lations from the toxic effects of pollution and (2) protecting natural areas from human impacts. Both priorities reinforce the view that farms are separate from the natural environment, which must be protected from agriculture. In Europe and some other parts of the world, farms are often seen as an integral part of the natural environment that should be protected (Frewer et al. 1997, Durant et al. 1998). Environmental protection can therefore encompass the protection of a partially domesticated countryside where appropriate farming techniques can foster biodiversity. There certainly are exceptions to this generalization because many U.S. citizens are concerned about the effects of agricultural practices on the flora and fauna of farms, and there are agricultural production regions in Europe that are as thoroughly industrialized as any in the United States (Durant and Gaskell, in press). It is nevertheless important to bear in mind that contrasting cultural values influence the way that different people understand the relationship between agriculture and environment, and this in turn influences their judgment of what constitutes a threat to the environment (Knowles, in press).
The molecular techniques for producing transgenic agricultural crops that came to fruition in the late 1980s arrived on a scene in which advocates for agricultural technology were already prepared to embrace them. Biotechnology was greeted by these advocates as a means of increasing agricultural efficiency, decreasing world hunger, and ameliorating environmental damage caused by previous agricultural technologies. But at the same time, critics of agricultural technology were prepared to view these new techniques with skepticism. Their skepticism was based both on their negative assessment of postwar technologies that contributed to the boom in agricultural productivity and their judgment that the science which could identify the environmental risks of these new technologies was not being adequately supported.
As farming enters the twenty-first century it faces a world in which there is increasing public pressure on governments to more actively protect the environment and conserve biological diversity. Currently, much public concern regarding agriculture and the environment is focused on the potential impacts of transgenic plants. However, it is clear that many of the environmental effects that could result from this specific technology could also occur due to changes in other agricultural technologies and farming practices (see “Environmental Effects of Agroecosystems” below). Concern over the impact of transgenic plants on the environment has led world governments to reassess the standards by which they judge what constitutes a significant negative effect of agriculture on the environment. For example, it is clear that environmental standards being developed for transgenic plant cultivars consider impacts that were rarely even measured when novel conventional crop cultivars were introduced