Power curves for detecting regional temporal trends in total estrogenicity, atrazine, metolachlor, and sediment total polychlorinated biphenyl (PCB) concentrations in rivers in the Chesapeake Bay Watershed

Power curves for detecting regional temporal trends in total estrogenicity, atrazine, metolachlor, and sediment total polychlorinated biphenyl (PCB) concentrations in rivers in the Chesapeake Bay Watershed, USA. Power is a function of the annual percent decline (-5, -7, -10, -15, -20%/year) and the number of sites sampled each year (10, 20, 30, 50, 80, 100 sites). The horizontal dashed line at a power of 0.8 was added to aid interpretation. (from Wagner and others, 2021)