This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
233
Transportation of poultry litter out of nutrient limited watersheds such as the Illinois River basin (eastern Oklahoma) is a logical solution for minimizing phosphorus (P) losses from soils to surface waters. Transportation costs are based on mass of load and distance transported. Th is study investigated an alternative litter storage technique designed to promote carbon (C) degradation, thereby concentrating nutrients for the purpose of decreasing transportation costs through decreased mass. Poultry litter was stored in 0.90-Mg conical piles under semipermeable tarps and adjusted to 40% moisture content, tested with and without addition of alum (aluminum sulfate). An additional study was conducted using 3.6-Mg piles under the same conditions, except tested with and without use of aeration pipes. Samples were analyzed before and after (8 wk) storage. Litter mass degradation (i.e., loss in mass due to organic matter decomposition) was estimated on the basis of changes in litter total P contents. Additional characterization included pH, total nutrients, moisture content, total C, and degree of humifi cation. Litter storage signifi cantly decreased litter mass (16 to 27%), concentrated nutrients such as P and potassium (K) and increased proportion of fulvic and humic acids. Th e addition of aeration pipes increased mass degradation relative to piles without aeration pipes. Nitrogen volatilization losses were minimized with alum additions. Increases in P and K concentrations resulted in greater monetary value per unit mass compared with fresh litter. Such increases translate to increased litter shipping distance and cost savings of $17.2 million over 25 yr for litter movement out of eastern Oklahoma.
Alternative Poultry Litter Storage for Improved Transportation and Use
as a Soil Amendment
Chad J. Penn,* Jeff ery Vitale, Scott Fine, Joshua Payne, Jason G. Warren, Hailin Zhang, Margaret Eastman, and Sheri L. Herron
The poultry industry is economically important in east-
ern Oklahoma, serving as a major source of employment in
rural areas and often as a more profi table alternative to traditional
agricultural enterprises in the region. Approximately 48.2 million
birds (USDA–NASS, 2007) were produced in Oklahoma during
2007 (USDA–NASS, 2007). Poultry feeding operations are sup-
ported by the import of animal feed containing nutrients such as
nitrogen (N), phosphorus (P), and potassium (K); these nutrients
are then exported from the farm in the form of agricultural prod-
ucts (meat, eggs, etc.). However, much of the nutrients imported
with the feed will remain on the farm in the form of manure
(Nord and Lanyon, 2003; Slaton et al., 2004), which is termed
litter when mixed with bedding used in the poultry production
house. Manure management remains an ongoing challenge to the
industry as a result of this on-farm nutrient accumulation.
Poultry litter is typically land applied to pasture or crop land,
being a good source of N, P, K, and micronutrients (McGrath et
al., 2010). Historically, litter was applied to supply plant available
N (PAN) which results in an overapplication of P relative to plant
needs (Reddy et al., 2008; Eghball and Power, 1999). Continuous
application of poultry litter to plants at PAN rates has been shown
to cause an increase in soil test P (STP) beyond agronomic opti-
mum (Sistani et al., 2004; Maguire et al., 2008). For Oklahoma,
this optimum is 32.5 mg kg−1 Mehlich-3 P (M3-P). One conse-
quence of increased STP is a greater potential for nonpoint trans-
port of P to surface water bodies through overland fl ow (Johnson
et al., 2004; Daniel et al., 1994). Input of P into surface waters
can cause eutrophication (Williams et al., 1999; Boesch et al.,
2001). Eutrophication is characterized by excess plant growth and
oxygen depletion in water and can result in algal blooms, taste
and odor problems, and fi sh kills. Th is not only reduces attractive-
ness for recreation but creates water quality concerns for drinking
water supplies.
Th e link between STP and increased potential transport of P to
surface waters has led to regulations regarding the land application
of animal wastes such as poultry litter. In Oklahoma, for example,
soils within “nutrient limited watersheds” (such as the Illinois River
basin) possessing M3-P values >150 mg kg−1 are not permitted to
of P in the soil and soilP is the upper limit on soil P levels.
