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21 pages, 1431 KiB

Open AccessArticle

Assessment of the Carbon and Nitrogen Mineralisation of Digestates Elaborated from Distinct Feedstock Profiles

by Gregory Reuland, Ivona Sigurnjak, Harmen Dekker, Steven Sleutel and Erik Meers

Agronomy 2022, 12(2), 456; https://doi.org/10.3390/agronomy12020456 - 11 Feb 2022

Cited by 16 | Viewed by 4702

Abstract

The carbon (C) and nitrogen (N) mineralisation rates of five digestates were studied and compared with pig slurry, compost, and a solid fraction of digestate in aerobic incubation experiments. The objective was to identify the most relevant drivers of C and N mineralisation [...] Read more.

The carbon (C) and nitrogen (N) mineralisation rates of five digestates were studied and compared with pig slurry, compost, and a solid fraction of digestate in aerobic incubation experiments. The objective was to identify the most relevant drivers of C and N mineralisation based on the physicochemical properties of the products. Net organic nitrogen mineralisation of digestates (N_min,net) was on average 30%, although the range was relatively wide, with digestate from pig manure (39%) reaching double the value of digestate from sewage sludge (21%). The total carbon to total nitrogen (TC:TN) (r = −0.83, p < 0.05) and ammonium nitrogen to total nitrogen (NH₄⁺-N:TN) (r = 0.83, p < 0.05) ratios of the products were strongly correlated with N_min,net, adequately mirroring the expected fertilising potential of the products. The digestates had C sequestration values between 50 and 81% of applied total organic carbon (TOC), showcasing their potential to contribute to C build-up in agricultural soils. The carbon use efficiency of the amended soils was negatively correlated with dissolved organic carbon (DOC) (r = −0.75, p < 0.05) suggesting that catabolic activities were promoted proportionately to the DOC present in these products. Ratios of DOC:TOC (r = −0.88, p < 0.01) and TC:TN (r = 0.92, p < 0.01) were reliable predictors of the fraction of C that would remain one year after its incorporation and thus could be used as simple quality parameters to denote the C sequestration potential of digestates prior to their use in the field. Full article

(This article belongs to the Special Issue Recycling Agricultural, Industrial, and Municipal Byproducts While Enhancing Agricultural Production and Protecting the Environment – Volume I)

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19 pages, 7859 KiB

Open AccessArticle

Determination of the Composition of Bio-Oils from the Pyrolysis of Orange Waste and Orange Pruning and Use of Biochars for the Removal of Sulphur from Waste Cooking Oils

by Francisco-José Sánchez-Borrego, Noelia García-Criado, Juan F. García-Martín and Paloma Álvarez-Mateos

Agronomy 2022, 12(2), 309; https://doi.org/10.3390/agronomy12020309 - 25 Jan 2022

Cited by 5 | Viewed by 3073

Abstract

Waste generated in the agri-food sector is a potential source of biomass and other products of high added value. In this work, the pyrolysis of orange waste and orange pruning was carried out to produce adsorbent biochars and characterise the bio-oils aiming for [...] Read more.

Waste generated in the agri-food sector is a potential source of biomass and other products of high added value. In this work, the pyrolysis of orange waste and orange pruning was carried out to produce adsorbent biochars and characterise the bio-oils aiming for high-added-value compounds. Pyrolysis was carried out in a vertical tubular furnace on the laboratory scale modifying the temperature (400–600 °C), the heating ramp (5–20 °C·min⁻¹) to reach the previous temperature and the inert gas flow rate (30–300 mL Ar·min⁻¹) throughout the furnace. The most suitable conditions for obtaining biochar were found to be 400 °C, 5 °C·min⁻¹, and 150 mL Ar·min⁻¹ for orange waste, and 400 °C, 10 °C·min⁻¹, and 150 mL Ar·min⁻¹ for orange pruning. Thermogravimetric analysis showed higher thermal stability for orange pruning due to its higher lignin content (20% vs. 5% wt. on a wet basis). The bio-oil composition was determined by GC-MS. Toluene and 5-hydroxymethylfurfural were the main compounds found in orange waste bio-oils, while orange pruning bio-oils were composed mainly of 4-hydroxy-4-methyl-2-pentanone. Finally, the removal of the sulphur content from waste cooking oil was assayed with the biochars from both orange waste and orange pruning, whose BET surface areas were previously determined. Despite their low specific surface areas (≤1 m²·g⁻¹ for orange waste biochars and up to 24.3 m²·g⁻¹ for orange pruning biochars), these biochars achieved a reduction of the initial sulphur content of the waste cooking oil between 66.4% and 78.8%. Full article

