The Experts below are selected from a list of 2208 Experts worldwide ranked by ideXlab platform
Timothy D Stark - One of the best experts on this subject based on the ideXlab platform.
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discussion of settlement of Dredged and contaminated material placement areas ii primary consolidation secondary compression and desiccation of Dredged fill input parameters by timothy d stark hangseok choi and paul r schroeder
Journal of Waterway Port Coastal and Ocean Engineering-asce, 2006Co-Authors: Timothy D Stark, Hangseok Choi, Paul R SchroederAbstract:The ERDC interim correlation for the initial void ratio corresponding to zero effective stress e00 of Dredged Materials with PI, the 14 data points on which it is based, and 10 additional data points for Australian Dredged Materials are shown in Fig. 1. The ERDC and Australian data points were all obtained from best curve fits to void ratio-effective stress data from self-weight consolidation tests conducted in accordance with Cargill 1986 and are thus directly comparable. The initial liquidity indices of the Australian sediments and the 12 ERDC sediments for which data are available ranged from 3.7 to 7.3 and from 4.2 to 33.3, respectively. Hence, although the e00 of the Australian Materials are relatively low Fig. 1 , this is not attributable to low initial mois-
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discussion of settlement of Dredged and contaminated material placement areas ii primary consolidation secondary compression and desiccation of Dredged
2006Co-Authors: Fill Input Parameters, Timothy D Stark, Hangseok Choi, Paul R Schroeder, P H MorrisAbstract:The computer program, PSDDF, which requires minimal resources to implement, is a valuable tool for the analysis of the consolidation and desiccation of Dredged Materials. However, four of the suggested input data correlations require further consideration. Initial Void Ratio Correlation The ERDC interim correlation for the initial void ratio corresponding to zero effective stress e00 of Dredged Materials with PI, the 14 data points on which it is based, and 10 additional data points for Australian Dredged Materials are shown in Fig. 1. The ERDC and Australian data points were all obtained from best curve fits to void ratio-effective stress data from self-weight consolidation tests conducted in accordance with Cargill 1986 and are thus directly comparable. The initial liquidity indices of the Australian sediments and the 12 ERDC sediments for which data are available ranged from 3.7 to 7.3 and from 4.2 to 33.3, respectively. Hence, although the e00 of the Australian Materials are relatively low Fig. 1, this is not attributable to low initial moisture contents. The ERDC correlation is statistically strong, with a level of significance of 3.1%. However, the eight Australian CH data points clearly show that it is not generally applicable and should be used with caution.
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settlement of Dredged and contaminated material placement areas ii primary consolidation secondary compression and desiccation of Dredged fill input parameters
Journal of Waterway Port Coastal and Ocean Engineering-asce, 2005Co-Authors: Timothy D Stark, Hangseok Choi, Paul R SchroederAbstract:This paper presents practical applications of PSDDF (Primary Consolidation, Secondary Compression, and Desiccation of Dredged Fill), which is described in a companion paper by the writers. In addition, consolidation and desiccation parameters for 27 Dredged Materials are presented from 20 U.S. Army Corps of Engineers placement areas to facilitate usage of PSDDF. The consolidation parameters of three cohesionless soils for sand capping and drainage and three compressible foundation Materials are included to provide a PSDDF user with suitable parameters for these material types. To reduce the difficulty of obtaining the consolidation and desiccation parameters for Dredged material, empirical correlations between the required parameters and soil index properties are presented.
S W Coleman - One of the best experts on this subject based on the ideXlab platform.
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land application of carbonatic lake Dredged Materials effects on soil quality and forage productivity
Journal of Environmental Quality, 2006Co-Authors: Gilbert C Sigua, S W Coleman, Mike L HoltkampAbstract:The ability to reuse carbonatic lake-Dredged Materials (CLDM) for agricultural purposes is important because it reduces offshore disposal and provides an alternative to disposal of the Materials in landfills that are already overtaxed. A four-year (2001 to 2005) study on land application of CLDM as an option for disposal was conducted on a beef cattle pasture in south central Florida. The objectives of this study were (i) to assess CLDM as a soil amendment to improve quality of sandy soils in most subtropical beef cattle pastures and (ii) to determine the effect of CLDM on productivity and nutritive values of
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assessing the efficacy of Dredged Materials from lake panasoffkee florida implication to environment and agriculture part 1 soil and environmental quality aspect
