Surface Compost Effect on Hydrology: In-Situ and Soil Cores

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<ul><li><p>This article was downloaded by: [Karolinska Institutet, University Library]On: 18 November 2014, At: 04:59Publisher: Taylor &amp; FrancisInforma Ltd Registered in England and Wales Registered Number: 1072954 Registered office: Mortimer House,37-41 Mortimer Street, London W1T 3JH, UK</p><p>Compost Science &amp; UtilizationPublication details, including instructions for authors and subscription information:http://www.tandfonline.com/loi/ucsu20</p><p>Surface Compost Effect on Hydrology: In-Situ and SoilCoresS. D. Logsdona &amp; R. W. Maloneaa USDA-ARS, NLAE, Ames, IowaPublished online: 07 Nov 2014.</p><p>To cite this article: S. D. Logsdon &amp; R. W. Malone (2015) Surface Compost Effect on Hydrology: In-Situ and Soil Cores,Compost Science &amp; Utilization, 23:1, 30-36, DOI: 10.1080/1065657X.2014.949909</p><p>To link to this article: http://dx.doi.org/10.1080/1065657X.2014.949909</p><p>PLEASE SCROLL DOWN FOR ARTICLE</p><p>Taylor &amp; Francis makes every effort to ensure the accuracy of all the information (the Content) containedin the publications on our platform. However, Taylor &amp; Francis, our agents, and our licensors make norepresentations or warranties whatsoever as to the accuracy, completeness, or suitability for any purpose of theContent. Any opinions and views expressed in this publication are the opinions and views of the authors, andare not the views of or endorsed by Taylor &amp; Francis. The accuracy of the Content should not be relied upon andshould be independently verified with primary sources of information. Taylor and Francis shall not be liable forany losses, actions, claims, proceedings, demands, costs, expenses, damages, and other liabilities whatsoeveror howsoever caused arising directly or indirectly in connection with, in relation to or arising out of the use ofthe Content.</p><p>This article may be used for research, teaching, and private study purposes. Any substantial or systematicreproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in anyform to anyone is expressly forbidden. Terms &amp; Conditions of access and use can be found at http://www.tandfonline.com/page/terms-and-conditions</p><p>http://www.tandfonline.com/loi/ucsu20http://www.tandfonline.com/action/showCitFormats?doi=10.1080/1065657X.2014.949909http://dx.doi.org/10.1080/1065657X.2014.949909http://www.tandfonline.com/page/terms-and-conditionshttp://www.tandfonline.com/page/terms-and-conditions</p></li><li><p>Surface Compost Effect on Hydrology: In-Situand Soil Cores</p><p>S. D. Logsdon and R. W. Malone</p><p>USDA-ARS, NLAE, Ames, Iowa</p><p>ABSTRACT. Compost increases water-holding capacity and total porosity. Improved soil structuremay increase volume of macropores, allowing better drainage, air-exchange, and root growth. Thepurpose of this study was to compare water retention curves and hydraulic conductivity for packedcolumns with and without additions of surface compost. Columns packed with subsoil (around 60 cmlong) had either compost or topsoil added to the surface. Tensiometers and hydra probes monitoredsoil pressure head and water content during three wetting and evaporation cycles. The columns withcompost had significantly smaller bulk density at the surface than columns with topsoil (0.87 versus1.34 g cm3). Surface compost amendment resulted in more water when satiated (0.617 versus0.422 m3 m3) and at 100 cm head (0.377 versus 0.276 m3 m3) than for topsoil at the surface,indicating a greater fraction of larger pores for the compost amended. Whole column infiltration ratewas significantly faster for columns with compost than without (1.46 versus 1.11 cm min1);however, saturated hydraulic conductivity (rate water flows through soil) on soil cores was notsignificantly affected by compost. Subsoil water flow and drainage was not significantly affected bysurface compost. For the subsoil, in-situ column drying was significantly drier than core drainage atthe wet end. There were no significant differences in whole column or surface water retention orevaporation rate. Perhaps the trend towards better water-holding capacity in the compost treatmentwas offset by larger pores and faster drainage, resulting in no significant difference between compostand topsoil.