Loamy Sand Site Research Articles

Assessing the Impact of Different Irrigation Levels on Starch Potato Production

In the view of increasing water demands in agriculture, efficient water use is a key factor in potato production. The aim of this study was to compare two deficit (80% and 90%) and one abundant (120%) gun sprinkler irrigation levels with the longtime used irrigation level of a farmer (100%). Irrigation was supplied during the 2021 growing season on a loamy sand site in Mecklenburg–Western Pomerania, Germany. Yield and tuber quality of the high-amylopectin potato (HAPP) variety “Waxy/Henriette” were assessed in a three-grade tuber size distribution. Five economic indicators were used to assess the suitability of the investigated irrigation levels to secure economic responses. Yield and starch yield did not significantly differ between the 90% (561.1 dt ha−1 and 102.0 dt ha−1) and the 100% irrigation levels (559.1 dt ha−1 and 102.3 dt ha−1), with total production increasing by 2.0 dt ha−1 and starch production decreasing by 0.4 dt ha−1 at the 90% irrigation level. Tuber lesions decreased the economic responses at all irrigation levels. Potentially, 87,469 m3 of irrigation water (125.8 m3 ha−1) could have been saved on the loamy sand starch potato sites of the local farm (695.3 ha) in 2021.

The establishment of winter wheat root system architecture in field soils: The effect of soil type on root development in a temperate climate.

Winter wheat (Triticum aestivum L.) is an important cereal crop in the temperate climates of western Europe. Root system architecture is a significant contributor to resource capture and plant resilience. However, the impact of soil type on root system architecture (RSA) in field structured soils is yet to be fully assessed. This work studied the development of root growth using deep cultivation (250mm) during the tillering phase stage (Zadock stage 25) of winter wheat across three soil types. The three sites of contrasting soil types covered a geographical area in the UK and Ireland in October 2018. Root samples were analysed using two methods: X-ray computed tomography (CT) which provides 3D images of the undisturbed roots in the soil, and a WinRHIZO™ scanner used to generate 2D images of washed roots and to measure further root parameters. Important negative relationships existed between soil bulk density and root properties (root length density, root volume, surface area and length) across the three sites. The results revealed that despite reduced root growth, the clay (Southoe) site had a significantly higher crop yield irrespective of root depth. The loamy sand (Harper Adams) site had significantly higher root volume, surface area and root length density compared with the other sites. However, a reduction in grain yield of 2.42Mt ha-1 was incurred compared with the clay site and 1.6Mt ha-1 compared with the clay loam site. The significantly higher rooting characteristics found in the loamy sand site were a result of the significantly lower soil bulk density compared with the other two sites. The loamy sand site had a lower soil bulk density, but no significant difference in macroporosity between sites (p>0.05). This suggests that soil type and structure directly influence crop yield to greater extent than root parameters, but the interactions between both need simultaneous assessment in field sites.

Organic matter amendments improve soil fertility in almond orchards of contrasting soil texture

The effects of organic matter amendments (OMA) on soil fertility in permanent cropping systems like orchards is under-studied compared to annual cropping systems. We evaluated experimentally the impact of OMAs on soil fertility in almond (Prunus dulcis) orchards over a two-year period with annual applications. Two OMAs, derived from composted green waste (GWC) or composted manure wood chips (MWC), were applied as surface mulch and compared to a control at two sites with different soil textures (sandy loam and loamy sand). OMAs increased soil moisture content (0–0.1 m depth) at both sites by 27–37%. Both amendments increased soil inorganic N at the sandy loam (GWC: 194%; MWC: 114%) and loamy sand (GWC: 277%; MWC: 114%) sites the month following application, but soil inorganic N concentrations quickly decreased to values similar to those of control plots. After two-years, the GWC and the MWC amendments increased the soil cation exchange capacity (CEC) by 112% and 29%, respectively, in the sandy loam site, but no change was observed in the loamy sand site. The greatest increase in soil extractable K occurred in the GWC-amended plots at the sandy loam site even though the initial K concentration of MWC was higher. Both OMAs increased soil organic carbon (SOC) after two years, but the SOC increase in the GWC-amended plots was greater. Our results suggest that OMAs can significantly improve soil fertility after one or two annual applications, and that fertility gains appear to be dependent on soil texture than the nutrient concentrations of the OMA.

