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The effectiveness of recovered magnesium phosphates as fertilizers in neutral and slightly alkaline soils
Get PDFMagnesium phosphates such as struvite (MgNH4PO4x6H2O) can be recovered from municipal, industrial and agricultural wastewaters. However, minimal research has been conducted on the beneficial reuse of these recovered products; conducted research has focused on low pH soils. This study determined whether recovered struvite and dittmarite (MgNH4PO4xH2O) were effective P fertilizers in alkaline soils. In addition to commercially available triple superphosphate (TSP) and certified organic rock phosphate (RP), recovered struvite, dittmarite, and a heterogeneous recovered phosphate were evaluated in a laboratory dissolution study and as fertilizers for spring wheat (Triticum aestivum L.) in a greenhouse study. Struvite and dittmarite were much more soluble than RP, but less soluble than TSP. Laboratory dissolution kinetics were fast, with most materials nearing equilibrium within 24 hours. At a soil pH of 6.5, both dittmarite and struvite increased the average plant P concentration over the control. Struvite and dittmarite performance was similar to TSP. There were no significant differences in plant dry matter (DM) production or total P uptake at pH 6.5. In the limed soil (pH 7.6), many treatments had plant P concentrations significantly lower than the control, but most fertilizers increased DM production over the control; all fertilizers generally performed similarly to one another. These findings support previous work showing recovered Mg phosphates to be effective in acidic soils, and provide evidence that they are also effective in alkaline soils. Recovered Mg phosphates could become a useful alternative for P fertilization in arid and semi-arid environments
Effectiveness of recovered magnesium phosphates as fertilizers in neutral and slightly alkaline soils
Get PDFMagnesium phosphates such as struvite (MgNH4PO4 · 6H2O) can be recovered from municipal, industrial, and agricultural
wastewaters. However, limited information is available on the beneficial reuse of these recovered products; research has focused
on low pH soils. Th is study determined whether recovered struvite and dittmarite (MgNH4PO4 · H2O) were effective P fertilizers
in neutral to slightly alkaline soils. In addition to commercially available triple superphosphate (TSP) and certified organic
rock phosphate (RP), recovered struvite, dittmarite, and a heterogeneous recovered phosphate were evaluated in a laboratory
dissolution study and as fertilizers for spring wheat (Triticum aestivum L.) in a greenhouse study. Struvite and dittmarite were
much more soluble than RP, but less soluble than TSP. Laboratory dissolution kinetics were fast, with most materials nearing
equilibrium within 7 to 14 d. At a soil pH of 6.5, both dittmarite and struvite increased the average plant P concentration over the
control. Struvite and dittmarite performance was similar to TSP. There were no significant differences in plant dry matter (DM)
production or total P uptake at pH 6.5. In the limed soil (pH 7.6), many treatments had plant P concentrations significantly lower
than the control, but most fertilizers increased DM production over the control; all fertilizers generally performed similarly to
one another. These findings support previous work showing recovered Mg phosphates to be effective in acidic soils, and provide
evidence that they are also effective in slightly alkaline soils. Recovered Mg phosphates could become a useful alternative for P
fertilization in arid and semiarid environments
Experimental sugar beet cultivars evaluated for rhizomania resistance and storability in Idaho, 2008
Get PDFThirty-five experimental and four commercial check sugar beet cultivars were evaluated in a commercial sprinklerirrigated
sugar beet field near Jerome, ID where winter wheat was grown in 2007. The field trial relied on natural infection
for rhizomania development. The plots were planted on 22 Apr 08 to a density of 142,560 seeds/A, and thinned to 47,520
plants/A on 30 May. Plots were four rows (22-in. row spacing) and 34.5 ft long. The experimental design was a randomized
complete block design with four replications per cultivar. The crop was managed according to standard cultural practices.
