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Copper Sulfate Foot Baths on Dairies and Crop Toxicities – What are the Risks?
Get PDFA rising concern with the application of dairy wastes to agricultural fields is the accumulation of
copper (Cu) in the soil. Copper
sulfate (CuSO4) from cattle foot
baths are washed out of dairy
barns and into wastewater lagoons. The addition of CuSO4
baths has been reported to increase Cu concentration significantly in manure slurry from 4.8
g/1000 L to 88.6 g/1000 L (Miner
Institute, New York). The Cu-enriched dairy waste is then applied to agricultural crops, thus raising concerns about how soils and
plants are impacted by these Cu additions
Completely automated open-path FT-IR spectrometry
Get PDFAtmospheric analysis by open-path Fourier-transform
infrared (OP/FT-IR) spectrometry has been
possible for over two decades but has not been widely
used because of the limitations of the software of commercial
instruments. In this paper, we describe the current state-of-
the-art of the hardware and software that constitutes a
contemporary OP/FT-IR spectrometer. We then describe
advances that have been made in our laboratory that have
enabled many of the limitations of this type of instrument to
be overcome. These include not having to acquire a single-beam
background spectrum that compensates for absorption
features in the spectra of atmospheric water vapor and carbon
dioxide. Instead, an easily measured “short path-length”
background spectrum is used for calculation of each
absorbance spectrum that is measured over a long pathlength.
To accomplish this goal, the algorithm used to
calculate the concentrations of trace atmospheric molecules
was changed from classical least-squares regression (CLS)
to partial least-squares regression (PLS). For calibration,
OP/FT-IR spectra are measured in pristine air over a wide
variety of path-lengths, temperatures, and humidities,
ratioed against a short-path background, and converted to
absorbance; the reference spectrum of each analyte is then
multiplied by randomly selected coefficients and added to
these background spectra. Automatic baseline correction for
small molecules with resolved rotational fine structure, such
as ammonia and methane, is effected using wavelet transforms.
A novel method of correcting for the effect of the
nonlinear response of mercury cadmium telluride detectors
is also incorporated. Finally, target factor analysis may be
used to detect the onset of a given pollutant when its
concentration exceeds a certain threshold. In this way, the
concentration of atmospheric species has been obtained
from OP/FT-IR spectra measured at intervals of 1 min over a
period of many hours with no operator intervention
Identification of differentially expressed UniGenes in developing wheat seed using digital differential display
Get PDFThe wheat UniGene sets, derived from over one million Expressed Sequence Tags (ESTs) in the NCBI
GenBank, offer a platform for identifying differentially expressed genes in wheat seeds. This report
illustrates a means to efficiently utilize this public database for gene expression (transcriptome) profiling
of developing wheat seed. Using a data mining tool known as Digital Differential Display (DDD), thirteen
pair-wise comparisons were performed on seven seed cDNA libraries from five varieties at various seed
development stages. DDD identified 46 seed-specific UniGene sets, excluding the well characterized
‘‘housekeeping’’ and seed storage protein genes. Additionally, seed- and developmentally-specific
UniGenes were identified. Some of these genes encode for proteins such as purothionins, serpins,
a-amylase inhibitors, lipid transfer proteins, and other unknown but novel gene sequences. Specifically,
the wheat serpin and b-purothionin precursor were found to be expressed at higher levels in hard
varieties than soft varieties. This study supports the starting premise that by implementing in-silico
analysis of the wheat UniGene database, it is possible to rapidly create transcriptional profiles of known
and novel genes in developing seeds
Long-term polyacrylamide formulation effects on soil erosion, water infiltration, and yields of furrow-irrigated crops
Get PDFTwo formulations of water-soluble anionic polyacrylamide (WSPAM) are used in agriculture to reduce erosion and manage
infiltration in furrow irrigations, although few if any reports have compared their effectiveness. A control and two WSPAMs, a
granular form and the inverse emulsion, or oil-based liquid form, were applied to irrigation water supplied to furrows formed in
a silt loam soil with 1.5% slope during each irrigation from 1993 to 1999. Stock solutions prepared from the two WSPAMs in tap
