Public interest in food systems has grown dramatically, and agricultural economists have important roles to play in contributing to and leading large-scale interdisciplinary studies of the subject. Key topics include understanding food system participants' behaviors and incentives and determining what food systems can and cannot achieve. I review a global food-security project funded by the National Institute of Food and Agriculture that illustrates the interactions between production, distribution, and consumption of food and regional self-reliance, as well as other important areas in which agricultural and regional economists can gainfully apply their tools and methods, including studies of the impacts of local food and network analyses.

Exotic aquatic plant management is a major concern for public reservoir management in many regions of the United States. A study was conducted to measure the effects of alternative aquatic plant management strategies on recreational expenditures and regional economic activity. The study area was Lake Guntersville, Alabama, and the local economy surrounding the lake. Lake Guntersville is one of the largest reservoirs in the Tennessee Valley Authority system. Results suggested that relatively moderate levels of aquatic plant control are associated with the highest levels of recreation-related economic effects on the economy surrounding Lake Guntersville.

Between the 1970s and the 1990s, processed food exports switched from using more skilled labor per unit of output than imports to the opposite. Processed food trade also expanded during this period. More meat and poultry products in processed food trade could explain this switch in skill intensity. Growing meat trade paralleled an urban-to-rural shift in meat processing. Although this could have been a win-win situation for rural areas, many of the jobs related to expanded meat trade benefited commuter and migrant workers because late-1990s jobs slaughtering livestock and processing meat did not appeal to domestic rural workers.

The economic impact of wildlife-associated recreation in the Southeast United States was evaluated using a general equilibrium model. Exogenous demand shocks to the regional economy were based on estimates of expenditures by wildlife recreationists on hunting, fishing, and wildlife watching activities. Counterfactual simulations were carried out, making alternative assumptions about labor and capital mobility and their supply. Without wildlife-associated recreation expenditures, regional employment would have been smaller by up to 783 thousand jobs, and value added would have been $22 to $48 billion less. These findings underscore the significance of regional factor market conditions in economic impact and general equilibrium analysis.

This paper is concerned with integral control of systems with hysteresis. Using an input-output approach, it is shown that application of integral control to the series interconnection ofeither (a) a hysteretic input nonlinearity, an L 2-stable, time-invariant linear system and a non-decreasing globally Lipschitz static output nonlinearity, or (b) an L 2-stable, time-invariantlinear system and a hysteretic output nonlinearity, guarantees, under certain assumptions, tracking of constant reference signals, provided the positive integrator gain is smaller than a certainconstant determined by a positivity condition in the frequency domain. The input-output results are applied in a general state-space setting wherein the linear component of the interconnection is a well-posed infinite-dimensional system.