Endogenous growth of population and income depending on resource and knowledge.

PIP: This study focuses on the dynamic, endogenous, nonlinear interactions between the economy, population growth and the environment. Literature on endogenous growth theory was reviewed and the 3-sector demoeconomic model was provided as the analytical framework for the study of sustainable development through the integration of population growth, resource use and economic growth. The model is described in such a way that the labor force is considered as a free migrating variable among three different kinds of employment: the primary sector, which harvests a renewable resource, the secondary or industrial sector, and the tertiary sector, which is responsible for the accumulation of the stock that represents a public good for all three sectors. Presented in this paper is a nontechnical outline of the model that describes the economic, demographic, and environmental interactions considered. Also given are dynamics, market equilibrium and dynamic feedback rules. Furthermore, numerical analysis of the model quantifying the resulting time paths of the variables involved is included. The dynamics are simply the outcome of the nonlinear interactions of the demographic, economic and environmental modules. Numerical studies have also shown that the system variables move with different velocity. Technology and population can generally be regarded as slow moving variables by comparison with resources.^ieng

Endogenous population growth and the exploitation of renewable resources.

The authors consider a demo-economic model where the economy consists of two sectors ("hunting and farming" and "industry"), and both sectors depend directly or indirectly on the explanation of a renewable resource. The primary sector harvests a renewable resource (fish, corn, or wood) which is used as the input into industrial production, the secondary sector of our economy. Labor is divided up between these two sectors under the assumption of competitive labor markets. A system of two nonlinear differential equations for the resources and the population is studied by phase space analysis. Using the Hopf bifurcation theorem, the authors obtain two different routes to limit cycles and prove numerically the existence of a stable Malthusian limit cycle.