Concluding remarks: Finding surrogates to understand resilience in relation to tipping points

Agriculture is now one of the main driving forces of global environmental change. Changes to ecosystems are being driven by increased demand for food and fiber to meet the needs of the world’s growing population. Yet our attempts to increase agricultural production have side effects that can lead to critical tipping points in the Earth system. Efforts to increase agricultural production have often focused on agricultural production to the exclusion of other important ecosystem functions that sustain ecosystem services, including habitat for pollinators, high quality water, and places to recreate. Ignoring these ecosystem functions also appears to decrease ecosystem resilience, increasing the likelihood of crossing “tipping points”, thresholds beyond which the past response of the system no longer predicts the future. Crossing tipping points can produce sudden and dramatic shifts in the supply of ecosystem services. Examples include freshwater eutrophication through fertilizer runoff, grazing’s impact on soil degradation due to changes in vegetation pattern, and changes in climate from alterations of water flows from land to atmosphere. While tipping points in the food-water system have been monitored at small scales, there have been few synthetic attempts to understand and model large-scale regime shifts. Such understanding is necessary to develop agricultural and development policies that sustain rather than degrade the biosphere. In this session, the presenters have identified potential tipping points related to water and agriculture that could have major consequences for the future of ecosystem services globally.  They have assessed potential tipping points mediated by agriculture and water, as well as discussed new methods to detect, assess, and avoid any undesired regime shifts. Based on the talks in the session and on literature review, I will elucidate emerging lessons on how to how to use surrogates to predict and model tipping points in the food-water system.