The transition from climate-driven to human-driven agriculture during the Little Ice Age in Central Spain: Documentary and fluvial records evidence

Abstract

Knowledge about the relative impact of climate and socio-economic factors on agriculture is still not well known as they change in space and time. Social researchers stress the role of endogenous (societal, economical, etc.) factors whilst physical/natural scientists focus on the role of climate on land use and land cover change, but the latter do not usually focus on human dynamics.Through the analysis of proxies of land cover, sediment yield (erosion) and salinity changes from sediments in a fluvial wetland in central Spain and documentary evidence collected from the 16th century onwards, it becomes clear that climate impact on farming has changed during this period. Thus, until ca. 1725 CE, agriculture production in central-southern Spain followed the cycles and trends of rainfall at the annual, multiannual and decennial time scales. From that time onwards, production began to show discrepancies with climate, with high production cycles associated with dry periods being common and a sustained productivity that was independent of climate trends and it must be related to socio-economic changes.This change from climate-driven to human-driven agriculture can be seen in other areas of the Iberian Peninsula but at different times that vary from the first half of the 17th century until the first half of the 18th century. These different times can be attributed to diachronous changes in the Little Ice Age phases and local and regional differences in economic factors (such as proximity to commercial routes, development of markets) and their evolution, as supported by the different information sources.