Salinization and sodicity are obstacles for vegetation reconstruction of coastal tidal flat soils. A study was conducted with flue gas desulfurization（FGD）-gypsum applied at rates of 0, 15, 30, 45 and 60 Mg/ha to re...Salinization and sodicity are obstacles for vegetation reconstruction of coastal tidal flat soils. A study was conducted with flue gas desulfurization（FGD）-gypsum applied at rates of 0, 15, 30, 45 and 60 Mg/ha to remediate tidal flat soils of the Yangtze River estuary.Exchangeable sodium percentage（ESP）, exchangeable sodium（ExNa）, p H, soluble salt concentration, and composition of soluble salts were measured in 10 cm increments from the surface to 30 cm depth after 6 and 18 months. The results indicated that the effect of FGD-gypsum is greatest in the 0–10 cm mixing soil layer and 60 Mg/ha was the optimal rate that can reduce the ESP to below 6% and decrease soil p H to neutral（7.0）. The improvement effect was reached after 6 months, and remained after 18 months. The composition of soluble salts was transformed from sodic salt ions mainly containing Na~＋, HCO_3^-＋ CO_3^（2-）and Cl-to neutral salt ions mainly containing Ca^（2＋）and SO_4^（2-）. Non-halophyte plants were survived at 90%. The study demonstrates that the use of FGD-gypsum for remediating tidal flat soils is promising.展开更多
Compaction due to urbanization and farm operations disrupt natural soil profiles,increase impervious surface areas and decrease vegetative cover.These disruptions increase storm-water runoff at the expense of ground w...Compaction due to urbanization and farm operations disrupt natural soil profiles,increase impervious surface areas and decrease vegetative cover.These disruptions increase storm-water runoff at the expense of ground water recharge,degrading water quality and impairing aquatic habitats.A completely randomized experiment was conducted at the OSU/South Centers,Piketon,OH to assess the effect of Daikon radish(Raphanus sativus L.var.oleiferus)on alleviating compaction.Treatments included long-term tillage,long-term no-till(NT)and a fallow soil compacted with farm equipment with and without Daikon radish.Radish was sown in mid-August and plants were winter-killed at the onset of first frost when the temperature dropped to-2.22°C(28°F).To assess progress in compaction alleviation,a model was developed to extrapolate information on soil porosity as an indicator of hydrological properties of soils.Earthworm population dynamics were also considered as a bio-indicator of compaction alleviation.The adoption of radish used as bio-drilling,alleviated overall compaction by 40%with reductions ranging from 90%at 0-13 cm to 30%at 56-64 cm depth.The fallow compacted soil with radish had the highest population of earthworm with total body mass of 3.6 kg·m-3,followed by NT at 0.8 kg·m^-3,and till at 0.4 kg·m^-3(p<0.05).Mean values of soil porosity were increased by 44%with radish compared to the fields without radish.This increase ranged from 71%in the upper soil depths(0-13 cm depth)to 25%in the lower depths(56-64 cm depths).Use of bio-drilling has potential to synergistically alleviate the effect of compaction,minimize flash-flooding and improve water quality.展开更多
