ABSTRACT
This chapter begins disturbance as any process or punctuated event that removes or reduces microbial biomass. It reviews methodology, biochemical in character and with specific focus on lipids, for detecting disturbance in sedimentary microbial communities. The chapter involves tracking the dynamics of microbial biomass following the disturbance. It determines biomass and leaves to the reader the task of assimilating the controversial subject of growth-rate determinations. With the caveat that it refers to the community and not to specific populations, sedimentary microbes begin to grow or increase their rate of growth following disturbance; this growth is often at the expense of their lipid stores. Values for phospholipid phosphate may be determined using the total-lipid extract or the phospholipid fraction. An analytical scheme yielding products of higher purity starts with the fractionation of the total lipid into neutral-lipid, glycolipid, and phospholipid fractions.