water were injected into furrow inflows to attain a concentration of 10 mg L−1 only during furrow advance. During irrigations,
furrow inflow and runoff rates, and runoff sediment concentrations were measured. Crop yields were measured in five of the 7
yr. Relative to controls, both WSPAM treatments reduced runoff sediment loss equally well, decreasing soil losses by 84% per
irrigation, and prevented the loss of 47.8 Mg soil ha−1 over the 7-yr period. The yearly soil loss reductions produced by WSPAMs
ranged from 66 to 99%, and may reflect changes in the electrical conductivity (EC) of the irrigation water. Both WSPAM treatments
increased the proportion of applied irrigation water that infiltrated into newly formed furrows, but the emulsion produced
the greatest overall increase in water infiltration fraction. As a class, WSPAM treatments increased yields by 14.3% for bean
(‘Viva Pink’ Phaseolus vulgaris L.) and 4.5% for silage corn (Zea mays L.), suggesting that the cost of WSPAM applications may
be recoverable. While the two WSPAM formulations provide equivalent erosion protection, differences in infiltration effects,
product costs, and potential environmental impacts should be considered when selecting the formulation
Case Study: Seasonal and Spatial Distribution of Ambient Ammonia Concentrations Measured at a Large Open-Lot Dairy
Get PDFThe volatilization of NH3 from dairy production facilities is not only a loss of valuable N, but also an air quality concern because NH3 plays a role in the formation of airborne particulate matter, which can be a health hazard. The ambient NH3 concentrations over several seasons at 3 locations (open lots, compost yard, lagoon) throughout a large openlot dairy were determined, as well as the spatial distribution of NH3 over the open-lot area. There was a significant main effect of location (P lagoon = compost > background, with averages of 0.58, 0.33, 0.30, and 0.04 mg NH3/m3, respectively. The effect of weather and lot conditions on the spatial distribution of NH3 across the lots was evident, with lower concentrations and less spatial variability in winter months when the lots were frozen compared with wetter warmer months. Lower NH3 concentrations and less spatial variability were also measured when manure stockpiles were removed from the open lots and the lots were dry. Significantly greater NH3 concentrations were generated in the lot area versus the compost and lagoon areas, which were not significantly different. Because the lots are greater in size by a factor of approximately 6, it is evident that NH3 emissions from this sector of the dairy contribute the greatest amount of NH3 to the atmosphere
Center-pivot irrigation system for independent site-specific management of water and chemical application
Get PDFThe development of lateral‐move and center‐pivot irrigation systems equipped for spatially variable water
application and those equipped with an independent chemical application system have largely evolved independently.
Integration of independent site‐specific water and chemical application with lateral‐move and center‐pivot irrigation systems
has received little attention. Increasing the utility of site‐specific management technologies added to automated irrigation
systems will increase their cost effectiveness and commercial potential. An independent chemical application system capable
of variable rate application was installed and tested on a 4‐span center‐pivot irrigation system equipped for variable rate
water application. The chemical application system was assembled using mini‐sprinklers and common commercial irrigation
system components. For uniform chemical application, the coefficient of uniformity (CU) values ranged from 84 to 90
providing acceptable application uniformity. For variable rate chemical application, CU values ranged from 79 to 93 and
measured mean area‐weighted relative application values were well correlated with target relative application values with
R2 of 0.9 or higher. Field testing of the chemical application system demonstrated that it can be used to effectively apply
spatially variable chemical application concurrent and independent of spatially variable water application
Soil water measurements relevant to agronomic and environmental functions of chemically treated soil
Get PDFModern agricultural, turf, and landscape management routinely apply and depend upon
chemical applications to optimize system function for specific outcomes. The effectiveness of these applied
chemicals to achieve desired outcomes usually depends upon their interaction with and transport by water.
