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Biosolids are used to improve soil physical and chemical properties. Analysis of biosolids-amended soils from multiple regions of United States using consistent analytical methods is lacking. This Study determined long-term biosolids application on soil pH, electrical conductivity (EC), carbon, cadmium, copper, lead, and zinc concentrations in soils from two regions in United States. At one region, little difference was observed in pH and EC between biosolids-amended surface soils and control, the second region ranged from 5.46 to 7.87 and 50.2 to 402 µS cm−1 respectively. Trace metal levels at this region ranged from 0.76 to 3.79, 8.7 to 54.1, 15.2 to 53.9, and 26 to 207 mg kg−1 for Cadmium, Copper, lead and Zinc respectively; with its carbon levels ranging from 14.5 to 90.0 g kg−1. Metal levels were within the standards for residential occupation with the 40 Code of Federal Regulations (CFR) Part 503 and should not affect soil and groundwater quality. [ABSTRACT FROM AUTHOR]

Current trends in agriculture have moved toward more sustainable cultivation systems with higher efficiency of input use. A variety of materials, derived from different resources, can serve as a crop nutrient sources. An Integrated Plant Nutrition System (IPNS) uses the combined and harmonious use of inorganic, organic and biological nutrient resources to maximize efficiency of inputs. We evaluated the effects of commercial nitrogen (N) fertilizer, humic acid compounds (HA), compost/manure teas and bioinoculants as inorganic, organic and biological resources, respectively and their synergy over three years on corn (Zea mays L.) in the Mid-Atlantic USA. The individual and combined application of HA and biofertilizer following the IPNS influenced corn height and leaf greenness to varying degrees, most likely due to biostimulant effects. In 2017, corn height, NDVI, greenness and vigor responded positively to biostimulant application to varying magnitudes and growth stages, however grain yield and nutrient content were not affected. In combined studies from 2018 and 2019 corn height was not impacted by biostimulant application but NDVI, photosynthetic efficiency, greenness and vigor were increased at different doses and corn growth stages. The combined use of HA + biofertilizer (Microlife Humic + Microgeo) was the only treatment leading to increased grain yield. This study demonstrates that the individual and combined application of HA and biofertilizer can influence corn growth and vigor at various points during the growing season. However, the current study cannot conclusively confirm that the integrated use of HA and biofertilizers (IPNS) is a better practice than the application of each compound individually. [ABSTRACT FROM AUTHOR]

Exceptional Quality (EQ) biosolids may be developed into products that can rehabilitate disturbed urban soils for the production of garden vegetables. The objectives of this study were to compare newly developed EQ biosolids products specially tailored for urban soil use with those of established products for the purpose of identifying their capability to support germination and plant growth, as well as to quantify their plant available nitrogen (N) and phosphorus (P). Seven EQ biosolids products and an inorganic fertilizer control were compared in greenhouse bioassays employing soybean (Glycine max L.) and tall fescue (Festuca arundinacea Schreb.) to assess product quality and nutrient availability. The EQ biosolids were derived from treatment processes such as thermal drying, composting, and blending with complementary organic and mineral materials. The EQ biosolids products applied at an estimated equivalent agronomic N rate enabled adequate germination and plant growth. The N uptake by tall fescue grown with the biosolids amendments compared with known rates of inorganic N confirmed organic N availability to be approximately 40%, 20%, and 15% for thermally dried, blended, and composted EQ biosolids products, respectively. The application of these products at agronomic N rates to a soil testing adequate in P increased soil P saturation to 20%-35%, a normal range for soil not excessively enriched with P. The availability of N and P in the EQ biosolids products will permit their agronomically beneficial and environmentally sound use in urban soils. [ABSTRACT FROM AUTHOR]

The amount of potentially mineralizable nitrogen (PMN) in early spring is critical to winter wheat production because maximum nitrogen (N) uptake begins then. We evaluated the Haney-Brinton CO2-burst method for quantifying PMN in early spring from biosolids fall-applied to soft red winter wheat (Triticum aestivum L.). Anaerobically digested and lime stabilized biosolids were fall-applied at 0, 50 and 100 kg PAN ha−1 at six locations in the Virginia Coastal Plain in 2013. The Haney-Brinton CO2-burst method did not provide an accurate estimation of spring PAN for biosolids applied in the fall for no-till winter wheat. The sum of preplant soil inorganic N and PMN of the unamended soil was better related to grain yield than PMN alone. The Haney-Brinton CO2-burst method is inadequate for use in no-till management but may provide an accurate mid-season estimate of winter wheat yield potential when used in combination with pre-plant soil inorganic N. [ABSTRACT FROM AUTHOR]