Nitrogen management considerations for landspreading municipal solid waste compost.

Many municipalities have examined composting as an alternative to landfilling for the management of organic solid waste materials. Ultimately these materials will be land-applied and therefore some knowledge of nutrient availability will be necessary to optimize crop yield and minimize environmental risk. Field studies were conducted in 1993 and 1994 on a silt loam and a loamy sand soil in Wisconsin to determine the effect of municipal solid waste compost (MSWC) on corn (Zea mays L.) yield, plant nutrient concentration, and soil nitrate N content. Municipal solid waste composts with ages of 7, 36, and 270 d were applied at rates of 22.5, 45, and 90 Mg ha(-1) to small plots. Rates of commercial nitrogen (N) fertilizer, ranging from 0 to 179 kg N ha(-1), were applied to separate plots to determine the N availability from the MSWC. Treatments were applied in the spring and incorporated before planting corn. The 270-d MSWC increased corn whole-plant dry matter and grain yield at each location in both years above the 7- and 36-d MSWC. Rate of MSWC only affected grain yield at the loamy sand site in 1994. Municipal solid waste compost had minimal effect on the levels of plant nutrients in the whole-plant tissue measured at physiological maturity. Nitrate N measured in the top 90 cm of soil was higher throughout the growing season in treatments receiving recommended N fertilizer when compared with any of the MSWC treatments. It was estimated that 6 to 17% of the total N in the 270-d MSWC became available in the first year. The land-application of mature MSWC at the tested rates would be an agronomically and environmentally admissible practice.

N rate and transport under variable cropping history and fertilizer rate on loamy sand and clay loam soils: II. Performance of LEACHMN using different calibration scenarios

Testing of existing agronomic models is needed to ensure their validity and applicability to different soils, cropping systems and environments. Data collected from a 3-year field experiment of maize (zea mays L.) on a loamy sand and a clay loam soil were used to validate the research version of the LEACHMN model for water flow and N fate and transport. Three calibration scenarios with increasing levels of generalization for transformation rate coefficients were used based on: (i) each year, treatment and soil type (ii) 3-year average values for each treatment and soil type, and (iii) average over years and soil types. Model accuracy was tested using both graphical and statistical methods including 1:1 scale plot, root mean square error and normalized root mean square error, and correlation coefficient values. The model accurately predicted drainage water flow rate and volume under both sites. Calibrated N transformation rate constants for each treatment, year and soil type provided satisfactory predictions of growing season cumulative NO3–N leaching losses, and accurate predictions of growing season cumulative maize N uptake at both sites. The use of 3-year average rate constant values for each site resulted in fairly satisfactory predictions of NO3–N leaching losses on the clay loam site, but inaccurate predictions on the loamy sand site. The model provided accurate predictions of cumulative maize N uptake for both sites. Using the rate constant values averaged over years and soil types resulted mostly in inaccurate predictions. Use of year and soil type-specific N rate coefficients results in accurate LEACHMN predictions of N leaching and maize N uptake. When rate coefficients are generalized over years for each soil type, satisfactory model predictions may be expected when N dynamics are not strongly affected by yearly variations in organic N inputs.

Effect of applied phosphorus on the growth of Lupinus luteus, L. angustifolius and L. albus in acidic soils in the south-west of Western Australia