(This article belongs to the Special Issue Recycling Agricultural, Industrial, and Municipal Byproducts While Enhancing Agricultural Production and Protecting the Environment – Volume I)

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15 pages, 1514 KiB

Open AccessArticle

Spectroscopic and Physicochemical Characterization of Poultry Waste-Based Composts and Charcoal–Compost Mixtures for the Prediction of Dry Matter Yield of Giant of Italy Parsley

by Francielly T. Santos, Mônica S. S. M. Costa, Luiz A. M. Costa, Henrique Trindade, Larissa M. S. Tonial, Higor E. F. Lorin and Piebiep Goufo

Agronomy 2022, 12(2), 256; https://doi.org/10.3390/agronomy12020256 - 20 Jan 2022

Cited by 3 | Viewed by 2451

Abstract

Plant growing substrates obtained by composting agro-industrial waste can serve as organic soil amendments. However, it is crucial to determine the maturity and quality of organic amendments before their application to soil. This study aimed to evaluate the suitability of compost obtained from [...] Read more.

Plant growing substrates obtained by composting agro-industrial waste can serve as organic soil amendments. However, it is crucial to determine the maturity and quality of organic amendments before their application to soil. This study aimed to evaluate the suitability of compost obtained from poultry wastes combined with five different vegetal residues (tree trimmings, sugarcane bagasse, sawdust, cotton residues, and Napier grass) as growth media for container-grown Giant of Italy parsley. Fourier-transform infrared and laser-induced fluorescence spectra were used to characterize the humification extent in composts before and after the addition of charcoal at five inclusion rates (0%, 15%, 30%, 45%, and 60%, weight basis). Spectroscopic measurements identified absorption bands between 1625 and 1448 cm⁻¹ specific to each of the 25 organic amendments evaluated. The most suitable amendments (composts made from sawdust and sugarcane bagasse) were associated with O–H stretching of phenols and aromatic rings. Charcoal addition to composts changed some of their physical characteristics, leading to increased nutrient availability in some cases. Experimental and calculated dry matter yield were compared via multiple linear regression and simple non-linear regression as a function of the spectroscopic and physicochemical (N, P, K, pH, EC, C, H_LIF, C:N, CEC, HA:HA) properties of the organic amendments. Regression models accurately assigned high yields to the sawdust- and bagasse-based composts and low yields to the Napier grass- and cotton-based composts. Electrical conductivity (EC) was the main factor limiting potted-parsley productivity, an indication that efficient management of charcoal rate and compost EC levels can aid in predicting parsley yield. Full article

(This article belongs to the Special Issue Recycling Agricultural, Industrial, and Municipal Byproducts While Enhancing Agricultural Production and Protecting the Environment – Volume I)

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12 pages, 290 KiB

Open AccessArticle

Identification of Microbial Populations in Blends of Worm Castings or Sugarcane Filter Mud Compost with Biochar

by Maureen S. Wright and Isabel M. Lima

Agronomy 2021, 11(8), 1671; https://doi.org/10.3390/agronomy11081671 - 22 Aug 2021

Cited by 4 | Viewed by 3360

Abstract

Soil amendments are used to improve soil quality, thereby enhancing plant growth and health. Efforts have been made to replace synthetic chemical enhancers. It is also preferable to not use natural products such as peat moss, the harvesting of which can be harmful [...] Read more.

Soil amendments are used to improve soil quality, thereby enhancing plant growth and health. Efforts have been made to replace synthetic chemical enhancers. It is also preferable to not use natural products such as peat moss, the harvesting of which can be harmful to marine ecosystems. Viable replacements include worm castings, which can contribute beneficial microbes, as well as physicochemical amendments. Another potential soil amendment is the compost produced from sugarcane processing byproducts. While the texture of these two materials is not ideal for even dispersal onto fields, the addition of biochar improves the texture. Previous work demonstrated that blending them with biochar from sugarcane byproducts added physicochemical benefits, while not quantitatively reducing the microbial load, even after storage. Microbial populations of the blends in the present study were found to (1) contain taxonomic groups that contribute to plant health and (2) not contain human pathogens. Based on the quantitative and qualitative microbial analyses, it has been determined that 50% or less biochar in a blend will allow maintenance of beneficial microbes in stored samples. Full article

