Livestock Bedding Research Articles

Potential of Wheat Straw for Biogas Production by Anaerobic Digestion in South Africa: A Review

Wheat straw (WS) is a promising substrate for biogas production by anaerobic digestion (AD) due to its high carbohydrate content. An estimated 0.603 million t yr−1 of WS are generated from wheat production systems in South Africa. This is equivalent to an energy potential of 11 PJ. Despite this, WS is still undervalued as a bioenergy resource in South Africa due to its structural complexity and low nitrogen content. WS disposal methods, such as use in livestock bedding, burning and burying into the soil, inter alia, are not sustainable and may contribute to global warming and climate change. The commercialization of the AD of WS needs to be further developed and promoted. Pre-treatment (i.e., physical, chemical, biological and hybrid methods) and anaerobic co-digestion (AcoD) are novel strategies that can support the conversion of WS into biogas and other value-added products. Current and future research should focus on optimizing pre-treatment and AcoD conditions towards industrialization of WS into valuable products. This paper focuses on the potential use of WS for biogas production in South Africa. The aim is to create information that will promote research and development, and encourage policy makers and stakeholders to participate and invest in WS biogas technology. Were WS biogas technology fully adopted, we believe that it would alleviate energy insecurity and environmental degradation, and sustain the livelihoods of citizens in South Africa.

Innovative bedding materials for compost bedded pack barns: enhancing dairy cow welfare and sustainable dairy farming

AbstractCompost bedded pack (CBP) barns are an innovative housing system that improves the comfort and welfare of dairy cows, compared to cubicle style housing or free stalls with artificial surfaces, such as rubber or concrete. This type of bedding system also has the potential to improve lameness scores, overall health, welfare, and productivity of dairy cows. In CBP barns, carbon materials or organic materials are composted in the barn while being used as bedding for livestock. The animals pass manure on these surfaces providing the nitrogen, microorganisms, and moisture necessary for the composting process. Historically, dry sawdust originating from mills, furniture and pallets have been used as a substrate for compost. However, due to these materials becoming increasingly expensive and hard to source, other materials have been trailed as potential substitutes. Furthermore, there is an increasing interest in making dairy production more environmentally friendly by reducing carbon footprint. This review summarises and highlights appropriate alternative materials that, subject to their management, can be successfully used in the CBP barn system. This will act as an aid for farmers and decision makers when choosing materials to be incorporated in CBP barns. Using alternative materials to sawdust, wood chips and wood shavings, which are the current industry standard, will contribute to a more circular economy and sustainable dairy production, while simultaneously contributing to sustainable development goals, and improved animal health and welfare.

Preferences for livestock bedding as a development substrate of the stable fly, Stomoxys calcitrans L. (Diptera: Muscidae), and potential application of entomopathogenic nematodes for controlling stable fly larvae.

The stable fly, Stomoxys calcitrans L. (Diptera: Muscidae), is a significant insect pest with global veterinary implications due to its capacity to both cause nuisance and transmit disease-causing pathogens to livestock. This study aimed to determine the livestock bedding preferred for use as a development substrate by S. calcitrans larvae and field-collected adults. The result showed that S. calcitrans larvae exhibited a preference (26.7%) for 7-day-old cow manure. Gravid females displayed a pronounced preference (55.0%) for fresh cow manure. As there were eight choices, indifference would result in 12.5% for each bedding substrate. Furthermore, the efficacy of four entomopathogenic nematodes (EPNs), namely Heterorhabditis bacteriophora (Poinar), Heterorhabditis indica Poinar, Karunakar & David (Rhabditida: Heterorhabditidae), Steinernema siamkayai Poinar, Karunakar & David and Steinernema carpocapsae (Weiser) (Rhabditida: Steinernematidae), against S. calcitrans larvae and the persistence after application to livestock bedding substrates were evaluated under laboratory conditions. In filter paper bioassays, all four EPNs caused 76.7%-100.0% mortality in the second instar larvae of S. calcitrans when applied at 50 and 100 infective juveniles (IJs)/cm2 within 5 days after exposure. For the third instar larvae of S. calcitrans, only H. indica induced high mortalities of 86.6% when applied at 100 IJs/cm2 within 5 days after exposure, while the other EPNs resulted in mortalities of less than 70%. The data further demonstrated that H. bacteriophora, H. indica and S. siamkayai remained present in the substrates linked to S. calcitrans larvae for as long as 7 days after the application of EPNs. This study demonstrates the potential of EPNs as a biologically based control agent against larvae of S. calcitrans, a serious pest and significant vector for various livestock animals.