Environmental Science and Pollution Research, 2004Co-Authors: Gilbert C Sigua, Mike L Holtkamp, S W ColemanAbstract:Dredged Materials because of its variable but unique physical and chemical properties are often viewed by society and regulators as pollutants, but many have used these Materials in coastal nourishment, land or wetland creation, construction Materials, and for soil improvement as a soil amendment. Environmental impact assessment is an important pre-requisite to many dredging initiatives. 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. Additional research on disposal options of Dredged Materials are much needed to supply information on criteria testing and evaluation of the physical and chemical impacts of Dredged Materials at a disposal site, as well as information on many other aspects of dredging and Dredged material disposal. While preliminary efforts are underway to provide information to establish criteria for land disposal, testing procedures for possible land disposal of contaminated sediments are still in their developing stage. The objective of this study (Part 1) was to quantify the effect of applied LDM from Lake Panasoffkee (LP), Florida on soil physico-chemical properties (soil quality) at the disposal site. This series of two papers aims at providing assessment of the efficacy of lake-Dredged Materials from LP especially its implication to environment (soil quality, Pan 1) and agriculture (forage quality and pasture establishment, Part 2). The experimental treatments that were evaluated consisted of different ratios of natural soil (NS) to LDM: LDMO (100% NS:0% LDM); LDM25 (75% NS:25% LDM); LDM50 (50% NS:50% LDM); LDM75 (25% NS:75% LDM); and LDM100 (0% NS:100% LDM). Field layout was based on the principle of a completely randomized block design with four replications. The Mehlich 1 method (0.05N HCl in 0.025N H2SO4) was used for chemical extraction of soil. Soil P and other exchangeable cations (Ca, Mg, K, Al, and Fe) were analyzed using an Inductively Coupled Plasma (ICP) Spectroscopy. The effects of Dredged Materials addition on soil quality and compaction were analyzed statistically following the PROC ANOVA procedures. Sediments that were Dredged from LP have high CaCO3 content (82%) and when these Materials were incorporated into existing topsoil they would have the same favorable effects as liming the field. Thus, sediments with high CaCO3 may improve the physical and chemical conditions of subtropical sandy pastures. The heavy and trace metal contents of LDM were below the probable effect levels (PEL) and threshold effect levels (TEL). Average values for Pb, Zn, As, Cu, Hg, Se, Cd, and Ni of 5.2 ± 1.3, 7.0 ± 0.6,4.4 ± 0.1, 8.7 s= 1.2, 0.01 ± 0.02,0.02 ± 0.02,2.5 s 0.1, and 14.6 = 6.4 mg kg-1, respectively, were below the TEL and the PEL. TEL represents the concentrations of sediment-associated contaminants that are considered to cause significant hazards to aquatic organisms, while, PEL represents the lower limit of the range of the contaminant concentrations that are usually or always associated with adverse biological effects. As such, the agricultural or livestock industry could utilize these LDM to produce forages. LDM should be regarded as a beneficiai resource, as a part of the ecological system. Addition of LDM had significant (p ≤ 0.001) effects on soil physico-chemical properties and soil quality. Compared with the control plots, the soils in plots amended with LDM exhibited: (1) lower degree of soil compaction; (2) an increase in soil pH, Ca, and Mg; (3) decrease in the levels of soil Mn, Cu, Fe, Zn, and Si; and (4) no significant change in the level of Na in the soil. Results have shown the favorable influence that LDM had on soil compaction. The treatment x year interaction effect was not significant, but the average soil compaction varied widely (p ≤ 0.001) with LDM application. In 2002 and 2003, soil compaction of plots was lowered significantly as a result of LDM additions. The least compacted soils in 2002 and 2003 were observed from plots with LDM75 with mean soil compaction of 300 × 103 and 350 × 103 Pa, respectively. Beneficial uses of Dredged Materials from LP, Florida are both economical and environmental. Often these Materials can be obtained at little or no cost to the farmers or landowners in south Florida. Environmentally, dredging of sediments that are rich in CaCO3 should restore the 19.4-sq km LP by removing natural sediments from the lake bottom to improve the fishery, water quality, and navigation of the lake. The bottom sediment Materials from lakes, river, and navigational channels usually are composed of upland soil enriched with nutrients and organic matter. These Materials should be regarded as a beneficial resource to be used productively and not to be discarded as spoil Materials. Land application of LDM from LP may not only provide substantial benefits that will enhance the environment, community, and society in south Florida, but also in other parts of the world especially those areas having tropical and subtropical climate with forage-based beef cattle pastures. The heavy and trace metal contents of LDM from LP were below the PEL and TEL. As such, the agricultural or livestock industry could utilize these LDM to produce forages (Part 2 of this study). LDM should be regarded as a beneficial resource, as a part of the ecological system. Further studies are still needed to determine whether the environmental and ecological implications of LDM application are satisfied over the longer term.