The roots were mechanically topped and the center two rows were collected with a mechanical harvester on 9 Oct. At
harvest the roots were evaluated for rhizomania (Rz rating) using a scale of 0-9 (0 = healthy and 9 = dead). The percent
sucrose at harvest was established based on two eight-root samples from each plot. The samples were submitted to the
Amalgamated Tare Lab (determined percent sucrose, conductivity, nitrates, and tare). At harvest, eight roots per plot were
also placed in a mesh onion bag, weighed, and placed in an indoor commercial sugar beet storage facility on 9 Oct set to hold
35°F. On 29 Jan 09, the roots were evaluated for the percentage of surface area covered by fungal growth (an undescribed
basidiomycete that correlates with sucrose loss in storage). On 2 Feb 09 roots were retrieved after 115 days in storage and
evaluated for weight and percent sucrose (via gas chromatography). To establish percent reduction in sucrose at harvest
versus storage only samples from the same plots were compared. Data were analyzed using the general linear models
procedure (Proc GLM-SAS), and Fisher’s protected least significant difference was used for mean comparisons
The characterization and composition of bacterial communities in soils blended with spent foundry sand
Get PDFThe purpose of this research was to characterize the structure and composition of bacterial communities in
sandy loam and silty clay soils amended with 30% spent sand from iron, aluminum, and steel foundries. All spent foundry
sand (SFS) blends were grown with or without perennial ryegrass and samples were collected at 4 weeks and 6 months.
Regions of the 16S rRNA gene were amplified using PCR and subsequently analyzed by DGGE and sequenced for bacterial
identification and phylogenetic classification. Cluster analyses of PCR-DGGE banding patterns revealed that SFS blends
from week 4 and month 6 produced unique clusters, with most ryegrass treatments clustering away from those without
ryegrass. The diversity of the bacterial community revealed that it was generally higher in the SFS blends without ryegrass.
By month 6 in treatments without ryegrass, the diversity in the sandy loam blends was similar to the control, while the
diversity in all silty clay blends was greater than the control. Phylogenetic analysis of bacterial isolates (total of 309) from
the SFS blends showed that they were dominated by Actinobacteria (46%), Proteobacteria (29%), and Bacilli (20%), with
fewer numbers belonging to Bacteroidetes (5%). While the addition of SFS to soil does bring about bacterial community
level changes, these changes are similar to that of blending soil with clean silica sand
Selenium adsorption to aluminum-based water treatment residuals
Get PDFAluminum-based water treatment residuals (WTR) can adsorb water- and soil-borne P, As(V), As(III), and
perchlorate, and may be able to adsorb excess environmental selenium. WTR, clay minerals, and amorphous
aluminum hydroxide were shaken for 24 h in selenate or selenite solutions at pH values of 5–9,
and then analyzed for selenium content. Selenate and selenite adsorption edges were unaffected across
the pH range studied. Selenate adsorbed on to WTR, reference mineral phases, and amorphous aluminum
hydroxide occurred as outer sphere complexes (relatively loosely bound), while selenite adsorption was
identified as inner-sphere complexation (relatively tightly bound). Selenite sorption to WTR in an anoxic
environment reduced Se(IV) to Se(0), and oxidation of Se(0) or Se(IV) appeared irreversible once sorbed to
WTR. Al-based WTR could play a favorable role in sequestering excess Se in affected water sources
Biochar: A valuable soil amendment
Get PDFBiochar is a fine-grained, carbon enriched product created
when biomass (e.g. wood waste, manures) is bumed at relatively
low temperatures (less than 1300°F) and under an anoxic (lack of
oxygen) atmosphere. The process itself is called pyrolysis and is
similar to the production of charcoal, yet the intent is generally to
create biofuel with the concomitant production of the secondary
product, biochar.
Benefits of biochar addition to soils are recognized. Arnazonian
dark earth soils, also known as terra preta, are charcoalenriched
soils containing a high nutrient content from reduced leaching,
likely a response of human-induced biochar accumulation.
These soils, dating to between 450 BC and 950 AD, are unique to the Amazon region, as most tropical
soils are highly weathered and thus
generally infertile
Changes in soil test phosphorus and phosphorus in runoff from calcareous soils receiving manure, compost, and fertilizer application with and without alum
Get PDFIntensification of the dairy industry in southern Idaho has led
to the overapplication of manures and a buildup of soil phosphorus (P),
which is a potential threat to water quality in the region. As the use of
alum has been shown to reduce both soluble manure P and runoff P from
alum-treated manures, the objective of this study was to determine if
surface applications of alum to dairy manure and compost before soil
incorporation would reduce P losses under furrow irrigation on a calcareous
soil. The effects of manure, compost, and fertilizer application
with and without alum treatment on soil P, runoff P, and aluminum under
furrow irrigation, crop yield, tissue P concentrations, and P removal
during a 4-year period were investigated in Kimberly, Idaho, on a
Portneuf silt loam (coarse-silty, mixed superactive, mesic Durinodic
Xeric Haplocalcids). Fertilizer and manure addition had the greatest
potential to increase soluble P in soils compared with compost, which
translated to greater soluble P losses with irrigation in some instances.
