Boletín de la Sociedad Geológica Mexicana / 73 (1) / A171220 / 2021 / 1 Environmental variability during the last three millennia in the rain shadows of central Mexico Variabilidad ambiental durante los últimos tres milenios en las sombras de lluvia de México central Gustavo Olivares-Casillas1, Alex Correa-Metrio2,*, Edyta Zawisza3, Marta Wojewódka-Przybył3, Maarten Blaauw4, Francisco Romero2 ABSTRACT 1 Posgrado en Ciencias del Mar y Limnología, ABSTRACT RESUMEN Universidad Nacional Autónoma de México, Ciudad Universitaria, 04510, Coyoacán,CD- The last three millennia have been characterized Los últimos tres milenios se han caracterizado por osci- MX, Mexico. by global temperature oscillations of around one laciones en la temperatura global alrededor de un grado Celsius degree, and high frequency variability on Celsius, y una variabilidad de alta frecuencia de la 2 Instituto de Geología, Universidad Nacional precipitation. Two main temperature anomalies precipitación. Dos principales anomalías de temperatura Autónoma de México, Ciudad Universitaria, have been reported worldwide, the Medieval han sido reportadas mundialmente, el Periodo Cálido 04510, Coyoacán, CDMX, Mexico. Warm Period (MWP) and the Little Ice Age Medieval (PCM) y la Pequeña Edad de Hielo (PEH), caracterizadas por temperaturas más cálidas y más frías 3 Institute of Geological Sciences, Polish Acad- (LIA), characterized by higher and lower than average temperatures, respectively. Precipitation que el promedio, respectivamente. La variabilidad de la emy of Sciences, Research Centre in Warzaw, precipitación ha estado estrechamente relacionada con 00818, Twarda 51/55, Poland. variability has been mostly associated with El Niño anomalies in the Equatorial Pacific. These las anomalías de El Niño en el Pacífico Ecuatorial. A nivel regional, estos modos de variabilidad han sido 4 global variability modes have been modulated by School of Natural and Built Environment, modulados por factores como la temperatura superficial regional factors such as sea surface temperatures Queen’s University Belfast, Belfast, BT7 1NN, de los océanos y su interacción con las masas continenta- and their interaction with continental landmasses. Belfast, United Kingdom. les. El entendimiento de las respuestas regionales a estas Understanding regional responses to these anom- anomalías ayuda a comprender la respuesta de los ecosis- alies would shed light on ecosystem response to * Corresponding author: (A. Correa-Metrio) temas a la variabilidad global, un elemento crítico para [email protected] environmental variability, a paramount tool for la conservación en vista del cambio climático moderno. conservation purposes on the light of modern En este trabajo se presenta un registro sedimentario de climate change. Here we present a 3,000-year 3000 años del lago Metztitlán, ubicado en la Reserva sedimentary record from Lake Metztitlán, located de la Biosfera en la Sierra Madre Oriental. Se empleo in a Biosphere Reserve under the rain shadow of un análisis geoquímico y cladócero para reconstruir the Sierra Madre Oriental. Cladoceran and geo- dinámicas lacustre en el período de tiempo que abarca el chemical analyses were used to reconstruct lacus- informe. Nuestro registro apunta a sistemas dinámicos trine dynamics through the time period encom- lacustres, asociados con la variabilidad climática global passed by the record. Our record points to highly y regional. En Metztitlán, el PCM estuvo asociado dynamic lacustrine systems, coupled with global con bajos niveles lacustres y una alta torrencialidad How to cite this article: and regional climatic variability. In Metztitlán, de la lluvia, reflejada en picos de alta frecuencia en los Olivares-Casillas, G., Correa-Metrio, A., the MWP was associated with low lake levels and indicadores de aporte detrítico. La PEH estuvo asociada Zawisza, E., Wojewódka-Przybył, M., a high torrentiality of the precipitation reflected con un cuerpo lacustre más extenso, probablemente resul- Blaauw, M., Romero, F., 2021, Environmental in high-frequency peaks of detrital material. The tado de una menor evapotranspiración. En general, los variability during the last three millennia in LIA was associated with an enlarged water body, efectos de la variabilidad climática global se reflejaron en una alta variabilidad de la precipitación y entrada the rain shadows of central Mexico: Boletín probably as a result of lower evapotranspiration. de detríticos (detrital input) en la región de Metztitlán, de la Sociedad Geológica Mexicana, 73 (1), Overall, global climatic variability resulted in high variability of regional precipitation and detrital a su vez asociada con cambios en la morfometría y la A171220. http://dx.doi.org/10.18268/ input in the Metztitlán region, in