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assessing the efficacy of Dredged Materials from lake panasoffkee florida implication to environment and agriculture part 2 pasture establishment and forage productivity
Environmental Science and Pollution Research, 2004Co-Authors: Gilbert C Sigua, Mike L Holtkamp, S W ColemanAbstract: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 (Part 2) were to: (1) assess dredge Materials from Lake Panasoffkee, Florida as a soil amendment to establish bahiagrass (BG) in a subtropical beef cattle pasture in Sumter County, Florida; and (2) determine the effect of LDM application on the crude protein (CP) and nutrient uptake of BG. This series of two papers aims at providing assessment of the efficacy of lake-Dredged Materials especially its implication to environment (soil quality, Part 1) and agriculture (forage quality and pasture establishment. Part 2). The experimental treatments that were evaluated consisted of different ratios of natural soil (NS) to LDM: LDMO (100% NS:0% LDM); LDM25 (75% NS:25% LDM); LDM50 (50% NS:50% LDM); LDM75 (25% NS:75% LDM); and LDM100 (0% NS:100% LDM). Bahiagrass plots at its early establishment were cut to a 5-cm stubble height on Julian days 112 and harvested to the same stubble height on Julian days 238 and on Julian days 546 following the double-ring method. Field layout was based on the principle of a completely randomized block design with four replications. Plant samples harvested at 546 Julian days were ground to pass through a 1-mm mesh screen in a Wiley mill. Ground forage was analyzed for crude protein. Ground forage samples were also analyzed for tissue P, K, Ca, Mg, Mn, Cu, Fe, Al, and Mo concentrations using an ICP spectroscopy. The effects of Dredged Materials addition on forage yield and on crude protein and nutrient uptake that were taken at 546 Julian days were analyzed statistically following the PROC ANOVA procedures. Part 1 of this study demonstrated that the heavy and trace metal contents of LDM were below the probable effect levels and threshold effect levels. As such, the agricultural or livestock industry could utilize these LDM to produce forages. Results showed consistently and significantly (p ≤ 0.001) higher BG biomass production and CP from plots amended with LDM than those of BG planted on plots with 0% LDM. Forage yield of BG during its establishment increased linearly (Forage Yield = 1724.3 + 25.64*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 (LDMO). 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 = 10.38 + 0.052*LDM; R2 = 0.85 p ≤ 0.0001. Addition of LDM had increased the levels of Ca by about 1811 % when compared with the level of soil Ca among plots with no LDM application. Liming the field could have some direct and indirect effects on the chemical status of the soils. The physiological functions performed by Ca in plants are not clearly defined, but it has been suggested that Ca favors the formation of and increases the protein content of mitochondria. Beneficial uses of Dredged Materials from LP, Florida are both economical and environmental. Often these Materials can be obtained at little or no cost to the farmers or landowners. Results showed that Dredged Materials can be used as soil amendments (lime and fertilizer) for early establishment of BG in beef cattle pastures. Environmentally, dredging of sediments that are rich in CaCO3 should restore the 19.4-sq km LP by removing natural sediments from the lake bottom to improve the fishery, water quality, and navigation of the lake. The nutritional uptake of BG grown in unfertile sandy soils of Sumter County was enhanced significantly (p≤0.001) by LDM addition. Uptake of TKN, TP, K, Ca, and Mg were remarkably increased as a result of LDM. Land application of LDM from LP may not only provide substantial benefits that will enhance the environment, community, and society in south Florida, but also in other parts of the world especially those areas with forage-based beef cattle pastures and similar climatic conditions. The heavy and trace metal contents of these Materials were below the PEL and TEL (see Part 1). 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. Although our results have demonstrated the favorable and beneficial effects of added LDM on the early establishment of BG in pasture fields., further studies are still needed not only in pastures of south Florida, but also in other areas with subtropical or tropical climatic conditions to determine whether the environmental and ecological implications of LDM application are satisfied over the longer term.
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land application of lake Dredged Materials for bahiagrass establishment in the subtropical beef pasture
Journal of Soils and Sediments, 2003Co-Authors: Gilbert C Sigua, Mike L Holtkamp, John M Linton, S W ColemanAbstract:The continued need to dredge lakes, rivers, and canals in Florida, both for maintenance and environmental improvement, will produce millions of cubic meters of Dredged Materials. Productive disposal options of lake-Dredged Materials (LDM) may provide substantial and intangible benefits that will enhance the environment, community, and society. The objective of this study was to assess lake-Dredged Materials from Lake Panasoffkee as soil amendment for early establishment of bahiagrass (BG,Paspalum notatum Flugge) in subtropical beef cattle pasture at Sumter County, Florida. Results and Discussion. This study encompassed two phases: Phase 1 comprised of five small observation plots (0.3 x 0.3 m); Phase 2 consisted of five larger test plots (30.5 x 30.5 m). Each of the plots in Phase 1 and Phase 2 had a different ratio LDM to natural soil (NS): Plot 1 (0% LDM + 100% NS); Plot 2 (25% LDM + 75% NS); Plot 3 (50% LDM + 50% NS); Plot 4 (75% LDM + 25% NS); and Plot 5 (100% LDM + 0% NS). Each plot was seeded with BG and early growth and yield establishment were monitored for 16 weeks. Results disclosed significantly taller (p ≤ 0.001) plants and higher biomass production (p ≤ 0.001) of BG from plots amended with 75% LDM than those of BG planted on plots with 0% LDM. Results suggest that LDM can serve as source of lime and fertilizer to establish BG beef pasture fields. Sediments with high CaCO3 improved the physical and chemical conditions of subtropical beef pastures. Lake-Dredged Materials could be removed from the spoil containment areas, trucked to other locations, and incorporated into existing fields for agricultural uses. There is still much to be learned, but it is certain that Lake Panasoffkee sediments should be regarded as a resource, with no observed harmful ecological effects. 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. This study has been continued for several years to explore and assess the long term efficacy of LDM on productivity and quality of BG beyond its early establishment stage.
Gilbert C Sigua - One of the best experts on this subject based on the ideXlab platform.