(This article belongs to the Special Issue Recycling Agricultural, Industrial, and Municipal Byproducts While Enhancing Agricultural Production and Protecting the Environment – Volume I)

13 pages, 7867 KiB

Open AccessArticle

Pilot-Scale H₂S and Swine Odor Removal System Using Commercially Available Biochar

by Kyoung S. Ro, Bryan Woodbury, Mindy Spiehs, Ariel A. Szogi, Philip J. Silva, Okhwa Hwang and Sungback Cho

Agronomy 2021, 11(8), 1611; https://doi.org/10.3390/agronomy11081611 - 13 Aug 2021

Cited by 7 | Viewed by 3335

Abstract

Although biochars made in laboratory seem to remove H₂S and odorous compounds effectively, very few studies are available for commercial biochars. This study evaluated the efficacy of a commercial biochar (CBC) for removing H₂S and odorous volatile organic compounds [...] Read more.

Although biochars made in laboratory seem to remove H₂S and odorous compounds effectively, very few studies are available for commercial biochars. This study evaluated the efficacy of a commercial biochar (CBC) for removing H₂S and odorous volatile organic compounds (VOCs). We found that the well-known Ergun equation may not be adequate in predicting pressure drop for properly sizing a ventilation system. The H₂S breakthrough adsorption capacity of the CBC was 2.51 mg/g under humid conditions, which was much higher than that for dry conditions. The breakthrough capacity increased with the influent concentration of H₂S. The efficacy of a pilot-scale biochar odor removal system (PSBORS) for removing 15 odorous VOCs was evaluated by placing it in a swine gestation stall continually treating the inside air for 21 days. All VOCs in the PSBORS effluent were below detection limit except for acetic acid. However, due to the very high odor threshold of acetic acid, its contribution to the odor would be minimal. It appeared that the CBC could be used to reduce both H₂S and odorous VOCs with the potential of recycling the spent CBC for soil health improvement after using it for H₂S and odor removal. Full article

(This article belongs to the Special Issue Recycling Agricultural, Industrial, and Municipal Byproducts While Enhancing Agricultural Production and Protecting the Environment – Volume I)

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14 pages, 1070 KiB

Open AccessArticle

Producing Superphosphate with Sewage Sludge Ash: Assessment of Phosphorus Availability and Potential Toxic Element Contamination

by Yawen You, Jakob Klein, Tobias Edward Hartmann, Peteh Mehdi Nkebiwe, Huaiyu Yang, Wei Zhang, Xinping Chen and Torsten Müller

Agronomy 2021, 11(8), 1506; https://doi.org/10.3390/agronomy11081506 - 29 Jul 2021

Cited by 7 | Viewed by 2907

Abstract

Recovering and recycling phosphorus (P) from sewage sludge ash (SSA) for the purpose of P fertilizer production contributes to reducing the input of mined phosphate-minerals and closing of the P cycle. However, direct use of SSA as fertilizer is often a questionable strategy [...] Read more.

Recovering and recycling phosphorus (P) from sewage sludge ash (SSA) for the purpose of P fertilizer production contributes to reducing the input of mined phosphate-minerals and closing of the P cycle. However, direct use of SSA as fertilizer is often a questionable strategy due to its low nutrient use efficiency. In addition, the environmental risk potential of utilizing SSA in agriculture is still unclear, in particular potential toxic element (PTE) contamination. In this study, a mixture of SSA and rock phosphate was used at lab-scale superphosphate (SP) production. P availability of the final product and PTE contamination (Cd, Cr, Cu, Zn, Pb, Ni) in soil and crop was investigated through maize (Zea mays L.) cultivation. Results showed that the application of SP that was produced by 25% SSA replacement did not affect the growth, P uptake, and PTE content in aboveground maize compared to the application of SP produced without SSA replacement. However, significant inputs of SP with SSA replacement may decrease the solid-soil solution partitioning of Cu, Ni and Pb in the long-term. Separation of municipal/industrial sludge and PTE removal technology are necessary to be implemented prior to the use of SSA as a secondary raw material in P-fertilizer production. Full article

(This article belongs to the Special Issue Recycling Agricultural, Industrial, and Municipal Byproducts While Enhancing Agricultural Production and Protecting the Environment – Volume I)

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24 pages, 5300 KiB

Open AccessArticle

Biosolids Benefit Yield and Nitrogen Uptake in Winter Cereals without Excess Risk of N Leaching

by Silvia Pampana, Alessandro Rossi and Iduna Arduini

Agronomy 2021, 11(8), 1482; https://doi.org/10.3390/agronomy11081482 - 26 Jul 2021

Cited by 6 | Viewed by 2321

Abstract

Winter cereals are excellent candidates for biosolid application because their nitrogen (N) requirement is high, they are broadly cultivated, and their deep root system efficiently takes up mineral N. However, potential N leaching from BS application can occur in Mediterranean soils. A two-year [...] Read more.