Bioenergy feedstock supply from wheat straw: A farm level model incorporating trade‐offs in crop choices, disease risk, and soil fertility

AbstractSecond‐generation biofuel (e.g., ethanol, renewable diesel) can be made from crop residues. However, the availability of residues for biofuel production is uncertain, because farmers have the option to grow different crops and use the residues for alternative purposes, such as livestock bedding and feed, or leave them in the field to improve soil quality. Taking Canadian wheat straw supply as an example, we develop a dynamic programming model to investigate a farmer's wheat straw supply decision in response to different wheat straw and grain prices. Our model considers crop choices between wheat and canola in the context of disease risk, the trade‐off between the immediate payoffs a farmer may receive from bailing and selling wheat straw, and the long‐term adverse effects that removing wheat straw from the soil surface may have on wheat and canola yields. The results from this study provide insights into how farm‐level supply decisions, in response to wheat straw price changes, affect soil quality dynamics and scale up to regional wheat straw supply for biofuel production. This information also has implications for land use change and the sustainability of feedstock supply for biofuels.

Dominance of Diarrheagenic E. coli Virulent Types in Integrated Crop–Livestock Farms and Their Antibiotic Resistance Patterns

Microbial ecology on integrated crop–livestock farms (ICLFs) can impact food safety through pathogen transfer between animals and crops. Recent reports of pathogen-contaminated products sold in local organic retail, roadside, and farmers markets highlight the need for assessment of the ecological patterns of bacterial pathogens. This study investigated the prevalence and antibiotic resistance of the virulent type of diarrheagenic E. coli in ICLFs. Over two years, 2973 samples from ICLFs and markets in Maryland and Washington DC were analyzed. Diarrheagenic E. coli was found in 4.30% (128/2973) of collected samples, with a higher isolation rate in environmental (4.42%, 59/1332) and produce (4.20%, 69/1641) samples. Overall, livestock bedding materials had the highest prevalence (8.51%, 4/47). Post-harvest produce exhibited a lower contamination rate of 1.32% (10/756), whereas pre-harvest produce had a higher incidence with 6.67% contamination (59/885), indicating the presence of E. coli. Alarmingly, 92.30% (72/78) of pathogenic E. coli isolates were resistant to common antibiotics. The findings highlight potential risks associated with integrated farming practices and emphasize the importance of safe harvesting and post-harvesting measures, particularly in the context of the growing popularity of local integrated farming. Implementing precautions at on-farm and market levels is crucial to mitigate the risk of antibiotic-resistant E. coli-related enteric illnesses, safeguarding both consumers and the integrity of integrated farming systems.

ИСПОЛЬЗОВАНИЕ ТОРФОПРОДУКЦИИ В СЕЛЬСКОМ ХОЗЯЙСТВЕ

Peat products play an important role in agriculture. An analysis of the use of peat products in agriculture was carried out. It was noted that in livestock farming, peat is used as bedding for livestock to produce peat manure, peatponics, the production of protein and feed additives, silos, and the production of drugs from peat in veterinary medicine. Peat is used to improve soil fertility, create substrates, for growing seedlings, for mulching the soil and protecting plants from frost and weeds in crop production. The use of peat briquettes as fuel for heating greenhouses and livestock buildings is possible. After burning them, peat ash remains - a good fertilizer. The organic and chemical composition of peat is shown. For the effective processing of peat and the use of peat products, it is proposed to create an agricultural consumer cooperative (ACC). A model of the interaction of structure-forming elements of ACC for peat processing is presented. The creation of an industrial complex for the processing and integrated use of peat products is promising, since it realizes the simplicity of technical solutions, the possibility of scaling processes, short lead times and the environmental friendliness of the resulting products. The integrated use of peat products in agriculture allows not only to improve soil fertility and increase crop yields, but also to ensure the effective use of peat as fuel, feed additives, animal bedding, oil product sorbent, etc.