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recycling biosolids and lake Dredged Materials to pasture based animal agriculture alternative nutrient sources for forage productivity and sustainability a review
Agronomy for Sustainable Development, 2009Co-Authors: Gilbert C SiguaAbstract:Domestic sewage sludge or biosolids and lake-Dredged Materials are examples of Materials that can be used to cut fertilizer costs in pasture-based animal agriculture. Sustainable biosolids and lake-Dredged Materials management is based upon controlling and influencing the quantity, quality and characteristics of these Materials in such a way that negative impacts to the environment are avoided and beneficial uses are optimized. This article examines the following two key questions. Is the use of these Materials in an agricultural setting harmless and sensible? Is the use of biosolids secure in all climates, in all soils and is it sustainable over the long term? Recycling biosolids and lake-Dredged Materials to pasture-based animal production is quite productive as alternative nutrient sources for forage production. Perennial grass can be a good choice for repeated applications of biosolids and lake-Dredged Materials. Although biosolids and lake-Dredged Materials supply some essential plant nutrients and provide soil property-enhancing organic matter, land-application programs still generate some concerns because of possible health and environmental risks involved. Repeated applications of biosolids and lake-Dredged Materials indicate no harmful effects on soil quality and forage quality. Beneficial uses of biosolids and lake-Dredged Materials are both economical and environmental. The concentrations of soil nitrogen and phosphorus following repeated application of biosolids were far below the contamination risk in the environment. The residual effect of biosolids over the long term can be especially significant in many forage-based pastures where only 50% of the million hectares of pastures are given inorganic nitrogen yearly. Long-term studies have demonstrated the favorable and beneficial effects of added lake-Dredged Materials on the early establishment of bahiagrass in sandy pasture fields. Often these Materials can be obtained at little or no cost to the farmers or landowners. Lake-Dredged Materials can be used as soil amendments (lime and fertilizer) for early establishment of bahiagrass in beef cattle pastures. Bahiagrass in plots that were treated with biosolids and lake-dredge Materials had significantly higher forage yield and crude protein content when compared with those bahiagrass in the control plots or untreated plants.
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land application of carbonatic lake Dredged Materials effects on soil quality and forage productivity
Journal of Environmental Quality, 2006Co-Authors: Gilbert C Sigua, S W Coleman, Mike L HoltkampAbstract:The ability to reuse carbonatic lake-Dredged Materials (CLDM) for agricultural purposes is important because it reduces offshore disposal and provides an alternative to disposal of the Materials in landfills that are already overtaxed. A four-year (2001 to 2005) study on land application of CLDM as an option for disposal was conducted on a beef cattle pasture in south central Florida. The objectives of this study were (i) to assess CLDM as a soil amendment to improve quality of sandy soils in most subtropical beef cattle pastures and (ii) to determine the effect of CLDM on productivity and nutritive values of
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assessing the efficacy of Dredged Materials from lake panasoffkee florida implication to environment and agriculture part 1 soil and environmental quality aspect
Environmental Science and Pollution Research, 2004Co-Authors: Gilbert C Sigua, Mike L Holtkamp, S W ColemanAbstract:Dredged Materials because of its variable but unique physical and chemical properties are often viewed by society and regulators as pollutants, but many have used these Materials in coastal nourishment, land or wetland creation, construction Materials, and for soil improvement as a soil amendment. Environmental impact assessment is an important pre-requisite to many dredging initiatives. 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. Additional research on disposal options of Dredged Materials are much needed to supply information on criteria testing and evaluation of the physical and chemical impacts of Dredged Materials at a disposal site, as well as information on many other aspects of dredging and Dredged material disposal. While preliminary efforts are underway to provide information to establish criteria for land disposal, testing procedures for possible land disposal of contaminated sediments are still in their developing stage. The objective of this study (Part 1) was to quantify the effect of applied LDM from Lake Panasoffkee (LP), Florida on soil physico-chemical properties (soil quality) at the disposal site. This series of two papers aims at providing assessment of the efficacy of lake-Dredged Materials from LP especially its implication to environment (soil quality, Pan 1) and agriculture (forage quality and pasture establishment, Part 2). The experimental treatments that were evaluated consisted of different ratios of natural soil (NS) to LDM: LDMO (100% NS:0% LDM); LDM25 (75% NS:25% LDM); LDM50 (50% NS:50% LDM); LDM75 (25% NS:75% LDM); and LDM100 (0% NS:100% LDM). Field layout was based on the principle of a completely randomized block design with four replications. The Mehlich 1 method (0.05N HCl in 0.025N H2SO4) was used for chemical extraction of soil. Soil P and other exchangeable cations (Ca, Mg, K, Al, and Fe) were analyzed using an Inductively Coupled Plasma (ICP) Spectroscopy. The effects of Dredged Materials addition on soil quality and compaction were analyzed statistically following the PROC ANOVA procedures. Sediments that were Dredged from LP have high CaCO3 content (82%) and when these Materials were incorporated into existing topsoil they would have the same favorable effects as liming the field. Thus, sediments with high CaCO3 may improve the physical and chemical conditions of subtropical sandy pastures. The heavy and trace metal contents of LDM were below the probable effect levels (PEL) and threshold effect levels (TEL). Average values for Pb, Zn, As, Cu, Hg, Se, Cd, and Ni of 5.2 ± 1.3, 7.0 ± 0.6,4.4 ± 0.1, 8.7 s= 1.2, 0.01 ± 0.02,0.02 ± 0.02,2.5 s 0.1, and 14.6 = 6.4 mg kg-1, respectively, were below the TEL and the PEL. TEL represents the concentrations of sediment-associated contaminants that are considered to cause significant hazards to aquatic organisms, while, PEL represents the lower limit of the range of the contaminant concentrations that are usually or always associated with adverse biological effects. As such, the agricultural or livestock industry could utilize these LDM to produce forages. LDM should be regarded as a beneficiai resource, as a part of the ecological system. Addition of LDM had significant (p ≤ 0.001) effects on soil physico-chemical properties and soil quality. Compared with the control plots, the soils in plots amended with LDM exhibited: (1) lower degree of soil compaction; (2) an increase in soil pH, Ca, and Mg; (3) decrease in the levels of soil Mn, Cu, Fe, Zn, and Si; and (4) no significant change in the level of Na in the soil. Results have shown the favorable influence that LDM had on soil compaction. The treatment x year interaction effect was not significant, but the average soil compaction varied widely (p ≤ 0.001) with LDM application. In 2002 and 2003, soil compaction of plots was lowered significantly as a result of LDM additions. The least compacted soils in 2002 and 2003 were observed from plots with LDM75 with mean soil compaction of 300 × 103 and 350 × 103 Pa, respectively. Beneficial uses of Dredged Materials from LP, Florida are both economical and environmental. Often these Materials can be obtained at little or no cost to the farmers or landowners in south Florida. Environmentally, dredging of sediments that are rich in CaCO3 should restore the 19.4-sq km LP by removing natural sediments from the lake bottom to improve the fishery, water quality, and navigation of the lake. The bottom sediment Materials from lakes, river, and navigational channels usually are composed of upland soil enriched with nutrients and organic matter. These Materials should be regarded as a beneficial resource to be used productively and not to be discarded as spoil Materials. Land application of LDM from LP may not only provide substantial benefits that will enhance the environment, community, and society in south Florida, but also in other parts of the world especially those areas having tropical and subtropical climate with forage-based beef cattle pastures. The heavy and trace metal contents of LDM from LP were below the PEL and TEL. As such, the agricultural or livestock industry could utilize these LDM to produce forages (Part 2 of this study). LDM should be regarded as a beneficial resource, as a part of the ecological system. Further studies are still needed to determine whether the environmental and ecological implications of LDM application are satisfied over the longer term.
