Connectivity of Coupled Hydrologic and Human Systems as the Basis of Resilience in Traditional Irrigation Communities in New Mexico

Abstract

[EN] Changes in land use and water availability are impacting the integrity of traditional irrigation systems and their associated communities worldwide. We designed a study to quantify the components of resilience within coupled hydrologic and human systems in New Mexico USA. We worked collaboratively with three communities in the northern Rio Grande basin to characterize hydrologic, ecological, socio-cultural, land use, and economic system components of linked water and human social systems. Building on component models and quantified resilience examples, we crafted graphical representations of connectivity and resilience. We added data points from around the world gleaned from a research workshop. We found there was more hydrological connectivity with flow paths from irrigation system to irrigated field to groundwater and river; the most important nexus was shallow groundwater recharge. There was more human connectivity with strong connections to land and community involvement; an important nexus was mutualism/social capital. Within the northern New Mexico communities, it appears that hydrological connectivity is associated with higher water availability and even if disconnected due to water scarcity can be restored with renewed water availability. Community connectivity, on the other hand, seems susceptible to long term disruption that self-perpetuates long after the initial stresses are imposed. We compared resilience of the hydrologic and human systems on axes of climate (arid to sub-humid), hydrologic connectivity (between surface water and groundwater and between watershed and river), and community connectedness (between water users and water infrastructure and between community members and water management organizations) including communities from northern New Mexico, Bali, Spain, Morocco, central Chile, Mexico, Ecuador, and southern New Mexico. Hydrologic connectivity was most related to local water availability and climate. Community connectivity seemed to be a function of other variables such as mutualism and local control of governance. Changes in water availability and land use affected communities disproportionately. There appears to be a combination of characteristics that has particularly high resilience: medium aridity allows enough water for hydrologic connectivity yet has enough water scarcity to engender collective community action. Promoting connectivity may be a way to enhance resilience of traditional irrigation communities.