Subplotting

Tustin s rule. Subplot (211) and (212) creates a 2 row, single column plot matrix (i.e. produces 2 plots, one beneath the other). 

Reactions take up the rest of the course, and they are typically broken down into chapters based on categories. Within each of these chapters, there is acmaUy a subplot that fits into the grand story. 

To avoid cross-contamination of control samples, untreated controls are collected before the treated samples. Preferably, personnel who handle the upper cores should be different from those handling the lower depth cores. This further reduces potential cross-contamination of lower depth cores. Sampler handlers should change their gloves each time a new subplot is sampled. The use of disposable shoe covers also lessens the possibility of cross-contamination. 

All application verification and soil samples must be individually labeled with unique sample identification (ID) and other identifying information such as study ID, test substance name, sample depth, replicate, subplot and date of collection, as appropriate. Proper study documentation requires that sample lists and labels be created prior to work commencing in the field. Water- and tear-resistant labels should be used since standard paper labels may become water-soaked and easily torn during sample handling. Sample lists should have the same information on them as the labels and are a convenient place to record plot randomization, initials of the individual who collected the sample, and date of collection. As such, the sample list is important in establishing chain of custody from the point of sample collection until its arrival at the laboratory. 

The regulations require three samples from the treated plot (one from each subplot) and a single sample from the control plot at each sampling interval. For foliage the preferred technique is to collect leaf punch samples. Leaf punch samplers are available in 5-, 2.5- and 1.25-cm punch areas. Common practice requires a sample of 40-5-cm leaf disks to provide a 400-cm sample using both the top and bottom of the leaf disk to calculate sample surface area. 

In the oxamyl tomato study, the DFR samples were obtained using a 5-cm Birkestrand sampler (10-cm disk size using the upper and lower surfaces). The sample consisted of 40 leaf disks or 400 cm from each subplot. The samples were collected impartially or in a nondirected approach from the middle two rows. The plot was four rows wide and the tractor came into contact with the first and fourth rows as the application was made. The middle two rows should be undisturbed by this movement and should therefore provide a more representative sample. 

As an option, we can omit the subplot command and put the magnitude and phase plots in individual figures. 

After using the subplot () command and before doing any other plots, we should have a habit to reset the window with... 

Figure 5. Results of an empirical model that calculated, for each low-pressure impactor size range, the percentage recoil losses of Pb-214 [subplot (a)] necessary to produce a calculated Pb-214 distribution is best agreement with the observed distribution [subplot (b)]. Lower Dp limits are arbitrary.

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