|Holtkamp, Michael - SWFWMD- SWIM, TAMPA, FL.|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: July 16, 2004
Publication Date: December 6, 2004
Citation: Sigua, G.C., Holtkamp, M.L., Coleman, S.W. 2004. Lake dredging and beyond: implication to agruculture and environment. NCER Abstract, p.392 Technical Abstract: Current dredged material disposal alternatives have several limitations. Options for dealing with dredged materials include leaving them alone, capping them with clean sediments, placing them in confined facilities, disposing of them at upland sites, treating them chemically, or using them for wetlands creation or other beneficial uses The ability to reuse lake-dredge materials (LDM) for agricultural purposes is important because it reduces the need for offshore disposal and provides an alternative to disposal of the materials in landfills. Often these materials can be obtained at little or no cost to the farmers or landowners. Thus, forage production offers an alternative to waste management since nutrients in the LDM are recycled into crops that are not directly consumed by humans. The objective of this study were to: (1) quantify the effect of applied LDM on soil physico-chemical properties (soil quality) at the disposal site; (2) assess LDM as a soil amendment to establish bahiagrass (BG) in a subtropical beef cattle pasture; and (3) determine the effect of LDM application on the crude protein (CP) and nutrient uptake of BG. Forage yield of BG during its establishment increased linearly (Forage Yield = 1724.3 + 25.6*LDM; R2 = 0.83; p < 0.0001) with increasing rates of LDM application. The CP of BG also varied significantly with varying levels of LDM applications. The tissues of BG with 100% LDM had the greatest CP content while the lowest CP content was from the control plots (LDM0). The CP of BG increased linearly with increasing rates of LDM application. The crude protein response to BG application can be described by a linear equation: Crude Protein = 10.4 + 0.05*LDM; R2 = 0.85; p < 0.0001. Land application of LDM may provide substantial benefits that will enhance the environment, community, and society. The heavy and trace metal contents of these materials were below the PEL and TEL. As such, the agricultural or livestock industry could utilize these LDM to produce forages. LDM should be regarded as a beneficial resource, as a part of the ecological system.