1366 MINERAL CYCLIZ™ :~: PPM INCHES 5 PPT 130004 1200043 100012 10000 9000: 8000} 70004 6 ° 00 50004 4000, 3000; 20004 1000, o4 _. (eA PPM| INCHES cr . a 40464 pS 2 331, A 304 : FOREST FLOOR SOIL 257 LEACHATES LEA teAc Ca-. Ca-45 —-— P-32 — — Rb-86 wmerme P83 woe oe RD. . . : i$; 10¢ eet? ¥ v r L T TUF ne MAY JUN JUL AUG SEPOCT NOVDEC JAN FEB MAR APR MAY JUNJUL AUG SEP CCT NOVOEC JAN FEE MAY JUN JUL AW Fie, 3. nonequilibrium of the newly applied tracers may have confoundedthe picture. This is indicated by the very high values of **P and ®*Rbcollected under the forest floor for only a few days after application during the spring of 1963 (see Table 2). generally increasing trend. The absence of. fall-flushing effect of the newly added “Ca ma indicate a slower movement through thefore: fivoor, This is more clearly indicated by ( release patterns of calcium newly added to t:: surface soil (see Fig. 3). Figures 4 and 5 present the data expressed 2 counts/min/ml leachate. Here, the diluix effects of incoming precipitation may be cb The release of **P from the forest floor, as served. For example, the “*Ca concentration ¢ the forest floor leachates sampled just before an * Parts per million x 10-* = per cent. soil during fall 1964, is decreasing (Fig. 5); + .the total amounts (Fig. 2) show a sharpincreas A similar trend may be observed for the releue presented in Fig. 2, shows a decreasing trend in contrast to Rb. - This might be explained by a after the first rains offall 1963, and of the suri 4 73 +2 | FOREST FLO LEACHATES rn floor show considerable fluctuations, but with torr PPT 4 —-— P-32 — — Rb-86 nd and after these rainstorms. However,a state of reduced microbiological activity due to the lower temperatures of the season. However,the effects of continued phosphorus fixation migt: be a significant factor. It is also known du: potassium is more mobile when thesoil systex becomessufficiently moist.) Therelease patterns of calcium from thefores 4. release might be explained by the total amount of forest floor and surface soil above the lysimeters. This effect is particularly noticeable in the release patterns of calcium applied during the fall of 1963, and rubidium applied during the fall of 1964 over the same lysimeter (see Fig. 2). The data as presented in Figs. 2 and 3 indicate a pronounced flushing effect immediately after the first fall rains, This is particularly so in a few of the calcium collections made just before o § $ § 8 8 3 2 gf? Fie, 2, Parts per million* of #P, °°Rb and *5Ca leached through the forest floor. sot. LEATHA MAY JUN JUL AUG Fro. 4. Concent: ‘eens pris