Urban land disturbance degrades physical, chemical, and biological soil properties by removing topsoil and compacting the remaining subsoil. Such practices create a soil environment that is unfavorable for vegetation establishment. A 3-year field study was conducted to compare the effects of various one-time compost application treatments on soil properties and re-vegetation of a disturbed soil. A disturbed urban soil received the following treatments: (1) inorganic fertilizer; (2) 2.5-cm-depth surface-applied compost; (3) 2.5-cm-depth incorporated compost; (4) 5.0-cm-depth incorporated compost; (5) inorganic fertilizer plus 0.6-cm compost blanket; and (6) inorganic fertilizer plus straw mat cover. The plots were seeded with a mixture of tall fescueFestuca arundinaceaShreb.: ‘Magellan,’ ‘Coronado Gold,’ ‘Regiment,’ and ‘Tomcat,’ perennial ryegrassLolium perenneL. ‘Linn’, and Kentucky bluegrassPoa pratenisL. ‘Baron.’ Soil chemical and physical attributes and plant growth and quality parameters were measured during 840 days following study establishment. Soil C, N, P, K, Ca, and Mg, and turfgrass growth and quality were increased and soil bulk density was reduced by amending with composts. Incorporation of compost into soil improved soil and plant attributes more than unincorporated surface application, but the differences diminished with time. Compost benefits increased with time. One-time applications of compost can provide immediate and long-term benefits to soil and plant attributes, but there may be no need to incorporate the compost into soil, particularly if the soil has recently been loosened by tillage. [ABSTRACT FROM AUTHOR]

Inadequate nutrients and poor soil quality pose challenges for turfgrass establishment on disturbed soils. Compost amendment has been shown to mitigate poor soil quality. This research was conducted to compare surface applications of compost to standard hydroseeding for improving soil chemical properties and turfgrass establishment. Plots established with either hydroseed or compost in spring 2007 were evaluated for soil pH, Mehlich-I extractable K, Mg, Zn, P, total N, organic C, and percent ground cover, fescue coverage and biomass production of tall (Festuca arundinacea Schreb.) and chewing's fescue [Festuca rubra L. ssp.fallax (Thuill.) Nyman ]. Two years after plot establishment, the compost treatment had significantly increased Mehlich-I extractable soil P, K and Zn. Phosphorus increased 566% in the compost soil but only 17% in the hydroseeded soil. Higher percentages of ground coverage were reported in the compost than the hydroseed treatments with coverage in treatments declining from 2008 to 2009. Although the surface additions of compost initially enhanced the establishment and growth of fescue, vegetation may be limited in the long run by soil conditions in the root zone and competing broadleaf weeds. [ABSTRACT FROM AUTHOR]

Field research was conducted to assess the effects of organic and inorganic soil amendments on soil humiffed carbon content and plant physiological properties. Long term applications of various types and rates of compost, poultry litter and inorganic fertilizer were assessed for their effects on corn [Zea mays (L.) Pioneer 31G20] and soybean [Glycine max (1.) Delta Pine 4933RR] grown in a Virginia (United States) Piedmont soil in 2004 and 2005. Treatment differences in leaf antioxidant activity were only observed in the corn plots. Corn fertilized with amendments supplying the crop's nitrogen needs, regardless of the source, had greater leaf nitrogen (+29%), chlorophyll (+33%), and protein contents (+37%), lower superoxide dismutase (-29%) and ascorbate peroxidase (-17%) activities, and lower malondialdehyde (-33%) contents than the control and low nitrogen treatments. Yield was strongly related to midseason leaf nitrogen contents (R²=0.87, p<0.0001) and not with soil humified carbon (R²=0.02, p=0.0543). Soybean grown in the organically amended soil had higher yields (9-21% increase), protein contents (4-9% increase) and seed weights (5-14% increase) than the inorganically fertilized and unfertilized treatments. Improvements in soybean yield and seed quality were due to organic amendment benefits other than plant available water or nutrient supply. [ABSTRACT FROM AUTHOR]

Presents a study on the potential for composting the Virginia Fibre Corporation's combined primary and secondary dewatered paper mill sludge. Evaluation of the suitability of the finished product as a potting soil medium; Methodology of the study; Results and discussion; Conclusions.