Phosphorus is the major nutrient element deficiency of grain legumes in the south-west of Western Australia. Lupinus angustifolius is the major grain legume grown on the acidic soils in Western Australia. However, L. luteus and L. albus are being researched as possible alternatives because of tolerance to diseases and specific soil type adaptation. The fertiliser phosphorus requirements of L. luteus and L. albus in acidic soils of Western Australia are not well known. By contrast, there is much information on the phosphorus requirements of L. angustifolius in these soils where placement of fertiliser phosphorus has been found to be important. Three field experiments were undertaken on different acidic soils in Western Australia (sand, sandy loam, and loamy sand) to compare how L. luteus cv. Teo and L. angustifolius cv. Merrit use fertiliser phosphorus, applied by different methods as superphosphate. Lupinus albus cv. Kiev Mutant, which is not adapted to the sandier soils, was included at the loamy sand site. In 2 experiments on the loamy soils, the phosphorus was either placed with the seed (drilled) or 8 cm below the seed while sowing seed at 5 cm (banded). In the experiment on sand, the phosphorus was either spread over the soil surface immediately in front of the seeding tines (topdressed) or banded below the seed. Compared with L. angustifolius: (i) for the 2 loamy soils, L. luteus used phosphorus more effectively for producing dried shoots, but was less effective at using phosphorus for producing seed (grain); (ii) for the loamy sand, L. albus was less effective at using the phosphorus for producing dried shoots and grain, except it was about equally effective for producing grain when the phosphorus was banded below the seed. For the sandy soil, L. luteus produced no grain yield response whereas L. angustifolius showed an about 20% yield response to the added phosphorus, and both methods of application were about equally effective. Phosphorus banded below the seed was more effective than phosphorus drilled with the seed for producing dried shoots and grain of L. albus on the loamy sand and for grain only of L. luteus on the sandy loam. Both methods of phosphorus application were about equally effective for producing dried shoots and grain of L. angustifolius and grain of L. luteus on the loamy sand. Fertiliser drilled with the seed was more effective than banded fertiliser for producing dried shoots and grain of L. angustifolius on the sandy loam and dried shoots of L. luteus on the loamy sand and sandy loam. The concentration of phosphorus in grain of L. luteus was consistently about double that found in grain of L. angustifolius. The concentration of manganese in dried shoots of L. albus was 3–5 times higher than in the other 2 species.

Maturity of Fresh-market Sweet Corn with Direct-seeded Plants, Transplants, Clear Plastic Mulch, and Rowcover Combinations

Sweet corn (Zea mays L.) growers in the upper midwestern U.S. have used clear plastic mulch to improve early yield and advance crop maturity. Results of this practice have been inconsistent because of early season temperature variability and inadequate information on cultivar adaptation. Our objective was to improve the performance consistency by investigating earliness techniques with the early, sugary-enhancer (se) cultivar Temptation planted at two sites. Treatments were bare soil or clear plastic mulch, rowcovers or none, and direct-seeded or transplanted plants. Transplants were produced in the greenhouse in either 50-cell plastic trays or peat pot strips, 2.3 inches × 4.0 inches deep (6 × 10 cm) and were evaluated according to transplant age and cell size. In the cold springs of 1996 and 1997, the use of clear plastic mulch shortened maturity of sweet corn by 1 and 10 days, respectively, for the silt loam site; but no maturity advantage was observed for the loamy sand site. Clear plastic raised the minimum soil temperature by 3.8 to 4.0 °F (2.1 to 2.2 °C) at both sites. The 2-week-old 50-cell tray transplants matured 6 days earlier than the peat pot strip transplants or direct seeded at both locations in 1997. Marketable yield from the transplants was inconsistent by location and year. Four-week-old transplants did not withstand field stress and performed poorly regardless of type of container. Ear quality as indicated by row number, ear diameter, ear length, and tipfill was lowest with transplants.

Transformation and retention of nitrogen in a coastal forest ecosystem

Transformations and fluxes of N were examined in three forested sites located along a gradient of soil texture in the coastal forests of the Waquoit Bay watershed on Cape Cod. Total N leaching losses to ground water were 0.5 kg ha-1 yr-1 in the loamy sand site and 1.5 kg ha-1 yr-1 in the fine sand site. Leaching loss to groundwater was not measured in the coarse sand site due to the prohibitive depth of the water table but total N leaching loss to 1m depth in the mineral soil was 3.9 kg ha-1 yr-1. DON accounted for most of the leaching losses below the rooting zone (77–89%) and through the soil profile to ground water (60%–80%). Differences in DON retention capacity of the mineral soil in the sites along the soil texture gradient were most likely related to changes in mineral soil particle surface area and percolation rates associated with soil texture. Forests of the watershed functioned as a sink for inorganic N deposited on the surface of the watershed in wet and dry deposition but a source of dissolved organic N to ground water and adjoining coastal ecosystems.

