Salinization Lab

Salinization Lab Goals: To determine the relative germination sensitivity of various crop seeds to varying concentration of salt. To maintain the supplies by neat labeling and care so that they can be used by APES students year after year.

Salinization Lab Independent Variables: crop seeds, concentration of salt Dependent Variable: Percent germination, time to germinate Concentrations: Sea water 3.5% Freshwater .005% Dilutions of NaCl prepared by last year’s APES: 35g/L, 30g/L, 25g/L, 20g/L, 15g/L, 10g/L, 5g/L Tapwater .005% = .05g/L Distilled Water = 0g/L

Salinization Lab Guidelines Use every concentration available. Have 2 sets of samples to duplicate your experimental results for validation. Maximize the number of seeds within reason – amount available, reasonable to see & count. Transfer paper circles to each labeled petri dishes. Don’t swamp the seeds, they’ll drown. Use enough water to saturate the paper plus excess around the edges only. (2.0ml) Leave the petri dishes in sealed ziploc bags to minimize loss to evaporation. When observing, open the petri dishes to let air in and resoak the paper if necessary.

Salinization Data & Observations Conc Date 1 Date 2 Date 3 Date 4 Date 5

Salination Lab Report Title, Purpose, Hypothesis, Materials Variables: Manipulated, Responding, Controlled Procedures – Step by Step Data & Observations plus final percents Conclusions Compare results to your hypotheses Use data as evidence (at least 2 #s) Make recommendations to the farmers of San Joaquin valley with respect to the types of crops to plant relative to accumulated soil salination.