The addition of alum to manure did not have any effect on soil extractable
P or soluble P losses from furrow irrigation and therefore,
when surface applied to manure before incorporation, is not a good best
management practice for stabilizing P in manure-treated calcareous soils
Changes in soil test phosphorus and phosphorus in runoff from calcareous soils receiving manure, compost, and fertilizer application with and without alum
Get PDFIntensification of the dairy industry in southern Idaho had led to the over-application of manures and a buildup of soil phosphorus (P) which is a potential threat to water quality in the region. As the use of alum has been shown to reduce both soluble manure P and runoff P from alum treated manures, the objective of this study was to determine if surface applications of alum to dairy manure and compost prior to soil incorporation would reduce P losses under furrow irrigation on a calcareous soil. The effects of manure, compost, and fertilizer application with and without alum treatment on soil P, runoff P and aluminum (Al) under furrow irrigation, crop yield, tissue P concentrations and P removal over a four year period were investigated in Kimberly, ID, on a Portneuf silt loam (coarse-silty, mixed superactive, mesic Durinodic Xeric Haplocalcids). Fertilizer and manure addition had the greatest potential to increase soluble P in soils, compared to compost, which translated to greater soluble P losses with irrigation in some instances. The addition of alum to manure did not have any effect on soil extractable P or soluble P losses from furrow irrigation, and therefore is not a good best management practice for stabilizing P in manure treated calcareous soils
Soil genesis and development, lesson 1: Rocks, minerals, and soils
Get PDFMost soil parent materials were rocks at some
time in their history. The minerals in rocks may contribute
to soil fertility and other soil properties long after the
original rock is gone. Consequently, it is a valuable skill to
be able to identify broad categories of rock. This lesson will
discuss igneous, metamorphic, and sedimentary rocks and
the minerals found in them. The lesson will also provide
opportunities for students to identify rocks based on given
characteristics.
At the completion of this lesson, students will be able to do
the following:
1. Classify rocks based on visual characteristics according
to the major types: igneous, metamorphic, and
sedimentary.
2. Predict the influence of “parent” rock on soil properties.
The lesson uses an interactive approach, embedding questions
in each section of the lesson. The lesson is written
to target educational needs of lower-level undergraduate
students and is open for use by the public and educational
institutions
Measurement of atmospheric ammonia, methane, and nitrous oxide at a concentrated dairy production facility in Southern Idaho using open-path FTIR spectrometry
Get PDFThe number of dairy cows in Idaho has increased by approximately 80% in the last decade, with the majority of
these facilities located in southern Idaho, causing air quality concerns in this region. To determine the potential air quality
impacts of these facilities, we measured ammonia (NH3), methane (CH4), and nitrous oxide (N2O) concentrations over the
pens, wastewater storage pond, and composting area on a 700‐cow open‐lot dairy using open‐path Fourier transform infrared
spectrometry (OP/FTIR). Concentrations were measured for one or two days at each location during January, March, June,
and September. Median NH3 concentrations over the pens, storage pond, and composting area ranged from 0.14 to 0.39 ppmv,
0.04 to 0.17 ppmv, and 0.06 to 0.22 ppmv, respectively, with concentrations tending to be lower in January. Average CH4
concentrations over the pens, storage pond, and composting area ranged from 2.07 to 2.80 ppmv, 1.87 to 2.15 ppmv, and 1.71
to 1.76 ppmv, respectively. Average N2O concentrations ranged from 0.31 to 0.33 ppmv for all areas, which was similar to
global background N2O concentrations. Combined ammonia emissions for the pen and storage pond areas, calculated with
a backward Lagrangian stochastic inverse‐dispersion technique, were 0.04, 0.25, 0.19, and 0.15 kg NH3 cow-1 d-1 for
January, March, June, and September, respectively, and methane emissions were 0.34, 0.55, 0.21, and 0.20 kg CH4 cow-1 d-1
for the same months. Assuming this limited monitoring was representative of the entire year, annual emissions from the pens
and storage pond were 57 kg NH3 cow-1 and 120 kg CH4 cow-1. These emission rates were similar to the limited number of
comparable studies that have been published. However, more extensive monitoring is needed to better quantify variations in
emissions throughout the year and among locations