The mineral element composition was analyzed for varieties of microgreens, representing 10 species within 6 genera of the Brassicaceae family. Brassicaceae microgreens were assayed for concentrations of macroelements, including calcium (Ca), magnesium (Mg), phosphorous (P), sodium (Na), potassium (K), and of microelements, including copper (Cu), iron (Fe), manganese (Mn), and zinc (Zn). Determinations of mineral elements in microgreen samples were performed using an inductively coupled plasma optical emission spectrophotometer (ICP OES). Potassium was the most abundant macroelement ranging from 176-387 mg/100 g fresh weight (FW), followed by P (52-86 mg/100g FW), Ca (28-66 mg/100g FW), Mg (28-66 mg/100g FW), and Na) 19-68 mg/100g FW. Among the microelements, Fe tended to be most abundant (0.47-0.84 mg/100g FW), followed by Zn (0.22-0.51 mg/100g FW), Mn (0.17-0.48 mg/100g FW), and Cu (0.041-0.13 mg/100g FW). Based upon the analysis of 30 varieties, the results demonstrate that microgreens are good sources of both macroelements (K and Ca) and microelements (Fe and Zn.). Consumption of microgreens could be a health-promoting strategy to meet dietary reference intake requirements for essential elements beneficial to human health.

Poultry production is concentrated on Maryland's eastern shore on areas with sandy soils low in sesquioxideso Water quality has been affected by runoff and leaching of phosphorus from poultry litteramended fields. Phosphorus movement is of major concern because P is a limiting nutrient for eutrophication in surface water. The objectives of this study were to (i) evaluate the ability of AI-rich drinking water treatment residue (DWTR) and iron-rich residue (IRR) reduce water-soluble P and Bray and Kurtz no. 1-extractable phosphorus (BK-1 P) in poultry litter and three long-term litter-amended soils and (it) determine the effects of these residues on pH and electrical conductivity (EC) in the amended litter and soils. Poultry litter and soils were treated with four rates of DWTR and IRR and incubated for 7 wk at 25°C. Litter and soils were sampled at 2, 4, and 7 wk. Both residue materials increased the pH of the litter and the soils. The DWTR was more effective in reducing both water-soluble P and BK-1 P in litter at all rates. At the 25 and 50 g kg-1 rates, reductions in water-soluble P with IRR were comparable with that of DWTR, but DWTR was twice as effeclive as IRR in reducing BK-1 P concentration. The results showed that water-soluble P and BK-I P in poultry litter and long-term litter-amended soils can be substantially reduced by incorporating residues rich in AI and Fe; these residues may be useful for reducing P runoff and leaching from poultry litter and litteramended fields. T HE high demand for poultry products in the USA in recent years has caused a dramatic increase in the growth of the poultry industry (USDA Agricultural Research Service, 1997, p. 26-54). Increased poultry production has, in turn, resulted in a corresponding increase in the amount of poultry litter (manure mixed with straw, wood chips, sawdust, or peanut hulls) that must be disposed of. Maryland, a state with a long history of poultry production, currently ranks seventh in the nation in broiler production. Maryland produced 636 million kg of broilers (live weight) in 1996 that generated approximately 400 million kg of litter (Maryland Agricultural Statistics Service, 1996). Poultry litter typically contains 8 to 25.8 g P kg-1 dry weight, with about 4.9 g P kg-1 being water-soluble reactive P, because P is added to chicken (Gallus gallus) diets to ensure rapid growth (Edwards and Daniel, 1992). Most of the poultry litter produced in Maryland has been applied to relatively small areas of cropland in close proximity to the chicken houses (Sims and Wolf, 1994). Many of the soils in the poultry production areas of Maryland are coarse textured, low in clay and sesquioxides, which are important in immobilizing P, and have shallow water tables (Mozaffari and Sims, 1994). Re

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The Choptank River is an estuary, tributary of the Chesapeake Bay, and an ecosystem in decline due partly to excessive nutrient and sediment loads from agriculture. The Conservation Effects Assessment Project for the Choptank River watershed was established to evaluate the effectiveness of conservation practices on water quality within this watershed. Several measurement frameworks are being used to assess conservation practices. Nutrients (nitrogen and phosphorus) and herbicides (atrazine and metolachlor) are monitored within 15 small, agricultural subwatersheds and periodically in the lower portions of the river estuary. Initial results indicate that land use within these subwatersheds is a major determinant of nutrient concentration in streams. In addition, the 18 O isotope signature of nitrate was used to provide a landscape assessment of denitrification processes in the presence of the variable land use. Herbicide concentrations were not correlated to land use, suggesting that herbicide delivery to the streams is influenced by other factors and/or processes. Remote sensing technologies have been used to scale point measurements of best management practice effectiveness from field to subwatershed and watershed scales. Optical satellite (SPOT-5) data and ground-level measurements have been shown to be effective for monitoring nutrient uptake by winter cover crops in fields with a wide range of management practices. Synthetic Aperture Radar (RADARSAT-1) data have been shown to detect and to characterize accurately the hydrology (hydroperiod) of forested wetlands at landscape and watershed scales. These multiple approaches are providing actual data for assessment of conservation practices and to help producers, natural resource managers, and policy makers maintain agricultural production while protecting this unique estuary.

