manure and nitrogen fertilizer effects on corn productivity and soil fertility under drip and furrow...

This article was downloaded by: [134.117.10.200]On: 30 November 2014, At: 00:35Publisher: Taylor & FrancisInforma Ltd Registered in England and Wales Registered Number: 1072954 Registeredoffice: Mortimer House, 37-41 Mortimer Street, London W1T 3JH, UK

Archives of Agronomy and Soil SciencePublication details, including instructions for authors andsubscription information:http://www.tandfonline.com/loi/gags20

Manure and nitrogen fertilizer effectson corn productivity and soil fertilityunder drip and furrow irrigationAbdel F. Berrada a & Ardell D. Halvorson ba Colorado State University, Southwestern Colorado ResearchCenter , Yellow Jacket, USAb USDA-ARS , Fort Collins , CO , USAPublished online: 30 Jan 2012.

To cite this article: Abdel F. Berrada & Ardell D. Halvorson (2012) Manure and nitrogen fertilizereffects on corn productivity and soil fertility under drip and furrow irrigation, Archives of Agronomyand Soil Science, 58:12, 1329-1347, DOI: 10.1080/03650340.2011.590135

To link to this article: http://dx.doi.org/10.1080/03650340.2011.590135

PLEASE SCROLL DOWN FOR ARTICLE

Taylor & Francis makes every effort to ensure the accuracy of all the information (the“Content”) contained in the publications on our platform. However, Taylor & Francis,our agents, and our licensors make no representations or warranties whatsoever as tothe accuracy, completeness, or suitability for any purpose of the Content. Any opinionsand views expressed in this publication are the opinions and views of the authors,and are not the views of or endorsed by Taylor & Francis. The accuracy of the Contentshould not be relied upon and should be independently verified with primary sourcesof information. Taylor and Francis shall not be liable for any losses, actions, claims,proceedings, demands, costs, expenses, damages, and other liabilities whatsoever orhowsoever caused arising directly or indirectly in connection with, in relation to or arisingout of the use of the Content.

This article may be used for research, teaching, and private study purposes. Anysubstantial or systematic reproduction, redistribution, reselling, loan, sub-licensing,systematic supply, or distribution in any form to anyone is expressly forbidden. Terms &Conditions of access and use can be found at http://www.tandfonline.com/page/terms-and-conditions

http://www.tandfonline.com/loi/gags20

http://www.tandfonline.com/action/showCitFormats?doi=10.1080/03650340.2011.590135

http://dx.doi.org/10.1080/03650340.2011.590135

http://www.tandfonline.com/page/terms-and-conditions

http://www.tandfonline.com/page/terms-and-conditions

Manure and nitrogen fertilizer effects on corn productivity and soil

fertility under drip and furrow irrigation

Abdel F. Berradaa* and Ardell D. Halvorsonb

aColorado State University, Southwestern Colorado Research Center, Yellow Jacket, USA;bUSDA-ARS, Fort Collins, CO, USA

(Received 22 March 2011; final version received 8 May 2011)

A field experiment was conducted at the Arkansas Valley Research Center in 2005through 2007 to study the effects of manure and nitrogen fertilizer on corn yield,nutrient uptake, N and P soil tests, and soil salinity under furrow and dripirrigation. Manure or inorganic N was applied in 2005 and 2006 only. There wereno significant differences in corn yield between drip and furrow irrigation eventhough, on average, 42% less water was applied with drip irrigation. Inorganic Nor manure application generally increased grain yield, kernel weight, grain andstover N uptake, and grain P uptake. Nitrogen rates above 67 kg ha71 did notincrease grain yield significantly in 2005 or 2006, nor did manure rates in excess of22 Mg ha71. High manure rates increased soil salinity early in the season,depressing corn yields in 2005 and 2006, particularly with drip irrigation. Saltstended to accumulate in the lower half of the root zone under drip irrigation.Residual nitrate nitrogen from manure and inorganic N application sustainedcorn yields above 12.0 Mg ha71 in 2007. More research is needed to develop bestmanure and drip irrigation management for corn production in the ArkansasValley.

Keywords: corn; nitrogen; water; soil salinity; phosphorus

Introduction

Crop production in the Arkansas River Valley of southwestern Colorado (ArkansasValley) is constrained by water quantity and quality. Thousands of hectares ofcropland have been dried out due to the sale of irrigation water to municipal andindustrial users. Water quantity and quality concerns are exacerbated by the lowefficiency of furrow irrigation, which is widely practiced in the Arkansas Valley.Furrow irrigation application efficiency was estimated at 55% by Gates et al. (2006),who also showed that* 45% of the infiltrated water percolated below the root zone.As water moves across the field or through the soil it dissolves and transports saltsand other pollutants. Return flows contribute * 14% of the total salt load in theArkansas River (Miles, 1977). Excess irrigation, canal seepage and inadequatedrainage increase groundwater level and salt concentration, which contributes to soilsalinization through evapotranspiration (Gates et al. 2006). Salts in the ArkansasValley are dominated by calcium and gypsum precipitates (Cooper et al. 2006).

*Corresponding author. Email: [email protected]

Archives of Agronomy and Soil Science

Vol. 58, No. 12, December 2012, 1329–1347

ISSN 0365-0340 print/ISSN 1476-3567 online

� 2012 Taylor & Francis

http://dx.doi.org/10.1080/03650340.2011.590135

http://www.tandfonline.com

Dow

nloa

ded

by [

134.

117.

10.2

00]

at 0

0:35

30

Nov

embe

r 20

14

In addition to salinity issues, nitrate nitrogen (NO3-N) levels above the WaterDrinking Standard of 10 mg L71 were found in 14% of domestic wells tested in theArkansas Valley in 1994 (Yegert et al. 1997). Contamination sources were notidentified, but elevated NO3-N concentrations may be due in part to N fertilizer ratesin excess of crop needs, as reported in the Arkansas Valley, particularly for vegetablecrops (Bartolo et al. 1997). Halvorson et al. (2002) showed that corn recovered 24%of the residual fertilizer N applied to the previous onion (Allium cepa L.) crop whenno additional N was applied to corn (Zea mays L.). Average N fertilizer useefficiency based on grain N removal over four years was 55% at the lowest fertilizerN rate and 30% at the highest N rate. Soil NO3-N levels declined following thesecond, third, and fourth corn crops (Halvorson et al. 2005).

