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Manure-derived organic amendments are a cost-effective tool that provide many potential benefits to plant and soil health including fertility, water retention, and disease suppression. A greenhouse experiment was conducted to evaluate how dairy manure compost (DMC), dairy manure compost-derived vermicompost (VC), and dehydrated poultry manure pellets (PP) impact the tripartite relationship among plant growth, soil physiochemical properties, and microbial community composition. Of tomato plants with manure-derived fertilizers amendments, only VC led to vigorous growth through the duration of the experiment, whereas DMC had mixed impacts on plant growth and PP was detrimental. Organic amendments increased soil porosity and soil water holding capacity, but delayed plant maturation and decreased plant biomass. Composition of bacterial communities were affected more by organic amendment than fungal communities in all microhabitats. Composition of communities outside roots (bulk soil, rhizosphere, rhizoplane) contrasted those within roots (endosphere). Distinct microbial communities were detected for each treatment, with an abundance of Massilia, Chryseolinea, Scedosporium, and Acinetobacter distinguishing the control, vermicompost, dairy manure compost, and dehydrated poultry manure pellet treatments, respectively. This study suggests that plant growth is affected by the application of organic amendments not only because of the soil microbial communities introduced, but also due to a synergistic effect on the physical soil environment. Furthermore, there is a strong interaction between root growth and the spatial heterogeneity of soil and root-associated microbial communities.
Taylor Readyhough; Deborah Neher; Tucker Andrews. Organic Amendments Alter Soil Hydrology and Belowground Microbiome of Tomato (Solanum lycopersicum). Microorganisms 2021, 9, 1561 .
AMA StyleTaylor Readyhough, Deborah Neher, Tucker Andrews. Organic Amendments Alter Soil Hydrology and Belowground Microbiome of Tomato (Solanum lycopersicum). Microorganisms. 2021; 9 (8):1561.
Chicago/Turabian StyleTaylor Readyhough; Deborah Neher; Tucker Andrews. 2021. "Organic Amendments Alter Soil Hydrology and Belowground Microbiome of Tomato (Solanum lycopersicum)." Microorganisms 9, no. 8: 1561.
Tucker Andrews; Caitlin E. Jeffrey; Rachel E. Gilker; Deborah A. Neher; John W. Barlow. Design and implementation of a survey quantifying winter housing and bedding types used on Vermont organic dairy farms. Journal of Dairy Science 2021, 104, 8326 -8337.
AMA StyleTucker Andrews, Caitlin E. Jeffrey, Rachel E. Gilker, Deborah A. Neher, John W. Barlow. Design and implementation of a survey quantifying winter housing and bedding types used on Vermont organic dairy farms. Journal of Dairy Science. 2021; 104 (7):8326-8337.
Chicago/Turabian StyleTucker Andrews; Caitlin E. Jeffrey; Rachel E. Gilker; Deborah A. Neher; John W. Barlow. 2021. "Design and implementation of a survey quantifying winter housing and bedding types used on Vermont organic dairy farms." Journal of Dairy Science 104, no. 7: 8326-8337.
The authors would like to make the following correction for the published paper
Katherine Porterfield; Robert Joblin; Deborah Neher; Michael Curtis; Steve Dvorak; Donna Rizzo; Joshua Faulkner; Eric Roy. Erratum: Porterfield, K.K. et al. Upcycling Phosphorus Recovered from Anaerobically Digested Dairy Manure to Support Production of Vegetables and Flowers. Sustainability 2020, 12, 1139. Sustainability 2020, 12, 10441 .
AMA StyleKatherine Porterfield, Robert Joblin, Deborah Neher, Michael Curtis, Steve Dvorak, Donna Rizzo, Joshua Faulkner, Eric Roy. Erratum: Porterfield, K.K. et al. Upcycling Phosphorus Recovered from Anaerobically Digested Dairy Manure to Support Production of Vegetables and Flowers. Sustainability 2020, 12, 1139. Sustainability. 2020; 12 (24):10441.
Chicago/Turabian StyleKatherine Porterfield; Robert Joblin; Deborah Neher; Michael Curtis; Steve Dvorak; Donna Rizzo; Joshua Faulkner; Eric Roy. 2020. "Erratum: Porterfield, K.K. et al. Upcycling Phosphorus Recovered from Anaerobically Digested Dairy Manure to Support Production of Vegetables and Flowers. Sustainability 2020, 12, 1139." Sustainability 12, no. 24: 10441.
