Food, what we eat, where it comes from, how it's produced and distributed, has, to put it mildly, significant environmental consequences.
The millennium ecosystem assessment estimates that as much as one quarter of the Earth's surface has been modified for agriculture, a key driver in the loss of biodiversity.
There is now up to six times more water stored behind dams than which flows naturally in rivers. Over 70% of global freshwater use is for agriculture. Global flows of nitrogen and phosphorus have more than doubled in the past 50 years.
A 2012 report in Nature estimated the global food system, including food production, storage, packaging, transportation, retail and waste, accounts for one third of human-related greenhouse gas emissions.
The message is that if we are going to address global environmental change, we need to think about food and agriculture differently.
This is not new.
In 1977, to take one example, Frances Moore Lappe and Joseph Collins suggested in their book Food First: Beyond the Myth of Scarcity that grappling with food issues provides the most useful tool in making sense out of our complex world.
The explosion of local food initiatives since that time suggests that many have taken to using food as a lens to examine our complex relationships with each other and with the environment.
Internationally, local food initiatives have emerged out of wide-ranging concerns about health, environment and local economies and potential alternatives take their cue from the 100-mile diet, organic food or health and equity.
Others are motivated by a desire to re-localise economic activity and preservation of farmland, the family farm and farm employment. Still others are driven by concerns of peak oil, climate change and community resilience.
There are inspiring examples of organisations around the world that have made significant inroads in raising awareness about where our food comes from, how it is produced, and how waste is addressed.
They have also influenced markets, generated new business opportunities and shifted agricultural production from export to satisfying local needs.
These concerns are reflected in responses to a survey of people engaged in local food issues in Dunedin.
Respondents indicated that food security and social justice, self-sufficiency, climate change and local economic development were the primary motivations for their interest.
There is a wide range of formal and informal local food initiatives operating in Dunedin, including local producers and farmers market vendors, retailers, community gardens and orchards and organisations that are focused on improving food literacy, public health or providing training in food production.
The primary aims and objectives of these organisations can be grouped under efforts to raise awareness about local food (25%), increase local production of food (19%), improve access to food and address social justice (18%) and to support organic production (14%). While these initiatives are tiny when compared to global and industrial food systems, they do represent visible examples of thinking about food and agriculture differently in the Dunedin context.
The fact that they exist, are growing in number and are part of a broader global movement to address sustainability in the context of food suggests that these seemingly small initiatives will help us all to question how we are engaged with the food system.
Sean Connelly is a lecturer in the department of geography, University of Otago.
Each week in this column one of a panel of writers addresses issues of sustainability.