The Arkansas Valley is home to several concentrated animal feeding operations;thus manure has been used as a substitute or in addition to synthetic fertilizers tosupply nutrients to cultivated crops. However, research to determine manureapplication rates or their effects on crop and soil productivity in the Arkansas Valleyis lacking. Applying manure in excess of crop needs can lead to the build-up of Nand P in the soil and their potential loss by leaching or run-off. At the end of a three-year study in a well-drained silt loam soil in Kentucky, leachate NO3-N of thetreatments that received dairy manure in the spring or fall of each year exceededthose of the ‘N fertilizer only’ treatment (Stoddard et al. 2005). This was attributedto the continued mineralization of N from accumulated manure-derived organicmatter. Nitrate-N concentration of the leachate exceeded 10 mg L71 in the winterwhen soil (0–90 cm) NO3-N was 4 22 kg ha71 after corn harvest. Eghball andPowers (1999) determined N availability from feedlot manure at 40% in the first yearand 18% in the second year after application. Soil P, NO3-N and electricalconductivity (EC) levels were greater in the N-based manure treatments than in theunfertilized check four years after the last manure application was made (Eghballet al. 2004). Manures have a lower N:P ratio than most harvested crops;consequently, N-based manure management often oversupplies the soil with P(Toth et al. 2006). Manures also tend to have high salt contents, which can lead toincreased soil salinity, particularly after repeated applications. Hao and Chang(2003) reported that for every metric ton of salts applied through cattle manure, soilelectrical conductivity of a saturated soil paste extract (ECe) increased by 0.07 dSm71 under irrigated conditions and 0.11 dS m71 under rainfed conditions. Thesmaller increase in ECe under irrigation was due to greater downward movementand leaching of salts compared with the non-irrigated conditions.

Gates et al. (2006) recommended the adoption of efficient irrigation systems toalleviate water shortages and reduce loading of salts and other pollutants such asselenium into the Arkansas River. Surface irrigation using siphons to dischargewater into furrows is the predominant irrigation system in the Arkansas Valley. Itsapplication efficiency rarely exceeds 60%. Much greater efficiency (up to 95%) canbe achieved with sprinkler irrigation (Rogers et al. 1997); however, field shapes orsizes (often 5 40 ha) and pumping costs reduce the appeal for this type of irrigation.By contrast, drip irrigation is used more and more to grow high-value crops such asonion, cantaloupe (Cucumis melo L.), and watermelon [Citrullus lanatus (Thunb.)Matsum. And Nakai]. It is rarely used to irrigate field crops such as corn, unless thelatter is grown in rotation with vegetable crops. Substantial savings in water and Nfertilizer were achieved in western Kansas when corn was irrigated with subsurfacedrip (Lamm et al. 2010). A typical drip irrigation assembly consists of a water source

1330 A.F. Berrada and A.D. Halvorson

Dow

nloa

ded

by [

134.

117.

10.2

00]

at 0

0:35

30

Nov

embe

r 20

14

(pond, well, etc.), pumping station, filtration system, chemical and fertilizer storageand delivery systems, main line, flow meter, valves, pressure regulator and pressuregauges, sub-main, drip lines, and a flushing system (Rogers et al. 2003). Dripirrigation with buried tapes is commonly referred to as subsurface drip irrigation(SDI). The optimum drip tape placement depth and lateral spacing for irrigatingcorn in western Kansas were determined to be 30 and 152 cm, respectively (Lammet al. 2010). SDI must be maintained for at least 10–15 years to competeeconomically with full-size center pivot sprinkler irrigation when growing corn only.

The main objective of this study was to determine the effects of various rates of Nfertilizer and manure on corn yield, N and P uptake, soil salinity, and soil NO3-Nand P test levels under drip and furrow irrigation. A secondary objective was to testthe hypothesis that drip irrigation will conserve water and reduce the leaching ofsalts and NO3-N, compared with furrow irrigation.

Materials and methods

This research was conducted in 2005–2007 at Colorado State University’s ArkansasValley Research Center near Rocky Ford, CO (388202300N, 10384104300W). The soil atthe study site was Rocky Ford clay loam (fine-silty, mixed, calcareous, mesic UsticTorriorthents). Prior to N fertilizer or manure application in 2005, the plot areaaveraged 15 g kg71 of organic matter, 11.9 mg kg71 of sodium bicarbonateextractable P, 298 mg kg71 of ammonium acetate extractable K, electricalconductivity (1:1 soil to water ratio) of 0.8 dS m71, and a pH of 8.1 in the 0–30-cm depth. Nitrate N averaged 7.5 mg kg71 in 0–60 cm.

The experimental design was as a split-plot randomized complete block with fourreplications. SDI or furrow (FrI) irrigation was assigned to the main plots(6.1 6 146.3 m) and fertilizer rate to the subplots (6.1 6 18.3 m). SDI consistedof 22-mm diameter T-tapes with 30-cm emitter spacing and a flow rate of 340 L h71

per 100 m of drip length. They were buried * 20 cm below the soil surface, with acustom-made drip injector, and spaced 152.4 cm apart. Water was pumped from theRocky Ford Canal and filtered with a Spin Clean filter upstream of the drip tapes.Two Netafim 3.8 cm (1½00) M flow meters (one for every two replications) were usedto monitor irrigation water volume during the growing season. Furrow irrigationconsisted of dispensing water from the irrigation ditch, with siphon tubes, to everyother furrow. Water flow for FrI was measured at the top and bottom of selectedfurrows with a 608 V-notch furrow flume. The whole plot area was furrow-irrigatedshortly after the corn was planted to ensure adequate seed germination andemergence. Water was applied every 12 days on average with both SDI and FrI, toreplace crop evapotranspiration (ET). Application timing was dictated by wateravailability and other considerations. Total gross FrI irrigation amounts were102 cm in 2005, 66 cm in 2006 and 62 cm in 2007 (Figure 1). Total SDI irrigationamounts, including the initial furrow irrigation application, were 57, 42 and 35 cm in2005, 2006 and 2007, respectively. FrI application efficiencies were estimated at 40–50% in 2005 and 50–60% in 2006 and 2007. The higher efficiencies in 2006 and 2007resulted from improved management, e.g. by switching to lower diameter siphonsafter water reached the tail end of the plot area. SDI efficiency was probably lessthan optimal (� 95%) due to subbing (surface wetting) and the ensuing evaporativelosses. Subbing can be minimized with deep drip tape placement and reducedirrigation application rate or duration.

Archives of Agronomy and Soil Science 1331

Dow

nloa

ded

by [

134.

117.

10.2

00]

at 0

0:35

30

Nov

embe

r 20

14

A polymer-coated urea was applied to the inorganic N treatments on 10 March2005 and 10 April 2006 at 67.2 kg N ha71 (N1), 134.4 kg N ha71 (N2) and 201.6 kgN ha71 (N3). The highest N rate (202 kg ha71) would be enough to produce 13.6Mg ha71 of corn grain (Davis and Westfall, 2009), assuming that 10.0 kg N ha71 arecontributed by the irrigation water (Halvorson et al. 2005). Two checks wereincluded: no N added (0N) and no N or P added (0NP). Treatments 0N, N1, N2 andN3 also received 25.5 kg P ha71 as triple superphosphate (TSP). Urea and STP werebroadcast with a hand-held spreader. Fresh feedlot beef cattle (Bos taurus) manurewas applied with a Hesston S260 spreader at 22.4 (M1), 44.8 (M2) and 67.2 (M3) Mgha71 on 18 March 2005 and again on 14 November 2005. An informal survey in2004 showed that manure application rates in the Arkansas Valley varied from � 22Mg ha71 to 4 90 Mg ha71, with 45 Mg ha71 being common. In this study,22.4 Mg ha71 of fresh manure would provide enough nitrogen (Table 1) to produce11.2 Mg ha71 of corn grain in 2005 (Davis and Westfall, 2009). The manuretreatments did not receive inorganic N and vice versa. The whole plot area wasdisked after the first manure application and plowed after the second application. NoN or P fertilizer or manure was applied after corn harvest in 2006. The same plotswere maintained throughout the study.