Optimum soil test P concentration for agronomic production
in Oklahoma is 32.5 mg kg−1 (M3-P soil extraction; Mehlich,
1984). For P demand and crop production, it was assumed
that no P would leave the farms receiving litter; this provided
a “worst-case scenario” for moving litter. Th e increase in soil
test P with litter applications was estimated using relationships
developed for Oklahoma soils (Davis et al., 2005).
Economic benefi ts were determined by the cost savings in
applying equivalent nutrient levels from poultry litter versus
commercial fertilizer sources according to the following equation:
NPK NPKBENEFITS PRCijt ijti j t
Q X= Φ∑∑∑ [5]
where ΦNPK
is the transformation coeffi cient governing the
content of NPK per unit of litter, and PRCNPK
is the vector of
N, P, and K prices. Th is valuing approach also enabled a direct
comparison between conventional and degraded poultry litter.
Poultry litter demand was estimated based on its use as a sub-
stitute for N, P, and K from commercial fertilizer. Poultry litter
applications were applied in the model on the basis of observed
crop and hay acreage at the county level (USDA–NASS, 2009)
and achievement of 32.5 mg kg−1 M3-P, which established an
aggregate demand for P. Current average soil P levels were esti-
mated using soil test samples from Oklahoma State University’s
Soil Testing Laboratory, which contains records of 65,000 soil
samples. Consistent with Carreira et al. (2007), poultry litter was
valued using commercial fertilizer prices to establish nutrient
prices for N, P, and K (Oklahoma State University NPK, 2010).
Table 1 was then used to value poultry litter on a weight basis
(i.e., the estimate of ΦNPK
) based on the measured concentrations
of N, P, and K in the poultry litter. Transportation, handling,
and fi eld application costs used in the economic model (Eq. [3])
were obtained from Carreira et al. (2007), with values of Cij =
$0.10 Mg−1 km−1, Hij = $18.73 Mg−1, and A
ij = $ 7.72 Mg−1.
Th e transportation model was solved by maximizing the
diff erence between the BENEFITS and COSTS equations
subject to maintaining soil P levels within the prescribed limits
dictated by Eq. [3]. Th e General Algebraic Modeling Systems
(GAMS) software package was used to fi nd the optimal solu-
tions to the transportation modeling formulation given by Eq.
[2–5]. Results were then linked to the Arc-Maps GIS system
(GIS Arcview, ESRI, Redlands, CA) where maps were created
to present results of the transportation fl ows.
Statistical AnalysisTh e small-scale litter storage study was a randomized complete
block design, with year as the blocking factor (3 yr) and two
diff erent treatments; normal litter and alum-amended litter.
Th e large-scale litter study was a complete randomized design
with two diff erent treatments: no aeration and passive aeration.
For both studies, ANOVA was conducted to determine if there
were signifi cant diff erences among chemical properties (p =
0.05) between the fresh litter (Day 0) and degraded litter (Day
60). Th e statistical procedure was conducted with SAS software
(SAS Institute, 2003) using the PROC GLM command.
Results and DiscussionTh e broiler litter collected each year of the study were typical in
pH, dry matter content, total C, N, and P, and WSP (see “pre-
Table 1. Percentage mass reduction and litter characteristics (dry weight basis) before and after initiating the degradation storage process both with and without the addition of aluminum sulfate.
Litter treatment DM† % mass reduction‡ pH TC§ TN§ NH4
NO3
WSP§ HI¶
——————————————— g g−1 ——————————————— ———————— mg kg−1 ————————
cessfully resulted in a signifi cant decrease in dry matter for
both normal and alum-treated litter; percentage mass reduc-
tion ranged from 18.1 to 26.9 (Table 1). Clearly, the dry matter
reduction can be attributed mostly to organic C decomposition
(Table 1) and subsequent loss as CO2 gas, with some reduction
resulting from N volatilization. Th is caused an average mass
reduction of 19.6 and 23% for normal litter and alum-treated
litter, respectively (Table 1). If we consider the decrease in litter
mass, then the C reduction expressed as a percentage
of the pre-degraded litter C content would be 32.7
and 33.2% for normal and alum-treated litter, respec-
tively. Warren et al. (2008) also found similar results
for normal and alum amended (10% dry weight)
poultry litter that was incubated in cups (0.30 g g−1
moisture adjusted, 25°C) for 93 d in a laboratory.