Understanding seasonal soil mineral nitrogen (N) dynamics under various cover cropping systems will aid in making supplemental fertilizer N recommendations for corn (Zea mays L.) using soil nitrate testing. A split‐plot field study was conducted to track early season soil mineral N under corn grown after cover crops and to determine the usefulness of the pre‐sidedress soil nitrate test (PSNT) in cover crop‐corn systems. The cover crop treatments rye (Secale cereale L.), hairy vetch (Vicia villosa Roth), rye+hairy vetch, and fallow were established as main plots to provide a range of soil N availability for a subsequent corn crop. The split plot treatment was sidedress fertilizer N rate, which consisted of six rates ranging from 0–250 kg N ha‐1 in 50 kg increments. Soil was sampled throughout the growing season and corn was sampled at Hanway's corn growth stage 5 in the 0 kg N ha‐1 check plots to assess periodic soil N availability. Soil N concentrations peaked between Hanway's corn growth stage 1 and 3 and were concentrated in the top 15 cm of the soil. Vetch and fallow treatments provided higher amounts of available N as indicated by soil and corn N concentrations and corn yields. Recommended PSNT sampling times resulted in critical soil [NO3‐N] values that are similar to those used for PSNT fertilization; however, sampling to a depth of 15 cm may be adequate when a considerable portion of plant available N is supplied by cover crops. Addition of NH4‐N to NO3‐N testing did not improve the predictive capability of the soil test for supplemental corn N needs. The time of sampling may be delayed as much as two weeks without a loss of prediction accuracy. [ABSTRACT FROM PUBLISHER]

Potential contributions several mulches to soil organic matter (OM), and their effects on crop-available nitrogen (N), earthworm activity and tilth-related soil properties, were evaluated on five working vegetable farms in Virginia. A 100-mm thick hay mulch added sufficient organic carbon (C) and N to replace seasonal soil OM losses expected for temperate zone soils. Paper and plastic mulches contributed little or no OM, but mulching alleys between film-mulched beds helped replenish soil OM in these mulching systems. At one site, soil NO3-N was higher under plastic and oiled-paper mulches than under organic mulches or without mulch, probably because plastic and oiled paper reduced leaching of NO3-N. Mulch treatment did not affect soil NO3-N at other sites, and generally did not affect tomato foliar TKN, except when the treatment reduced soil moisture levels. Hay and compost mulches had C:N ratios ranging from 24 to 48, but high foliar TKN in these treatments indicated that the mulches did not reduce N availability to the crop. Mulch treatments imposed for a single growing season did not affect soil bulk density, steady state water infiltration rate or wet aggregate stability. However, earthworm populations at the end of the season were about twice as high under hay mulch as under black plastic. [ABSTRACT FROM PUBLISHER]

The effects of hay, compost, plastic and paper mulches on soil temperature, soil moisture and yield of paste tomato were evaluated on five farms in Virginia. Organic mulches reduced afternoon soil temperature and maintained higher soil moisture levels than other treatments. Black plastic mulch increased soil temperatures by 1–2°C, but sometimes resulted in lower soil moisture levels in early summer, probably by hindering penetration of rainfall. Both undyed kraft paper and black paper mulches reduced afternoon soil temperature slightly. Oiled paper initially increased afternoon soil temperature by 4°C, but this effect diminished over time. Paper mulches decomposed before the end of the season, allowing increased evaporative losses of soil moisture. Mulch treatments apparently affected early tomato yield by influencing soil temperature regime, but affected later yields by modifying soil moisture levels. Early yields were generally highest with black plastic mulch and lowest in organic mulches, with paper mulch intermediate. At sites not affected by late blight, total yields were generally: organic mulch ≥ plastic ≥ paper > unmulched. At sites affected by late blight, later-maturing fruit were lost, so that the delay in ripening in soil-cooling organic mulches resulted in a significant yield reduction compared to black plastic. [ABSTRACT FROM PUBLISHER]

The presidedress soil nitrate test (PSNT) and the presidedress tissue nitrogen test (PTNT) have been developed to assess residual soil nitrogen (N) sufficiency for corn (Zea mays L.) in the humid eastern U.S. We conducted field studies at 47 sites during 1990 and 1991 to evaluate the use of the PSNT and PTNT for corn in Coastal Plain, Piedmont, and Appalachian Ridge and Valley regions of Virginia. Seven rates of fertilizer N (0, 45, 90, 135, 180, 225, and 270 kg/ha) were applied at corn height of 0.40 to 0.50 m and replicated four times in a randomized complete block design. Whole corn plants and soil to a depth of 0.30 m were sampled when corn height was 0.15 to 0.30 m to estimate available soil N prior to the application of fertilizer N treatments. Corn grain yield response to fertilizer N was used to assess residual soil N availability. Nitrogen concentration of whole corn plants at 0.15 to 0.30 m height was not an accurate indicator of plant‐available soil N. Corn yields were maximized without sidedress N at the 19 sites where soil NO3‐N was at least 18 mg‐kg‐1 and at the 17 sites where soil (NO3+NH4)‐N was at least 22 mg‐kg‐1. The PSNT predicted corn N sufficiency regardless of soil physiographic region or surface texture; however, the critical values for NO3‐N and (NO3+NH4)‐N were 3 to 5 mg‐kg‐1 lower than those established in Pennsylvania and Maryland, where cooler soil temperatures may permit greater residence time of inorganic N. [ABSTRACT FROM PUBLISHER]