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Water treatment residuals and biosolids long-term co-applications effects to semi-arid grassland soils and vegetation
Get PDFWater treatment residuals (WTRs) and biosolids are byproducts from municipal water treatment
processes. Both byproducts have been studied separately for land application benefits. There
are possible environmental benefits of WTRs and biosolids co-application but these studies
are limited. Our objectives were to determine relative long-term (13–15 yr) effects of a single
and short-term (2–4 yr) effects of repeated WTR-biosolids co-applications on soil chemistry,
microbiology, and plant community structure in a Colorado semiarid grassland. Only relative
changes associated between co-applications were studied, as we assumed WTR application would
only occur if used as a management practice. Three WTR rates (5, 10, and 21 Mg ha–1) were surface
co-applied (no incorporation) with a single biosolids rate (10 Mg ha–1) once in 1991 (long-term
plots) and again in 2002 (short-term plots). Soil 0- to 8-, 8- to 15-, and 15- to 30-cm depth pH,
electrical conductivity (EC), NO3–N, NH4–N, total C, and total N were not aff ected by WTR
application in 2004, 2005, or 2006. Ammonium-bicarbonate diethylenetriaminepentaacetic
acid (AB-DTPA)- extractable soil Al was unaffected by WTR application, but extractable P and
Mo decreased with increasing WTR rate because of WTR adsorption. Plant tissue P and Mo
content decreased with specific plant species and years due to adsorption to WTR; no deficiency
symptoms were observed. Plant community composition and cover were largely unaffected by
WTR application. Soil microbial community structure was unaffected by WTR co-application
rate (total ester-linked fatty acid methyl ester [EL-FAME] concentrations ranged from 33.4 to
54.8 nmol g–1 soil), although time since biosolids-WTR application affected a subset of microbial
community fatty acids including markers for Gram-positive and Gram-negative bacteria. Overall,
WTR-biosolids co-applications did not adversely affect semiarid grassland ecosystem dynamics
Reducing sucrose loss in sugarbeet storage
Get PDFControlling sucrose loss in sugarbeet
storage has been an industry
goal since the 1950s. Sugarbeet
roots utilize sucrose for energy to
maintain themselves.
Dessication from wind and sun or
too much rain and microbial activity
can negatively influence stored roots,
increasing respiration and the buildup
of impurities.
Factors such as scalping, impacts
and wounding during harvest and
transport, mud and weeds in piles, and
unusually high and low temperature
can also lead to sucrose loss.
Disease and drought stress during
production can also predispose roots
to sucrose loss in storage.
In particular, rhizomania caused
by Beet necrotic yellow vein virus
has been shown to compromise the
storability of roots allowing for significant
sucrose losses in storage by early
December.
Sucrose losses over 90 percent have
been documented in long-term storage
(142 days) with cultivars that lack
storability. Thus, developing a cultivar
selection program for storage could be
of considerable benefit to the sugarbeet
industry
Case Study: On-Farm Evaluation of Liquid Dairy Manure Application Methods to Reduce Ammonia Losses
Get PDFThe volatilization of NH3 from landapplied manure 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 relative differences in potential NH3 losses from land application of liquid dairy manure were determined via 3 methods: surface application, Aerway incorporation (shallow incorporation with a rolling tine aerator), and subsurface injection. Liquid manure was applied at a rate of 190 m3/ha on 4 farms with average N and P application rates ranging from 28 to 130 kg N/ha and 6 to 36 kg P/ha, respectively. Average NH3 concentrations were measured with passive samplers for 3 d after manure application and ranged from 0.03 to 0.21 mg NH3-N/m3. There were main effects of sampler height, day, and application method. The greatest NH3 concentrations occurred during the first 48 h after manure application. Concentrations of NH3 measured at 1 m (averaged over 48 h) indicated that surface and Aerway applications had the greatest concentrations (0.16 and 0.17 mg NH3-N/m3, respectively) whereas subsurface injection of manure resulted in a 67% decrease in NH3 concentration, which was similar to the control plots (0.06 and 0.04 mg NH3-N/m3, respectively). Subsurface injection was the best method of liquid manure application for minimizing NH3 losses
High-yielding corn response to applied phosphorus, potassium, and sulfur in Nebraska
Get PDFNutrient management recommendations may change as yield levels and efficiency of crop production increase. Recommendations
for P, K, and S were evaluated using results from 34 irrigated corn (Zea mays L.) trials conducted in diverse situations across
Nebraska. The mean yield was 14.7 Mg ha–1 with adequate fertilizer applied. The median harvest index values were 0.52, 0.89,
0.15, and 0.56 for biomass, P, K, and S, respectively. Median grain yields were 372, 49, and 613 kg kg–1 of aboveground plant
uptake of P, K, and S, respectively. The estimated critical Bray-1 P level for corn response to 20 kg P ha–1 was 20 mg kg–1 when the
previous crop was corn compared with 10 mg kg–1 when corn followed soybean [Glycine max (L.) Merr.]. Soil test K was generally
high with only three site-years <125 mg kg–1. Over all trials, application of 40 kg K ha–1 resulted in a 0.2 Mg ha–1 mean grain
yield decrease. Application of 22 kg S ha–1 did not result in significant yield increase in any trial. Soil test results accounted for
twice as much variation in nutrient uptake when soil organic matter (SOM) and pH were considered in addition to the soil test