After 63 d, the authors found that 16 and 29% of the
litter dry matter had been lost from normal and alum-
amended litter, respectively.
Th e increased dry matter loss from alum-amended
litter may be an indirect eff ect of pH. Initially, a
10% alum application rate to litter is expected to
decrease pH 1 to 3 units, resulting in a pH of about
4 to 6 (Moore et al., 1999; Moore and Miller, 1994).
Although the pH of alum-amended litter tends to
increase after several weeks of equilibration, the fi nal
pH of alum-amended litter will still be signifi cantly
lower than normal litter (Table 1). Th e lower pH of
the alum-amended litter is probably having an impact
on litter microbial populations, which in turn is
causing diff erences in carbon degradation/utilization
among the litter treatments. For example, Cook et al.
(2008) showed that alum additions to poultry litter
shifted the microbial populations from mostly bacte-
rial to fungi. Since fungi are more eff ective at utiliz-
ing lignin-based carbon sources compared to bacteria
(Paul and Clark, 1996), this could have an impact
on the decomposition of litter components such as
rice hulls and wood chips and would also explain the
observed increases in litter degradation (i.e., mass reduction)
for this study.
Although the fi nal total N concentrations in the degraded
litter were similar to pre-degraded litter (Table 1), this equates
to 26 and 16% total N losses from the degraded normal and
alum-amended litter, respectively, when the mass reduction
is considered. Presumably, the loss of N was due to ammonia
(NH3) volatilization since leaching of water and surface runoff
was not possible as the piles were covered and kept under a
roof. Various studies have shown that composting litter results
in appreciable losses of N (Henry and White, 1993; Hansen et
al., 1989; Kithome et al., 1999). DeLaune et al. (2004) found
that composting litter lost 42 to 44% of initial total N via NH3
volatilization when litter was windrowed and turned weekly
Table 2. Impact of aeration on the litter degradation storage process. Average percent mass reduction and litter characteristics are presented on a dry weight basis before and after initiating the degradation storage process.
Litter treatment DM† % mass reduction‡ pH TC§ TN§ NH4
‡ Percentage of the initial litter mass that was degraded; calculated based on changes in concentration of a nongaseous and recoverable element
(phosphorus) after degradation.
§ TC, total carbon; TN, total nitrogen; WSP, water soluble phosphorus.
¶ Least signifi cant diff erence at P = 0.05; ns, not signifi cant.
Fig. 1. Average total phosphorus and potassium concentrations before and after the degradation storage process among normal and alum treated litter. ** indicates signifi cant diff erences between fresh and degraded litter at P = 0.01.
for 92 d. Th e N loss values for the current study are lower
than those reported for traditional composting presumably
because litter piles were covered with semipermeable materials
and turned only once, thereby slowing the loss of NH3 gas.
As expected, the alum-amended litter reduced N losses during
degradation relative to normal litter due to acidifi cation of the
litter, thereby preventing NH4 deprotontation and subsequent
NH3 gas formation (Moore et al., 1996).
Due to the concentrating eff ect of the mass reduction (i.e.,
C degradation), there is an accompanying increase in the con-
centration of nonvolatile nutrients (Warren et al., 2008; Tiquia
and Tam, 2002). An example of this concentrating eff ect is
shown in Fig. 1 for P and K. Warren et al. (2008) also showed
that litter amended with moisture followed by 63 d of labora-
tory incubation increased total P from 17,500 to 23,600 mg
kg−1. For their study, this 34% increase in total P concentration
corresponded well with their measured decrease in litter mass.
Although litter moisture content was initially adjusted
to 0.40 g g−1 for the storage process, there was no diff erence
in fi nal dry matter content after 8 wk of degradation com-
pared with the fresh pre-degraded litter (Table 1). In addition
to a greater concentration of total nutrients, the degraded
normal litter also possessed a signifi cantly higher concen-
tration of WSP compared with the fresh pre-degraded litter
(Table 1), suggesting that the former may better serve as a
plant nutrient source. However, alum-treated litter did not
release soluble P during degradation; in fact, alum-treated
litter possessed lower WSP concentrations compared with
fresh litter (Table 1). Application of alum to litter has clearly
been shown to reduce soluble P concentrations by adsorbing
phosphate onto newly formed amorphous Al oxides/hydrox-
ides and precipitation of Al phosphate mineral (Peak et al.,
2002). In addition, alum amendments to litter will also pre-
vent the mineralization of phytic acid due to the formation of
Al-phytate (Warren et al., 2008).
