Syndromes of Production: an Emergent Property of Simple Agroecosystem Dynamics

摘要

Ecological and economic forces are combined in a model of agroecosystem dynamics. Functions relating (1) cultivation intensity to regional yield, (2) regional yield to unit price, and (3) unit price to cultivation intensity are composed into a single function relating production and/or prices from one time period to another. The combination of ecological and economic dynamics are thus seen as codeterminants of two possible "syndromes of production". One syndrome includes high product prices, market volatility, ecological decline, high cultivation intensity and low overall supply while the other syndrome includes low prices, stable markets, ecologically benign, low cultivation intensity, and high overall supply. The dynamical consequences of the model include stable points, permanent oscillations and chaos, either in the region of one or the other syndrome or periodically changing from one syndrome to the other.