Soil samples (one core per plot) were collected from each plot in the spring(before N fertilizer application) and fall (after corn harvest) of each year todetermine their NO3-N content. Sampling depths were: 0–120 cm in the spring and0–180 cm in the fall, in 30-cm increments. Soil NO3-N was measured using thecadmium reduction method (Mulvaney 1996) using the Lachat QuickChemFIA þ 8000 Series continuous flow analyzer after extraction with 1 M KCl (1:5soil to solution ratio). Sodium bicarbonate extractable P was measured in the 0–30-cm depth in 0NP, M1, M2 and M3 in 2005 and 2006; and 0NP, N2, M1, M2 and M3in 2007. Soil and plant sampling methodology was adjusted based on studyobjectives, parameter to be measured, and available resources.

Soil salinity was assessed using the EC method (Rhoades, 1996). Treatments N2and M2 were sampled in June 2005 at 0–10, 10–30, 30–60 and 60–90-cm soil depthsin SDI and FrI. An excellent correlation was found between EC of 1:1 (soil-to-water

Figure 1. Irrigation and rain amounts in 2005, 2006 and 2007. SDI, subsurface dripirrigation; FrI, furrow irrigation.


Dow

nloa

ded

by [

134.

117.

10.2

00]

at 0

0:35

30

Nov

embe

r 20

14

ratio, by weight) extract and the standard saturated-paste extract (Figure 2). Theformer method saves time, especially if the number of samples is large (Zhang et al.2005). Subsequent EC measurements were made using the 1:1 extract but regularsaturated-paste extracts were used to check measurement accuracy. Sampling forthese measurements was carried out at growth stage V4 (four leaves with collarvisible) in June 2006 and after corn harvest in 2005, 2006 and 2007. The June 2006soil samples were taken within 10 cm of the corn row in N2, M1, M2 and M3 at 0–15, 15–30, 30–60 and 60–90-cm depths. Post-harvest samples were taken in the cornrow, middle of the bed, and furrow in N2 and M2. Sampling depth was 0–15, 15–30and 30–180 cm in 30-cm increments.

Corn hybrid Asgrow RX752RR/YG was planted on 27 April 2005, 21 April 2006and 3 May 2007 at * 91 390 seeds ha71. The previous crop was soybean [Glycinemax (L.) Merrill]. Each plot consisted of eight corn rows spaced 76-cm rows apart.Timely herbicide applications kept the plot area weed-free throughout most of thegrowing season. Hot and dry conditions in July 2005 led to a substantial infestation

Table 1. Selected characteristics of beef feedlot manure applied in the spring and fall of 2005and expected N availability.

Properties

Sampling dateAvailable N(kg ha71)

March 2005 November 2005Manure rate(Mg ha71) 2005b 2006c

Nutrienta

Total N (g kg71) 17.8 17.9 22.4 159.5 232.2Organic N (g kg71) 14.3 14.4 44.8 319.0 464.3NH4-N (g kg71) 3.5 3.5 67.2 478.5 696.5NO3-N (g kg71) 50.05 50.05P (g kg71) 4.0 5.2Water content (g kg71) 408 350Ash content (g kg71) 180 284C:N ratio 13:1 11:1EC (1:5) (dS m71) 24.8 23.4pH 7.6 8.6

Note: aWet basis. b40% of total N available in 2005 from March 2005 application (Eghball and Powers1999). c40% of total N available in 2006 from November 2005 application þ 18% from March 2005application (Eghball and Powers 1999).

Figure 2. Saturated-paste extract EC as a function of 1:1 solution EC.


Dow

nloa

ded

by [

134.

117.

10.2

00]

at 0

0:35

30

Nov

embe

r 20

14

of spider mites (Tetranychus urticae) which was suppressed later by aerial spraying oflabeled insecticides. Preventive spraying was carried out on 27 June 2006 and notreatment was needed in 2007.

Whole plants were cut at ground level from three 1.0-m row lengths at the earlydent growth stage in 2005 and at physiological maturity in 2006. In 2007, a total of15 plants per plot were cut at physiological maturity. The ears and ‘stalks plus leaves’(stover) were separated and weighed. The stover was shredded and a representativesample per plot was weighed, air-dried for several days and dried in a forced-air ovenat 658C for 48 h and weighed again. Six ears per plot were weighed and dried in asimilar manner to determine total (ear þ stover) dry matter. Stover and grain Ncontent was determined using an Elementar vario Macro C-N analyzer (ElementarAmericas, Inc., Mt. Laurel, NJ). The number of plants in the middle of two rowswere counted and harvested for grain on 18 October 2005, 20 October 2006 and 16October 2007. Grain yield was adjusted to 155 g kg71 water content. Grain samplesfrom selected treatments were dried in the oven at 658C for 24 h, weighed, groundand analyzed for total N or P. A subsample of the dried and ground material wasdigested using nitric acid and 30% hydrogen peroxide as described in Jones and Case(1990). Phosphorus concentration in the digest was measured with inductivelycoupled plasma emission spectrometry (ICP). The soil and plant data were analyzedusing the PROC MIXED procedure (SAS, 2002). Treatment effects were deemedsignificant at p ¼ 0.05, unless specified otherwise.

Results and discussion

Corn yield

There were no significant differences in corn grain yield between FrI and SDI in allthree years, despite the fact that, on average, 42% less water was applied with SDIthan with FrI (Tables 2–4). In 2005, the grain yields of 0N and 0NP weresubstantially higher with SDI than with FrI, probably due to more available soilNO3-N at planting (196 kg ha71 in SDI vs. 75 kg ha71 in FrI, in 0–120 cm). Therewas a significant yield reduction in M3 with SDI compared with M1 or the Nfertilizer treatments (Table 2), which could be the result of lower plant population orincreased soil salinity. Plant population in M2 and M3 averaged 6.9 and 6.7 plantsm72, respectively, which was significantly less than in the other treatments. Bycontrast, kernel weight was greater in M2 and M3 probably due to lowercompetition for resources (Table 2).