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assessing the efficacy of Dredged Materials from lake panasoffkee florida implication to environment and agriculture part 2 pasture establishment and forage productivity
Environmental Science and Pollution Research, 2004Co-Authors: Gilbert C Sigua, Mike L Holtkamp, S W ColemanAbstract: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 (Part 2) were to: (1) assess dredge Materials from Lake Panasoffkee, Florida as a soil amendment to establish bahiagrass (BG) in a subtropical beef cattle pasture in Sumter County, Florida; and (2) determine the effect of LDM application on the crude protein (CP) and nutrient uptake of BG. This series of two papers aims at providing assessment of the efficacy of lake-Dredged Materials especially its implication to environment (soil quality, Part 1) and agriculture (forage quality and pasture establishment. Part 2). The experimental treatments that were evaluated consisted of different ratios of natural soil (NS) to LDM: LDMO (100% NS:0% LDM); LDM25 (75% NS:25% LDM); LDM50 (50% NS:50% LDM); LDM75 (25% NS:75% LDM); and LDM100 (0% NS:100% LDM). Bahiagrass plots at its early establishment were cut to a 5-cm stubble height on Julian days 112 and harvested to the same stubble height on Julian days 238 and on Julian days 546 following the double-ring method. Field layout was based on the principle of a completely randomized block design with four replications. Plant samples harvested at 546 Julian days were ground to pass through a 1-mm mesh screen in a Wiley mill. Ground forage was analyzed for crude protein. Ground forage samples were also analyzed for tissue P, K, Ca, Mg, Mn, Cu, Fe, Al, and Mo concentrations using an ICP spectroscopy. The effects of Dredged Materials addition on forage yield and on crude protein and nutrient uptake that were taken at 546 Julian days were analyzed statistically following the PROC ANOVA procedures. Part 1 of this study demonstrated that the heavy and trace metal contents of LDM were below the probable effect levels and threshold effect levels. As such, the agricultural or livestock industry could utilize these LDM to produce forages. Results showed consistently and significantly (p ≤ 0.001) higher BG biomass production and CP from plots amended with LDM than those of BG planted on plots with 0% LDM. Forage yield of BG during its establishment increased linearly (Forage Yield = 1724.3 + 25.64*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 (LDMO). 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 = 10.38 + 0.052*LDM; R2 = 0.85 p ≤ 0.0001. Addition of LDM had increased the levels of Ca by about 1811 % when compared with the level of soil Ca among plots with no LDM application. Liming the field could have some direct and indirect effects on the chemical status of the soils. The physiological functions performed by Ca in plants are not clearly defined, but it has been suggested that Ca favors the formation of and increases the protein content of mitochondria. Beneficial uses of Dredged Materials from LP, Florida are both economical and environmental. Often these Materials can be obtained at little or no cost to the farmers or landowners. Results showed that Dredged Materials can be used as soil amendments (lime and fertilizer) for early establishment of BG in beef cattle pastures. Environmentally, dredging of sediments that are rich in CaCO3 should restore the 19.4-sq km LP by removing natural sediments from the lake bottom to improve the fishery, water quality, and navigation of the lake. The nutritional uptake of BG grown in unfertile sandy soils of Sumter County was enhanced significantly (p≤0.001) by LDM addition. Uptake of TKN, TP, K, Ca, and Mg were remarkably increased as a result of LDM. Land application of LDM from LP may not only provide substantial benefits that will enhance the environment, community, and society in south Florida, but also in other parts of the world especially those areas with forage-based beef cattle pastures and similar climatic conditions. The heavy and trace metal contents of these Materials were below the PEL and TEL (see Part 1). 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. Although our results have demonstrated the favorable and beneficial effects of added LDM on the early establishment of BG in pasture fields., further studies are still needed not only in pastures of south Florida, but also in other areas with subtropical or tropical climatic conditions to determine whether the environmental and ecological implications of LDM application are satisfied over the longer term.