Maryland will impose restrictions on poultry litter application to soils with excessive P by the year 2005. Alternative uses for poultry litter are being considered, including burning as a fuel to generate electricity. The resulting ash contains high levels of total P, but the availability for crop uptake has not been reported. Our objective was to compare the effectiveness of poultry litter ash (PLA) and potassium phosphate (KP) as a P source for wheat (Triticum aestivum L.) in acidic soils, without and with limestone application. Two acidic soils (pH 4.25 and 4.48) were studied, unlimed or limed to pH 6.5 before cropping. The PLA and KP were applied at 0, 39, and 78 kg P ha(-1), after which wheat was grown. Limestone significantly increased wheat yield, but the P sources without limestone did not. The two P sources were not significantly different as P fertilizer. At the 78 kg P ha(-1) rate, wheat shoot-P concentrations were 1.10 and 1.12 g kg(-1) for the PLA treatment compared with 0.90 and 0.89 g kg(-1) for KP in the nonlimed and limed soils, respectively. Trace element concentrations in wheat shoots from the PLA treatment were less than or equal to KP and the control. The low levels of water-soluble P and metals in the soils and the low metal concentrations in wheat suggest that PLA is an effective P fertilizer. Further studies are needed to determine the optimum application rate of PLA as a P fertilizer.

A greater understanding of the spatial patterns of water inputs to soil will aid the development of agricultural practices to reduce leaching and runoff of agrochemicals. This study was initiated to investigate the process of stemflow, and to provide quantitative data on the distribution of rainfall under a corn (Zea mays L.) canopy. Rainfall distribution under the canopies of replicate conventional till corn plots was investigated by placing rainfall collectors at discrete locations within smalll.6-m by 0.76-m areas of the plots. Collection cups were also fixed around the stalks of individual corn plants to quantify stemflow. Results obtained from eight storm events in 1987 revealed that corn plants channel 19 to 49% of the total rain inputs down the stem to the base of the stalk. This stemflow plus the rainfall impinging directly in the planting furrow, accounted for approximately 42% of the total water inputs from a given storm event. These increased water inputs to the planting furrow may have implications in modeling solute leaching and runoff as well as to modifying current fertilizer and pesticide application methods.

In 2005, the U.S. Environmental Protection Agency (USEPA) National Menu of Best Management Practices (BMPs) listed compost filter socks (FS) as an approved BMP for controlling sediment in storm runoff on construction sites. The objectives of this study were to determine if FS with or without the addition of a flocculation agent to the FS system can significantly remove (i) suspended clay and silt particulates, (ii) ammonium nitrogen (NH(4)-N) and nitrate-nitrite nitrogen (NO(3)-N), (iii) fecal bacteria, (iv) heavy metals, and (v) petroleum hydrocarbons from storm water runoff. Five separate (I-V) 30-min simulated rainfall-runoff events were applied to soil chambers packed with Hartboro silt loam (fine-loamy, mixed, active, nonacid, mesic fluvaquentic Endoaquepts) or a 6-mm concrete veneer on a 10% slope, and all runoff was collected and analyzed for hydraulic flow rate, volume, pollutant concentrations, pollutant loads, and removal efficiencies. In corresponding experiments, runoff was analyzed for (i) size of sediment particles, (ii) NH(4)-N and NO(3)-N, (iii) total coliforms (TC) and Escherichia coli, (iv) Cd, Cr, Cu, Ni, Pb and Zn, and (v) gasoline, diesel, and motor oil, respectively. Results showed that: (i) FS removed 65% and 66% of clay (<0.002 mm) and silt (0.002-0.05 mm), respectively; (ii) FS removed 17%, and 11% of NH(4)-N and NO(3)-N, respectively and when NitroLoxx was added to the FS, removal of NH(4)-N load increased to 27%; (iii) total coliform and E. coli removal efficiencies were 74 and 75%, respectively, however, when BactoLoxx was added, removal efficiency increased to 87 and 99% for TC and 89 and 99% for E. coli, respectively; (iv) FS removal efficiency for Cd, Cr, Cu, Ni, Pb, and Zn ranged from 37 to 72%, and, when MetalLoxx was added, removal efficiency ranged from 47 to 74%; and (v) FS removal efficiency for the three petroleum hydrocarbons ranged from 43 to 99% and the addition of PetroLoxx increased motor oil and gasoline removal efficiency in the FS system.