Corn plant population and growth were likely affected by high salt concentrationin the manure treatments. Manure was applied late (18 March 2005) and was diskedrather than plowed in; hence most of the manure was concentrated in the top 7 cm ofthe soil. This caused a notable increase in soil ECe in M2 (and probably more so inM3, although this was not quantified) compared with N2, at the 0–10-cm depth,particularly under SDI (Figure 3), which may have negatively impacted seedlinggrowth (Willardson et al. 1985; Fipps 2003). A reduction in corn yield can beexpected if ECe 4 1.7 dS m71 (Cardon et al. 2007). The high concentration ofmanure in the seedbed may have also slowed water movement as shown in Figure 4.More water may have been required to reach and imbibe corn seeds in the highmanure-rate treatments due to greater organic matter content, compared with thenon-manure treatments. Miller et al. (2002) reported a significant increase in soilwater retention due to long-term cattle manure application.


Dow

nloa

ded

by [

134.

117.

10.2

00]

at 0

0:35

30

Nov

embe

r 20

14

Table

2.

Corn

grain

yield,yield

components,andN

andPuptakein

2005.

Grain

yield

Grain

Puptake

FrI

SDI

Mean

Plant

population

Kernel

weight

Totaldry

matter

aGrain

Nuptake

Stover

Nuptakea

FrI

SDI

Mean

Fertilizertreatm

ent

(Mgha7

1)

(plants

m7

2)

(mg)

(Mgha71)

(kgha7

1)

(kgha71)

(kgha71)

0N

10.6

12.6

11.6

7.9

351.1

18.4

159.9

39.1

––

–0NP

11.7

13.5

12.6

7.9

339.6

17.8

170.3

35.8

31.4

35.0

33.2

N1

13.1

13.3

13.2

7.9

352.1

20.6

175.4

48.8

––

–N2

13.0

14.2

13.6

8.1

355.3

20.9

188.4

47.1

32.7

36.9

34.8

N3

14.5

14.5

14.5

7.9

359.4

20.8

203.2

47.9

––

–M1

12.6

13.2

12.9

7.7

346.4

19.9

177.3

49.9

35.1

35.8

35.4

M2

12.9

12.7

12.8

6.9

371.7

19.7

189.2

54.6

39.4

33.9

36.7

M3

12.8

11.5

12.2

6.7

369.8

19.1

177.5

55.2

35.2

31.8

33.5

Mean

12.7

13.2

12.9

7.6

355.7

19.6

180.1

47.3

34.8

34.7

34.7

FrI

7.8

SDI

7.5

LSD

(0.05)

1.5

0.4

18.7

NS

17.9

10.9

5.3

Effect

Pr4

FIrrigation

0.38

0.04

0.33

0.97

0.46

0.51

0.98

Fertilizer

50.01

50.01

0.02

0.21

50.01

0.01

0.31

Irr.6

Fert.

0.02

0.30

0.26

0.34

0.14

0.55

0.05

Note:aTotaldry

matter

andstover

Nare

from

thebiomass

samples.Theother

measurementsare

from

thefinalgrain

harvest.NS,notsignificantatp¼

0.05.Irrigation:Frl,

furrow;SDI,subsurface

drip;Mineralfertilizer:0N,noN;0NP,noN

andP;N1,67.2

kgN

ha71;N2,134.4

kgN

ha71;N3,201.6

kgN

ha71;Manure:M1,22.4

Mgha71;

M2,44.8

Mgha71;M3,67.2

Mgha7

1.


Dow

nloa

ded

by [

134.

117.

10.2

00]

at 0

0:35

30

Nov

embe

r 20

14

There was no significant irrigation type by fertilizer treatment effect on cornyield, plant population or kernel weight in 2006 and 2007. Treatments N1, N2, N3,M1 and M2 produced similar grain yields in 2006 but significantly more than 0N or0NP (Table 3). M3 produced significantly less than M1 or N3, probably due to lowerplant population (Table 3) and elevated soil salinity early in the season (Figure 5).

No manure or N fertilizer was applied in 2007 and yet substantial grain yields(12.3–14.6 Mg ha71) were achieved in N2, N3, M1, M2 and M3 (Table 4).Conversely, there was a large reduction in kernel weight and grain yield in 0N, 0NPand N1, as would be expected (see discussion of soil test N). Total dry matteraveraged 20.8 Mg ha71 in 2007 compared with 26.2 Mg ha71 in 2006. Corn seeds(kernels) of M2 and M3 generally weighed more than those of the other treatments(Tables 2–4), probably due to higher rates of N mineralization (and corn N uptake)during grain filling (Ma et al. 1999).

Corn N and P uptake

Grain N uptake was significantly increased by N fertilizer or manure application in2005 and 2006, with the exception of N1 (Tables 2 and 3). This was also reflected in

Figure 3. June 2005 ECe under SDI and FrI in N2 and M2. LSD.05 ¼ 1.54 dS m71.

Figure 4. Wetting pattern shortly after an irrigation event in 2005. Note the poor stand anddry surface in SDI_M3.


Dow

nloa

ded

by [

134.

117.

10.2

00]

at 0

0:35

30

Nov

embe

r 20

14

Table

3.

Corn

grain

yield,yield

components,andN

andPuptakein

2006.

Grain

yield

Plantpopulation

Kernel

weight

Totaldry

matter

aGrain

Nuptake

Stover

Nuptakea

Grain

Puptake

Fertilizertreatm

ent

(Mgha7

1)

(plants

m7

2)

(mg)

(Mgha71)

(kgha7

1)

(kgha71)

(kgha71)

0N

12.4

7.7

320.9

22.3

140.5

60.2

–0NP

12.2

7.7

309.3

22.0

127.6

53.6

32.7

N1

14.5

7.8

339.0

26.5

157.5

64.1

–N2

15.2

7.8

347.0

27.8

178.4

75.8

37.5

N3

15.5

7.7

349.8

28.5

191.8

85.6

–M1

15.9

7.7

347.1

29.1

189.9

87.3

39.7

M2

15.4

7.6

364.4

28.2

189.0

86.8

39.7

M3

14.0

7.2

360.6

25.2

180.7

83.6

36.4

Mean

14.4

7.7

342.3

26.2

169.4

74.6

37.2

LSD

(0.05)

1.4

0.4

17.1

3.7

28.0

17.3

4.6

Effect

Pr4

FIrrigation

0.87

0.22

0.84

0.33

0.97

0.32

0.97

Fertilizer

50.01

0.02

50.01

50.01

50.01

50.01

0.02

Irr.6

Fert.

0.14

0.35

0.55

0.84

0.68

0.79

0.22

Note:aFrom

thebiomass

sampling.Theother

measurements

are

from

thefinalgrain

harvest.Mineralfertilizer:0N,noN;0NP,noN

andP;N1,67.2

kgN

ha71;N2,

134.4

kgN

ha71;N3,201.6

kgN

ha71;Manure:M1,22.4

Mgha7

1;M2,44.8

Mgha71;M3,67.2

Mgha71.


Dow

nloa

ded

by [

134.

117.