The influence of soil texture on the soil water dynamics and vegetation structure of a shortgrass steppe ecosystem

We analyzed soil water data from three sites with different soil textures in the shortgrass steppe of northeastern Colorado, USA. Our objective was to evaluate the relationship between the occurrence of plant functional types and the effect of soil texture on soil water availability. Soil water availability was greatest in the upper soil layers at all three sites, but the loamy sand site had significantly greater soil water availability than the sandy clay loam and sandy clay sites in wetter years at depths below 60 cm. Calculations of proportional water availability by layer using both field data and fifty-year soil water model simulations, showed that the sandy clay loam and sandy clay soils on average had greater water availability in layers 30 cm and above, but that the loamy sand had the greatest water availability in layers beneath this, particularly at 105 cm. This observation can be linked to the occurrence of a fine textured subsoil at this site. The textural pattern in the loamy sand profile effectively creates two water resources: a shallow pool accessible to all plants; and a deep pool accessible only to deep-rooted plants. This is offered as an explanation for the co-dominance of the two main plant functional types at the loamy sand site. At the other two sites, shallow-rooted shortgrass vegetation dominated, being more consistent with the general pattern for the area. Thus the patterns of vegetation structure at the three sites were consistent with the hypothesis. Aboveground net primary production data for the three sites, along with transpiration estimates from the model simulations, indicated that the additional water availability in the coarse textured soil was associated with higher overall plant productivity. Nomenclature: Taxonomic nomenclature follows R. L. McGregor & T. M. Barkley (1986) Flora of the Great Plains. Great Plains Flora Association. University Press of Kansas, Lawrence.

Foliar absorption of resuspended 137Cs relative to other pathways of plant contamination

The foliar absorption of 137Cs sorbed to suspended soil particles was quantified at two Ukranian locations contaminated by different forms of Chernobyl fallout. Our experimental design, allowed us to separate the pathways of foliar absorption, root uptake, and contamination adhering to plant surfaces. Foliar absorption, root uptake, and the quantity of soil-attached 137Cs adhering to leaves were greater at a loamy sand site contaminated with condensation-type fallout (Polesskoye), than at a sandy site contaminated with fuel-particles (Chistogolavka) (0.7 vs 0.04kBqkg −1; 20.8 vs 0.9kBqkg −1; and 3.2 vs 1.1mBqcm −2, respectively). We found that when 137Cs was very mobile in soils, root uptake grossly dominated all other plant contamination pathways. As the plant/soil concentration ratio decreased, a relative increase in foliar absorption from resuspension occurred, but it was quickly surpassed in importance by soil adhering to plant surfaces. The data suggest that although foliar absorption of 137Cs from suspended soil is measurable, it is inconsequential relative to other plant contamination pathways, and does not need to be considered as a critical pathway in routine radionuclide transport models.

Corn leaf water potential and water use efficiency under three conservation tillage systems

Corn ( Zea mays L.) was grown using three conservation tillage (CT) systems: till-plant (TP), chisel (CH) and no-till (NT), and conventional moldboard plow (CN) on two soils (silt loam and loamy sand). These tillage systems were compared for soil water storage capabilities, leaf water potential, dry matter and grain yield production per unit of water depleted. Soil water storage ranked NT > CH > TP > CN throughout the growing season in all profile segments for both soils with the exception of the 0.25–1-m zone in 1984 for the silt loam soil, where soil water storage ranked NT > CN > TP > CH. Greater water storage differences betweenthe CT systems and CN was found for deeper depths (> 0.75 m) in the loamy sand soil. Leaf water potential for both sites ranked NT > CH > TP > CN, indicating higher water stress for corn grown with CN compared to NT. In a relatively dry year such as 1983, the dry matter per unit of water depleted was 72.3, 64.3, 60.1 and 59.6 kg ha −1 mm −1 for CH, NT, TP and CN, respectively, for the silt loam site. Although no significant differences were detected, the dry matter production per unit of water depleted from NT was higher than CH, TP and CN by 1.1, 10.2 and 12.4%, respectively, in 1983 for the loamy sand site. Grain yield per unit of water depleted was not significantly different in all years and soil types with the exception of 1983 on the loamy sand soil where NT, CH and TP were higher than CN by 20.8, 12.9 and 14.6%, respectively. The greater amounts of water stored with the CT systems eliminated the potential for reduction in dry matter and grain yield with these systems due to lower soil temperature early in the growing season.

