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There has been an explosion of interest globally in food security and sovereignty with the increasing awareness of the limitations and negative consequences of the agri-industrial food system on human health, physical environment and social equity and in the escalation of anthropogenic climate change. Within this context, this paper focuses on how social and solidarity enterprises based on locally based food systems are addressing environmental, social and economic issues. These enterprises are meeting the need for food security and food sovereignty. This emergent social economy in the food sector is contextual and place-based and has the potential to be more resilient by building on long-established traditional practices and the protection of food crop seeds that carry the genetic diversity so critical to adaptation to unforeseen future global circumstances. These challenges to the dominant food system and its economic underpinnings present numerous opportunities to grow and expand the social and solidarity economy and enhance community food sovereignty and security throughout the world. The paper concludes by proposing a series of questions as a catalyst for state-civil society dialogue to develop public policies for the social and solidarity economy.

Three case studies are used to exemplify the wide variety of controlling factors that combine to influence the development of modern turbidite systems, and how these vary with location and time. For example, Cascadia Basin in the Pacific Ocean off western North America, which is underlain by the Cascadia Subduction Zone, exhibits the dominant tectonic control of earthquake triggering for turbidity currents, the increased sediment-supply effects of the Mt. Mazama catastrophic volcanic eruption in 7626 yr B.P., the glacial climatic and sea-level lowstand control on rapid turbidite-system growth rates, and the recent anthropogenic control that reduces sediment supply rates. Lake Baikal in Russia shows how the rift-basin tectonic setting controls the number and type of sediment input points, the amount of sediment supply, and the consequent types of turbidite systems developed along different margins of the Baikal basin. Pleistocene glacial climatic changes, without changes in lake base level, causes increased sediment input and the rapid growth rate of Baikal turbidite systems that is three to five times greater than that during the Holocene interglacial climate. The Ebro turbidite systems in the northwest Mediterranean Sea exhibit control of system types by the Messinian salinity-crisis lowstand, of channel locations by oceanographic current patterns, and of sediment-supply increase by glacial climatic changes as well as recent decrease by anthropogenic changes.Both active-margin and passive-margin settings have some common controls such as climatic and sea-level changes, and develop similar types of turbidite systems such as base-of-slope aprons, submarine fans, and deep-sea or axial channels. Each margin also has specific local controlling factors, for example the volcanic events in Cascadia Basin, glacial climatic without erosional base-level control in Lake Baikal, and the Messinian extreme lowstand in the Mediterranean Sea. Comparison of modern turbidite systems points out new insights on external controls such as importance of: (1) earthquakes for triggering turbidity currents on active tectonic margins, (2) equal or greater Pleistocene climatic control compared to lowered base level for sediment supply, (3) direct glacial sediment input that results in doubled proximal channel size, (4) greatly reduced deposition rates in drained compared to ponded turbidite basins, (5) importance of ocean currents on location of turbidite systems and channel development, and (6) anthropogenic effects from river damming during the last century that sometimes reduces present sediment supply to turbidite systems by orders of magnitude.

The Mediterranean Sea hosts two subduction systems along the convergent Africa-Eurasia plate boundary that have produced strong ground shaking and generated tsunamis. Based on historical descriptions and sedimentary records, one of these events, in 365 CE, impacted a broad geographical area, including tsunami evidence for distances of 700–800 km from the source event, qualifying it as a ‘megatsunami’. Understanding how megatsunamis are produced, and where they are more likely, requires a better understanding of the different secondary processes linked to these events such as massive slope failures, multiple turbidity current generation, and basin seiching. Our sedimentary records from an extensive collection of cores located in distal and disconnected basins, identify turbidites which are analyzed using granulometry, elemental (XRF), micropaleontological, and geochemical data in order to reconstruct their coastal or marine source. The results show that the 365 CE basin floor sediments are a mixture of inner shelf and slope materials. The tsunami wave produced multiple far-field slope failures that resulted in stacked basal turbidites. It also caused transport of continent-derived organic carbon and deposition over basal turbidites and into isolated basins of the deep ocean. The composition of sediment in isolated basins suggests their deposition by large-scale sheet like flows similar to what has been caused by the Tohoku earthquake associated tsunamis. This is significant for rectifying and resolving where risk is greatest and how cross-basin tsunamis are generated. Based on these results, estimates of the underlying deposits from the same locations were interpreted as possible older megatsunamis.