Sustainable Ecological Agriculture in China: Bridging the Gap Be ...

Ecosystem changes are generally a result of the combined effects of natural dynamics and a multitude of economic decisions. Since the benefits of the expropriation of matter and energy are mostly private whereas the costs are largely social, there is a tendency to overexpand the scale of the economy or to ‘allocate’ too much of the matter-energy of the total ecosystem to the economic subsystem (Costanza & Daly, 1992). Ecosystems are undervalued and overexploited when ecological and economic systems are not tightly coupled. Moreover, the processes of market extension and economic globalisation have weakened the bonds between humanity and nature (Tisdell, 1990). Consequently, natural landscapes have been converted into human-modified cultural landscapes (Naveh, 2000). This expanding human presence is having marked impacts on the world's ecosystems. Human activity is disrupting ecological life-support systems to the extent of approaching the ‘thresholds of human survival’ (WCED, 1987, p. 33). Our world is now moving from a demand-driven economy with perceived unlimited natural resources to a natural resource–limited economy (Daly, 1992). In other words, the evolution of the economy has passed from an era in which human-made capital was the limiting factor in economic development to an era in which the remaining natural capital has become the limiting factor (Costanza et al., 1997).

Biophysical Limits to Economic Activity

The starting point of an ecological economics approach is recognising the open character of the economic sphere in which economic activities take part and affect the social and natural environment. Traditionally, a simplified view of the economic process places the economy in an empty space with no connections to the natural world. The concern