10.2

00]

at 0

0:35

30

Nov

embe

r 20

14

the stover N uptake. The relatively low N uptake by corn stalks and leaves (stover) in2005 was probably due to early sampling, which also resulted in low total dry matter(Table 2).

As much or more N were harvested in corn grain of the manure and high N ratetreatments in 2007, compared with 2005 and 2006 (Table 4). Stover N uptake alsoremained high in the treatments, which received manure in the previous two years.Irrigation type had no significant impact on N uptake.

In 2005, grain P uptake was greater in M2 with FrI than with SDI even thoughgrain yields were similar (Table 2). More P was harvested in N2 and in the manuretreatments than in the unfertilized check in 2006 (Table 3). There was a sharpdecrease in grain P uptake in 0NP in 2007 due to low grain yield and soil test P(Tables 4 and 5). Conversely, P uptake in the manure treatments remained relativelyhigh due to the build-up of P in the soil.

Soil test N

After corn harvest in 2005, there was more residual NO3-N in the top 90 cm of soil inN3, M2 and M3 than in 0N, 0NP, N1 or N2 treatments (Table 6). The much higherNO3-N concentrations in the spring of 2006, particularly in M2 and M3, reflect thesecond manure application on 14 November 2005 and N mineralization. Theyclosely match the projected N availability (Table 1).

Soil sampling for NO3-N analysis was carried out a few days before theapplication of N fertilizer (coated Urea) on 10 April 2006. Consequently, the greaterNO3-N levels in the non-manure treatments in the spring of 2006 compared with thefall of 2005 were likely due to unused N from the previous fertilizer application andto N mineralization. At the end of the 2006 growing season, NO3-N in 0–90 cmdropped to levels similar to those observed in the fall of 2005, with the exception ofM3, which averaged 185 kg NO3-N ha71 more in the fall of 2006 (Table 3).Evidently, N released by the high manure treatment exceeded N uptake by thesecond corn crop and may have even depressed grain yield (Table 3). There was littlevariation in NO3-N levels in the spring of 2007 compared with the fall of 2006 withfew exceptions. Nitrate-N levels in the top 90 cm of soil were severely depleted afterthe third corn harvest in the non-manure treatments and in M1 (Table 6). By

Figure 5. June 2006 ECe in N2, M1, M2 and M3 averaged over FrI and SDI. LSD.05 ¼ 1.32dS m71.


Dow

nloa

ded

by [

134.

117.

10.2

00]

at 0

0:35

30

Nov

embe

r 20

14

Table

4.

Corn

grain

yield,yield

components,andN

andPuptakein

2007.

Fertilizertreatm

ent

Grain

yield

(Mgha7

1)

Plant

population

Kernel

weight

Totaldry

matter

aGrain

Nuptake

Stover

Nuptakea

Grain

Puptake

2007

Three-yearaverageb

(plants

m72)

(mg)

(Mgha7

1)

(kgha7

1)

(kgha71)

(kgha71)

0N

8.7

10.9

8.1

307.0

19.0

103.5

35.6

–0NP

7.9

10.9

8.2

301.0

18.4

89.2

28.0

21.82

N1

9.1

12.4

8.3

307.8

19.4

105.1

33.5

–N2

12.3

13.7

8.2

356.5

21.7

160.1

47.6

30.31

N3

14.0

14.7

8.4

373.6

21.6

194.0

59.4

–M1

13.3

14.0

8.0

367.3

21.8

183.8

79.9

35.04

M2

14.6

14.3

8.4

385.8

21.4

214.5

81.1

39.64

M3

14.0

13.4

8.2

388.7

23.5

210.0

98.8

38.41

Mean

11.8

13.0

8.2

348.4

20.8

157.5

58.0

33.00

LSD

(0.05)

2.1

1.3

NS

29.4

NSb

38.0

19.3

4.60

Effect

Pr4

FIrrigation

0.21

0.26

0.24

0.20

0.88

0.45

0.39

0.73

Fertilizer

50.01

50.01

0.17

50.01

0.11

50.01

50.01

50.01

Irr.6

Fert.

0.62

0.27

0.95

0.54

0.68

0.88

0.86

0.20

Note:aFrom

thebiomass

sampling.Theother

measurementsare

from

thefinalgrain

harvest.

bYear6

Irr.interactionissignificantatp¼

0.05andYear6

Fert.interaction

issignificantatp5

0.01.NS,notsignificantatp¼

0.05.Mineralfertilizer:0N,noN;0NP,noN

andP;N1,67.2

kgN

ha7

1;N2,134.4

kgN

ha71;N3,201.6

kgN

ha71;

Manure:M1,22.4

Mgha71;M2,44.8

Mgha71;M3,67.2

Mgha71.


Dow

nloa

ded

by [

134.

117.

10.2

00]

at 0

0:35

30

Nov

embe

r 20

14

contrast, NO3-N concentration in M3 following the 2007 corn harvest would beadequate to produce top corn yields in 2008 without additional N input (Davis andWestfall, 2009). Nyiraneza et al. (2009) reported that long-term application ofmanure significantly increased potentially mineralizable N, pre-plant soil NO3-Nlevels, corn yield and corn N uptake.

When averaged over all treatments, there was significantly more NO3-N(p ¼ 0.086) in the soil profile with SDI (352 kg ha71) than with FrI (213 kg ha71)in the fall of 2007, primarily due to much higher residual N in the manure treatmentswith SDI. The same trend was observed in 2005, although the effect of irrigation typeand irrigation by fertilizer treatment interaction was not significant (data notshown). There were generally higher NO3-N levels in the bottom than in the top90 cm of soil in the fall of 2007, which likely indicates a downward movement ofNO3-N, particularly in M2 and M3 where NO3-N in the 91–180-cm depth increasedevery year (Table 6).

Table 6. Soil NO3-N in the fall of 2005, 2006 and 2007, and the spring of 2007, as affected byfertilizer treatment (averaged across irrigation systems).

Soil NO3-N0–90-cm soil depth

Soil NO3-N90–180-cm soil depth

(kg NO3-N ha71) (kg NO3-N ha71)

Fall Spring Fall Spring Fall Fall Fall FallFertilizer treatment 2005 2006 2006 2007 2007 2005 2006 2007

0N 29 116 37 27 11 111 76 750NP 34 – 28 19 13 105 45 50N1 28 163 52 46 20 53 48 83N2 71 221 99 129 29 162 61 91N3 174 226 136 128 27 57 114 118M1 104 265 106 80 50 206 83 152M2 186 496 197 277 152 97 140 344M3 212 687 397 317 417 69 234 458

Mean 105 311 131 128 90 108 100 171LSD(0.1) 114 141 112 92 208 NS 64 168

Note: NS, not significant at p ¼ 0.05.

Table 5. Soil NaHCO3 extractable P concentration in the 0–30 cm depth in selectedtreatments in 2005–2007.