Evidence of compost contamination with per- and polyfluoroalkyl substances (PFAS) from "compostable" food serviceware.

Per- and polyfluoroalkyl substances (PFAS) have been used to waterproof and greaseproof food serviceware for decades. Health concerns about these compounds have drawn attention to the potential for contamination of the food system. Finished compost (n = 3) made from manure and food serviceware labeled "compostable" generated at a large fair was found to contain 12 or 13 of the 28 PFAS compounds sampled for, in concentrations ranging from 1.1 to 183 μg/kg (Σ28PFAS range = 209-455 μg/kg). Of note, perfluorooctanoic acid, a known carcinogen, was found at concentrations between 47.2 and 55.5 μg/kg. In contrast, fresh manure contained only perfluoroctanesulfonic acid at 3.7 μg/kg, and separated food waste from the fair composted with grass clippings and livestock bedding had no detectable PFAS in 2022, and Σ28PFAS = 9.6 μg/kg in 2019. Including compostable serviceware in compost likely contaminates the finished compost and threatens surrounding groundwater and surface waters, in addition to increasing potential crop uptake.

Potentials, subsidies and tradeoffs of cellulosic ethanol in the European Union

The EU's revised Renewable Energy Directive (RED2) sets high mandates for advanced biofuels like cellulosic bioethanol from agricultural residues. However, many residues are used for ecological and economic purposes such as soil organic carbon regulation and livestock bedding and fodder. We use the global CGE model DART-BIO with a detailed representation of the bioeconomy to simulate the RED2 cellulosic bioethanol mandates and run sensitivity analyses regarding processing technology, straw and oil prices. We implement a latent cellulosic ethanol technology and develop new sectors for agricultural residues. We find that the RED2 cellulosic ethanol mandates will require enormous amounts of residues that could exceed the sustainable available potential in the EU. Agricultural residue utilization changes substantially and the cellulosic ethanol industry becomes the main residue consumer. Results show that output and price impacts of advanced biofuel targets are small, but there is reallocation of land towards cereals that enter the agricultural residue sector away from other crops in the EU. Moreover, the size of necessary cellulosic ethanol subsidies and the abatement costs per tonCO2eq are very sensitive to actual straw and oil prices.

Equipment Performance, Costs and Constraints of Packaging and Transporting Rice Straw for Alternative Uses to Burning in the “Parc Natural l’Albufera de València” (Spain)

Rice straw is a residue that causes significant environmental problems, as burning it causes CO2 and ash emissions, while buried waste can cause issues associated with eutrophication. The extraction of straw from fields for alternative uses may contribute to solving these problems, but research into its economic viability is necessary. The straw can be used for crop mulching, biofuel, bedding for livestock, and so on. In this study, we analyse the work carried out by straw harvesting machines (rakes, balers, bundlers, and loaders) and calculate the costs of packing, road-siding, and transportation of the straw from the rice fields to stockage points in the producer area, as well as to locations outside of the rice production area, in order to assess the viability. The costs of all elemental operations were calculated. The costs of all the operations included between raking and unloading in the producer area stocking point ranged between 28.1 and 51 EUR t−1. These costs were compared with the price of rain-fed cereal straw (wheat and barley), which is the most abundant, noting that the years in which rain-fed cereal straw reached high prices, rice straw could serve as a competitive product; however, in years when the former is cheap, it would be necessary to subsidise the harvesting of rice straw.