</p><p>INTRODUCTION</p><p>Urban soil is often compacted after construc-tion. The original topsoil has been removedwith only minimal topsoil added after construc-tion. The compaction hinders growth of lawns,shrubs, and trees (ONeil and Carrow 1983).Infiltration is reduced, which results inincreased runoff and erosion (Maniquiz et al.2009).</p><p>Faucette et al. (2005) showed that surfacemulch significantly reduced runoff comparedwith the control without surface mulch. Persyn</p><p>et al. (2004) showed that various types of sur-face-applied compost all significantly reducederosion compared with non-vegetated or vege-tated controls without compost for highwayconstruction areas. Tyner et al. (2011) showedthat surface-applied mulches and composts allreduced erosion on construction sites, but ero-sion control mats reduced erosion the most.</p><p>Johnson et al. (2006) added compostedmanure to the surface of turf, but did notobserve any effect on soil water content. Singeret al. (2006) showed that surface applied com-post only increased soil water right after a rain;</p><p>This article not subject to US copyright law.Correspondence to: S. D. Logsdon, USDA-ARS, NLAE, 2110 University Blvd., Ames, IA 50010.</p><p>E-mail: sally.logsdon@ars.usda.gov</p><p>30</p><p>Compost Science &amp; Utilization, 23:3036, 2015ISSN: 1065-657X print / 2326-2397 onlineDOI: 10.1080/1065657X.2014.949909</p><p>Dow</p><p>nloa</p><p>ded </p><p>by [</p><p>Kar</p><p>olin</p><p>ska </p><p>Inst</p><p>itute</p><p>t, U</p><p>nive</p><p>rsity</p><p> Lib</p><p>rary</p><p>] at</p><p> 04:</p><p>59 1</p><p>8 N</p><p>ovem</p><p>ber </p><p>2014</p></li><li><p>however, incorporated compost more fre-quently increased soil water content.</p><p>Compost sometimes increases water holdingcapacity in the compost addition (Cogger 2005;Giusquiani et al. 1995), but the effect on sub-soil is not clear. Since water content isincreased at both the wet and dry end, the plantavailable water may not be increased by com-post additions (Cogger 2005). The purpose ofthis study was to compare water retentioncurves and hydraulic conductivity for packedcolumns with and without additions of surfacecompost.</p><p>MATERIALS AND METHODS</p><p>Six polyvinyl chloride (PVC) columns werebuilt for the study, having a diameter of 30 cmand a drainhole. The columns were packedlayer-by-layer with Nicollet clay loam subsoil(fine-loamy, mixed, superactive, mesic AquicHapludoll; Soil Survey Staff 2010). Then, 160to 180 mm of water were added and the col-umns were covered to equilibrate. Surface addi-tions were either 3 cm of soil (treatment 1) oryard-waste compost (treatment 2), resulting inthree replicates of each treatment. The compostwas 1.7% total nitrogen, 0.27% total phospho-rus, 0.83% total potassium, 34.8% organic car-bon with a pH of 7.5 and with 91% of particles</p></li><li><p>Saturated hydraulic conductivity was deter-mined by the falling head method (Klute andDirksen 1986), followed by desorption. Thenthe samples were dried to determine bulk den-sity (Blake and Hartge 1986). Leaks in some ofthe Tempe cells occurred, resulting in somemissing data. At the most negative pressurehead (700 cm), only 9 of the 36 cores did notleak, so the 700 cm data are not used. At500, 300, and 100 cm head levels, 24, 30,and 34 of the cores provide useful non-leakingdesorption data, but all 36 cores had satiateddata (near saturation with some free drainage).These head levels were used even with themissing data. Intermediate head levels (50,200, 400) were interpolated between themeasured data.