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Greenhouse gas (GHG) emissions from crop residue management have been studied extensively, yet the effects of harvesting more than one crop residue in a rotation have not been reported. Here, we measured the short-term changes in methane (CH4), nitrous oxide (N2O), and carbon dioxide (CO2) emissions in response to residue removal from continuous corn (Zea mays L.) (CC) and corn–wheat (Triticum aestivum L.)–soybean (Glycine max L. Merr.) (CWS) rotations in the Mid-Atlantic USA. A first experiment retained five corn stover rates (0, 3.33, 6.66, 10, and 20 Mg ha−1) in a continuous corn (CC) in Blacksburg, VA, in 2016 and 2017. Two other experiments, initiated during the wheat and corn phases of the CWS rotation in New Kent, VA, utilized a factorial combination of retained corn (0, 3.33, 6.66, and 10.0 Mg ha−1) and wheat residue (0, 1, 2, and 3 Mg ha−1). Soybean residue was not varied. Different crop retention rates did not affect CO2 fluxes in any of the field studies. In Blacksburg, retaining 5 Mg ha−1 stover or more increased CH4 and N2O emissions by ~25%. Maximum CH4 and N2O fluxes (4.16 and 5.94 mg m−2 day−1) occurred with 200% (20 Mg ha−1) retention. Two cycles of stover management in Blacksburg, and one cycle of corn or wheat residue management in New Kent did not affect GHG fluxes. This study is the first to investigate the effects of crop residue on GHG emissions in a multi-crop system in humid temperate zones. Longer-term studies are warranted to understand crop residue management effects on GHG emissions in these systems.

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 mu S 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.

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.

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.

Background Human wastewater biosolids, hereafter referred to as biosolids, are produced in significant quantities around the world and often applied to an extensive land mass including agricultural fields, forests, mine lands, and urban areas. Land-application of biosolids has been reported in peer-reviewed and non-peer-reviewed work to change soil organic carbon stocks in varying amounts. Determining the potential of soil organic carbon (SOC) stock change and sequestration from biosolids land application is critical for biosolids producers and users to gain access to carbon credit markets. Our review question is, "what is the impact of biosolids application on long-term soil carbon sequestration rates?” We look to explore this main question with the follow-up, "does biosolids processing methods and characteristics, application method, soil properties, land management and other modifiers affect rates of carbon accumulation from land-applied biosolids?" Methods Searches will be conducted using online databases (i.e., Web of Science Core Collection, CAB Abstracts, Scopus, ProQuest Dissertations & Theses Global), search engines (Google Scholar and Microsoft Academic), and specialist websites to find primary field studies and grey literature of biosolids land-application effects on soil organic carbon stocks. We will use English search terms and predefined inclusion criteria of: (1) a field study of at least 24 months that reports soil organic carbon/matter (SOC/SOM) concentrations/stocks; (2) has two types of treatments: (i) a control (non-intervention AND/OR synthetic fertilizer) AND (ii) a biosolids-based amendment; and (3) information of amendment properties and application dates and rates to estimate the relative contribution of the applied materials to SOC changes. We will screen results in two stages: (1) title and abstract and (2) full text. A 10% subset will be screened by two reviewers for inclusion at the title and abstract level and use a kappa analysis to e

The illegal status of cannabis (Cannabis sativa L.) post-World War II resulted in a lack of research on agricultural practices. However, there is a resurgence of interest in cannabis due to diverse uses such as a rich source of cellulosic/woody fiber and construction uses, seed oil, bioenergy and pharmaceutical properties. The principle of an integrated plant nutrition system (IPNS) is to enable adaptation of plant nutrition and soil fertility management to local site characteristics, attempting to optimize use of inorganic, organic and biological resources. This project investigated the individual and combined use of inorganic, organic and biological fertilizer resources on cannabis before and after a period of moderate water stress. We evaluated the individual and combined effects of commercial synthetic fertilizer, humic acid (HA), manure tea and bioinoculant as inorganic, organic and biological resources, respectively on cannabis growth and physiological parameters. Our hypothesis was that the synergetic effects of HA + biofertilizers would improve cannabis growth. When compared to the control, the application of HA and biofertilizer alone, or in combination, increased plant height, chlorophyll content and photosynthetic efficiency by 55, 8 and 12%, respectively, after water stress. Cannabis biomass of treated plants was rarely different from the control. The combined application of HA + biofertilizer resulted in additive, but not synergistic, increases in measured parameter. Future research should focus on the effects of biostimulants on CBD/THC content due to the potential impact on the production of secondary metabolites in plants under stress.