To fully and accurately assess the role of water as a chemical delivery and activation system requires a
good understanding of how the applied chemicals, soil, and water interact, the scale at which a phenomenon
is important, the nature of soil variability, and which of the three dominant soil water properties
�content, movement, or potential energy� is most suited to assessing water’s role. The science of this
assessment process is extensive and its literature is voluminous. For the uninitiated, however, it is worth
being aware at least of the basics of soil water assessment and where some of the pitfalls lie. This
presentation describes soil as a three-phase system �solids, liquid, and gases� and highlights some of the
key measurements and measurement considerations necessary to appropriately characterize treatment
efficacy for specific, and especially, non-intuitive effects. The presentation cannot be comprehensive or
substitute for requisite university-level courses in soil physics and soil chemistry, but can, perhaps, alert
applicators to situations and considerations that demand more than mere cursory assessment for proper
evaluation and interpretation
Determination of kinetic energy applied by center pivot sprinklers
Get PDFThe kinetic energy of discrete drops impacting a bare soil surface is generally observed to lead to a drastic reduction in water infiltration rate due to soil surface seal formation. Under center pivot sprinkler irrigation, kinetic energy transferred to the soil prior to crop canopy development can have a substantial effect on seasonal runoff and soil erosion. In the design of center pivot irrigation systems, selection of sprinklers with minimum applied kinetic energy could potentially minimize seasonal runoff and erosion hazard. Size and velocity of drops from five common center pivot sprinklers were measured using a laser in the laboratory. The data were used to calculate kinetic energy transferred to the soil by each sprinkler on a center pivot irrigation system lateral with 2.5 m spacing between sprinklers. Specific power, which represents the rate that kinetic energy is transferred to the soil as a function of distance from a sprinkler and analogous to a sprinkler radial water application rate distribution, was used to estimate actual kinetic energy transferred to the soil by overlapping specific power profiles of sprinklers equally spaced along a center pivot lateral. Kinetic energy of irrigation sprinklers has traditionally been characterized using area weighted kinetic energy per unit drop volume. This characterization was found not to be correlated to actual kinetic energy transferred to the soil by the sprinklers. The results demonstrated that sprinklers with the smallest drop sizes do not necessarily transfer the least kinetic energy per unit depth of water applied. Conversely, sprinklers with the largest drop sizes do not necessarily transfer the greatest kinetic energy to the soil
Impact of sheep bedding on soil nutrient dynamics in the Centennial Mountains of Montana and Idaho
Get PDFSheep and lamb production is an important industry in Idaho, with
summer sheep grazing in the mountains a common practice. Sheep are
concentrated in bedding areas at night leading to concentrated grazing
and manure and urine accumulation in these areas. To address the effects
of bedding on soil nutrient status, we monitored 16 bedding areas in the
Centennial Mountains, with a general survey performed in 2004 followed
by more intense monitoring of six sites from 2005 to 2006. In 2004, soils
were analyzed for total carbon (C) and nitrogen (N), organic C, total P,
Olsen P, water-soluble phosphorus (WSP), soluble nitrate, and soluble
ammonium. Over the period 2005–2006, soils were analyzed for soluble
nutrients including Olsen P, WSP, soluble nitrate, and soluble ammonium.
The 16 sites evaluated in 2004 had significantly greater total N, C,
and organic C concentrations in the nonbedded areas, whereas Olsen P,
WSP, and ammonium concentrations were greater in the bedding areas.
When six sites were monitored over time, there was no significant effect
of bedding on soluble P concentrations over time or between bedding
and control areas, whereas there was a significant effect of time on
soluble N concentrations but no significant differences between bedding
and control areas. Although these results are preliminary, it seems as if
sheep bedding can alter the nutrient content of soils increasing some
measures of soil nutrients, while decreasing others, which ultimately can
affect the productivity and plant species diversity in these areas
The effects of phytase supplementation on performance and phosphorus excretion from broiler chickens fed low phosphorus-containing diets based on normal or low-phytic acid barley
Get PDFA total of 240 day-old broiler chicks were used to study the effects of phytase on performance and phosphorus (P)
excretion from birds fed diets containing low phytate barleys formulated without inorganic P. A positive control based on Harrington
barley (HB) was formulated to meet requirements for total P. Three experimental diets, based on either HB (0.39% total P with 0.28%
phytate P) or the low phytate varieties LP 422 (0.36% total P with 0.14% phytate P) and LP 955 (0.40% total P with 0.0 I% phytate P),
were formulated to be below requirements for total P by removing all the inorganic P from the diet. The four diets were fed with and
without 1,000 FTU/kg phytase. Apparent P digestibility was significantly higher (p<0.01) for birds fed the low phytate barleys than for
birds fed HB either supplemented or un-supplemented with inorganic P. P excretion was significantly lower (p<0.01)for birds fed HB
without inorganic P than with inorganic P. P excretion was further reduced by the use of the low phytate barleys LP 422 and LP 455
(p<0.01).Phytase supplementation did not affect P excretion (p = 0.39). Body weight gain and feed intake were highest for birds fed the
HB diet with inorganic P and lowest for birds fed the HB diet without inorganic P (p<0.01). Among the three low P diets, body weight
gain and feed intake of broilers increased as the level of phytate in the barley declined (p<0.01).Phytase modestly increased body
weight gain (p = 0.08) and feed intake (p = 0.04). The overall results of this study indicate that it may be possible to reduce the amount
of inorganic P used when formulating diets with low phytate barley compared with the levels needed when formulating diets with
normal phytate barley. However, it is not possible to completely replace the inorganic P in diets containing low phytate barley without
impairing poultry performance. Feeding diets devoid of supplementary inorganic P in combination with low phytate barley resulted in a
significant reduction in P excretion by poultry