By Contributing Columnist Richard Olsen-Harbich Most people understand the general concept of “organic,” especially as it applies to the food we eat. But lately in the Long Island wine community, the “buzz” is all about sustainability. The question on a lot of people’s minds is—what exactly does this mean? The concept of sustainable agriculture grew out of the early organic movement and became fine tuned during the late 1980s. In 1989, the American Agronomy Society adopted the following definition for sustainable agriculture: "A sustainable agriculture is one that, over the long term, enhances environmental quality and the resource base on…