The aim of this study was to determine whether and how poultry litter compost and dairy manure compost alter the microbial communities within field soils planted with spinach. In three successive years, separate experimental plots on two fields received randomly assigned compost treatments varying in animal origin: dairy manure (DMC), poultry litter (PLC), or neither (NoC). The composition and function of bacterial and fungal communities were characterized by the amplicon sequencing of marker genes and by the ecoenzyme activity, respectively. The temporal autocorrelation within and among years was adjusted by principal response curves (PRC) to analyze the effect of compost on community composition among treatments. Bacteria in the phylum Bacteriodetes, classes Flavobacteriia and Spingobacteriales (Fluviicola, Flavobacteriia, and Pedobacter), were two to four times more abundant in soils amended with PLC than DMC or NoC consistently among fields and years. Fungi in the phylum Ascomycota were relatively abundant, but their composition was field-specific and without treatment differences. The ecoenzyme data verify that the effects of PLC and DMC on soil communities are based on their microbial composition and not a response to the C source or nutrient content of the compost.
Deborah A. Neher; Marie A. Limoges; Thomas R. Weicht; Manan Sharma; Patricia D. Millner; Catherine Donnelly. Bacterial Community Dynamics Distinguish Poultry Compost from Dairy Compost and Non-Amended Soils Planted with Spinach. Microorganisms 2020, 8, 1601 .
AMA StyleDeborah A. Neher, Marie A. Limoges, Thomas R. Weicht, Manan Sharma, Patricia D. Millner, Catherine Donnelly. Bacterial Community Dynamics Distinguish Poultry Compost from Dairy Compost and Non-Amended Soils Planted with Spinach. Microorganisms. 2020; 8 (10):1601.
Chicago/Turabian StyleDeborah A. Neher; Marie A. Limoges; Thomas R. Weicht; Manan Sharma; Patricia D. Millner; Catherine Donnelly. 2020. "Bacterial Community Dynamics Distinguish Poultry Compost from Dairy Compost and Non-Amended Soils Planted with Spinach." Microorganisms 8, no. 10: 1601.
Dissolved air flotation (DAF) separates phosphorus (P)-rich fine solids from anaerobically digested dairy manure, creating opportunities to export surplus P to the marketplace as a bagged plant food product. Seedlings of tomato and marigold were amended at various volume per volume (v/v) ratios with plant foods consisting of fine solids upcycled (i.e., transformed into a higher quality product) by drying and blending with other organic residuals. A plate competition assay was conducted to assess the fine solids’ potential to suppress the plant pathogen Rhizoctonia solani. Plant foods were comprised of 2.0–2.1% N, 0.8–0.9% P and 0.6–0.8% K. Extractions indicated that plant foods contained a mixture of plant-available and slow-release P. At 6% v/v plant food, dry biomass of marigold and tomato were six-times greater than the unamended control and not significantly different from a market alternative treatment. Fine solids exhibited negligible potential to suppress R. solani. This study indicates that DAF-separated fine solids could be used to support horticulture, providing information for design of a circular economy approach to dairy manure nutrient management. Life cycle assessment and business model development for this nutrient recovery strategy are necessary next steps to further guide sustainability efforts.
Katherine K. Porterfield; Robert Joblin; Deborah A. Neher; Michael Curtis; Steve Dvorak; Donna M. Rizzo; Joshua W. Faulkner; Eric D. Roy. Upcycling Phosphorus Recovered from Anaerobically Digested Dairy Manure to Support Production of Vegetables and Flowers. Sustainability 2020, 12, 1139 .
AMA StyleKatherine K. Porterfield, Robert Joblin, Deborah A. Neher, Michael Curtis, Steve Dvorak, Donna M. Rizzo, Joshua W. Faulkner, Eric D. Roy. Upcycling Phosphorus Recovered from Anaerobically Digested Dairy Manure to Support Production of Vegetables and Flowers. Sustainability. 2020; 12 (3):1139.
Chicago/Turabian StyleKatherine K. Porterfield; Robert Joblin; Deborah A. Neher; Michael Curtis; Steve Dvorak; Donna M. Rizzo; Joshua W. Faulkner; Eric D. Roy. 2020. "Upcycling Phosphorus Recovered from Anaerobically Digested Dairy Manure to Support Production of Vegetables and Flowers." Sustainability 12, no. 3: 1139.