With degradation of litter C, there was also a shift in the C
fractions as evidenced by the HI; a lower HI value indicates a
more “humifi ed” or degraded material (Table 1). Essentially,
the degraded litter possessed a greater concentration of HA
plus FA and less non-humic C compared with the fresh pre-
degraded litter, causing a decrease in the HI (Table 1). Petrussi
et al. (1988) also showed a decrease in the HI for swine, cattle,
and sheep manure after composting with earthworms. Among
composting lignin-cellulostic wastes, the degree of humifi ca-
tion was found to be a good indicator of compost maturity as
organic materials further degraded with time (Mondini et al.,
2006). Th e degraded litter in our study possessed a HI simi-
lar to urban compost (Ciavatta et al., 1990; Gigliotti et al.,
1999). Th e greater degree of humifi cation in the degraded litter
compared with fresh pre-degraded litter was also somewhat
evident by the lack of malodors and darker color of degraded
litter. Although not statistically signifi cant, the NMR analysis
suggested that the degraded litter possessed a higher ratio of
alkyl:o-alkyl groups compared with pre-degraded fresh litter
(0.31 vs. 0.26, ± 0.09) and a higher degree of aromaticity (ratio
of aromatic to nonaromatic functional groups; 0.22 vs. 0.20,
± 0.06). An increased ratio of alkyl:o-alkyl and aromaticity
indicates a greater degree of humifi cation (Inbar et al., 1990;
Simpson et al., 2008).
Th e application of more humifi ed organic materials to soils
may provide additional benefi ts, including enhanced soil qual-
ity. For example, Fernandez et al. (2007) applied composted
sewage sludge to a sandy loam for 3 yr and found that com-
posted sludge increase soil humic acid percentage and degree
of polymerization compared with a thermally dried sludge and
chemical fertilizer treatment.
Large-Scale Litter Storage Piles
and the Eff ect of AerationInternal pile temperatures ranged from 40 to 55°C during
the storage test period, thereby achieving thermophilic tem-
peratures (>40°C). Th e large-scale litter storage piles resulted
in mass degradation similar to the 0.9-Mg litter storage piles
(Tables 1 and 2) and laboratory-incubated litter after 63 d
(Warren et al., 2008). However, the addition of passive aeration
via perforated pipe network within the pile caused a signifi cant
increase in mass reduction compared with piles without aera-
tion pipes (Table 2; 8.1% point increase in mass reduction rela-
tive to nonaerated piles). Again, this mass reduction occurring
from C degradation resulted in an increase in concentration of
nonvolatile nutrients such as P (Table 2). Similar to the small-
scale piles the degraded litter contained lower total C, total N,
NH4, and NO
3 compared with fresh pre-degraded litter. Water
soluble P also increased for the degraded litters, although this
was not statistically signifi cant (Table 2).
Th e piles aerated through use of the perforated pipe signifi -
cantly increased percentage mass reduction due to the ability to
provide more oxygen to microorganisms that oxidize organic C
(Lau et al., 1992; Leton et al., 1983). Among composting facil-
ities, aeration has been shown to decrease the active decompo-
sition time (Sartaj et al., 1997; Finstein et al., 1980). Aeration
helps to produce an odorless end product, high temperatures
required for the inactivation of pathogens and weeds, and
remove waste gases, excess heat, and moisture (Rynk, 1992;
Leton and Stentiford, 1990).
