|
Table 4. Effect of fertility treatments on yields from trench
<br />plots and undisturbed plots.
<br />Fertility
<br />N -P
<br />kg ha -'
<br />Corn Corn Corn Corn
<br />Wheat Barley silage grain Wheat silage grain
<br />1979 1980 1981 1981 1982 1983 1983
<br />Mg lm -,
<br />Trench plots
<br />0 -0 1.12 0.47 23.7 3.83 1.44 14.1
<br />34 -22 1.11 0.48 17.8 2.69 1.43 14.0
<br />67 -45 1.07 0.40 18.2 3.11 1.39 13.5
<br />. Avg 1.10 0.46 19.9 3.21 1.42 13.9
<br />HSD (0.05)
<br />FERTt NS NS 4.7 NS NS NS
<br />SPO x FERT NS NS NS NS NS NS
<br />Undisturbed plots
<br />0-0 1.19 0.70 24.7 3.94 1.76
<br />34 -22 1.03 0.85 24.0 3.97 - 1.70
<br />67 -45 1.12 0.68 24.6 3.56 1.70
<br />14.6
<br />13.6
<br />12.4
<br />Avg 1.11 0.74 24.4 . 3.82 1.72 13.5 .
<br />HSD (0.05)
<br />FERT NS NS - NS NS NS NS .NS
<br />t FERT = fertility treatments, SPO = spoil and subsoil treatments.
<br />cantly affected by either spoil texture or topsoil thick- _
<br />ness, although they did tend to increase with topsoil
<br />thickness (Table 3). Responses to subsoil /spoil and
<br />topsoil treatments were similar on irrigated and non, -
<br />irrigated plots in 1983 (Tables 2 and 3). Both silage
<br />and corn grain yields were sigkificantly *highs ;,in1983
<br />on trenches with subsoil or finer - textured_ spoil than:
<br />on trenches with loamy sand, spoil. Corn silage 'yields
<br />were usually higher on 0.46 or 0.69 in of topsoil thali '.
<br />on 0.23 m. Yield responses 'to topsoil.�thickness' on
<br />irrigated plots occurred in part because . the supple=
<br />mental water was added late in ;the growing
<br />when corn, corn, especially that growing on 0,23 m of top
<br />soil over loamy sand, was already exhibiting moisture
<br />stress. This stress was probably ,sufficient, ,to'
<br />yields on plots with 0.23 zn of topsoil comparedr:to
<br />0.69 m even though supplemental. water was ;then
<br />added. ;- .,{
<br />The addition of N and' P fertilizer did not affect
<br />yields in any year except 1981 when corn silage`yields
<br />were reduced by the application of N and P fertilizer
<br />(Table 4). Plots on undisturbed soil nearby received
<br />fertilizer treatments equivalent to those on the trench
<br />plots. Yields from the undisturbed plots were not sig-
<br />nificantly affected by fertilizer additions in any year
<br />of the study (Table 4). The native fertility of the soil
<br />was sufficient to supply the nutrients for maximum
<br />yields under the climatic conditions of the site. Av-
<br />erage yields in 1979 and 1983 from the trenches were
<br />equal to or better than yields on undisturbed plots.
<br />SUMMARY AND CONCLUSIONS _
<br />Yields of crops grown for 5 yr following simulated
<br />reclamation of strip -mined land generally increased
<br />with increasing thickness of topsoil. The largest in-
<br />crease was on trenches filled with loamy sand spoil.
<br />Yields on trenches with subsoil placed over loamy sand
<br />spoil, were higher for a given topsoil thickness than
<br />on trenches without subsoil, although yields from plots
<br />with 0.69 m of topsoil were not significantly different
<br />between plots with and without subsoil. Topsoil and/
<br />or subsoil thickness of at least 0.7 m should be spread
<br />for highest yields on coarse textured nonsodic spoil.
<br />Since the subsoil, clay loam spoil, and silty clay loam
<br />spoil had a greater ability to supply water to the grow-
<br />ing crop throughout the growing season than the loamy
<br />sand, 0.46, to 0.69 m of topsoil was sufficient for max-
<br />imum productivity. ; `- = - ' =
<br />1.71 Selected plots irrigated in.1982 and 1983 had greatly
<br />1.09 , improved yields compared to nonirrigated plots.
