Since the mid-1900s, humans have been exerting an ever-increasing impact on the global nitrogen cycle. Human activities, such as making fertilizers and burning fossil fuels, have significantly altered the amount of fixed nitrogen in the Earth's ecosystems. In fact, some predict that by 2030, the amount of nitrogen fixed by human activities will exceed that fixed by microbial processes (Vitousek 1997).
1 Faux leather is man made fabric (usually polyester) that has been treated with wax, dye, polyurethane, or PVC (polyvinyl chloride) for color and texture that feel like real leather at a much lower cost.
Patent leather is leather that has been finished with chemicals that give it a shiny, reflective surface. It is usually black, and has long been popular for dress and dancing shoes. Most stages of the preparation of patent leather are the same as for other fine quality leathers.atent leather is usually light and thin, and usually derived from a calf or a kid. Today, however, patent leather can be made from any kind of hide, and need be of no finer quality than most shoe leathers.