Poultry Litter TransportationEqual dry matter contents of degraded and fresh poultry
litter, plus an increase in total P and K concentrations with
only a small decrease in total N concentrations, resulted in a
degraded litter with a greater economic value than conven-
tional litter. Phosphorus and K can be transported at lower
costs when shipped as degraded litter rather than conven-
tional fresh litter. On a standard truck unit carrying 21.7 Mg
of litter (70% dry matter), degraded litter would be able to
deliver 337 kg of P, signifi cantly more than the 266 kg deliv-
ered by nondegraded litter, assuming P concentrations deter-
mined in the small-scale study (Fig. 1). Based on a typical
shipping distance of 80 km, degraded litter would increase
economic benefi ts by $180.96 per haul due to higher nutri-
ent concentration. Th ere would also be a substantial increase
in the break-even distance over which litter could be prof-
itably transported. Degraded litter could be transported up
to 416 km, 82 km further than conventional litter’s break-
even distance of 334 km, based on current N, P, and K values
(Oklahoma State University NPK, 2010).
Penn et al.: Alternative Poultry Litter Storage 239
Degraded litter would also result in more effi cient and eff ec-
tive movement of P out of nutrient limited watersheds. Results
of the PLTM (developed from results of the small-scale litter
study; Fig. 1) indicate the optimal allocation of Oklahoma’s
annual production of 149,659 Mg of poultry litter over a 25-yr
period (Fig. 2). Within the fi rst 6 yr, the seven major poultry-
producing counties in the Illinois River watershed would have
produced and applied enough P on their soils to meet agro-
nomic P requirements within their respective county. Once
this occurs, those major producing counties will need to export
poultry litter to counties further west. Because of lower trans-
portation costs and a greater break-even shipping distance,
degraded litter would have a larger market area and would sat-
isfy a larger proportion of P demand than conventional litter
(Fig. 2). After 10 yr, the PLTM projects that degraded litter
would be able to access producers in 10 additional counties
compared with conventional litter (Fig. 2). Th e most signifi -
cant eff ect of degraded litter appears after 20 yr. At this time,
conventional litter would reach its break-even distance at
which further hauling would cost more than the litter nutrient
value and shipping poultry litter would therefore no longer be
profi table. However, degraded litter would remain economi-
cally viable for the next 25 yr. As a result, an additional seven
counties would be supplied with poultry litter. (Fig. 2).
Fig. 2. Results of the poultry litter transportation model illustrating (a) poultry litter demand, (b) annual supply, and potential transport of (c, e) fresh litter and (d, f) degraded litter 10 and 25 yr in the future.
Poultry litter would generate economically important ben-
efi ts over the next 20 to 25 yr (Table 3). Degraded poultry
litter would provide the largest impact, reaching $66.4 mil-
lion over a 25-yr period. Th at impact is generated by shipping
3.67 million Mg of poultry litter over an average distance
of 200 km. Conventional litter would generate an economic
impact of $49.2 million, $17.2 million less than degraded
litter, and corresponding to a diff erence of 34.9% compared
with degraded litter (Table 3). Conventional litter off ers less
economic potential than degraded litter since it is more costly
to ship, ultimately limiting its ability to reach wayward points
to the west. Over its 20 yr economic life, conventional litter
would ship 3.06 million Mg of poultry litter, 19.8% less than
degraded litter.
ConclusionsAlthough the alum-amended litter displayed a mass reduction
up to 26.9% due to carbon degradation, when the mass of the
aluminum sulfate added to the litter is taken into account, the
net mass reduction is only 15.3%. Th is makes the normal litter
storage (i.e., without alum) process more effi cient in net mass
reduction compared with alum-amended litter. In addition,
the cost of alum should be considered, approximately $343
Mg−1, not including shipping (Rex Johns, General Chemical,
personal communication, 2010).
Th e proposed technique for litter degradation, with or
without the use of aeration pipes, has distinct advantages over
traditional composting processes in the context of litter trans-
port. Th e simplifi ed system requires much less time, labor, and
cost compared with traditional composting in that litter does
not need to be turned on a weekly basis and N losses are mini-
mized. Overall, the process simply involves addition of mois-
ture (target of 0.40 g g−1) to litter while moving it into a conical
shaped pile (with or without a network of perforated pipes),
covering with a polyethylene tarp, and if aeration pipes are not
utilized, optionally turning the litter once after 30 d and re-
covering, allowing for 30 more days of degradation.
ReferencesAdeli, A., H. Tewolde, K.R. Sistani, and D.E. Rowe. 2009. Broiler litter
fertilization and cropping system impacts on soil properties. Agron. J. 101:1304–1310.