nutrient values. The results indicate a need to revise the current recommendation for P, to maintain the current K and S recommendations,
and to use SOM and pH in addition to soil test nutrient values in estimating applied nutrient requirements for
irrigated high yield corn production
PAM in irrigated agriculture: Processes and soil-PAM interactions influencing canal sealing
Get PDFTo identify or develop alternative polymers, which may successfully replace
polyacrylamide (PAM) as a reservoir or canal sealant, it is important to understand the
nature of the sealing processes in earthen irrigation water structures and how PAM
interacts with those processes to alter water seepage. The purpose of this paper is to
review mechanisms that influence water infiltration into unlined irrigation canals and
ponds and consider how PAM interactions with soils may alter these processes
Insecticide seed treatments for sugarbeet
Get PDFPest feeding and vectoring of viruses cause serious problems in sugarbeet production worldwide. In order to ameliorate pest and disease problems on sugarbeet, two seed treatments, Poncho Beta (60 g a.i. clothianidin + 8 g a.i. beta-cyfluthrin/100,000 seed) and Cruiser Tef (60 g a.i. thiamethoxam + 8 g a.i. tefluthrin/100,000 seed) were investigated (the neonicotinoid was tested alone in some trials). The two seed treatments and an untreated check were tested in a series of eight field trials from 2006 to 2008 along with various commercial sugarbeet cultivars in a randomized complete block design with eight replications per trial. Natural pest incidence and curly top symptoms were evaluated. Both Poncho Beta and Cruiser Tef provided significant reduction in curly top symptoms and incidence of spinach leafminer (Pegomya hyoscyami Panzer), black bean aphid (Aphis fabae Scopoli), and sugarbeet root aphid (Pemphigus betae Doane). At times Poncho Beta performed better than Cruiser Tef, but yield parameters for the two products were similar. When averaged over the trials, Poncho Beta improved yields over the untreated check by 3.3 t/A, a 9% increase. Neonicotinoid seed treatments will play an important role in disease and pest management in sugarbeet production, but should be viewed as a supplement to host resistance and not a substitute for it
Evaluation of Beta corolliflora for resistance to curly top in Idaho
Get PDFCurly top of sugarbeet is caused by Beet severe curly top
virus (BSCTV) or closely related curtovirus species which
are vectored by the beet leafhopper (Circulifer tenellus).
Beta corolliflora, shown in 1969 to impart a very high level
of curly top resistance to sugarbeet into the BC2 generation,
is a wild relative of cultivated sugarbeet that has not
been utilized in breeding programs. The nature of curly top
resistance from B. corolliflora seems to be reduced symptoms
and resistance to viral accumulation. Field screening
of 14 B. corolliflora accessions for resistance to curly top
followed by PCR detection of BSCTV did not identify any
accessions with phenotypic symptoms of curly top and 9
accessions did not have detectable virus. Clip cage inoculations
followed by PCR detection of BSCTV and of related
species, Beet mild curly top and Beet curly top viruses, were
difficult to interpret due to small sample size but indicated
that accessions BETA 408, BETA 414, BETA 528,
BETA 690, and BETA 805, from Genebank Gatersleben,
Foundation Liebniz Institute of Plant Genetics and Crop
Plant Research, Gatersleben, Germany had no visible curly
top symptoms or evidence of virus accumulation. Results
of a preference test showed that beet leafhoppers did not
have a strong aversion to B. corolliflora and likely would
have at least sampled the plants in the field. Therefore,
field screening for resistance to curly top, at least in the
early generations of an introgression program, should be
successful
Impact of removing straw from wheat and barley fields: A literature review
Get PDFThe sustainability of straw removal from wheat and barley fields from the standpoint of
its effects on soil properties and nutrient cycling is a concern. A recent literature review
reveals that there is no negative effect of small grain straw removal on soil organic carbon
(SOC) content with irrigated conditions. With rainfed conditions, the results could be
more variable and depend on site productivity. Large amounts of nutrients are removed
when straw is removed, accelerating the rate of nutrient depletion and cost of replacing
these nutrients
Clinoptilolite zeolite influence on inorganic nitrogen in silt loam and sandy agricultural soils
Get PDFDevelopment of best management practices can help improve inorganic nitrogen (N)
availability to plants and reduce nitrate-nitrogen (NO3-N) leaching in soils. This study was
conducted to determined the influence of the zeolite mineral Clinoptilolite (CL) additions on
NO3-N and ammonium-nitrogen (NH4-N) in the soil/leachate system of two common Pacific
Northwest soils (Portneuf silt loam and Wolverine sand)
Soil genesis and development, lesson 2: Weathering processes of rocks and minerals
Get PDFWeathering of rocks and minerals, which include
physical, chemical, and biological processes, contributes to
the development of soil. The degree of weathering depends
not only on the rock and mineral composition but also
on climate and biological activities. Experiential learning
activities for different global regions support the learning
objectives.
At the completion of this lesson, students will be able to do
the following:
1. Describe how climatic factors influence the weathering
of rocks and minerals.
2. Define and distinguish physical, chemical, and biological
weathering processes.
The lesson is written to target educational needs of lower-level
undergraduate students in earth and environmental
sciences and is available for use by the public and educational
institutions