Anaerobic co-digestion of dairy manure and food wastes is increasing in the New England region of the United States because of policy measures intended to divert organic materials from landfills, reduce greenhouse gas emissions, and increase renewable biogas energy production. The sustainability of this approach depends on the management and valorization of remaining solid and liquid residues (i.e., digestates) after anaerobic digestion. Few studies have characterized digestates derived from combined dairy manure and food waste feedstocks. In this study, we analyzed screw-press separated liquid and solid digestates from 6 of 26 (23%) operational full-scale facilities in New England. We quantified multiple pools of nitrogen and phosphorus in these materials, with results suggesting that, in most cases, these nutrients largely exist in forms that can be recycled via slow-release fertilization, with smaller fractions in forms more easily lost to the environment. Furthermore, we found that solid digestates can inhibit mycelial growth of a common soilborne fungal pathogen, Rhizoctonia solani, suggesting potential to manage resident soil pathogens. Capitalizing on both nutrient recycling and pathogen suppression co-benefits will likely be useful in digestate valorization efforts.
Brendan J. O’Brien; Deborah A. Neher; Eric D. Roy. Nutrient and Pathogen Suppression Properties of Anaerobic Digestates from Dairy Manure and Food Waste Feedstocks. Waste and Biomass Valorization 2019, 11, 6565 -6573.
AMA StyleBrendan J. O’Brien, Deborah A. Neher, Eric D. Roy. Nutrient and Pathogen Suppression Properties of Anaerobic Digestates from Dairy Manure and Food Waste Feedstocks. Waste and Biomass Valorization. 2019; 11 (12):6565-6573.
Chicago/Turabian StyleBrendan J. O’Brien; Deborah A. Neher; Eric D. Roy. 2019. "Nutrient and Pathogen Suppression Properties of Anaerobic Digestates from Dairy Manure and Food Waste Feedstocks." Waste and Biomass Valorization 11, no. 12: 6565-6573.
Two desirable functions of healthy soil are nutrient cycling and pest suppression. We review relevant literature on the contributions of soil microarthropods to soil health through their intersecting roles in decomposition and nutrient cycling and direct and indirect suppression of plant pests. Microarthropods can impact soil and plant health directly by feeding on pest organisms or serving as alternate prey for larger predatory arthropods. Indirectly, microarthropods mediate the ability of crop plants to resist or tolerate insect pests and diseases by triggering induced resistance and/or contributing to optimal nutritional balance of plants. Soil fauna, including microarthropods, are key regulators of decomposition at local scales but their role at larger scales is unresolved. Future research priorities include incorporating multi-channel omnivory into food web modeling and understanding the vulnerability of soil carbon through global climate change models.
Deborah A. Neher; Mary E. Barbercheck. Soil Microarthropods and Soil Health: Intersection of Decomposition and Pest Suppression in Agroecosystems. Insects 2019, 10, 414 .
AMA StyleDeborah A. Neher, Mary E. Barbercheck. Soil Microarthropods and Soil Health: Intersection of Decomposition and Pest Suppression in Agroecosystems. Insects. 2019; 10 (12):414.
Chicago/Turabian StyleDeborah A. Neher; Mary E. Barbercheck. 2019. "Soil Microarthropods and Soil Health: Intersection of Decomposition and Pest Suppression in Agroecosystems." Insects 10, no. 12: 414.
Infections of the cow udder leading to mastitis and reducing milk quality are a critical challenge facing all dairy farmers. Mastitis may be linked to the ecological disruption of an endogenous mammary microbial community, suggesting an ecosystems approach to management and prevention of this disease. The teat end skin represents a first point of host contact with mastitis pathogens and may offer an opportunity for microbially mediated resistance to infection, yet we know little about the microbial community of teat end skin or its potential interaction with the microbial community of intramammary milk of organic dairy cattle. High-throughput sequencing of marker genes for bacterial and fungal communities was used to characterize the skin and milk microbiome of cows with both a healthy and infected gland (i.e., udder quarter) and to assess the sharing of microbial DNA between these tissue habitat sites. The mammary microbiome varied among cows, through time, and between skin and milk. Microbiomes of milk from healthy and infected quarters reflected a diverse group of microbial DNA sequences, though milk had far fewer operational taxonomic units (OTUs) than skin. Milk microbiomes of infected quarters were generally more variable than healthy quarters and were frequently dominated by a single OTU; teat end skin microbiomes were relatively similar between healthy and infected quarters. Commonly occurring genera that were shared between skin and milk of infected glands included Staphylococcus spp. bacteria and Debaryomyces spp. fungi. Commonly occurring genera that were shared between skin and milk of healthy glands included bacteria SMB53 (Clostridiaceae) and Penicillium spp. fungi. Results support an ecological interpretation of the mammary gland and the notion that mastitis can be described as a dysbiosis, an imbalance of the healthy mammary gland microbiome.
