts when populations were low, and that reservoirs were used and maintained through their entire occupation histories. By contrast, communities of the Pajarito Plateau built reservoirs in the early 1300s when hamlets were coalescing into villages at the peak of regional populations. All of the reservoirs on the Pajarito Plateau, as well as many of the villages with reservoirs, were then abandoned by the mid-1400s. Through least cost analyses from hundreds of water sources to thousands of archaeological sites I found that water costs became much higher during droughts on the Pajarito Plateau, which was further exacerbated by the pooling of resources (and risks) in aggregated communities. Therefore, it cannot be ruled out that an over-reliance on collective action approaches to water management made communities on the Pajarito Plateau more vulnerable to hydrological droughts than communities on the Jemez Plateau. My work shows how archaeological research into resource management, employing earth science methods and common pool resource theory, contributes to dialogs surrounding adaptations to climate change.

No abstract

The travertine-lined irrigation canal networks of the Tehuacán Valley, Mexico allowed pre-Hispanic indigenous communities to overcome risks of crop failures in an arid setting. Segments of these systems are still in use today, therefore understanding when and how these irrigation networks functioned allows us to identify which attributes of a coupled socio-hydrological system are important for maintaining the long-term resilience of irrigation systems in drylands. This paper summarizes the results of an interdisciplinary study of this prehispanic irrigation network involving mapping, radiometric dating, and diatom analyses of materials extracted from the travertine lined canals. All of the canal networks were functioning by ca. 2000 BC, at the transition from the Late Archaic to the Formative period, which is before archeological evidence for widespread community-level aggregation. Provocatively, some canals are potentially as old as 6000–4000 BC, which would mean that hunter-gatherers initiated irrigation coevally with the introduction of semi-domesticated maize, a tropical species which would require supplemental water in this arid context. The canals both facilitated agricultural intensification and enhanced the distribution of aquatic ecosystems. The resilience of these systems to their unique spring dependent context demanded frequent maintenance and the integration of multiple canal networks to mitigate geohydrological vulnerabilities of reduced discharge. These conditions set up a long-term reciprocal dynamic between people and water in the Tehuacán Valley. The results demonstrate that rigidities inherent to tightly coupled socio-hydrological systems in dryland settings were overcome by institutional arrangements first developed by indigenous communities deep in prehistory.

No abstract