Winter cereals are excellent candidates for biosolid application because their nitrogen (N) requirement is high, they are broadly cultivated, and their deep root system efficiently takes up mineral N. However, potential N leaching from BS application can occur in Mediterranean soils. A two-year study was conducted to determine how biosolids affect biomass and grain yield as well as N uptake and N leaching in barley (Hordeum vulgare L.), common wheat (Triticum aestivum L.), durum wheat (Triticum turgidum L. var. durum), and oat (Avena byzantina C. Koch). Cereals were fertilized at rates of 5, 10, and 15 Mg ha⁻¹ dry weight (called B5, B10, and B15, respectively) of biosolids (BS). Mineral-fertilized (MF) and unfertilized (C) controls were included. Overall, results highlight that BS are valuable fertilizers for winter cereals as these showed higher yields with BS as compared to control. Nevertheless, whether 5 Mg ha⁻¹ of biosolids could replace mineral fertilization still depended on the particular cereal due to the different yield physiology of the crops. Moreover, nitrate leaching from B5 was comparable to MF, and B15 increased the risk by less than 30 N-NO₃ kg ha⁻¹. We therefore concluded that with specific rate settings, biosolid application can sustain yields of winter cereals without significant additional N leaching as compared to MF. Full article

(This article belongs to the Special Issue Recycling Agricultural, Industrial, and Municipal Byproducts While Enhancing Agricultural Production and Protecting the Environment – Volume I)

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16 pages, 1282 KiB

Open AccessArticle

Agro-Industrial and Urban Compost as an Alternative of Inorganic Fertilizers in Traditional Rainfed Olive Grove under Mediterranean Conditions

by Laura L. de Sosa, Emilio Benítez, Ignacio Girón and Engracia Madejón

Agronomy 2021, 11(6), 1223; https://doi.org/10.3390/agronomy11061223 - 16 Jun 2021

Cited by 7 | Viewed by 2502

Abstract

A three-year field study was conducted to evaluate the impact of two different agro-industrial byproducts on soil properties, provisioning services, olive quality and production in a traditional rainfed olive grove to assess suitable management options for recycling organic wastes and reduce the use [...] Read more.

A three-year field study was conducted to evaluate the impact of two different agro-industrial byproducts on soil properties, provisioning services, olive quality and production in a traditional rainfed olive grove to assess suitable management options for recycling organic wastes and reduce the use of inorganic fertilizers. The organic amendments consisted of compost (AC), made from residues from the olive oil industry (“alperujo”), and biosolid compost (BC), constituted of wastewater sludge and green waste from parks and gardens. The compost addition enhanced carbon storage, available phosphorous and potassium content overtime, whereas no effect was detected on soil hydraulics, yield and olive trees growth, partly due to the high variability encountered among plots. Beneficial effects, especially carbon storage, were more evident during the fourth sampling, where carbon content increased by almost 40% for BC, suggesting that compost effects need to be evaluated in the long term. Strong seasonal changes of most of the physico-chemical parameters were detected, and therefore the effect of the compost could have been partly masked. Establishing a non-climatic variation scenario would be advisable to fully detect compost effects. Our results suggest that different agro-industrial byproducts could be potentially viable and valuable source of fertilization, favoring in this way a circular economy of zero waste. Full article

(This article belongs to the Special Issue Recycling Agricultural, Industrial, and Municipal Byproducts While Enhancing Agricultural Production and Protecting the Environment – Volume I)

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13 pages, 280 KiB

Open AccessArticle

Corn Grain and Stover Nutrient Uptake Responses from Sandy Soil Treated with Designer Biochars and Compost

by Jeffrey M. Novak, Donald W. Watts, Gilbert C. Sigua and Thomas F. Ducey

Agronomy 2021, 11(5), 942; https://doi.org/10.3390/agronomy11050942 - 10 May 2021

Cited by 3 | Viewed by 2497

Abstract

Biochars are used for soil fertility improvement because they may contain certain elements that plants use as nutrients. However, few studies have demonstrated enhanced crop nutrient uptake. Our study examined nutrient uptake responses of corn (Zea Mays L.) grain and stover over [...] Read more.