Tucker Andrews; Deborah A. Neher; Thomas R. Weicht; John W. Barlow. Mammary microbiome of lactating organic dairy cows varies by time, tissue site, and infection status. PLoS ONE 2019, 14, e0225001 .
AMA StyleTucker Andrews, Deborah A. Neher, Thomas R. Weicht, John W. Barlow. Mammary microbiome of lactating organic dairy cows varies by time, tissue site, and infection status. PLoS ONE. 2019; 14 (11):e0225001.
Chicago/Turabian StyleTucker Andrews; Deborah A. Neher; Thomas R. Weicht; John W. Barlow. 2019. "Mammary microbiome of lactating organic dairy cows varies by time, tissue site, and infection status." PLoS ONE 14, no. 11: e0225001.
Two desirable functions of healthy soil are nutrient cycling and pest suppression. We review recent literature on the contributions of soil microarthropods to soil health through their intersecting roles in decomposition and nutrient cycling and direct and indirect suppression of plant pests. Microarthropods can impact soil and plant health directly by feeding on pest organisms or serving as alternate prey for larger predatory arthropods, and indirectly, by mediating the ability of crop plants to resist or tolerate insect pests and diseases through interactions with the decomposition food web in support of plant nutrition. Soil fauna, including microarthropods, are key regulators of decomposition at local scales but their role at larger scales is unresolved. Future research priorities include the incorporation of multi-channel omnivory into food web modeling and understanding the vulnerability of our soil carbon to increased global temperatures.
Deborah A. Neher; Mary E. Barbercheck. Soil microarthropods and soil health: Intersection of decomposition and pest suppression. 2019, 1 .
AMA StyleDeborah A. Neher, Mary E. Barbercheck. Soil microarthropods and soil health: Intersection of decomposition and pest suppression. . 2019; ():1.
Chicago/Turabian StyleDeborah A. Neher; Mary E. Barbercheck. 2019. "Soil microarthropods and soil health: Intersection of decomposition and pest suppression." , no. : 1.
Anaerobic co-digestion of dairy manure and food wastes is increasing in the New England region of the United States because of policy measures intended to divert organic materials from landfills, reduce greenhouse gas emissions, and increase renewable biogas energy production. The sustainability of this approach depends on the management and valorization of remaining solid and liquid residues (i.e., digestates) after anaerobic digestion. Few studies have characterized digestates derived from combined dairy manure and food waste feedstocks. In this study, we analyzed screw-press separated liquid and solid digestates from 6 of 26 (23%) operational full-scale facilities in New England. We quantified multiple pools of nitrogen and phosphorus in these materials, with results suggesting that in most cases these nutrients largely exist in forms that can be recycled via slow-release fertilization, with smaller fractions in forms more easily lost to the environment. Furthermore, we found that solid digestates can inhibit mycelial growth of a common soilborne fungal pathogen, Rhizoctonia solani, suggesting potential to manage resident soil pathogens. Capitalizing on both nutrient recycling and pathogen suppression co-benefits will likely be useful in digestate valorization efforts.
Brendan J O'brien; Deborah A Neher; Eric D Roy. Nutrient and pathogen suppression properties of anaerobic digestates from dairy manure and food waste feedstocks. 2019, 1 .
AMA StyleBrendan J O'brien, Deborah A Neher, Eric D Roy. Nutrient and pathogen suppression properties of anaerobic digestates from dairy manure and food waste feedstocks. . 2019; ():1.
Chicago/Turabian StyleBrendan J O'brien; Deborah A Neher; Eric D Roy. 2019. "Nutrient and pathogen suppression properties of anaerobic digestates from dairy manure and food waste feedstocks." , no. : 1.
Anaerobic co-digestion of dairy manure and food wastes is increasing in the New England region of the United States because of policy measures intended to divert organic materials from landfills, reduce greenhouse gas emissions, and increase renewable biogas energy production. The sustainability of this approach depends on the management and valorization of remaining solid and liquid residues (i.e., digestates) after anaerobic digestion. Few studies have characterized digestates derived from combined dairy manure and food waste feedstocks. In this study, we analyzed screw-press separated liquid and solid digestates from 6 of 26 (23%) operational full-scale facilities in New England. We quantified multiple pools of nitrogen and phosphorus in these materials, with results suggesting that in most cases these nutrients largely exist in forms that can be recycled via slow-release fertilization, with smaller fractions in forms more easily lost to the environment. Furthermore, we found that solid digestates can inhibit mycelial growth of a common soilborne fungal pathogen, Rhizoctonia solani, suggesting potential to manage resident soil pathogens. Capitalizing on both nutrient recycling and pathogen suppression co-benefits will likely be useful in digestate valorization efforts.
