Oak and poplar leaves were leached with distilled water in laboratory columns to simulate the release of soluble phosphorus (P) forms to urban runoff. Most of the soluble phosphorus leached was reactive in a molybdenum blue analysis. The leaves tested yielded P/g of leaves. Consecutive leachings of an oak leaf sample yielded soluble P in amounts related to the effective soaking period between leachings and to the number of preceding leachings. Cut up leaves released almost three times as much soluble P as intact leaves. Leaves collected from the littoral zone of Lake Mendota leached less P than control leaves collected on the shore nearby. The moisture retained on leaves after a rainstorm contained significant soluble reactive P. The results of this investigation point to the importance of proper leaf pickup and control in order to minimize the phosphorus content of urban drainage during the fall of the year.Recent studies by Kluesener (1971) on the nutrient sources

Three of the major diamines, 2,4-toluenediamine (2,4-TDA), 2,6-toluenediamine (2,6-TDA), and 4,4′-methylenedianiline (4,4′-MDA), used as intermediates in the production of polyurethanes have been studied for their fate in soil. Previous literature has reported variable biodegradation of these industrially important compounds with no information on their expected fate in soil. Their sorption to two soils and biodegradation in soil under both aerobic and anaerobic conditions have been studied. Under aerobic and anaerobic conditions, sorption constants, K oc , for both isomers of TDA on loam soils were 500-1300 after 8 h of contact, and the corresponding K oc values for MDA were 3800-5700 after 8 h of contact. Both isomers of TDA and 4,4′-MDA appear to be sorbed only a little more strongly under aerobic than anaerobic conditions. The 14 carbon-labeled TDA isomers and MDA started to biodegrade immediately after mixing with aerobic soil with the recovery of 2-3% 14 CO 2 after only 3 days. The biodegradation slowed later with recovery of 11-14% 14 CO 2 after 28 days and an apparent 34-40% biodegradation after 1 year, based on loss of 14 C. Under anaerobic methanogenic conditions, no 14 CH 4 or 14 CO 2 was recovered from any of the diamines after 71 days of incubation.

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