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land application of lake Dredged Materials for bahiagrass establishment in the subtropical beef pasture
Journal of Soils and Sediments, 2003Co-Authors: Gilbert C Sigua, Mike L Holtkamp, John M Linton, S W ColemanAbstract:The continued need to dredge lakes, rivers, and canals in Florida, both for maintenance and environmental improvement, will produce millions of cubic meters of Dredged Materials. Productive disposal options of lake-Dredged Materials (LDM) may provide substantial and intangible benefits that will enhance the environment, community, and society. The objective of this study was to assess lake-Dredged Materials from Lake Panasoffkee as soil amendment for early establishment of bahiagrass (BG,Paspalum notatum Flugge) in subtropical beef cattle pasture at Sumter County, Florida. Results and Discussion. This study encompassed two phases: Phase 1 comprised of five small observation plots (0.3 x 0.3 m); Phase 2 consisted of five larger test plots (30.5 x 30.5 m). Each of the plots in Phase 1 and Phase 2 had a different ratio LDM to natural soil (NS): Plot 1 (0% LDM + 100% NS); Plot 2 (25% LDM + 75% NS); Plot 3 (50% LDM + 50% NS); Plot 4 (75% LDM + 25% NS); and Plot 5 (100% LDM + 0% NS). Each plot was seeded with BG and early growth and yield establishment were monitored for 16 weeks. Results disclosed significantly taller (p ≤ 0.001) plants and higher biomass production (p ≤ 0.001) of BG from plots amended with 75% LDM than those of BG planted on plots with 0% LDM. Results suggest that LDM can serve as source of lime and fertilizer to establish BG beef pasture fields. Sediments with high CaCO3 improved the physical and chemical conditions of subtropical beef pastures. Lake-Dredged Materials could be removed from the spoil containment areas, trucked to other locations, and incorporated into existing fields for agricultural uses. There is still much to be learned, but it is certain that Lake Panasoffkee sediments should be regarded as a resource, with no observed harmful ecological effects. 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. This study has been continued for several years to explore and assess the long term efficacy of LDM on productivity and quality of BG beyond its early establishment stage.
T. Ángel Delvalls - One of the best experts on this subject based on the ideXlab platform.
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a multivariate assessment of sediment contamination in Dredged Materials from spanish ports
Journal of Hazardous Materials, 2009Co-Authors: M C Casadomartinez, Jesus M Forja, T. Ángel DelvallsAbstract:This paper summarises the performance of simple multivariate exploratory analyses to investigate on their potential application for Dredged material characterization and management. The data from 25 sampling stations located at 7 different Spanish ports, produced a matrix consisting of 300 observations on 10 variables: the metals Cd, Cu, Cr, Hg, Ni, Pb and Zn, the metalloid As, the sum of PAHs and PCB congeners, and the proportion of fines and organic matter content. The cluster analysis was suitable to separate the sediments according to the extent of contamination while the PCA indicated that the data was defined by two principal factors: a first one that accounts for 56.4% of the total variance, describing the metallic contaminants except Ni and Cr, and a second one that accounts for 14.4% of the total variance describing the organic contaminants PAHs and PCBs. The use of these two simple and untutored multivariate techniques seems a cost-effective approach for future pre-dredging investigations in the studied areas providing useful information for Dredged material characterization and management with little additional effort.
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using sediment quality guidelines for Dredged material management in commercial ports from spain
Environment International, 2006Co-Authors: M C Casadomartinez, J L Buceta, M J Belzunce, T. Ángel DelvallsAbstract:Dredged material contamination was assessed in different commercial ports from Spain: Port of Cadiz and Huelva, South West; Bilbao and Pasajes, North; Cartagena and Barcelona, East; Coruna, North West. Sediment from different locations of these ports was sampled and was characterized following the Spanish recommendations for Dredged material management. This characterization included grain size distribution, organic matter content and concentration of the chemical compounds included in the list of pollutants and hazardous substances (As, Cd, Cu, Cr, Hg, Ni, Pb and Zn; PCB congeners IUPAC number 28, 52, 101, 118, 138, 153 and 180; PAHs were also analyzed). The results were compared to the limit values of Spanish Action Levels that define the different categories for assessment and management. A set of empirically derived sediment quality guidelines (SQG) was used to assess the possible toxicity of the Dredged Materials and to improve the use of the chemical approach to characterize Dredged material for its management.
Mike L Holtkamp - One of the best experts on this subject based on the ideXlab platform.
