Discussion:
Q: Nitrogen and Seagrass. The seagrass Thalassia testudinum is an integral part of the Texas coastal ecosystem. Essential to the growth of T. testudinum is ammonium. Researchers Kun-Seop Lee and Kenneth H. Dunton of the Marine Science Institute of the University of Texas at Austin noticed that the seagrass beds in Corpus Christi Bay (CBB) were taller and thicker than those in Lower Laguna Madre (LLM). They compared the sediment ammonium concentrations in two locations and published their findings in Marine Ecology Progress Series (Vol. 196, pp.39-48). Following are the summary statistics on sediment ammonium concentrations, in micromoles, obtained by the researchers.
CCB LLM
X1=115.1 X2=24.3
S1=79.4 S2=10.5
N1=51 N2=19
At the 1% significance level, is there sufficient evidence to conclude that the mean sediment ammonium concentration in CCB exceeds that in LLM?