</p><p>Instantaneous profileevaporation calculatedwater retention curves were compared withTempe cell data. The instantaneous profilemethod interpolates soil water and pressurehead simultaneously from measurements,whereas pressure heads are applied to theTempe cells. Also, the columns with compostwere compared to the columns with surfacetopsoil for instantaneous profile desorption, andfor undisturbed core Ksat, bulk density, anddesorption. Hydraulic conductivities were log-transformed for statistical comparisons thengeometric means were given for presentation.</p><p>Calibrated load cells installed at the base ofthe columns were used to assess change in soilwater within each column. Mass balance frominflow, outflow, and load cells was calculated.For each cycle and column, the amount of drain-age was subtracted from the amount of wateradded, and divided by the soil volume. Themaximum wetting indicated by the load cellwas converted to cm3 and divided by the soilvolume. The one day drainage after this maxi-mum wetting was determined from the load celldata and divided by the soil volume. The oneday evaporation rate was determined from day 1to day 2 after removing the covers from the col-umns, and then divided by the soil volume. Thelong-term evaporation rate was determinedfrom the slope of the load cell water loss overtime, and was also divided by the soil volume.Compost and no compost treatments were com-pared by analysis of variance considering cycle</p><p>as the block. Similar water balance was calcu-lated from near surface hydra probe data.</p><p>Water content at given desorption head lev-els were compared between column and coredata by analysis of variance, blocked by col-umn. Saturated hydraulic conductivity (of coresextracted from columns) and infiltration rates(of columns) were log-transformed before sta-tistic analysis. The two treatments (compostversus topsoil) were compared by t-test fortransformed values as well as untransformedbulk density and sub-surface water contents ata given head level of desorption. All differen-ces were considered significant at the p D 0.05level.</p><p>RESULTS AND DISCUSSION</p><p>The instantaneous profile procedure alloweda more continuous curve for desorption (figures 1and 2) and for unsaturated hydraulic conductiv-ity (figures 3 and 4). The core technique alloweda broader range of pressure heads to be evalu-ated. Theoretically, a tensiometer should have arange close to 800 cm; however, cavitationcan occur at wetter values, and evaporation maynot be rapid enough to get drier soil values. Thesurface soil or compost dried rapidly beyond therange of the tensiometers. In addition, lowerdensity might have reduced contact between ten-siometer and media. For the subsoil, the</p><p>FIGURE 1. Example column and core watercontent as a function of pressure head for thesubsoil of column 2, no compost at surface.</p><p>32 Logsdon and Malone</p><p>Dow</p><p>nloa</p><p>ded </p><p>by [</p><p>Kar</p><p>olin</p><p>ska </p><p>Inst</p><p>itute</p><p>t, U</p><p>nive</p><p>rsity</p><p> Lib</p><p>rary</p><p>] at</p><p> 04:</p><p>59 1</p><p>8 N</p><p>ovem</p><p>ber </p><p>2014</p></li><li><p>instantaneous profile calculations on the columnwere significantly drier at 50 and 100 cmhead compared with the Tempe core data (table2). Differences were not significant at drier headlevels. Basile et al. (2006) also observed thatwet end core desorption was wetter than instan-taneous profile method in the field, which theyattributed to different initial conditions. Theyused a scaling procedure to make the desorptiondata better match the field data.</p><p>Saturated hydraulic conductivity was notsignificantly affected by surface compost(table 3); however, bulk density was signifi-cantly reduced within the surface layer thatcontained the compost. Subsurface bulk</p><p>densities were not significantly affected by sur-face compost. Infiltration rate that surfaceapplied water entered the columns was signifi-cantly faster for the compost-amended columns(table 3). Unsaturated hydraulic conductivityvalues (table 4) were numerically higher for thesubsoil of the surface compost treatment; how-ever, there were not enough data for statisticalcomparisons.