Soil NaHCO3 extractable P(mg kg71)

Fall Fall Spring FallFertilizer treatment 2005 2006 2007 2007

0NP 9.3 4.7 6.9 7.3N2 NA NA 10.4 6.1M1 19.0 18.0 26.0 18.1M2 41.1 25.5 49.5 39.3M3 37.1 67.0 80.4 44.0Mean 26.6 28.8 34.6 23.0LSD(0.05) 13.8 20.8 30.7 20.5


Dow

nloa

ded

by [

134.

117.

10.2

00]

at 0

0:35

30

Nov

embe

r 20

14

Table

7.

Post-harvestsoilECeunder

SDIandFrI

asaffectedbysamplingpositionanddepth

(averaged

over

N2andM2).

ECe(dSm

71)

Furrow

Row

Bed

center

Soildepth

(cm)

2005

2006

2007

2005

2006

2007

2005

2006

2007

Subsurface

dripirrigation(SDI)

0–15

2.59

0.99

1.35

1.53

1.30

1.28

1.95

2.24

1.32

15–30

2.01

1.20

1.06

1.49

1.63

1.21

1.28

1.67

1.12

30–60

2.06

1.50

1.05

2.38

1.94

1.84

1.12

1.25

1.10

60–90

2.46

1.93

1.75

2.94

2.33

2.64

1.28

1.05

1.25

90–120

2.65

2.23

3.67

2.85

2.96

3.46

1.95

1.52

2.24

120–150

3.32

3.86

5.29

3.63

3.86

5.22

3.26

2.48

4.77

150–180

3.35

3.66

3.81

3.72

4.39

4.98

3.49

3.47

5.26

Mean

2.63

2.20

2.57

2.65

2.63

2.95

2.05

1.95

2.44

Furrow

irrigation(FrI)

0–15

1.38

1.10

1.51

2.01

1.45

1.61

4.25

2.69

2.14

15–30

1.61

1.24

1.37

1.28

1.37

1.44

2.62

4.10

1.95

30–60

2.02

1.23

1.17

1.49

1.25

1.24

1.83

2.74

1.88

60–90

2.03

1.27

1.26

1.91

1.40

1.11

1.52

2.09

2.04

90–120

2.30

1.52

1.45

2.23

1.99

1.72

1.65

2.12

2.72

120–150

2.76

2.36

2.35

2.85

2.60

2.25

2.09

2.43

2.88

150–180

2.58

2.44

2.39

2.94

2.75

2.54

2.01

2.34

2.52

Mean

2.10

1.59

1.64

2.10

1.83

1.70

2.28

2.64

2.30


Dow

nloa

ded

by [

134.

117.

10.2

00]

at 0

0:35

30

Nov

embe

r 20

14

Soil test P

Soil NaHCO3-P concentration in the 0–30-cm depth was highly affected by fertilizertreatment (Table 5). There was significantly more available soil P in the manuretreatments than in the unfertilized check (0NP) or in N2 in the spring of 2007 and fallof each year. Irrigation type did not impact soil test P significantly because diffusion ofP in the soil is very slow (Barber 1980). However, the potential for losing P, e.g.through run-off is much higher with FrI than with SDI. In a furrow-irrigated corn trialin southern Idaho, run-off mass losses of dissolved reactive P (and K) were 2.0–2.4times greater in the manure treatments than in the control (Lentz and Lehrsh 2010).Soil test P in M2 and M3 was well above the sufficiency level of 15–22 mg ha71 forirrigated corn production (Davis andWestfall 2009) in all three years. It was within thesufficiency level in M1, in the fall of each year. M1 produced corn yields similar tothose of M2 and M3 in all three years. Consequently, the greater manure rates werenot justified and could be detrimental to the environment. The Colorado PhosphorusIndex for M2 and M3 at the experimental site (�1% slope and moderate soilpermeability) indicates a medium potential for off-site P movement (Sharkoff et al.2008). Run-off was reduced by irrigating every other furrow; still irrigationapplication efficiency of FrI was 60% or less depending on the year. There was norun-off with SDI, which reduced the risk of P exiting the field, but applying manure inexcess of crop N requirement can lead to other concerns such as increased soil salinity.

Soil salinity

Manure application resulted in significantly greater ECe in the top 30 cm of soil inJune 2005, particularly under SDI, compared with the non-manure treatment(Figure 3). The highest ECe value was 12.2 dS m71 at the 0–10-cm depth in M2,under SDI. Lower ECe values were observed in June 2006 (Figure 5) but a reductionin crop yield could still be expected in the manure treatments since ECe was above

Table 8. Statistical significance of all the factors and their interactions on post-harvest ECein 2005–2007.

EffectNumDF

DenDF

2005F-value

2005Pr 4 F

2006F-value

2006Pr 4 F

2007F-value

2007Pr 4 F

Irrigation type (I) 1 1 0.86 0.524 2.02 0.390 7.54 0.222N or manure rate (F) 1 2 3.16 0.218 19.33 0.048 7.49 0.112I * F 1 2 1.65 0.328 6.81 0.121 0.01 0.924Sampling position (P) 2 8 0.21 0.817 2.23 0.170 0.34 0.720I * P 2 8 0.72 0.516 7.83 0.013 1.39 0.304F * P 2 8 0.26 0.778 0.61 0.566 0.00 0.999I * F * P 2 8 0.08 0.927 4.21 0.056 0.44 0.660Sampling depth (D) 6 72 14.45 5.0001 26.48 5.0001 21.62 5.0001I * D 6 72 2.52 0.028 7.51 5.0001 7.38 5.0001F * D 6 72 1.18 0.328 0.96 0.455 1.53 0.179I * F * D 6 72 0.95 0.464 3.24 0.007 0.56 0.764P * D 12 72 3.63 0.000 5.31 5.0001 0.57 0.862I * P * D 12 72 2.54 0.008 3.22 0.001 1.70 0.086F * P * D 12 72 1.01 0.447 1.82 0.062 0.68 0.767I * F * P * D 12 72 0.83 0.617 2.38 0.012 1.05 0.417


Dow

nloa

ded

by [

134.

117.

10.2

00]

at 0

0:35

30

Nov

embe

r 20

14

Table

9.

SoilECein

Novem

ber

2006asinfluencedbyirrigationtype,

fertilizer

rate,andsamplingpositionandsoildepth.

SDI

FrI

Furrow

Row

Bed

center

Furrow

Row

Bed

center

Soildepth

(cm)

N2

M2

N2

M2

N2

M2

N2

M2

N2

M2

N2

M2

ECe(dSm

71)

0–15

0.98

1.00

0.95

1.65

1.64

2.84

1.07

1.13

1.14

1.76

2.42

2.96

15–30

1.08

1.32

1.23

2.03

1.36

1.97

1.32

1.16

1.04

1.70

2.64

5.57

30–60

1.04

1.95

1.16

2.73

1.18

1.32

1.45

1.00

1.22

1.29

1.74

3.74

60–90

1.23

2.63

1.45

3.21

1.13

0.98

1.52

1.02

1.28

1.51

1.78

2.40

90–120

1.47

2.99

1.93

3.98

1.13

1.91

1.79

1.26

1.97

2.00

1.97

2.26

120–150

2.44

5.29

2.68

5.05

2.19

2.77

2.43

2.28

2.77

2.43

2.25

2.60

150–180

2.90

4.41

2.84

5.95

3.17

3.78

2.39

2.49

3.05

2.44

2.10

2.59

Mean

1.59

2.80

1.75

3.51

1.68

2.22

1.71

1.48

1.78

1.88

2.13

3.16


Dow

nloa

ded

by [

134.