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land application of carbonatic lake Dredged Materials effects on soil quality and forage productivity
Journal of Environmental Quality, 2006Co-Authors: Gilbert C Sigua, S W Coleman, Mike L HoltkampAbstract:The ability to reuse carbonatic lake-Dredged Materials (CLDM) for agricultural purposes is important because it reduces offshore disposal and provides an alternative to disposal of the Materials in landfills that are already overtaxed. A four-year (2001 to 2005) study on land application of CLDM as an option for disposal was conducted on a beef cattle pasture in south central Florida. The objectives of this study were (i) to assess CLDM as a soil amendment to improve quality of sandy soils in most subtropical beef cattle pastures and (ii) to determine the effect of CLDM on productivity and nutritive values of
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assessing the efficacy of Dredged Materials from lake panasoffkee florida implication to environment and agriculture part 1 soil and environmental quality aspect
Environmental Science and Pollution Research, 2004Co-Authors: Gilbert C Sigua, Mike L Holtkamp, S W ColemanAbstract:Dredged Materials because of its variable but unique physical and chemical properties are often viewed by society and regulators as pollutants, but many have used these Materials in coastal nourishment, land or wetland creation, construction Materials, and for soil improvement as a soil amendment. Environmental impact assessment is an important pre-requisite to many dredging initiatives. 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. Additional research on disposal options of Dredged Materials are much needed to supply information on criteria testing and evaluation of the physical and chemical impacts of Dredged Materials at a disposal site, as well as information on many other aspects of dredging and Dredged material disposal. While preliminary efforts are underway to provide information to establish criteria for land disposal, testing procedures for possible land disposal of contaminated sediments are still in their developing stage. The objective of this study (Part 1) was to quantify the effect of applied LDM from Lake Panasoffkee (LP), Florida on soil physico-chemical properties (soil quality) at the disposal site. This series of two papers aims at providing assessment of the efficacy of lake-Dredged Materials from LP especially its implication to environment (soil quality, Pan 1) and agriculture (forage quality and pasture establishment, Part 2). The experimental treatments that were evaluated consisted of different ratios of natural soil (NS) to LDM: LDMO (100% NS:0% LDM); LDM25 (75% NS:25% LDM); LDM50 (50% NS:50% LDM); LDM75 (25% NS:75% LDM); and LDM100 (0% NS:100% LDM). Field layout was based on the principle of a completely randomized block design with four replications. The Mehlich 1 method (0.05N HCl in 0.025N H2SO4) was used for chemical extraction of soil. Soil P and other exchangeable cations (Ca, Mg, K, Al, and Fe) were analyzed using an Inductively Coupled Plasma (ICP) Spectroscopy. The effects of Dredged Materials addition on soil quality and compaction were analyzed statistically following the PROC ANOVA procedures. Sediments that were Dredged from LP have high CaCO3 content (82%) and when these Materials were incorporated into existing topsoil they would have the same favorable effects as liming the field. Thus, sediments with high CaCO3 may improve the physical and chemical conditions of subtropical sandy pastures. The heavy and trace metal contents of LDM were below the probable effect levels (PEL) and threshold effect levels (TEL). Average values for Pb, Zn, As, Cu, Hg, Se, Cd, and Ni of 5.2 ± 1.3, 7.0 ± 0.6,4.4 ± 0.1, 8.7 s= 1.2, 0.01 ± 0.02,0.02 ± 0.02,2.5 s 0.1, and 14.6 = 6.4 mg kg-1, respectively, were below the TEL and the PEL. TEL represents the concentrations of sediment-associated contaminants that are considered to cause significant hazards to aquatic organisms, while, PEL represents the lower limit of the range of the contaminant concentrations that are usually or always associated with adverse biological effects. As such, the agricultural or livestock industry could utilize these LDM to produce forages. LDM should be regarded as a beneficiai resource, as a part of the ecological system. Addition of LDM had significant (p ≤ 0.001) effects on soil physico-chemical properties and soil quality. Compared with the control plots, the soils in plots amended with LDM exhibited: (1) lower degree of soil compaction; (2) an increase in soil pH, Ca, and Mg; (3) decrease in the levels of soil Mn, Cu, Fe, Zn, and Si; and (4) no significant change in the level of Na in the soil. Results have shown the favorable influence that LDM had on soil compaction. The treatment x year interaction effect was not significant, but the average soil compaction varied widely (p ≤ 0.001) with LDM application. In 2002 and 2003, soil compaction of plots was lowered significantly as a result of LDM additions. The least compacted soils in 2002 and 2003 were observed from plots with LDM75 with mean soil compaction of 300 × 103 and 350 × 103 Pa, respectively. Beneficial uses of Dredged Materials from LP, Florida are both economical and environmental. Often these Materials can be obtained at little or no cost to the farmers or landowners in south Florida. Environmentally, dredging of sediments that are rich in CaCO3 should restore the 19.4-sq km LP by removing natural sediments from the lake bottom to improve the fishery, water quality, and navigation of the lake. The bottom sediment Materials from lakes, river, and navigational channels usually are composed of upland soil enriched with nutrients and organic matter. These Materials should be regarded as a beneficial resource to be used productively and not to be discarded as spoil Materials. Land application of LDM from LP may not only provide substantial benefits that will enhance the environment, community, and society in south Florida, but also in other parts of the world especially those areas having tropical and subtropical climate with forage-based beef cattle pastures. The heavy and trace metal contents of LDM from LP were below the PEL and TEL. As such, the agricultural or livestock industry could utilize these LDM to produce forages (Part 2 of this study). LDM should be regarded as a beneficial resource, as a part of the ecological system. Further studies are still needed to determine whether the environmental and ecological implications of LDM application are satisfied over the longer term.