Controlling dissolved phosphorus(DP)loss from high P soil to avoid water eutrophication is a worldwide high priority.A greenhouse study was conducted in which flue gas desulfurization gypsum(FGDG)was applied by using ...Controlling dissolved phosphorus(DP)loss from high P soil to avoid water eutrophication is a worldwide high priority.A greenhouse study was conducted in which flue gas desulfurization gypsum(FGDG)was applied by using different application methods and rates to two agricultural soils.Phosphorus fertilizer was incorporated into the soils at 2.95 g kg^(-1)to simulate soil with high P levels.The FGDG was then applied at amounts of 0,1.5,and 15 g kg^(-1)soil on either the soil surface or mixed throughout the soil samples to simulate no-tillage and tillage,respectively.Ryegrass was planted after treatment application.The study showed that FGDG reduced runoff DP loss by 33%and leachate DP loss 38%in silt loam soil,and runoff DP loss 46%and leachate DP loss 14%in clay loam soil,at the treatment of 15 g kg^(-1)FGDG.Mixing applied method(tillage)provided strong interaction with higher FGDG.To overall effect,the mixing-applied method performed better in controlling DP loss from silt loam soil,while surface-applied(no tillage)showed its advantage in controlling DP loss from clay loam soil.In practice it is necessary to optimize FGDG concentrations,application methods,and DP sources(runoff or leachate)to get maximized benefits of FGDG application.The FGDG application had no negative effects on the soil and ryegrass.展开更多
Conservation practices are encouraged to improve soil health and sustain agronomic crop production.Mehlich-3 is often used as a multi-nutrient extractant to determine soil fertility status.A study inves-tigated the im...Conservation practices are encouraged to improve soil health and sustain agronomic crop production.Mehlich-3 is often used as a multi-nutrient extractant to determine soil fertility status.A study inves-tigated the impacts of the conservation practices of gypsum,cover crops,and crop rotation on 28 Mehlich-3 extractable elements,of which 11 were considered plant nutrients,from soil at three mid-western US locations.Soil was collected from 0 to 15 and 15-30 cm depths 5 years after implementing the conservation practices.Treatments consisted of(1)with and without cereal rye(Secale cereale L.)winter cover,(2)continuous soybean[Glycine max(L.)Merr.]vs.soybean-corn(Zea mays L.)rotation,and(3)annual gypsum application(0,1.1,and 2.2 Mg ha-1).Differences were observed by site,depth,and conservation practice depending on the element evaluated.Minimal interactive effects were observed among treatments.The most consistent effect was observed for crop rotation across sites.Gypsum only affected the site with the greatest clay content,where more Ca and S were retained,and Mg and Mn displaced.Cover crop only affected elements at this high clay site,where different elements were positively or negatively affected.Results suggest that not one practice fits all,and optimum conservation practices must be tailored for the site.展开更多
基金supported by the National Public Project of Environmental Protection(No.201109023)the Shanghai Agricultural Committee(No.2012-2-1)
文摘Salinization and sodicity are obstacles for vegetation reconstruction of coastal tidal flat soils. A study was conducted with flue gas desulfurization（FGD）-gypsum applied at rates of 0, 15, 30, 45 and 60 Mg/ha to remediate tidal flat soils of the Yangtze River estuary.Exchangeable sodium percentage（ESP）, exchangeable sodium（ExNa）, p H, soluble salt concentration, and composition of soluble salts were measured in 10 cm increments from the surface to 30 cm depth after 6 and 18 months. The results indicated that the effect of FGD-gypsum is greatest in the 0–10 cm mixing soil layer and 60 Mg/ha was the optimal rate that can reduce the ESP to below 6% and decrease soil p H to neutral（7.0）. The improvement effect was reached after 6 months, and remained after 18 months. The composition of soluble salts was transformed from sodic salt ions mainly containing Na~＋, HCO_3^-＋ CO_3^（2-）and Cl-to neutral salt ions mainly containing Ca^（2＋）and SO_4^（2-）. Non-halophyte plants were survived at 90%. The study demonstrates that the use of FGD-gypsum for remediating tidal flat soils is promising.