117.

10.2

00]

at 0

0:35

30

Nov

embe

r 20

14

the threshold value of 1.7 dS m71 (Cardon et al. 2007). Differences between SDI andFrI soil ECe values were significant in 2005 but not in 2006.

Manure (M2) had less impact on soil salinity after corn harvest in all three yearsthan it did in June 2005 or 2006, which may be due to salt movement andredistribution in the soil profile with water application and crop uptake. In general,there was greater salt concentration (higher ECe) away from the drip tape (located inthe middle of the bed), i.e. in the furrow or corn row under SDI (Table 7).Conversely, greater ECe values were measured in the bed center than in the furrowunder FrI (Table 7). Irrigation type by sampling depth had a significant impact onECe in 2005 and 2007 (Table 8). Manure application resulted in significantlyhigher ECe values in M2 than in N2 in the fall of 2006, particularly under SDI(Table 9). ECe was generally higher at the bottom half (� 90 cm) of the samplingdepth under SDI than under FrI, especially in 2007. Less water was applied with SDIthan with FrI and thus fewer salts were leached out. However, if one considers thenon-manure treatment only, there was no salt accumulation with SDI comparedwith FrI (Table 9), probably due to the relatively low salt content of the irrigationwater, which had an electrical conductivity of approximately 0.9 dS m71.Furthermore, drip irrigation allows for frequent water applications, which keepsthe soil moist and reduces salt concentration in the soil solution (Fipps 2003),although this (frequent irrigation) was not the case in this study.

Salt accumulation under SDI can be exacerbated if saline well water is used toirrigate the crop, which is often the case in the Arkansas Valley. Gates et al. (2006)reported EC values upstream of John Martin Reservoir of 0.7–1.6 dS m71 forsurface water and 2.4–4.7 dS m71 for ground water. Average crop yield reductionsfrom salinity and water logging were estimated at 11–19% over a three-year period.Growers who adopt drip irrigation often keep their surface irrigation infrastructuresuch as concrete ditches, which gives them the ability to flush out the saltsoccasionally. Some also mix well water with surface water to dilute the salts. Othermanagement practices that can be used to mitigate potentially harmful saltaccumulation under SDI include alternate furrow irrigation, which was used inthis study, and selecting salt-tolerant crops (Cardon et al. 2007).

Conclusions

There were no significant differences in corn yield between SDI and FrI in all threeyears, which indicates that drip irrigation may be a feasible alternative to furrowirrigation for corn production in the Arkansas Valley. However, the drip systemmust be maintained for at least 10 years to justify the relatively high initialinvestment cost (Lamm et al. 2010) if only growing corn. Using drip irrigation wouldeliminate run-off losses and minimize deep percolation; thus greatly reducing theamount of water applied to the field. In this study, 42% less water was applied withSDI than with FrI, on average.

One concern with drip irrigation in this study was the apparent salt accumulationin the root zone. However, most of the accumulation occurred in the high manurerate treatments, which were excessive based on corn yield data. A bigger concern isgetting uniform seed germination and emergence, given the low and erraticprecipitation in the Arkansas Valley and the wide spacing (1.5 m) between thedrip tapes in this study. Growers who can afford to maintain irrigation ditchesshould pre-irrigate their fields before planting corn or other crops. This will not only


Dow

nloa

ded

by [

134.

117.

10.2

00]

at 0

0:35

30

Nov

embe

r 20

14

ensure uniform germination; it will also help flush out salts that may haveaccumulated under SDI.

Corn yields at or near the maximum were produced with 67 kg N ha71 in 2005and 2006 and with 22.4 Mg of manure ha71 (M1) in all three years. Corn yield of M1was similar to that of M2, M3 and N3 in 2007, even though no manure was appliedthat year. The manure rates of 44.8 Mg ha71 (M2) and 67.2 Mg ha71 (M3) resultedin high soil NO3-N concentrations in the spring and fall of 2007. These high manurerates significantly increased salt concentration in the seedbed early in the 2005 and2006 growing seasons, which reduced corn plant population and grain yield at M3,particularly with SDI. Manure had less impact on soil salinity later in the growingseason, probably due to the downward movement of salts and their redistribution inthe soil profile. This study also confirmed the greater leaching potential of salts andNO3

7 with furrow irrigation.There was significantly more available P in the manure treatments than in the

unfertilized check (0NP) or in N2 in the spring of 2007 and fall of each year. Soil testP in M2 and M3 exceeded P sufficiency level for optimum corn production inColorado (Davis and Westfall, 2009). The elevated NO3-N and P levels in the soil ledto increased N and P uptake by corn grain in 2006 and 2007. These results indicatethat applying more than 44.8 Mg of manure ha71 (22.4 Mg ha71 twice) over a three-year period may not only be economically unjustifiable but could also be detrimentalto water quality in the Arkansas Valley. Farmers often use greater manure rates withless frequency however, i.e. every two to four years depending on the crop, to‘increase soil coverage’, reduce transportation costs and prolong the benefits ofmanure on soil fertility and physical properties. Nonetheless, applying the correctamount of N fertilizer or N-based manure would increase nitrogen use efficiency andreduce the risk of groundwater contamination (Halvorson et al. 2005). These benefitscan be enhanced with timely N application, which can easily be achieved with dripirrigation. More research is needed to develop best manure and drip irrigationmanagement for corn production in the Arkansas Valley.

Acknowledgments

This study was funded by the Colorado Department of Public Health and Environment(CDPHE), USDA-NRCS, USDA-ARS, and Colorado State University AgriculturalExperiment Station. The authors would like to thank James Valliant for his leadership inapplying for and obtaining the CDPHE grant and Michael Bartolo for his valuable support insetting up the drip irrigation system. The authors thank K. Tanabe, C. Reule, P. Norris, AminBerrada and B. Floyd for their assistance in sample collection and analytical support inprocessing and analyzing the soil and plant samples. Trade names and company names areincluded for the benefit of the reader and do not imply any endorsement or preferentialtreatment of the product by the authors, Colorado State University or USDA-ARS.

References

Barber SA. 1980. Soil–plant interactions in the phosphorus nutrition of plants. In: KhasawnehFE, Sample EC, Kamprath EJ, editors. The role of phosphorus in agriculture. Madison(WI): ASA/CSSA/SSSA. p. 591–615.