Management of Soil Fertility and Agricultural Intensification in NW Iberia, 1750–1900

Abstract This article describes agricultural practices of fertilization in the NW of the Iberian Peninsula between 1750 and 1900, where a leguminous plant called gorse (Ulex Europaeus) was used as bedding for livestock in order to produce manure. During the period examined, this whole region experienced a process of agricultural intensification which resulted in a net loss of nutrients in the soil. Peasants dealt with the increasing nutrient requirements by adapting land and livestock management in order to produce more manure during the second half of the 20th century. However, this was done at the expense of nutrient reserves in extensively managed areas, all of which resulted in an unsustainable agricultural pattern. Our data also suggest that the context of nutrient scarcity could be related to changes in the migration pattern, which started to be more intense after 1850 and preferred distant destinations (America), thus switching from seasonal to permanent stays.

Associations between faecal pathogen detection, E.coli concentrations and youth exhibitor biosecurity practices at California county fairs.

Interactions with livestock in public settings such as county and state fairs can expose people and other livestock to faecal material capable of spreading zoonotic enteric pathogens. The goal of this study was to understand these risks by screening livestock faeces (n=245) and livestock bedding (n=155) for common zoonotic pathogens (Giardia, Cryptosporidium, Salmonella and Campylobacter spp.) and by measuring faecal indicator, Escherichia coli, concentrations in drinking water (n=153), feed containers (n=124) and bedding material (n=157) in four livestock species (cattle, sheep, goats and swine) from county fairs in California, USA. Results indicated that sheep were most likely to have pathogens detected in faeces and that Giardia was the most frequently detected pathogen in both faeces (11%) and bedding (21%) across all livestock species. Additionally, increasing the number of animals in a holding pen at fairs, increasing the stocking density of animals in transport trailers to fairs, and having access to water in transport trailers significantly increased the odds of detecting pathogens in livestock faeces of any animal species. Observing solid material in water, stale feed and soiled bedding was associated with detecting higher E.coli concentrations. These findings provide evidence of faecal pathogens present at county fairs and suggest that site observations can aid in assessing levels of faecal exposure. The findings also indicate that the use of biosecurity measures such as (a) routine changing of livestock drinking water, feed and bedding, (b) not overstocking animals in holding pens and trailers and (c) keeping species in separate holding areas may reduce the risk of humans and livestock being exposed to faecal pathogens.

Factors affecting evaporation of water from cattle bedding materials

In livestock farming, maintaining dry bedding is considered to be important for maximising animal performance and welfare. A better understanding of the mechanisms that regulate drying has the potential to improve bedding management and reduce production costs. A custom laboratory-scale method was developed to explore the effects of environmental conditions and bedding characteristics on drying rate (DR). Samples (n = 256) of different types of bedding materials were exposed to controlled environmental conditions by using a climate chamber equipped with a custom cabinet capable of simulating different levels of air velocity and bedding temperature. The effects of the type of material, bedding moisture content, bedding temperature, air temperature, air relative humidity (RH) and air velocity were evaluated in a full factorial experimental design. Under the experimental conditions tested, DR ranged from 0.28 to 6.04 kg m −2 d −1 , with an average of 2.03 kg m −2 d −1 . All variables significantly affected DR, but large variation in the magnitude of effects was found. Bedding moisture content, air velocity and air RH had considerably larger effects than the other variables, together accounting for more than 70% of the variance in DR. The DR from bedding samples increased with bedding moisture content and air velocity but decreased with increasing air RH. The results of the current study may have important implications in the design and management of bedded pack barns. To increase the DR and keep bedding dry, producers should focus primarily on providing adequate barn ventilation (both in terms of air velocity and air exchange), whereas maintaining a high pack temperature may yield poorer-than-expected results. • Water evaporation from livestock bedding materials has been measured experimentally. • Drying rate depends on environmental conditions and bedding characteristics. • Bedding moisture content, air velocity and air RH are the most important factors. • Producers with bedded pack barns should focus on providing adequate ventilation.