The illegal status of cannabis (Cannabis sativa L.) post-World War II resulted in a lack of research on agricultural practices. However, there is a resurgence of interest in cannabis due to diverse uses such as a rich source of cellulosic/woody fiber and construction uses, seed oil, bioenergy and pharmaceutical properties. The principle of an integrated plant nutrition system (IPNS) is to enable adaptation of plant nutrition and soil fertility management to local site characteristics, attempting to optimize use of inorganic, organic and biological resources. This project investigated the individual and combined use of inorganic, organic and biological fertilizer resources on cannabis before and after a period of moderate water stress. We evaluated the individual and combined effects of commercial synthetic fertilizer, humic acid (HA), manure tea and bioinoculant as inorganic, organic and biological resources, respectively on cannabis growth and physiological parameters. Our hypothesis was that the synergetic effects of HA + biofertilizers would improve cannabis growth. When compared to the control, the application of HA and biofertilizer alone, or in combination, increased plant height, chlorophyll content and photosynthetic efficiency by 55, 8 and 12%, respectively, after water stress. Cannabis biomass of treated plants was rarely different from the control. The combined application of HA + biofertilizer resulted in additive, but not synergistic, increases in measured parameter. Future research should focus on the effects of biostimulants on CBD/THC content due to the potential impact on the production of secondary metabolites in plants under stress.

Spectral reflectance measurements collected from hyperspectral and multispectral radiometers have the potential to be a management tool for detecting water and nutrient stress in turfgrass. Hyperspectral radiometers collect hundreds of narrowband reflectance data compared to multispectral radiometers that collect three to ten broadband reflectance data for a cheaper cost. Spectral reflectance data have been used to create vegetation indices such as the normalized difference vegetation index (NDVI) and the simple ratio vegetation index (RVI) to assess crop growth, density, and fertility. Other indices such as the water band index (WBI) (narrowband index) and green-to-red ratio index (GRI) (both broadband and narrowband index) have been proposed to predict soil moisture status in turfgrass systems. The objective of this study was to compare the value of multispectral and hyperspectral radiometers to assess soil volumetric water content (VWC) and tall fescue (Festuca arundinacea Schreb.) responses. The multispectral radiometer VI had the strongest relationships to turfgrass quality, biomass, and tissue N accumulation during the trial period (April 2017–August 2018). Soil VWC had the strongest relationship to WBI (r = 0.60), followed by GRI and NDVI (both r = 0.54) for the 0% evapotranspiration (ET). Nonlinear regression showed strong relationships at high water stress periods in each year for WBI (r = 0.69–0.79), GRI (r = 0.64–0.75), and NDVI (r = 0.58–0.79). Broadband index data collected using a mobile multispectral sensor is a cheaper alternative to hyperspectral radiometry and can provide better spatial coverage.

Spectral reflectance measurements collected from hyperspectral and multispectral radiometers have the potential to be a management tool for detecting water and nutrient stress in turfgrass. Hyperspectral radiometers collect hundreds of narrowband reflectance data compared to multispectral radiometers that collect three to ten broadband reflectance data for a cheaper cost. Spectral reflectance data have been used to create vegetation indices such as the normalized difference vegetation index (NDVI) and the simple ratio vegetation index (RVI) to assess crop growth, density, and fertility. Other indices such as the water band index (WBI) (narrowband index) and green-to-red ratio index (GRI) (both broadband and narrowband index) have been proposed to predict soil moisture status in turfgrass systems. The objective of this study was to compare the value of multispectral and hyperspectral radiometers to assess soil volumetric water content (VWC) and tall fescue (Festuca arundinacea Schreb.) responses. The multispectral radiometer VI had the strongest relationships to turfgrass quality, biomass, and tissue N accumulation during the trial period (April 2017–August 2018). Soil VWC had the strongest relationship to WBI (r = 0.60), followed by GRI and NDVI (both r = 0.54) for the 0% evapotranspiration (ET). Nonlinear regression showed strong relationships at high water stress periods in each year for WBI (r = 0.69–0.79), GRI (r = 0.64–0.75), and NDVI (r = 0.58–0.79). Broadband index data collected using a mobile multispectral sensor is a cheaper alternative to hyperspectral radiometry and can provide better spatial coverage.