Boesch, D.F., R.B. Brinsfi eld, and R.E. Magnien. 2001. Chesapeake Bay eu-trophication: Scientifi c understanding, ecosystem restoration, and chal-lenges for agriculture. J. Environ. Qual. 30:303–320.
Britton, J., and G.L. Bullard. 1998. Summary of poultry litter samples in Oklahoma. Fact Sheet CR-8214. Oklahoma Cooperative Extension, Stillwater.
Carreira, R., K. Young, H. Goodwin, and E. Wailes. 2007. How far can poultry litter go? A New technology for litter t. J. Agric. Appl. Econ.
39:611–623.
Ciavatta, C., M. Govi, L. Vittori Antisari, and P. Sequi. 1990. Characterization of humifi ed compounds by extraction and fractionation on solid polyvi-nylpyrrolidone. J. Chromatogr. A 509:141–146.
Collins, A.R., and T. Basden. 2006. A policy evaluation of transport subsidies for poultry litter in West Virginia. Rev. Agric. Econ. 28:72–88.
Cook, K.L., M.J. Rothrock, J.G. Warren, K.R. Sistani, and P.A. Moore. 2008. Eff ect of alum treatment on the concentration of total and ureolytic mi-croorganisms in poultry litter. J. Environ. Qual. 37:2360–2367.
Daniel, T.C., A.N. Sharpley, D.R. Edwards, R. Wedepohl, and J.L. Lemun-yon. 1994. Minimizing surface water eutrophication from agriculture by phosphorus management. J. Soil Water Conserv. 49:30–38.
Davis, R.L., H. Zhang, J.L. Schroder, J.J. Wang, M.E. Payton, and A. Zazulak. 2005. Soil characteristics and phosphorus level eff ect on phosphorus loss in runoff . J. Environ. Qual. 34:1640–1650.
DeLaune, P.B., P.A. Moore, Jr., T.C. Daniel, and J.L. Lemunyon. 2004. Eff ect of chemical and microbial amendments on ammonia volatilization from composting poultry litter. J. Environ. Qual. 33:728–734.
Eghball, B., and J.F. Power. 1999. Phosphorus- and nitrogen-based manure and compost applications: Corn production and soil phosphorus. Soil Sci. Soc. Am. J. 63:895–901.
Eghball, B., J.F. Power, J.E. Gilley, and J.W. Doran. 1997. Nutrient, carbon, and mass loss during composting of beef cattle feedlot manure. J. Envi-ron. Qual. 26:189–193.
Fernandez, J.M., D. Hernandez, C. Plaza, and A. Polo. 2007. Organic matter in degraded agricultural soils amended with composted and thermally dried sewage sludges. Sci. Total Environ. 378:75–80.
Finstein, M.S., J. Cirello, S.T. MacGregor, F.C. Miller, D.J. Suler, and P.F. Strom. 1980. Engineering principles of sludge composting. J. Water Pol-lut. Control Fed. 52:2037–2040.
Gigliotti, G., D. Businelli, and P.L. Giusquiani. 1999. Composition changes of soil humus after massive application of urban waste compost: A com-parison between FT-IR spectroscopy and humifi cation parameters. Nutr. Cycling Agroecosyst. 55:23–28.
Hansen, R.C., H.M. Keener, and H.A.J. Hoitink. 1989. Poultry manure com-posting: An exploratory study. Trans. ASAE 36:2151–2157.
Henry, S.T., and R.K. White. 1993. Composting broiler litter from two man-agement systems. Trans. ASAE 26:873–877.
Inbar, Y., Y. Chen, and Y. Hadar. 1990. Humic substances formed during the composting of organic matter. Soil Sci. Soc. Am. J. 54:1316–1323.
Johnson, A.F., D.M. Vietor, F.M. Rouquette, Jr., and V.A. Haby. 2004. Fate of phosphorus in dairy wastewater and poultry litter applied on grassland. J. Environ. Qual. 33:735–739.
Kaiser, D.E., A.P. Mallarino, M.U. Haq, and B.L. Allen. 2009. Runoff phos-phorus loss immediately after poultry manure application as infl uenced by application rate and tillage. J. Environ. Qual. 38:299–308.