Biochars are used for soil fertility improvement because they may contain certain elements that plants use as nutrients. However, few studies have demonstrated enhanced crop nutrient uptake. Our study examined nutrient uptake responses of corn (Zea Mays L.) grain and stover over 4 years (Y) after a Goldsboro sandy loam (fine-loamy, siliceous, sub-active, thermic Aquic Paleudults) received different designer biochars and a compost. The designer biochars were produced from lodgepole pine (Pinus contorta) chip (PC), poultry litter (PL), blends with switchgrass (SG; Panicum virgatum), and a SG compost alone. Topsoil treated with 100% PL biochar and blended PC:PL biochar had significantly greater Mehlich 1 (M1) extractable P, K and Na contents compared to the control or other treatments. No significant differences were detected in annual grain nutrient concentrations. In the first corn stover harvest (Y₁), significantly greater concentrations of P and K were taken up after treatment with 100% PL biochar, with PC:PL blend and with SG when compared to control. By the fourth corn stover harvest (Y₄), nutrient uptake between treatments was not significantly different. Biochar impact on corn stover P, K and Na concentrations was time dependent, suggesting that repeated biochar applications may be needed. Full article

(This article belongs to the Special Issue Recycling Agricultural, Industrial, and Municipal Byproducts While Enhancing Agricultural Production and Protecting the Environment – Volume I)

18 pages, 1379 KiB

Open AccessEditor’s ChoiceArticle

Physiochemical Characterization of Biochars from Six Feedstocks and Their Effects on the Sorption of Atrazine in an Organic Soil

by Shagufta Gaffar, Sanku Dattamudi, Amin Rabiei Baboukani, Saoli Chanda, Jeffrey M. Novak, Donald W. Watts, Chunlei Wang and Krishnaswamy Jayachandran

Agronomy 2021, 11(4), 716; https://doi.org/10.3390/agronomy11040716 - 9 Apr 2021

Cited by 26 | Viewed by 4020

Abstract

Application of biochars in agricultural soils has the potential to reduce groundwater contamination of atrazine, a widely used herbicide in the US, therefore sustaining environmental quality and reducing human health issues. This study was conducted to characterize biochars produced from six feedstocks and [...] Read more.

Application of biochars in agricultural soils has the potential to reduce groundwater contamination of atrazine, a widely used herbicide in the US, therefore sustaining environmental quality and reducing human health issues. This study was conducted to characterize biochars produced from six feedstocks and investigate their ability to remove and retain atrazine in an organic-rich soil. Australian pine (AP), Brazilian pepper (BP), coconut husk (CH), cypress (Cy), loblolly pine (L), and pecan shell (P) feedstocks were pyrolyzed at 350 °C and 500 °C. Adsorption and desorption behaviors of atrazine were explained using Freundlich isotherms. Higher pyrolysis temperature increased specific surface area (5 times), total pore volume (2.5 times), and aromaticity (1.4 times) of the biochars. CH feedstock produced the most effective biochars (CH350 and CH500), which adsorb 8–12% more atrazine than unamended soils. CH350 biochar performed the best (K_{d ads} = 13.80, K_OC = 153.63, K_{d des} = 16.98) and had significantly higher (p < 0.05) adsorption than unamended soil, possibly resulting from its highest cation exchange capacity (16.32 cmol kg⁻¹). The K_{d des} values for atrazine desorption were greater than the K_{d ads} for adsorption, indicating retention of a considerable amount of atrazine by the biochar-amended soils following desorption. Full article

(This article belongs to the Special Issue Recycling Agricultural, Industrial, and Municipal Byproducts While Enhancing Agricultural Production and Protecting the Environment – Volume I)

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17 pages, 6128 KiB

Open AccessArticle

Adsorptive and Surface Characterization of Mediterranean Agrifood Processing Wastes: Prospection for Pesticide Removal

by José A. Fernández-López, Marta Doval Miñarro, José M. Angosto, Javier Fernández-Lledó and José M. Obón

Agronomy 2021, 11(3), 561; https://doi.org/10.3390/agronomy11030561 - 16 Mar 2021

Cited by 11 | Viewed by 2605

Abstract

The sustainable management of biomass is a key global challenge that demands compliance with fundamental requirements of social and environmental responsibility and economic effectiveness. Strategies for the valorization of waste biomass from agrifood industries must be in line with sustainable technological management and [...] Read more.