Conservation of a strongly declining butterfly species depends on traditionally managed grasslands

Introduction:Due to land-use intensification at productive soils and abandonment of marginal farmland, biodiversity has dramatically declined throughout Europe. The dryad (Minois dryas) is a grassland butterfly that has strongly suffered from land-use change across Central Europe.Aims/Methods:Here, we analysed the habitat preferences of adult M. dryas and the oviposition-site preferences in common pastures located in mire ecosystems of the German pre-Alps.Results:Our study revealed that plot occupancy was equal at common pastures and control plots. However, the abundance of M. dryas was higher at common pastures, although the composition of vegetation types did not differ between the two plot types.Discussion:Open fens and transition mires traditionally managed as common pastures or litter meadows (= meadows mown in autumn to obtain bedding for livestock) were the main habitats of M. dryas in our study area. They offered (i) sufficient host plants (Carex spp.), (ii) had a high availability of nectar resources and (iii) a vegetation that was neither too sparse nor too short. In contrast, both abandonment and intensive land use had negative impacts on the occurrence of the endangered butterfly species.Implications for Insect ConservationBased on our study and other recent research from the common pastures, we recommend to maintain the current grazing regime to foster biodiversity in general and M. dryas in particular. Additionally, where possible, abandoned fens and transition mires adjacent to common pastures should be integrated into the low-intensity pasture systems. The preservation of traditionally managed litter meadows is the second important possibility to conserve M. dryas populations.

Batch mesophilic anaerobic co-digestion of spent goat batch mesophilic anaerobic co-digestion of spent goat straw bedding and goat cheese whey: Comparison with the mono-digestion of the two sole substrates

Spent livestock bedding is a valuable resource for the production of green energy (methane) in rural areas. Comparison and evaluation of batch anaerobic digestion and co-digestion of different mixtures of goat straw bedding (SGSB) and goat cheese whey were carried out. Biochemical methane potential (BMP) tests of the 100% SGSB, 95% SGSB-5% whey, 90% SGSB-10% whey, 85% SGSB-15% whey and 100% whey were found to be 423 ± 7, 354 ± 9, 371 ± 2, 293 ± 1, 274 ± 2 mL CH4 g−1 VS. Two different kinetic models were evaluated. The logistic model revealed a decrease in the maximum methane production rate (Rm) from 34.7 ± 1.5 to 14.1 ± 0.9 mL CH4 g−1 VS·d−1 when the percentage of whey in the mixture increased from 0 to 15% as a consequence of the increased ammonia released during the co-digestion of increased concentrations of whey. The lowest value for the maximum methane production predicted by the model (P) was found for 100% whey (274 ± 10 mL CH4 g−1 VS). A two-substrate model was applied to describe the evident existence of rapid and slowly degradable material. Regarding the hydrolysis kinetic constants predicted by this model, considerable increases in the rapid biodegradation stage (krapid) were observed when comparing to the values found for the slow (kslow) biodegradation stage in all the cases tested. The increases between both constants rose from 5 to 42% when the percentage of whey increased.

Environmental and Health Impact of Open Burning Rice Straw

Introduction: Egypt is an agricultural country and the largest rice producer in the Middle East region. It is an important strategic crop that is planted in Nile Delta area. The term rice straw describes the dry stalks of the rice crop that remains after the removal of the grain during harvesting process. Rice straw biochemical composition is the typical structure of agricultural- based lignocellulosic residue. Farmers all over the world had the habit of open burning of rice straw as a disposal method of the voluminous residues of harvested rice. This practice causes significant amount of air pollutants like gases as NOx, CO, CO2, fine dust (PM2.5, and PM10), that affects the air quality, leads to climatic changes and deteriorates public health. The Egyptian Ministry of Environmental Affairs had controlled this practice that has both environmental and health impacts, through installing intelligent monitors all over Egypt that give alarm in case of exceeding the limits stated by the national environmental law. Efforts had been directed towards onsite collection of rice straw and convincing farmers to recycle the straw into a wide range of products and to provide them with machines for the processing of the rice straw for free added to exploring opportunities of agro-industrial uses as household fuel, livestock bedding, papers, fertilizers, furniture and construction. Consequently, increase the commercial demand for rice straw that derived up prices resulting in the establishment of more rural activities and services. This act improvedthe air quality and reduced the negative impact on the environment and public health.