</p><p>Others (Arthur et al. 2012; Brown and Cot-ton 2011; Civeira 2010; Curtis and Classen2009; Thompson et al. 2008) also observedreduced bulk densities with compost addition.Compost reduces bulk density partly becausethe particle density of organic matter is lessthan soil minerals; however, over time soilstructure development results in increased</p><p>FIGURE 2. Example column and core watercontent as a function of pressure head for thesubsoil of column 3, compost at surface.</p><p>FIGURE 3. Unsaturated hydraulic conductivityfor the subsoil of column 2, no compost at sur-face.</p><p>FIGURE 4. Unsaturated hydraulic conductivityfor the subsoil of column 3, compost at surface.</p><p>TABLE 2. Subsurface water content as afunction of pressure head comparison of column</p><p>(16 cm) vs. core (2531 cm)</p><p>Head Core Column</p><p>(cm) (m3 m3) (m3 m3)</p><p>50 0.406 a 0.282 b100 0.323 a 0.254 b200 0.314 a 0.248 b300 0.272 a 0.243 a400 0.227 a 0.230 a500 0.236 a 0.213 aNote: Means within rows followed by the same letter are not signifi-</p><p>cantly different.</p><p>SURFACE COMPOST EFFECT ON HYDROLOGY: IN-SITU AND SOIL CORES 33</p><p>Dow</p><p>nloa</p><p>ded </p><p>by [</p><p>Kar</p><p>olin</p><p>ska </p><p>Inst</p><p>itute</p><p>t, U</p><p>nive</p><p>rsity</p><p> Lib</p><p>rary</p><p>] at</p><p> 04:</p><p>59 1</p><p>8 N</p><p>ovem</p><p>ber </p><p>2014</p></li><li><p>porosity (Cogger 2005). After three years, soilbulk density was significantly reduced for halfof the composts tested (Tejada et al. 2009),suggesting improved soil structure over time insome cases. Additions of compost result inmore rapid infiltration (Brown and Cotton2011; Civeira 2010; Cogger 2005). Peatincreased saturated hydraulic conductivitywhen added to a silt loam soil, but not whenadded to a loam soil (McCoy 1998).</p><p>Within the column data for instantaneousprofile calculations in the subsoil, the surfacecompost treatment was significantly drier at50 and 100 cm heads than the surface top-soil treatment (table 5). Differences were notsignificant at drier heads. Tempe core desorp-tion of the subsoil did not show significant dif-ferences between treatments except the surfacetopsoil columns had more water at 100 cmhead than did the surface compost columns(table 6). The surface samples were signifi-cantly wetter for the compost treatment thanfor the treatment with surface topsoil when sati-ated and at 50 and 100 cm heads (table 7),</p><p>suggesting a greater volume of larger pores inthe compost treatment.</p><p>Water balance calculations (table 8) did notshow any significant differences between com-post and no compost columns for water reten-tion during watering (addition minus drainage),early drainage, maximum wetting, early evapo-ration rate, long-term evaporation rate, whetherwhole column (from load cells) or surfacewater (from hydra probes). There was a lot ofvariability among the cycles, and some vari-ability among the columns. Note that the wholecolumn retention (add-drain) was 0.087 versus0.095 m3 m3 for the columns with compost atthe surface versus columns with topsoil at thesurface (table 8). Conversely the change in sur-face water (net surface retention) was 0.094versus 0.072 m3 m3 for the columns withcompost at the surface versus columns withtopsoil at the surface. Because the compost ortopsoil was a small part of the whole column,the non-significant trend in water retention wasreversed from expectations, and from the trendfor the surface soil water only.</p><p>TABLE 3. Saturated hydraulic conductivity Ksat, bulk density, and whole column infiltrationcomparisons of columns with compost or topsoil</p><p>Ksat Bulk density Infiltration</p><p>Depth Compost Topsoil Compost Topsoil Compost Topsoil</p><p>(cm) (...</p></li></ul>

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