Provides a detailed explanation of what compost is and is not, and also provides information about the benefits of compost for soil and plant improvements.

This document is a directory of compost producers and suppliers in the Mid-Atlantic Region.

Bioretention cells are engineered systems used in urban areas as stormwater treatment to remove unwanted nutrients from runoff. The objectives of the paper are to examine existing studies to determine effects of media composition, media depth, specific species of plants, and temperature on the removal/immobilization of nitrogen (N) and phosphorus (P) in bioretention cells. After reviewing studies performed to date, a number of conclusions can be reached regarding recommendations for bioretention cells to remove N and P. More times than not, N is removed through nitrification-denitrification within the media, and P is removed through sorption. Multiple studies investigating the appropriate media textures concluded that a sandy loam or sandy soil with the addition of at least 3% water treatment residuals (WTR) should be used in bioretention cells to help with removal of P. A specific organic matter (OM) recommendation could not be determined, but a positive correlation with NH4 removal supports the Virginia Department of Conservation and Recreation guidelines of 3-5% addition of OM. N removal was higher when a saturated zone plus organic matter was used versus an unsaturated cell zone without organic matter. The pH of the bioretention cell should be between 6 and 7. The suggested media depth should be 50 to 90 cm. Certain species perform better with respect to nutrient removal efficiencies, and it is recommended that Carex spp. be utilized when possible. Nitrogen removal is higher when both vegetation and a saturated zone are present in a bioretention cell. Native species are convenient for cell maintenance purposes, but not all native species help remove N and P more efficiently. Although temperature does have an effect on nitrification-denitrification and P sorption through slowing infiltrations rates because of frozen soil, the results show that overall performance of the bioretention cell is not negatively affected., Bioretention cells are engineered systems used in urban areas as stormwater treatment to remove unwanted nutrients from runoff. The objectives of the paper are to examine existing studies to determine effects of media composition, media depth, specific species of plants, and temperature on the removal/immobilization of nitrogen (N) and phosphorus (P) in bioretention cells. After reviewing studies performed to date, a number of conclusions can be reached regarding recommendations for bioretention cells to remove N and P. More times than not, N is removed through nitrification-denitrification within the media, and P is removed through sorption. Multiple studies investigating the appropriate media textures concluded that a sandy loam or sandy soil with the addition of at least 3% water treatment residuals (WTR) should be used in bioretention cells to help with removal of P. A specific organic matter (OM) recommendation could not be determined, but a positive correlation with NH4 removal supports the Virginia Department of Conservation and Recreation guidelines of 3-5% addition of OM. N removal was higher when a saturated zone plus organic matter was used versus an unsaturated cell zone without organic matter. The pH of the bioretention cell should be between 6 and 7. The suggested media depth should be 50 to 90 cm. Certain species perform better with respect to nutrient removal efficiencies, and it is recommended that Carex spp. be utilized when possible. Nitrogen removal is higher when both vegetation and a saturated zone are present in a bioretention cell. Native species are convenient for cell maintenance purposes, but not all native species help remove N and P more efficiently. Although temperature does have an effect on nitrification-denitrification and P sorption through slowing infiltrations rates because of frozen soil, the results show that overall performance of the bioretention cell is not negatively affected.

This handbook is a revision and update of a nutrient management training manual for Chesapeake Bay watershed published in 2000. This handbook includes the latest information on managing soils, crops and nutrients in order to better protect surface and ground water in the Mid-Atlantic region.