turn associated profundidad del lago. En nuestro registro resalta la BSGM2021v73n1a171220 with changes in lake morphometry and depth. vulnerabilidad del área a cambios en la temperatura superficial de mar en el Golfo de México, y a cambios en Our record highlights the vulnerability of the la frecuencia de los eventos El Niño. Aunque los efectos area to changes in sea surface temperature of the del cambio climático en el área son inevitables, nuestros Manuscript received: March 16, 2020 Gulf of Mexico, and to changes in the frequency resultados enfatizan la importancia de controlar las Corrected manuscript received: August 25, 2020 of El Niño events. Although the effects of global Manuscript accepted: September 14, 2020 actividades antropogénicas como una fuente adicional de climate change in the region are inescapable, our presión sobre los ecosistemas regionales. results emphasize the importance of controlling anthropogenic activities as an additional source of Peer Reviewing under the responsibility of pressure on the regional ecosystems. Palabras clave: Periodo cálido medie- Universidad Nacional Autónoma de México. val, , pequeña edad de hielo, cladóceros, Keywords: Medieval Warm Period, Little Holoceno tardío, sombra de lluvia, Ice Age, Cladocera, late Holocene, rain Reserva de la Biósfera Barranca de This is an open access article under the CC BY-NC-SA Metztitlán. license(https://creativecommons.org/licenses/by-nc-sa/4.0/) shadow, Barranca de Metztitlán Biosphere Reserve. Environmental variability during the last three millennia in rain shadows of central Mexico http://dx.doi.org/10.18268/BSGM2021v73n1a171220 2 / Boletín de la Sociedad Geológica Mexicana // 7373 (1)(1) // A171220A171220 // 20212021 1. Introduction environments into terrestrial realms through the gradual infilling of the lacustrine basin (Wetzel, Environmental and ecosystem dynamics are 2001). This process is the result of the interaction strongly influenced by the interaction of global and between the lithosphere and the atmosphere, INTRODUCTION regional climatic variability with local processes modulated by climatic and biological factors. at diverse spatial and temporal scales (Delcourt The eutrophication of freshwater ecosystems and Delcourt, 1991; Bradley, 2015). Through the is closely associated with these factors and has Holocene, climatic variability has been expressed been a major topic of interest, as the availability mainly through changes in regional precipitation of water for ecosystem functioning and human regimes, but also through variability in regional consumption is highly dependent on this process. temperatures (Mayewski et al., 2004; Bradley, Eutrophication implies a change on lake trophic 2015). Throughout the Holocene, changes in status of lacustrine environments as a result of the precipitation have been mostly associated with input of exogenic materials producing an increase precessional changes in insolation, generating in autotrophic productivity (Wetzel and Likens, millennial-scale patterns of progressive increases 2000; Wetzel, 2001). This process can be driven by or decreases of precipitation (Haug et al., 2001; natural causes and varies depending on lake mor- Bradley, 2015). phometry, regional climates, and characteristics of Within the last two millennia, the Medieval the catchment basin such as size and vegetation Warm Period and the Little Ice Age represent the cover (Carpenter et al., 1998; Wetzel, 2001). two main changes in global temperatures (Mann et However, during the late Holocene, this pro- al., 2009) that are reflected by sea surface tempera- cess has been accelerated by anthropogenic input tures and therefore by regional hydrological cycles of nutrients derived from intensive and extensive (Richey et al., 2007). The sub-decadal changes in human activities (e.g. Carpenter et al., 1998; the temporal distribution of El Niño anomalies Franco‐Gaviria et al., 2020). Sediment accumula- in the equatorial Pacific have been an additional tions in lacustrine environments contain biologi- source of climatic variability that manifests in cal, chemical, and physical evidence of lake devel- regional hydrologic anomalies across the globe opment through time (Cohen, 2003). The study of (Cane, 2005). The effects of these variability modes this sedimentary evidence offers an opportunity on regional environments depend on mechanisms to understand processes and factors involved in that couple regional and global mechanisms of lake development through time scales beyond the energy redistribution (Bradley, 2015). At a local historic observations. scale, ecosystems represent envelopes that encom- Numerous lakes are distributed across Central pass biological communities and their interactions Mexico, offering the opportunity