文摘Compaction due to urbanization and farm operations disrupt natural soil profiles,increase impervious surface areas and decrease vegetative cover.These disruptions increase storm-water runoff at the expense of ground water recharge,degrading water quality and impairing aquatic habitats.A completely randomized experiment was conducted at the OSU/South Centers,Piketon,OH to assess the effect of Daikon radish(Raphanus sativus L.var.oleiferus)on alleviating compaction.Treatments included long-term tillage,long-term no-till(NT)and a fallow soil compacted with farm equipment with and without Daikon radish.Radish was sown in mid-August and plants were winter-killed at the onset of first frost when the temperature dropped to-2.22°C(28°F).To assess progress in compaction alleviation,a model was developed to extrapolate information on soil porosity as an indicator of hydrological properties of soils.Earthworm population dynamics were also considered as a bio-indicator of compaction alleviation.The adoption of radish used as bio-drilling,alleviated overall compaction by 40%with reductions ranging from 90%at 0-13 cm to 30%at 56-64 cm depth.The fallow compacted soil with radish had the highest population of earthworm with total body mass of 3.6 kg·m-3,followed by NT at 0.8 kg·m^-3,and till at 0.4 kg·m^-3(p<0.05).Mean values of soil porosity were increased by 44%with radish compared to the fields without radish.This increase ranged from 71%in the upper soil depths(0-13 cm depth)to 25%in the lower depths(56-64 cm depths).Use of bio-drilling has potential to synergistically alleviate the effect of compaction,minimize flash-flooding and improve water quality.
基金supported by the China Scholarship Council(201306140128)the Young Scientist Fund of the National Natural Science Foundation of China(31901207)by state and federal funds appropriated to The Ohio State University and The Ohio Agricultural Research and Development Center,Wooster,OH,USA.The funders had no role in study design,data collection and analysis,decision to publish,or preparation of the manuscript.
文摘Controlling dissolved phosphorus(DP)loss from high P soil to avoid water eutrophication is a worldwide high priority.A greenhouse study was conducted in which flue gas desulfurization gypsum(FGDG)was applied by using different application methods and rates to two agricultural soils.Phosphorus fertilizer was incorporated into the soils at 2.95 g kg^(-1)to simulate soil with high P levels.The FGDG was then applied at amounts of 0,1.5,and 15 g kg^(-1)soil on either the soil surface or mixed throughout the soil samples to simulate no-tillage and tillage,respectively.Ryegrass was planted after treatment application.The study showed that FGDG reduced runoff DP loss by 33%and leachate DP loss 38%in silt loam soil,and runoff DP loss 46%and leachate DP loss 14%in clay loam soil,at the treatment of 15 g kg^(-1)FGDG.Mixing applied method(tillage)provided strong interaction with higher FGDG.To overall effect,the mixing-applied method performed better in controlling DP loss from silt loam soil,while surface-applied(no tillage)showed its advantage in controlling DP loss from clay loam soil.In practice it is necessary to optimize FGDG concentrations,application methods,and DP sources(runoff or leachate)to get maximized benefits of FGDG application.The FGDG application had no negative effects on the soil and ryegrass.
基金support provided by United Soybean Board Project Number 1520-732-7226by state and federal funds appropriated to The Ohio State University and The Ohio Agricultural Research and Development Center。
文摘Conservation practices are encouraged to improve soil health and sustain agronomic crop production.Mehlich-3 is often used as a multi-nutrient extractant to determine soil fertility status.A study inves-tigated the impacts of the conservation practices of gypsum,cover crops,and crop rotation on 28 Mehlich-3 extractable elements,of which 11 were considered plant nutrients,from soil at three mid-western US locations.Soil was collected from 0 to 15 and 15-30 cm depths 5 years after implementing the conservation practices.Treatments consisted of(1)with and without cereal rye(Secale cereale L.)winter cover,(2)continuous soybean[Glycine max(L.)Merr.]vs.soybean-corn(Zea mays L.)rotation,and(3)annual gypsum application(0,1.1,and 2.2 Mg ha-1).Differences were observed by site,depth,and conservation practice depending on the element evaluated.Minimal interactive effects were observed among treatments.The most consistent effect was observed for crop rotation across sites.Gypsum only affected the site with the greatest clay content,where more Ca and S were retained,and Mg and Mn displaced.Cover crop only affected elements at this high clay site,where different elements were positively or negatively affected.Results suggest that not one practice fits all,and optimum conservation practices must be tailored for the site.