The sustainable management of biomass is a key global challenge that demands compliance with fundamental requirements of social and environmental responsibility and economic effectiveness. Strategies for the valorization of waste biomass from agrifood industries must be in line with sustainable technological management and eco-industrial approaches. The efficient bioremoval of the pesticides imazalil and thiabendazole from aqueous effluents using waste biomass from typically Mediterranean agrifood industries (citrus waste, artichoke agrowaste and olive mill residue) revealed that these residues may be transformed into cost-effective biosorbents. Agrifood wastes present irregular surfaces, many different sized pores and active functional groups on their surface, and they are abundant in nature. The surface and adsorptive properties of olive mill residue, artichoke agrowaste and citrus waste were characterized with respect to elemental composition, microstructure, crystallinity, pore size, presence of active functional groups, thermal stability, and point of zero charge. Olive mill residue showed the highest values of surface area (Brunauer–Emmett–Teller method), porosity, crystallinity index, and pH of zero point of charge. Olive mill residue showed the highest efficiency with sorption capacities of 9 mg·g⁻¹ for imazalil and 8.6 mg·g⁻¹ for thiabendazole. Full article

(This article belongs to the Special Issue Recycling Agricultural, Industrial, and Municipal Byproducts While Enhancing Agricultural Production and Protecting the Environment – Volume I)

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13 pages, 2169 KiB

Open AccessArticle

Nitrogen Isotope Fractionation during Composting of Sewage and Agri-Food Sludge with Pruning Waste

by José Antonio Sáez, Pilar Flores, María Ángeles Bustamante, Juan C. Sanchez-Hernandez, Raúl Moral and María Dolores Pérez-Murcia

Agronomy 2020, 10(12), 1954; https://doi.org/10.3390/agronomy10121954 - 12 Dec 2020

Cited by 5 | Viewed by 2435

Abstract

This work studies the changes in δ¹⁵N signature during the composting of sewage sludge (MS) and agri-food sludge (AS) with different bulking agents and the potential relationships between the changes in this parameter with both the source of the organic matter [...] Read more.

This work studies the changes in δ¹⁵N signature during the composting of sewage sludge (MS) and agri-food sludge (AS) with different bulking agents and the potential relationships between the changes in this parameter with both the source of the organic matter used as a raw material and the stability of the end-materials obtained. For this, eleven mixtures were prepared in commercial composting conditions using sewage sludge from municipal wastewater in a range of 60–85% (on a fresh weight basis) or agri-food sludge in a range of 65–75%, mixed with seven different pruning wastes as bulking agents. The thermal profile was monitored throughout the composting processes, and the main physico-chemical and chemical parameters were determined. The results obtained confirmed a correct development of the composting processes, observing slight differences in process evolution depending on the type of sludge used. The composts obtained showed adequate contents of nitrogen, phosphorus and potassium (NPK) and reached a good degree of maturity. Significant differences in the specific nitrogen isotopic composition were found in the initial materials. Moreover, the results suggest that the type of sludge had a main contribution in the δ¹⁵N value of the initial composting mixtures. The use of δ¹⁵N is recommended as an indicator of the composting process, especially to evaluate N dynamics, and the quality of the resultant compost. Full article

(This article belongs to the Special Issue Recycling Agricultural, Industrial, and Municipal Byproducts While Enhancing Agricultural Production and Protecting the Environment – Volume I)

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15 pages, 1609 KiB

Open AccessArticle

Chemical Extraction of Phosphorus from Dairy Manure and Utilization of Recovered Manure Solids

by Ariel A. Szogi, Virginia H. Takata and Paul D. Shumaker

Agronomy 2020, 10(11), 1725; https://doi.org/10.3390/agronomy10111725 - 6 Nov 2020

Cited by 8 | Viewed by 4052

Abstract

Repeated land application of dairy manure can increase soil phosphorus above crop requirements because of manure’s low nitrogen (N) to phosphorus (P) ratio (N:P < 4:1). This soil P build-up can lead to off-site P transport and impairment of surface water quality. We [...] Read more.