Kithome, M., J.W. Paul, and A.A. Bomke. 1999. Reducing nitrogen losses during simulated composting of poultry manure using adsorbents or chemical amendments. J. Environ. Qual. 28:194–201.
Lau, A.K., K.V. Lo, P.H. Liao, and J.C. Yu. 1992. Aeration experiments for swine waste composting. Bioresour. Technol. 41:145–152.
Leton, T.G., and E.I. Stentiford. 1990. Control of aeration in static pile com-posting. Waste Manag. Res. 8:299–306.
Leton, T.G., E.I. Stentiford, D.D. Mara, and P.L. Taylor. 1983. Temperature and oxygen control of refuse/sludge aerated static pile systems. In E.I. Stentiford (ed.) Composting of solid wastes and slurries. Leeds University, Leeds, UK.
Leytem, A.B., and K. Kpomblekou-A. 2009. Total phosphorus in soil. p. 44–50. In J.L. Kovar and G.M. Pierzynski (ed.) Methods of phosphorus analysis for soils, sediments, residuals, and waters. Southern Cooperative Series Bull. 408. Available at http://www.sera17.ext.vt.edu/SERA_17_Publications.htm (verifi ed 30 Nov. 2010).
Table 3. Potential litter transport and economic benefi ts of fresh and degraded litter relative to commercial fertilizer as determined by the Poultry Litter Transportation Model.
yr —————————— Mg —————————— —————————— $ million ——————————
5 730,149 730,149 0 21.9 27.3 24.7
10 1,460,210 1,460,210 0 36.4 44.8 23.5
15 2,190,314 2,190,314 0 44.0 55.9 27.0
20 2,920,418 2,920,418 0 47.7 63.0 32.1
25 3,047,347 3,650,523 19.2 49.2 66.4 35.1
Penn et al.: Alternative Poultry Litter Storage 241
Maguire, R.O., G.L. Mullins, and M. Brosius. 2008. Evaluating long-term ni-trogen- versus phosphorus-based nutrient management of poultry litter. J. Environ. Qual. 37:1810–1816.
Mao, J.D., W.G. Hu, K. Schmidt-Rohr, G. Davies, E.A. Ghabbour, and B. Xing. 2000. Quantitative characterization of humic substances by solid-state nuclear magnetic resonance. Soil Sci. Soc. Am. J. 64:873–884.
McGrath, S., R.O. Maguire, B.F. Tracy, and J.H. Fike. 2010. Improving soil nutrition with poultry litter application in low-input forage systems. Agron. J. 102:48–54.
Mehlich, A. 1984. Mehlich 3 soil extractant: A modifi cation of Mehlich 2 extractant. Commun. Soil Sci. Plant Anal. 15:1409–1416.
Mondini, C., M.A. Sanchez-Monedero, T. Sinicco, and L. Leita. 2006. Evaluation of extracted organic carbon and microbial biomass as sta-bility parameters in ligno-cellulosic waste composts. J. Environ. Qual. 35:2313–2320.
Moore, P.A., Jr., T.C. Daniel, D.R. Edwards, and D.M. Miller. 1996. Evalu-ation of chemical amendments to reduce ammonia volatilization from poultry litter. Poult. Sci. 75:315–320.
Moore, P.A., Jr., T.C. Daniel, and D.R. Edwards. 1999. Reducing phospho-rus runoff and improving poultry production with alum. Poult. Sci. 78:603–698.
Moore, P.A., Jr., and D.M. Miller. 1994. Decreasing phosphorus solubility in poultry litter with aluminum, calcium, and iron amendments. J. Envi-ron. Qual. 23:325–330.
Nelson, D.W., and L.E. Sommers. 1996. Total carbon, organic carbon, and organic matter. In D.L. Sparks (ed.) Methods of soil analysis. Part 3. Chemical methods. SSSA Book Ser. 5. SSSA and ASA, Madison, WI.
Nord, E.A., and L.E. Lanyon. 2003. Managing material transfer and nutrient fl ow in an agricultural watershed. J. Environ. Qual. 32:562–570.
Oklahoma State University NPK. 2010. Current fertilizer prices in central OK. Available at http://www.npk.okstate.edu/ (verifi ed 30 Nov. 2010).