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assessing the efficacy of Dredged Materials from lake panasoffkee florida implication to environment and agriculture part 2 pasture establishment and forage productivity
Environmental Science and Pollution Research, 2004Co-Authors: Gilbert C Sigua, Mike L Holtkamp, S W ColemanAbstract: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 (Part 2) were to: (1) assess dredge Materials from Lake Panasoffkee, Florida as a soil amendment to establish bahiagrass (BG) in a subtropical beef cattle pasture in Sumter County, Florida; and (2) determine the effect of LDM application on the crude protein (CP) and nutrient uptake of BG. This series of two papers aims at providing assessment of the efficacy of lake-Dredged Materials especially its implication to environment (soil quality, Part 1) and agriculture (forage quality and pasture establishment. Part 2). The experimental treatments that were evaluated consisted of different ratios of natural soil (NS) to LDM: LDMO (100% NS:0% LDM); LDM25 (75% NS:25% LDM); LDM50 (50% NS:50% LDM); LDM75 (25% NS:75% LDM); and LDM100 (0% NS:100% LDM). Bahiagrass plots at its early establishment were cut to a 5-cm stubble height on Julian days 112 and harvested to the same stubble height on Julian days 238 and on Julian days 546 following the double-ring method. Field layout was based on the principle of a completely randomized block design with four replications. Plant samples harvested at 546 Julian days were ground to pass through a 1-mm mesh screen in a Wiley mill. Ground forage was analyzed for crude protein. Ground forage samples were also analyzed for tissue P, K, Ca, Mg, Mn, Cu, Fe, Al, and Mo concentrations using an ICP spectroscopy. The effects of Dredged Materials addition on forage yield and on crude protein and nutrient uptake that were taken at 546 Julian days were analyzed statistically following the PROC ANOVA procedures. Part 1 of this study demonstrated that the heavy and trace metal contents of LDM were below the probable effect levels and threshold effect levels. As such, the agricultural or livestock industry could utilize these LDM to produce forages. Results showed consistently and significantly (p ≤ 0.001) higher BG biomass production and CP from plots amended with LDM than those of BG planted on plots with 0% LDM. Forage yield of BG during its establishment increased linearly (Forage Yield = 1724.3 + 25.64*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 (LDMO). 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 = 10.38 + 0.052*LDM; R2 = 0.85 p ≤ 0.0001. Addition of LDM had increased the levels of Ca by about 1811 % when compared with the level of soil Ca among plots with no LDM application. Liming the field could have some direct and indirect effects on the chemical status of the soils. The physiological functions performed by Ca in plants are not clearly defined, but it has been suggested that Ca favors the formation of and increases the protein content of mitochondria. Beneficial uses of Dredged Materials from LP, Florida are both economical and environmental. Often these Materials can be obtained at little or no cost to the farmers or landowners. Results showed that Dredged Materials can be used as soil amendments (lime and fertilizer) for early establishment of BG in beef cattle pastures. Environmentally, dredging of sediments that are rich in CaCO3 should restore the 19.4-sq km LP by removing natural sediments from the lake bottom to improve the fishery, water quality, and navigation of the lake. The nutritional uptake of BG grown in unfertile sandy soils of Sumter County was enhanced significantly (p≤0.001) by LDM addition. Uptake of TKN, TP, K, Ca, and Mg were remarkably increased as a result of LDM. Land application of LDM from LP may not only provide substantial benefits that will enhance the environment, community, and society in south Florida, but also in other parts of the world especially those areas with forage-based beef cattle pastures and similar climatic conditions. The heavy and trace metal contents of these Materials were below the PEL and TEL (see Part 1). 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. Although our results have demonstrated the favorable and beneficial effects of added LDM on the early establishment of BG in pasture fields., further studies are still needed not only in pastures of south Florida, but also in other areas with subtropical or tropical climatic conditions to determine whether the environmental and ecological implications of LDM application are satisfied over the longer term.
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land application of lake Dredged Materials for bahiagrass establishment in the subtropical beef pasture
Journal of Soils and Sediments, 2003Co-Authors: Gilbert C Sigua, Mike L Holtkamp, John M Linton, S W ColemanAbstract:The continued need to dredge lakes, rivers, and canals in Florida, both for maintenance and environmental improvement, will produce millions of cubic meters of Dredged Materials. Productive disposal options of lake-Dredged Materials (LDM) may provide substantial and intangible benefits that will enhance the environment, community, and society. The objective of this study was to assess lake-Dredged Materials from Lake Panasoffkee as soil amendment for early establishment of bahiagrass (BG,Paspalum notatum Flugge) in subtropical beef cattle pasture at Sumter County, Florida. Results and Discussion. This study encompassed two phases: Phase 1 comprised of five small observation plots (0.3 x 0.3 m); Phase 2 consisted of five larger test plots (30.5 x 30.5 m). Each of the plots in Phase 1 and Phase 2 had a different ratio LDM to natural soil (NS): Plot 1 (0% LDM + 100% NS); Plot 2 (25% LDM + 75% NS); Plot 3 (50% LDM + 50% NS); Plot 4 (75% LDM + 25% NS); and Plot 5 (100% LDM + 0% NS). Each plot was seeded with BG and early growth and yield establishment were monitored for 16 weeks. Results disclosed significantly taller (p ≤ 0.001) plants and higher biomass production (p ≤ 0.001) of BG from plots amended with 75% LDM than those of BG planted on plots with 0% LDM. Results suggest that LDM can serve as source of lime and fertilizer to establish BG beef pasture fields. Sediments with high CaCO3 improved the physical and chemical conditions of subtropical beef pastures. Lake-Dredged Materials could be removed from the spoil containment areas, trucked to other locations, and incorporated into existing fields for agricultural uses. There is still much to be learned, but it is certain that Lake Panasoffkee sediments should be regarded as a resource, with no observed harmful ecological effects. 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. This study has been continued for several years to explore and assess the long term efficacy of LDM on productivity and quality of BG beyond its early establishment stage.