<br />0.52 Wheat grown on *irrigated plots in 1982 did not re-
<br />1.11 spond signlficant1y to topsoil thickness or subsoil /spoil
<br />NS treatments..�On i rigated plots in 1983, response of sil-
<br />0.79 - age and : corn grain" to' subsoil /spoil treatments was
<br />similar to - the nonirrigated plots. No response to N
<br />and P fertilizeeWas observed on the trench plots or
<br />nearby;uiidistulbedp1ots Average yields in '1979
<br />o.00 and 1983 from the _trenches :were equal to ,or better
<br />0.61 tha "yields`�on plots. '
<br />A KNOVLEDGMENTS
<br />.� �
<br />,r.rs x c _ t ,. i ' : .
<br />uthors S piess Ppreciation to L V. Zimmerman,
<br />F.S. "Carte % ;t Thomas,' and D, D. 'Schlenker for tech -
<br />`:pical' assistance; R: :Stastny for typing this Manuscript; Drs.
<br />R ,;Sojka; , E `; c:;poll,-and E. •Diebert or their counsel; F. "
<br />Scht+oerforbis.Work on locating and characterizing spoil and
<br />hoti, dad the'Falldrk Mining Company for assis- --
<br />ice "and _iinancial.aupport of this project.
<br />REC1S
<br />19841 Soil depth requirements' of ;
<br />: brined areas'in Wyoming, Montana, and
<br />_ . ' QuaL 3 -+404 = `:
<br />Whey 19 Soluble salts:7n C.A. lack it'
<br />ethod o analysis.Agronorny 9:933 =951. ter.„
<br />Darsoori, ,14 1 198(t<Reobitimended potassium test. p. 17 -18. In W.0
<br />Dahnke e ) tecnitimended 'chemical soil test procedures for the
<br />Reeidn. North Dakota Agric. Exp. Stn. BuIL 499
<br />(reviued ' . d'
<br />P,R:. Particle fractionation and particle -size analysis. In
<br />'Black et aL red.), Methods of soil analysis. Agronomy 9:545 ,
<br />b11,.1LC S s G.A. ',Halvorson. 1984. Soil replace= •
<br />went for, tion of s lands in North Dakota. North
<br />• Dako . Stn. iinli 514. - " a " >. ` '; k `
<br />Knud�n mw,ended phosphorus tests: p. 14-16. In`
<br />tw,15ahlke, iR ecomntended,chemical soil test procedures .
<br />:for the North Central Region. North Dakota Agric. Exp. Stn. Bull.
<br />` 499 ( r e v i s e d_ : > .
<br />Merrill, &D., F.M. Sandoval, J.F. Power, and E.J. Doering. 1980.
<br />,Salinity and sodicityi factors "affecting suitability 'of materials for
<br />; llaanndreclamation. p'. 3-1 id 3-25. In Adequate reclamation
<br />of mined lands? Synip. Prot,, Billings; MT. 26-27 Mar: '1980. Soil
<br />';'` Conservation Society of America, Ankeny, IA.
<br />Peech, M. 1965.. Hydrogen -ion activity. In C.A. Black et al. led.)
<br />• Methods of soil analysis. Agronomy 9:914 -926.
<br />oIe M.W. 'A: Bauer, L:V. Zimmerman, and S.W. Melsted'1979.
<br />Weds topsoil thickness placed on spoil banks on 'wheat and
<br />L corny i eldsin -North Dakota. p. 138 -155. In Proc. Annual Meet-
<br />. ;ins Canadian Land Reclamation Association 4th. Regina, Sas;
<br />katchewan, Canada. 13-15 July. 1973. V
<br />Power, J:R; FA: Sandoval, R.E. Ries, and S.D. Merrill. 1981. Ef-
<br />1 facts of.topsoil and subsoil thickness on soil water content and
<br />cropp production on a disturbed soil. Soil Sci. Soc. Am. J. 45:124 -
<br />Richards, A.' 1965. Physical condition of water in soil. I n
<br />L C.A.
<br />;Black et aL•(ed) Methods of soil analysis. Agronomy 9:128 -152.
<br />Wali, M.K., -and F.M. Sandoval. 1975. Regional site factors and
<br />revegetation studies -in western North Dakota. p. 133 -153. In .
<br />4 :Practices and problems of land reclamation in western North
<br />• America. University of Grand Forks Press, Grand Forks, ND.
<br />Wollenhaupt, and J.L. Richardson. 1982. The role of topog-
<br />_ raphy in revegetation of disturbed lands. p. C -2 -1 to C -2 -11. In
<br />F.F. Munshower et al. (ed.) Mining and reclamation of coal mined
<br />• lands in the Northern Great Plains. Symp. Proc., Billings, MT.
<br />8-9 Mara Montana State University, Bozeman, MT. .
<br />
|