This summer, I’ll be presenting a paper at the bi-annual conference of the International Society for Ecological Economics (ISEE) in Bremen, Germany.  I will also be contributing to a paper that will be presented at the International Input-Output Association (IIOA) conference in Sydney, Australia in June.  Below is information about my submission to the ISEE, and for more info on the conference  For information on the IIOA conference go to


Population Growth, Increasing Affluence, and Adequacy of Food Supply


Faye Duchin and Nat Springer

Rensselaer Polytechnic Institute, Troy, NY

Subject / Theme

Long Presentation
Topics: Land Use, Ecology, Sustainable Development
Keywords: Agriculture, Input-Output, Diets, Water


Growing populations and increasing affluence in Asia and other parts of the world economy will require substantial increases in production and in resource availability. In this paper we focus on the increases in arable land, fresh water, phosphates, capital and labor that will be required to feed the populations anticipated for 2050. A set of scenarios explores the implications of changes in diets and in agricultural technologies for production and trade in agricultural products, the prices of these products, and scarcity rents on factor inputs.

A large number of studies have generated estimates of changes in trade and product prices from within a general equilibrium framework. Alternatively, this analysis builds on previous research on agriculture using the World Trade Model (WTM), a multi-regional input-output model that determines production, trade and prices to satisfy given final demand by minimizing factor use subject to limited factor endowments. An earlier study of the future food supply applied the WTM to a database with about a dozen regions and a dozen sectors and focused mainly on availability of different qualities of land (Julia and Duchin, 2007). The present study will make use of the new EXIOPOL database, an environmentally-extended input-output database of the world economy with several dozen regions, over a hundred sectors, and explicit representation of water for irrigation and of phosphates for fertilizer, two factors that are widely anticipated to be in increasingly limited supply by 2050. It also makes use of a model extension to track an average unit of a scarce resource, such as fresh water, from a region where it is extracted through its chain of intermediate uses to those regions where it is embodied in consumer products.

Julia, R. and F. Duchin. 2007. “World Trade as the Adjustment Mechanism of Agriculture to Climate Change.” Climatic Change, 82(3-4): 393-409 (June).