Repeated land application of dairy manure can increase soil phosphorus above crop requirements because of manure’s low nitrogen (N) to phosphorus (P) ratio (N:P < 4:1). This soil P build-up can lead to off-site P transport and impairment of surface water quality. We evaluated a treatment process to extract P from manures, called Quick Wash, integrated with a double-stage solids separation system to recover coarse and fine manure solids. The Quick Wash process uses a combination of acid, base, and organic polymers to extract and recover P from manures, improving the N:P ratio of recovered manure solids (RMS). Results showed that coarse RMS could have use as bedding materials for dairy cows, and the fine acidified RMS with N:P > 10:1 can be used as a low-P organic soil amendment. A soil incubation test showed that acidified RMS stimulated N mineralization and nitrification having higher nitrate levels than untreated dairy slurry when incorporated into soil. Our results suggest that the inclusion of Quick Wash in a dairy manure management system can improve manure’s value, lowering costs of bedding material and manure hauling, and recover P for use as fertilizer while reducing the environmental impact of land spreading manure P. Full article

(This article belongs to the Special Issue Recycling Agricultural, Industrial, and Municipal Byproducts While Enhancing Agricultural Production and Protecting the Environment – Volume I)

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19 pages, 9607 KiB

Open AccessArticle

Study of the Mechanics and Micro-Structure of Wheat Straw Returned to Soil in Relation to Different Tillage Methods

by Yanpeng Wang, Adnan Abbas, Xiaochan Wang, Sijun Yang, Morice R. O. Odhiambo, Qishuo Ding, Guoxiang Sun and Yinyan Shi

Agronomy 2020, 10(6), 894; https://doi.org/10.3390/agronomy10060894 - 23 Jun 2020

Cited by 7 | Viewed by 3351

Abstract

A field experiment was conducted to study the effects of different tillage methods, and their interaction on the dynamic changes of straw decomposition rate, mechanical properties, and micro-structure of the stalk. A nylon mesh bag technique was used. An obvious change was observed [...] Read more.

A field experiment was conducted to study the effects of different tillage methods, and their interaction on the dynamic changes of straw decomposition rate, mechanical properties, and micro-structure of the stalk. A nylon mesh bag technique was used. An obvious change was observed in the decomposition rate of straw, and its mechanical, and micro-structural properties. The decomposition rate of straw was increased in all tillage treatments. Specifically, it increased consistently in conventional and dry rotary tillage, and sharply in wet rotary tillage. Furthermore, for all tillage, the mechanical properties like shear and bending strengths decreased sharply while compressive strength first decreased linearly and then increased, whereas the micro-structure of wheat straw showed a fluctuating trend, i.e., it changed neither regularly nor consistently over time. Moreover, the micro-structure of the stalk explained the morphological changes to the straw that returned to the field, which may impact the mechanical properties. However, these changes could not explain the degradation trend of straw directly. The findings of the study could be used as a theoretical reference for the design of tillage and harvesting machinery keeping in view soil solidification and compaction dynamics. Full article

(This article belongs to the Special Issue Recycling Agricultural, Industrial, and Municipal Byproducts While Enhancing Agricultural Production and Protecting the Environment – Volume I)

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8 pages, 228 KiB

Open AccessCommunication

Combined Effects of Dewatering, Composting and Pelleting to Valorize and Delocalize Livestock Manure, Improving Agricultural Sustainability

by Domenico Ronga, Paolo Mantovi, Maria Teresa Pacchioli, Andrea Pulvirenti, Francesco Bigi, Giulio Allesina, Simone Pedrazzi, Aldo Tava and Aldo Dal Prà

Agronomy 2020, 10(5), 661; https://doi.org/10.3390/agronomy10050661 - 8 May 2020

Cited by 21 | Viewed by 3853

Abstract

An agronomic strategy to mitigate climate change impact can be the build-up of soil organic carbon. Among agronomic management approaches, the administration of organic fertilizers like livestock manure represents an effective strategy to increase soil organic carbon. However, livestock manure usually contains a [...] Read more.

An agronomic strategy to mitigate climate change impact can be the build-up of soil organic carbon. Among agronomic management approaches, the administration of organic fertilizers like livestock manure represents an effective strategy to increase soil organic carbon. However, livestock manure usually contains a high amount of water, reducing its sustainable delocalization and impacting on greenhouse gas emissions and nutrient leaching. Furthermore, the possible presence of weed seeds and harmful microorganisms could reduce the agronomic value of the manure. To overcome these issues, the combined effects of dewatering, composting and pelleting were investigated on livestock manure to produce sustainable organic fertilizers. Our results showed that composting and pelleting can represent a feasible and sustainable solution to reduce the potential risks related to the presence of weed seeds and harmful bacteria, concentrating nutrients and allowing a sustainable valorization and delocalization of the livestock manure. In addition, the processed manures were assessed as fertilizers in the growing medium (GM), displaying an increase in water retention and nutrient availability and a decrease of GM temperature and weed seed emergences. However, further study is needed to validate, both in open field and greenhouse productions, the effects of the proposed fertilizers in real cropping systems. Full article