Bartolo ME, Schweissing FC, Valliant JC, Bosley DB, Waskom RM. 1997. Nutrientmanagement of onions: a Colorado perspective. In: Proceedings of the Western NutrientManagement Conference; 1997 March 6–7; Salt Lake City, Utah; 2:114–118.

Cardon GE, Davis JC, Bauder TA, Waskom RM. 2007. Managing saline soils. Crop series no.0.503. Fort Collins (CO): Colorado State University Extension. Available from: http://www.ext.colostate.edu/pubs/crops/00503.html


Dow

nloa

ded

by [

134.

117.

10.2

00]

at 0

0:35

30

Nov

embe

r 20

14

http://www.ext.colostate.edu/pubs/crops/00503.html


Cooper CA, Cardon GE, Davis JG. 2006. Salt chemistry effects on salinity assessment in theArkansas River Basin, Colorado. Colorado Water Resources Research Institutecompletion report no. 206. Forth Collins (CO): Colorado State University.

Davis JG, Westfall DG. 2009. Fertilizing corn. Fact sheet no. 0.538. Forth Collins (CO):Colorado State University Extension. Available from: http://www.ext.colostate.edu/pubs/crops/00538.html

Eghball B, Ginting D, Gilley JE. 2004. Residual effects of manure and compost applicationson corn production and soil properties. Agron J. 96:442–447.

Eghball B, Powers JF. 1999. Phosphorus- and nitrogen-based manure and compostedapplications: corn production and soil phosphorus. Soil Sci Soc Am J. 63:895–901.

Fipps G. 2003. Irrigation water quality standards and salinity management strategies. TexasCooperative Extension. The Texas A&M University System. College Station. B71667.

Gates TK, Garcia LA, Labadie JW. 2006. Toward optimal water management in Colorado’slower Arkansas River Valley – monitoring and modeling to enhance agriculture andenvironment. Agr Exp Sta Tech Rep. TR06–10. Forth Collins (CO): Colorado StateUniversity.

Halvorson AD, Follet RF, Bartolo ME, Schweissing FC. 2002. Nitrogen fertilizer useefficiency of furrow-irrigated onion and corn. Agron J. 94:442–449.

Halvorson AD, Schweissing FC, Bartolo ME, Reule CA. 2005. Corn response to nitrogenfertilization in a soil with high residual nitrogen. Agron J. 97:1037–1278.

Hao X, Chang C. 2003. Does long-term heavy cattle manure application increase salinity of aclay loam soil in semi-arid Alberta? Agr Ecosyst Environ. 94:89–103.

Jones JB Jr, Case VW. 1990. Sampling, handling, and analyzing plant tissue samples. In:Westerman RL, editor. Soil testing and plant analysis. 3rd ed. Soil Sci. Soc. Am., Inc.Madison, WI. p. 389–447.

Lamm FR, Rogers DH, Alam M, O’Brien DM, Trooien TP. 2010. Twenty-one years of SDIresearch in Kansas. Proceedings of the 22nd Annual Central Plains Irrigation Conference,2010 February 23–24; Kearney, NE. Available from: CPIA, 760 N. Thompson, Colby,KS, USA.

Lentz RD, Lehrsh GA. 2010. Nutrients in runoff from a furrow-irrigated field afterincorporating inorganic fertilizer or manure. J Environ Qual. 39:1402–1415.

Ma BL, Dwyer LM, Gregorich EG. 1999. Soil nitrogen amendment effects on seasonalnitrogen mineralization and nitrogen cycling in maize production. Agron J. 91:1003–1009.

Miles D. 1977. Salinity in the Arkansas River Valley of Colorado. Report compiled for theEnvironmental Protection Agency. Rocky Ford (CO): Colorado State Univerity,Arkansas Valley Research Center.

Miller JJ, Sweetland NJ, Chang C. 2002. Hydrological properties of a clay loam soil afterlong-term cattle manure application. J Environ Qual. 31:989–996.

Mulvaney RL. 1996. Nitrogen – inorganic forms. In: Methods of soil analysis, part 3: chemicalmethods. SSSA Book Series no. 5. Madison (WI): SSSA and ASA. p. 1123–1184.

Nyiraneza J, Chantigny MH, N’Dayegamiye A, Laverdiere MR. 2009. Dairy cattle manureimproves soil productivity in low residue rotation systems. Agron J. 101:207–214.

Rhoades JD. 1996. Salinity: electrical conductivity and total dissolved solids. In:Methods of soilanalysis, part 3: chemical methods. SSSABook Series no. 5.Madison (WI): SSSA andASA.p. 417–435.

Rogers DH, Lamm FR, Alam M. 2003. Subsurface drip irrigation (SDI) components:minimum requirements. Kansas State University Cooperative Extension IrrigationManagement Series, MF-2576. Manhattan (KS): Kansas State University.

Rogers DH, Lamm FR, Alam M, Trooien TP, Clark GA, Barnes PL, Mankin K. 1997.Efficiencies and water losses of irrigation systems. Kansas State University CooperativeExtension Irrigation Management Series, MF-2243. Manhattan (KS): Kansas StateUniversity.

SAS. 2002. SAS Software version 9.1. Cary (NC): SAS Institute Inc.Sharkoff JL, Davis JG, Bauder TA, 2008. Colorado phosphorus index risk assessment

(version 4). Agronomy technical note no. 95 (revised). Technical notes. Denver (CO):USDA-NRCS.

Stoddard CS, Grove JH, Coyne MS, Thom WO. 2005. Fertilizer, tillage, and dairy manurecontributions to nitrate and herbicide leaching. J Environ Qual. 34:1354–1362.


Dow

nloa

ded

by [

134.

117.

10.2

00]

at 0

0:35

30

Nov

embe

r 20

14



Toth JD, Dou Z, Ferguson JD, Galligan DT, Ramberg CF Jr. 2006. Nitrogen-vs. phosphorus-based dairy manure application to field crops: nitrate and phosphorus leaching and soilphosphorus accumulation. J Environ Qual. 35:2302–2312.

Willardson LS, Hanks RJ, Hoffman GF. 1985. Soil salinity and corn production. Apublication of the National Corn Handbook Project. Water Management (Drainage),NCH-9. Cooperative Extension Service, West Lafayette (IN): Purdue University.

Yegert M, Austin B, Waskom R. 1997. Ground water monitoring in the Arkansas Valley. Factsheet no. 12. Lakewood (CO): Colorado Department of Agriculture.

Zhang H, Schroder JL, Pittman JJ, Wang JJ, Payton ME. 2005. Soil salinity using saturatedpaste and 1:1 soil to water extracts. Soil Sci Soc Am J. 69:1146–1151.


Dow

nloa

ded

by [

134.

117.

10.2

00]

at 0

0:35

30

Nov

embe

r 20

14

manure and nitrogen fertilizer effects on corn productivity and soil fertility under drip and furrow...

Documents