Impacts of corn stover removal on carbon dioxide and nitrous oxide emissions

AbstractHarvesting corn (Zea mays L.) stover for production of biofuels, industrial sugars, bioproducts, and livestock bedding is increasing rapidly, but little is known of the impacts of stover removal on soil‐borne greenhouse gas (GHG) emissions. This study evaluated the impacts of removing surface corn stover (0, 25, 50, 75, 100 wt. % removal) on carbon dioxide (CO2) and nitrous oxide (N2O) emissions from a sandy loam soil cropped to monoculture corn using conventional moldboard plow tillage (CT) and no‐tillage (NT). Stover removal systematically decreased CO2 emissions from CT, whereas stover removal had little effect on CO2 emissions from NT. In particular, the CT 0% stover removal treatment produced 47% greater CO2 emissions (5.75 Mg CO2–C ha−1) than the CT 100% removal (3.91 Mg CO2–C ha−1) treatment. Stover removal increased N2O emissions from both tillage treatments, producing up to a 75% increase under CT (2.79 kg N ha−1 at 0% removal; 4.87 kg N ha−1 at 100% removal) and up to a 95% increase under NT (1.75 kg N ha−1 at 0% removal; 3.41 kg N ha−1 at 100% removal). Cumulative nitrate exposure increased in comparable patterns to N2O emissions when stover residues were removed. There was a trade‐off in GHG emissions resulting from stover removal under CT, whereby increasing stover removal reduced CO2 emissions but increased N2O emissions. In contrast, stover removal did not affect CO2 emissions under NT but it increased N2O emissions especially at the 100% removal rates.

ENDOZOOCHORY - THE SOURCE OF WEDDING OF AGRICULTURAL CROPS

"One of the most important sources of weed infestation in agricultural crops is related to manure applied as biological fertilizer, when livestock growers don`t process it and don`t store it in order to be weeds - free. In manure there are lot of weed seeds from animal fodder, livestock bedding and also from animal excrements. On the pasture, when grazing fresh food, animals eat also the inflorescences with weed seeds. Ones of these seeds could pass through the digestive tract of animals while keeping their ability to germinate. The aim of this study was to record the weed species that can cross over the digestive tract without losing their germination, to note which weed species are more adapted to do this, which animal species are able to perform the endozoochory process and under what environmental conditions. Trials were conducted under laboratory conditions. The content of excrements taken from four animals species (cattle, goats, sheep, horses), from four distinct South – East areas in period 2019-2020, were mixed with sterilized soil and put to germinate under controlled conditions of temperature and humidity. Following the assessments, weed seeds were found to be able to cross over the digestive tract of animals maintaining their germination. The highest frequency was in cattle and the lowest was in horses. There was at Pasărea where the largest number of weeds was found and animals grazed on untillaged land (hences, fallow lands). The dominant weed species were Setaria sp., Chenopodium sp., Amaranthus retroflexus and Polygonum aviculare."

Simulating switchgrass aboveground biomass and production costs in eastern Canada with the Integrated Farm System Model

