The Agricultural Value of Dredged Material.

An alternative for disposal of dredged sediments is to use them beneficially to amend marginal agricultural soils. To tudy the suitability of dredged material for crop production, 10 dreged material samples and 10 marginal soil samples were collected from locations in the United States. The soils were marginal for crop production and were of such character that additions of dredged material might improve their physical and chemical properties. The soils and dredged material samples were dried, ground, and mixed for plant growth studies and laboratory analysis. The following treatments were prepared: (a) soil alone; (b) 1/3 soil and 2/3 dredged material; (c) 2/3 soil and 1/3 dredged material; and (d) dredged material alone. In addition, three productive soils were chosen from the St. Paul, Minn., area to serve as controls in the plant growth studies. It is concluded that the dredged material used in this study would be beneficial for increasing agricultural production when mixed with marginal soils. Relationships between uptake and the availability of various soil elements were developed that can be used in setting the ratio of dredged material to marginal soil to be used in the field. Physical and chemical data, along with the plant growth data, were used to develop guidelines for the disposal of dredged material on marginal soils.
Report on Dredged Material Research Program.