(This article belongs to the Special Issue Recycling Agricultural, Industrial, and Municipal Byproducts While Enhancing Agricultural Production and Protecting the Environment – Volume I)

17 pages, 3959 KiB

Open AccessArticle

Effects of Italian Ryegrass (IRG) Supplementation on Animal Performance, Gut Microbial Compositions and Odor Emission from Manure in Growing Pigs

by Sungkwon Park, Sungback Cho and Okhwa Hwang

Agronomy 2020, 10(5), 647; https://doi.org/10.3390/agronomy10050647 - 2 May 2020

Cited by 12 | Viewed by 3383

Abstract

Fermentable carbohydrate (FC) is a promising material to reduce odor emission from pig manure. This study was conducted to investigate the impact of diets containing Italian ryegrass (IRG), as a FC, on animal performance, odorous chemical and bacterial composition of manure. Pigs were [...] Read more.

Fermentable carbohydrate (FC) is a promising material to reduce odor emission from pig manure. This study was conducted to investigate the impact of diets containing Italian ryegrass (IRG), as a FC, on animal performance, odorous chemical and bacterial composition of manure. Pigs were weighed and fed diets containing various levels of IRG powder (0%, 0.5%, 1.0% and 1.5%) for 28 days. At the end of the trial, manure was collected to analyze the chemical composition, odorous compounds and bacterial community structure. As dietary IRG levels increased, concentrations of phenols and indoles were decreased by 12% and 37% compared with control, respectively, without changes in growth performance. IRG treatment increased the relative abundances of genera belong to the family Lachnospiraceae, Ruminococcaceae, Veillonellaceae, Peptostreptococcaceae and Lactobacillaceae, in order Clostridiales of phylum Firmicutes, but decreased the relative abundances of genus Sphaerochaeta in phylum Spirochaetes and genus AB243818_g of family Porphyromonadaceae in phylum Bacteroidetes when compared with control. Results from the current study demonstrate that IRG supplemented diets had a beneficial effect of reducing the odorous compounds in manure, possibly by altering the bacterial community structure towards predominantly carbohydrate utilizing microorganisms in the large intestine. Full article

(This article belongs to the Special Issue Recycling Agricultural, Industrial, and Municipal Byproducts While Enhancing Agricultural Production and Protecting the Environment – Volume I)

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The Occurrence of Legacy P Soils and Potential Mitigation Practices Using Activated Biochar

by Vasile Cerven, Jeff M. Novak, Ariel A. Szögi, Kenneth Pantuck, Don W. Watts and Mark G. Johnson

Agronomy 2021, 11(7), 1289; https://doi.org/10.3390/agronomy11071289 - 25 Jun 2021

Cited by 7 | Viewed by 3043

Abstract

The long-term application of manures in watersheds with dense animal production has increased soil phosphorus (P) concentration, exceeding plant and soil assimilative capacities. The P accumulated in soils that are heavily manured and contain excess extractable soil P concentrations is known as legacy [...] Read more.

The long-term application of manures in watersheds with dense animal production has increased soil phosphorus (P) concentration, exceeding plant and soil assimilative capacities. The P accumulated in soils that are heavily manured and contain excess extractable soil P concentrations is known as legacy P. Runoff and leaching can transport legacy P to ground water and surface water bodies, contributing to water quality impairment and environmental pollution, such as eutrophication. This review article analyzes and discusses current and innovative management practices for soil legacy P. Specifically, we address the use of biochar as an emerging novel technology that reduces P movement and bioavailability in legacy P soils. We illustrate that properties of biochar can be affected by pyrolysis temperature and by various activating chemical compounds and by-products. Our approach consists of engineering biochars, using an activation process on poultry litter feedstock before pyrolysis to enhance the binding or precipitation of legacy P. Finally, this review article describes previous examples of biochar activation and offers new approaches to the production of biochars with enhanced P sorption capabilities. Full article

(This article belongs to the Special Issue Recycling Agricultural, Industrial, and Municipal Byproducts While Enhancing Agricultural Production and Protecting the Environment – Volume I)

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Recycling Agricultural, Industrial, and Municipal Byproducts While Enhancing Agricultural Production and Protecting the Environment – Volume I

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