Switchgrass (Panicum virgatum L.) is a herbaceous perennial grass that can be used as bedding for livestock, planted in buffer strips, and used as biofuel, but it is still not widely grown in eastern Canada. The objectives of this study were to verify the performance of the Integrated Farm System Model (IFSM) in simulating switchgrass growth and to estimate its yield potential and production costs in eastern Canada. The performance of IFSM was assessed with dry matter (DM) yield of switchgrass (‘Cave-in-Rock’) measured over three growing seasons (2015–2017) in southern Quebec, Canada. The model performed reasonably well, with normalized root mean square errors of 19.5% for calibration and 27.9% for validation. Simulation results of potential yield and economic management over the long term (1986–2015) for five switchgrass production sites in eastern Canada indicated that average DM yields in Quebec City and Fredericton (9.6 and 9.7 t ha−1, respectively) were significantly lower than average DM yields in Saint-Hubert, Ottawa, and London (10.8, 10.4, and 11.0 t ha−1, respectively). Average annual production costs per tonne of DM for the spring harvest were higher at low-yield sites (CAD$66.67 and $64.50 for Fredericton and Quebec City, respectively) than at high-yield sites ($60.10, $62.82, and $60.08 for Saint-Hubert, Ottawa, and London, respectively). The IFSM-estimated production costs were within the range of the calculated values reported in other agro-economic analyses conducted in Ontario and Quebec.

Consequential life cycle assessment of miscanthus livestock bedding, diverting straw to bioelectricity generation

AbstractStraw is an important livestock bedding material facing increasing demand for alternative uses in Europe and is often transported long distances from arable to livestock regions. Alternative bedding materials cultivated directly on livestock farms could potentially avoid this transport and competition for use. For the first time, we applied consequential life cycle assessment (LCA) to account for the direct and indirect implications of miscanthus bedding production on livestock farms, considering displacement of fodder or livestock, and substitution of fossil fuels with straw in electricity generation. We modelled the effect of substituting straw with ‘home‐grown’ miscanthus bedding across seven beef and sheep farms. The consequences of displacing grass forage (or animal) production with home‐grown miscanthus bedding cultivation were evaluated via three farmer decision scenarios: buy extra concentrate feed (D1), utilize remaining pasture areas more efficiently (D2) and buy grass silage (D3). Electricity generated from displaced straw (bedding) substituted either natural gas or coal electricity. Sensitivity analyses were undertaken using 34 scenario permutations to represent combinations of feed and electricity substitution, miscanthus fertilization rates and yields, and the quality of displaced pasture. Consequential LCA indicates that miscanthus bedding production could be environmentally beneficial, under scenarios involving D2 and D3. However, greenhouse gas emissions and wider environmental burdens may be increased under D1 scenarios, owing to the environmental cost of additional concentrate feed production, and possible indirect land use change, outweighing the benefits from: (a) fossil electricity substitution with straw bioelectricity; (b) reduced animal emissions via improved digestibility of concentrate feed; (c) avoided straw transport. The ratio of the yield of miscanthus to replaced grass was found to be a critical determinant of D1 environmental outcomes. We conclude that if grass forage production can be better managed, the use of miscanthus as a bedding material on livestock farms provides environmental benefits via diversion of straw to bioenergy use.

Techno-economic assessment of corn stover for hybrid bioenergy production: A sustainable approach

Corn stover (CS) contains high moisture in the fall and farmers keep it unharvested until next spring for its natural drying. CS contains 70% more carbon than other grain crop residues. Farmers traditionally use a portion of CS for livestock bedding and cattle feed but the rest is kept unharvested. Potential soil erosion, carbon sequestration, and nutrient removal concerns might be considered before CS harvesting. Hydrothermal carbonization (HTC) of wet biomass can produce energy dense solid bio-carbon. Hydrothermal process water (HTPW) can produce energy and recover nutrient in anaerobic digestion (AD). This study reported the results of various experiments performed on non-rooted fall harvested CS of an Ontario farm. Ontario CS was finally assessed for techno-economic and environmental aspects. This research showed 78% energy and a portion on nutrients as liquid bio-fertilizer of fall harvested CS are recoverable. Corn roots with 6–10 cm stalks, cobs and husks can be kept in the soil to recover soil organic matter (SOM) and protection of soil erosion. The process indicates the sustainable CS harvesting in the fall with possibility to reduce 75% of existing harvesting cost and reduction of greenhouse gas (GHG) emission.