It has been thought that the creation of buffer zones might allow logging to take place and still offer some degree of protection to the streams.This idea was praised by logging interests and regarded with no great enthusiasm by environmentalists. The actual science leaves room for some ambivalence and the actual conclusions of working scientists are tentative and deal in specifics rather than generalizations. Newboldt, Erman, and Roby, for example, studied commercially logged and controlled area throughout Northern California. They begin their report by noting that, while there is a conflict between logging and stream maintenance, "...it is difficult to assess and predict the effects on a routine basis ".
They conclude their study by noting that they did observe differences between logged and unlogged streams, but they take great pains to specifically state what those differences were and were not. As an example of their method, consider their conclusions regarding invertebrate density. Higher density was noted in logged than in unlogged areas. They then note that logging shifts the food base, that sunlight, heat, and supply of nutrients are all increased and that these changes can increase primary production and detritus processing. They then state that they cannot confirm an increase in primary production in the logged streams studied, but that such increases could have occurred without being detected by the methods that they made use of. They conclude their article by noting that, with respect to benthos, bottom dwelling organisms, they found that impact was minimized by buffer zones of greater than 30 meters.