Paudel, K.P., M. Adhikari, and N.R. Martin. 2004. Evaluation of broiler litter transportation in northern Alabama, USA. J. Environ. Manage. 73:15–23.
Paul, E.A., and F.E. Clark. 1996. Soil microbiology and biochemistry. 2nd ed. Academic Press, San Diego, CA.
Payne, J.B., and M.D. Smolen. 2006. Oklahoma’s poultry litter market. p. 32–35. In 2006 National Poultry Waste Management Symposium Proc., Springdale, AR. [CD] 23–25 Oct. 2006.
Peak, D., J.T. Sims, and D.L. Sparks. 2002. Solid-state speciation of natural and alum-amended poultry litter using XANES spectroscopy. Environ. Sci. Technol. 36:4253–4261.
Petrussi, F., M. De Nobili, M. Viotto, and P. Sequi. 1988. Characterization of organic matter form animal manures after digestion by earthworms.
Plant Soil 105:41–46.
Reddy, K.C., S.S. Reddy, R.K. Malik, J.L. Lemunyon, and D.W. Reeves. 2008. Eff ect of fi ve-year continuous poultry litter use in cotton production on major soil nutrients. Agron. J. 100:1047–1055.
Rynk, R. 1992. On-farm composting handbook. Publ. NRAES-54. Natural Resource, Agriculture, and Engineering Service, Ithaca, NY.
Sartaj, M., L. Fernandes, and N.K. Patni. 1997. Performance of forced, pas-sive, and natural aeration methods for composting manure slurries. Trans. ASAE 40:457–463.
SAS Institute. 2003. SAS user’s guide: Statistics. SAS Inst., Cary, NC.
Silva, M.E., L.T. Lemos, A.C. Cunha-Queda, and O.C. Nunes. 2009. Co-composting of poultry manure with low quantities of carbon-rich mate-rials. Waste Manag. Res. 27:119–128.
Simpson, M.J., A. Otto, and X. Feng. 2008. Comparison of solid-state carbon-13 nuclear magnetic resonance and organic matter biomark-ers for assessing soil organic matter degradation. Soil Sci. Soc. Am. J. 72:268–276.
Sistani, K.R., G.E. Brink, A. Adeli, H. Tewolde, and D.E. Rowe. 2004. Year-round soil nutrient dynamics from broiler litter application to three ber-mudagrass cultivars. Agron. J. 96:525–530.
Slaton, N.A., K.R. Brye, M.B. Daniels, T.C. Daniel, R.J. Norman, and D.M. Miller. 2004. Nutrient input and removal trends for agricultural soils in nine geographic regions in Arkansas. J. Environ. Qual. 33:1606–1615.
Tiquia, S.M., and N.F.Y. Tam. 2002. Characterization and composting of poultry litter in forced-aeration piles. Proc. Biochem. 37:869–880.
USDA–NASS. 2007. Oklahoma poultry production data. Available at http://www.nass.usda.gov/index.asp (verifi ed 30 Nov. 2010). USDA National Agricultural Statistics Services, Washington, DC.
USDA–NASS. 2009. Oklahoma crop production data. Available at http://www.nass.usda.gov/index.asp (verifi ed 30 Nov. 2010). USDA National Agricultural Statistics Services, Washington, DC.
USDA–NRCS. 2007. Natural Resources Conservation Service conservation practice standard, nutrient management (acre) Code 590. Available at http://efotg.nrcs.usda.gov/references/public/OK/590std_307.pdf (veri-fi ed 30 Nov. 2010).
Van Horn, H.H., G.L. Newton, and W.E. Kunkle. 1996. Ruminant nutrition from an environmental perspective: Factors aff ecting whole-farm nutri-ent balance. J. Anim. Sci. 74:3082–3102.
Warren, J.G., C.J. Penn, J.M. McGrath, and K. Sistani. 2008. Th e impact of alum additions on organic P transformations in poultry litter and soils receiving alum-treated poultry litter. J. Environ. Qual. 37:469–476.
Williams, C.M., J.C. Barker, and J.T. Sims. 1999. Management and utilization of poultry wastes. Rev. Environ. Contam. Toxicol. 162:105–157.