Social-ecological participatory observatory sites in arid northern Mexico: co-definition of shared space and future challenges of drought under climate change

Abstract

Drylands social-ecological systems are one of the most extensive, diverse, yet highly vulnerable social–ecological systems of our planet Earth. Aridity and drought patterns cause increasing pressure on land and water resources and are some of the largest global and local environmental and social change problems and thus are a challenge for science and society. Drylands cover approximately 65% of the Mexican territory; over 60% of the total population inhabit these areas. Recent scientific consensus suggests that to potential solutions to land degradation need to be identified and implemented within the context of local environmental, social, economic and political conditions. At the same time, the complexity of drought risk demands cross-sectoral policies accounting for regional diversity, leveraging local knowledge and promoting communities' engagement. In this research, our study sites, the Social-ecological participatory observatories (OPSEs) lie along a west–east transect in northern Mexico drylands. The OPSEs are a social-ecological innovation and provide a space for the consolidation of formal and informal alliances for sustainability through learning communities that share diverse knowledge, technologies, and innovations. As a result of a survey applied to actors of various sectors linked to the OPSEs, priority issues were defined, including climate change, drought, and water scarcity. In this research, the general objective was to analyze the social-environmental value linked to shared land by multiple stakeholders as a basis to co-define the spatial boundaries of social-ecological systems and analyze potential future changes in precipitation and the potential occurrence of droughts under climate change conditions in the context of the OPSE network divided in three chapters. Chapter one showed that the valuation of land by multiple stakeholders by identifying and mapping different meaningful places in the OPSE Mapimí can be integrated to generate socio-economic variables that are not available in vectorial format and combined with biophysical variables allowed the spatial delineation of a Social-ecological system and the estimation of social-ecological units within the OPSE Mapimí. This delineation is dynamic and flexible and subject to updates and re-evaluations, as it is based on the perception, intuition, experience, interest, knowledge and judgment of different stakeholder groups, which are highly experienced and knowledgeable about the local and current social-environmental conditions. Chapter 2 highlights that for an adequate characterization of drought conditions, good quality precipitation data are indispensable. This chapter examined how the rainfall gauge network in Mexico’s drylands that is highly heterogeneously distributed and frequently with incomplete datasets, can be compensated by information derived from global precipitation datasets. Based on the performance of five global precipitation datasets, we suggest using CHIRPS and AgERA5 climatic data to fill gaps of observational rain gauge information. Chapter 3 examined the occurrence (frequency, severity and duration) of historical (1981-2010) and future (2041-2100) meteorological droughts at time scale of 12 months for the OPSEs network using the Standardized Precipitation Index (SPI). Likewise, the perception of the concept of drought and adaptation measures were analyzed in the OPSE Mapimí. Results suggest that in the near (2041-2070) and far (2071-2100) future, an increase in the average annual precipitation is projected for the OPSE network. In general, drought conditions at the 12-months time scale for the near future, presented less frequent events with a decrease in its duration. In the OPSE Mapimí, the drought concept mostly found to be linked with issues related to rainfall (no rain) and vegetation (no forage). The years 1951, 1953, 1970, 1972, 1977, 1978, 1984, 1986, 1988, 1989, 1990, 1995, 1997, 1998, 2001, 2002, 2008, 2011, 2012 and 2019 were identified as the most important drought events since they affected their living conditions. The years 1958, 1987, 1990 and 2010 were identified as the wettest years, causing flooding in the ejido Laguna de Palomas. Changes in the weather were generally recognized by the respondents (more heat and less rain), if not expressed as “climate change”. Adaptation measures to face drought in case of cattle raising include selling some animals to maintain the remaining animals or cutting and burning prickly pear as an alternative food source for livestock. The salt producers and ecotourism people were temporarily employed or received economic support from relatives. One of the innovations of this research is that the process promotes an exchange of information (scientific and non-scientific) and is approached from two different perspectives: one based on observation and measurement (e.g., relief morphometry, land use/cover, etc.) and a phenomenological one, based mainly on people's experiences (mapping of significant places from valuations of space by multiple sectors and the deep understanding of the concept drought. Hence, this research represents a transferable and replicable approach. The OPSE model, in a time frame of 4-5 years (to be defined), is observed to have important implications for future transdisciplinary research that could focus on collaborative social-environmental governance with the important focus on water governance, climate modeling, community resilience and novel questions that could lead to the development of more sustainable approaches for the adaptive and integral management of Mexico’s drylands.