Atrazine Tolerance in Warm‐Season Grass Seedlings1

AbstractAtrazine [2‐chloro‐4‐(ethylamino)‐6‐(isopropylamino)‐s‐triazine] effectively controls many annual weeds in established warm‐season range grasses but can damage some of these grasses in the early seedling stage. This study determined the relative atrazine tolerance of seedlings of selected warm‐season grasses and evaluated the effectiveness of a greenhouse bioassay for seedling atrazine tolerance in range grasses. Seed of ‘Pathfinder’ switchgrass [Panicum virgatum L.], ‘Nebraska 54’ indiangrass [Sorghastrum nutans (L.) Nash], ‘Butte’ side‐oats grama [Bouteloua curtipedula (Michx.) Torr.], an experimental blue grama ‘PMK 1483’ [ B. gracilis (H.B.K.) Lag ex Steud], ‘Plains’ bluestem (Bothriochloa ischaemum var ischaemum (L.) Keng), ‘Caucasian’ bluestem [B. caucasica (Trin.) C.E. Hubbard] ‘Blaze’ little bluestem [Schizachyrium scoparium (Michx.) Nash], and a Nebraska experimental prairie sandreed [Calamovilfa longifolia (Hook) Scribn.] were planted in the greenhouse in a 1:1 soilsand mixture that contained 0,1,2, or 3 mg kg−1 atrazine. Seed lots from one cycle of field selection for atrazine tolerance of indiangrass and side‐oats grama were included. A field study was also conducted on a silty clay loam (Typic Argiudoll) and on a loamy sand (Udic Haplustoll) site using little bluestem, blue grama, prairie sandreed, Caucasian bluestem, and Plains bluestem. Survival ranking at 3 mg kg−1 atrazine, in the greenhouse, was: Caucasian bluestem = switchgrass > Plains bluestem > prairie sandreed > indiangrass (check) = indiangrass (cycle 1) > side‐oats grama (cycle 1) = side‐oats grama (check) = blue grama. Atrazine also reduced height in the surviving seedlings. Height reduction in did not appear to be related to seedling survival. Greenhouse data correlated closely with the loamy sand site. because the bioassay used a soil‐sand mixture. Excellent stands of Plains and Caucasian bluestem were obtained on the silty clay loam site at all atrazine rates. The bioassay was an effective screen to separate grasses with differing atrazine tolerances.

Vegetative Growth and Mortality of Drummond's Goldenweed (Isocoma drummondii [T. & G.] Greene: Compositae) as Influenced by Soil Moisture and Site Characteristics

Substantial emergence of Drummond's goldenweed (Isocoma Drummondii (T. & G.) Greene; Compositae) seedlings on the Texas Coastal Prairie occurred in 1 of the 2 yr study. Immediately following seed dispersal in January 1976, average density of new seedlings (2667/m2) on a grey sandy loam was nine times that of a tight sandy loam and almost 30 times that on a honey mesquite (Prosopis glandulosa Torr. var. glandulosa)-dominated loamy sand site. No new seedlings survived the spring season under natural conditions on any of the three sites, although seedling densities remained high in a fenced exclosure, especially where artificially seeded. Cumulative annual mortality of second-year seedlings was 100% on the loamy sand, 47% on the grey sandy loam, and 25% on the tight sandy loam site. Initial establishment of two populations of Drummond's goldenweed appear to have coincided with mechanical removal or serious disturbance of the mixed-brush overstory. Maximum rate of stem elongation (1.77 mm/day) of mature Drummond's goldenweed growing in full sunlight occurred during late summer and was associated with high rainfall. Stem growth of juvenile Drummond's goldenweed on a deep, calcareous site with high extractable phosphorus varied closely with soil water availability (r =0.85). On a heavier-textured, poorly-drained soil with a shallow argillic horizon where salts and sodium accumulated, stem growth was suppressed regardless of soil water availability. Average stem elongation rates of juvenile and mature Drummond's goldenweed across all sites and sampling dates were 0.49 and 0.77 mm/day, respectively. The perennial Drummond's goldenweed is a heavily-branched, suffrutescent subshrub. The rounded canopy may reach 1 m in height, 1 Approved by the Director, Texas Agricultural Experiment Station as TA 13887. Senior author was formerly a graduate research assistant, Texas Agricultural Experiment Station, College Station.