Evolution of ancient farming systems and demography in the volcanic highlands of Zacapu: A model drawn from Geoarchaeology and archaeogeography

Abstract

Among the numerous archaeological remains that recent LiDAR flights revealed in Guatemala and Mexico, agrarian features are the most abundant. Archaeologists today are compelled to revise their paradigms in terms of methodology and assessment of environmental appropriation for agriculture. The Malpaís de Zacapu in west Mexico is one example. Besides the discovery of a substantial Epiclassic occupation near the well-documented Postclassic urban centers of the area, LiDAR imagery brought to light a deeply modified agrarian landscape and thereby dramatically changed our understanding of human settlement in this lava flows complex. Focusing on the northern part of the Malpaís, this study uses archaeogeographical and soil science methods to assess ancient farming systems and their evolution. We updated the archaeological and soil maps of the area, combining traditional field survey techniques and LiDAR-derived data interpretation. This allowed us to identify residential zones and a wide range of associated agrarian features adapted to the variety and agronomic challenges of volcanic soils. We further implemented a production-consumption model to reconstruct agricultural strategies from the Epiclassic to the Middle Postclassic period, from self-reliance to the necessity of supra-local agricultural inputs, possibly foreshadowing the Tarascan state tribute system.

Ancient Agriculture on Lava Flows: Using LiDAR and Soil Science to Reassess Pre-Hispanic Farming onMalpaísLandforms in West Mexico

“…All of these agrarian features display morphologies adapted to the specific geopedologic contexts in which they were constructed. A detailed typology has been published elsewhere (Dorison 2020; Dorison and Siebe 2021).…”

“…In that regard, geosciences, such as geomorphology, soil science, or geology, whose relevance to interpreting archaeological data is well-established (Goldberg and Macphail 2006; Holliday 2004; Nicosia and Stoops 2017), can prove very helpful to unraveling the anthropogenic from the “natural” in LiDAR-derived images (Golden et al 2016). Approaches combining LiDAR, archaeology, and geosciences are especially beneficial for studying agriculture in its spatial aspects and offer new perspectives to better understand rainfed cultivation, whose material traces are difficult to detect in the field (Dorison 2020; Dorison and Siebe 2021).…”

Holocene volcanic eruptions of the Malpaís de Zacapu and its pre-Hispanic settlement history

“…The name Malpaís de Zacapu (malpaís means "badland" in Spanish, while tzacapu means "stony place" in Purepecha) refers to the lava flow surfaces made of rock fragments mostly devoid of soil, which are unsuitable for agriculture. One particularity of the Malpaís de Zacapu is that its volcanic structures are geologically very young (Mahgoub et al 2018;Reyes-Guzmán et al 2018) and these badlands were inhabited by pre-Hispanic populations during the Milpillas phase (A.D. 1200-1450; Arnauld and Faugère-Kalfon 1998; Dorison 2019;Faugère 2006;Michelet 1993;Michelet et al 1989;Migeon 2016;Pereira et al 2021;Forest 2023). The Malpaís de Zacapu is defined as a spatiotemporal monogenetic cluster because it is formed by four monogenetic volcanoes that erupted in a restrained area (<40 km 2 ; Figure 4) and over a relatively short period of time (less than 2,500 years; Reyes-Guzmán et al 2018).…”

“…During the Lupe phase, the southern lacustrine basin was still inhabited by local people, but the occupation expanded to the entire region. An important cluster of monumental and residential sites developed at the northwest edge of the western ZLB (on the surface of Las Flores, Las Minas, Las Florecitas-El Malpaisillo, and Mesa del Bolsón volcanos; see Figure 4; Dorison 2019;Pereira et al 2023). This area shows an important economic development based on the intensive exploitation of the volcanic environment for agriculture (Dorison 2019;Dorison and Siebe 2023), and mineral resources (Quezada and Darras 2023).…”

“…Recent studies (Mahgoub et al 2018;Reyes-Guzmán et al 2018 have elucidated the age and dynamics of the eruptions, as well as the rheological characteristics of the different lava flows of the Malpaís de Zacapu and their emplacement durations. Here we present a summary of their findings and relate them to the archaeological record to better constrain the periods of occupancy and lifestyle adaptations of the people who lived on the lava surfaces and their surroundings (Arnauld and Faugère-Kalfon 1998;Arnauld et al 1993;Dorison 2019;Faugère 2006;Michelet 1993; Michelet et al Volcanic Field (outlined in red), showing lakes (in blue; ZiL = Zirahuén Lake, PL = Patzcuaro Lake), the Zacapu lacustrine basin (ZLB, in green), the main Holocene volcanoes mentioned in this study (red triangles, black font), major faults (black lines), principal cities (black polygons and italic black font), and archaeological sites (pyramid symbols and red font). The yellow quadrangle indicates the western Zacapu lacustrine basin area presented in Figure 4.…”