Brendan J O'brien; Deborah A Neher; Eric D Roy. Nutrient and pathogen suppression properties of anaerobic digestates from dairy manure and food waste feedstocks. 2019, 1 .
AMA StyleBrendan J O'brien, Deborah A Neher, Eric D Roy. Nutrient and pathogen suppression properties of anaerobic digestates from dairy manure and food waste feedstocks. . 2019; ():1.
Chicago/Turabian StyleBrendan J O'brien; Deborah A Neher; Eric D Roy. 2019. "Nutrient and pathogen suppression properties of anaerobic digestates from dairy manure and food waste feedstocks." , no. : 1.
Aims The aim was to monitor the survival and persistence of E. coli in soil amended with compost from different manure sources. Method and Results Complex interactions of abiotic and biotic factors on E. coli survival were monitored in field experiment plots receiving randomly assigned compost treatments: dairy windrow, dairy vermicompost, poultry windrow, or no compost. Biomass, activity, and function of indigenous microbial communities in the composts and soils were measured concurrently to determine whether mechanisms of compost were driven by biotic or abiotic properties. Survival of E. coli persisted with poultry amendments but not in dairy or no compost treatments. Poultry compost contained more NH4‐N and a distinct microbial community compared to dairy and no compost treatments. A laboratory experiment performed on compost extracts suggested that E. coli survived better in extracts devoid of indigenous microbes as long as bioavailable nutrients were plentiful. Conclusions Dairy‐based composts are less likely to support E. coli survival than poultry‐based composts. Significance and Impact of the study Results aid in risk assessment of the use of different types of manure‐based compost and soil amendments in fruit and vegetable production by elucidating the roles of nutrient and microbial community composition on survival of E. coli in amended field soils. This article is protected by copyright. All rights reserved.
Deborah A. Neher; Anya J. Cutler; Thomas R. Weicht; Manan Sharma; Patricia D. Millner. Composts of poultry litter or dairy manure differentially affect survival of enteric bacteria in fields with spinach. Journal of Applied Microbiology 2019, 126, 1910 -1922.
AMA StyleDeborah A. Neher, Anya J. Cutler, Thomas R. Weicht, Manan Sharma, Patricia D. Millner. Composts of poultry litter or dairy manure differentially affect survival of enteric bacteria in fields with spinach. Journal of Applied Microbiology. 2019; 126 (6):1910-1922.
Chicago/Turabian StyleDeborah A. Neher; Anya J. Cutler; Thomas R. Weicht; Manan Sharma; Patricia D. Millner. 2019. "Composts of poultry litter or dairy manure differentially affect survival of enteric bacteria in fields with spinach." Journal of Applied Microbiology 126, no. 6: 1910-1922.
Reports of disease suppression by compost are inconsistent likely because there are no established standards for feedstock material, maturity age for application, and application rate. The overall goal of the study was to evaluate a suite of biological indicators for their ability to predict disease suppression. Indicators included both commercial available methods for compost stability (Solvita™, respiration) and metrics of soil ecology not yet adopted by the compost industry (e.g., ecoenzymes, nematode community index). Damping-off by Rhizoctonia solani on radish was chosen as a model system given its global importance, competitiveness affected by carbon quality, and lack of disease management options for organic production. Biological indicators were evaluated for their ability to consistently differentiate among curing process, maturity, and feedstock material as a function of disease severity of a seedling bioassay and a compost extract assay to test competition with R. solani growth. Compost processed as vermicompost and anaerobic digestate were more suppressive against R. solani than windrow or aerated static pile. Mature composts were more suppressive than immature components. Feedstocks containing dairy manure and/or hardwood bark tended to have suppressive qualities. In contrast, poultry manure-based components were conducive to disease. Microbial ecoenzymes active on chitin and cellulose and nematode community indices were better predictors of disease suppressiveness than microbial respiration. These indicators are quicker than plant bioassays and could be adopted as tools to certify commercial products.
Deborah A. Neher; Lynn Fang; Thomas R. Weicht. Ecoenzymes as Indicators of Compost to Suppress Rhizoctonia Solani. Compost Science & Utilization 2017, 25, 251 -261.
AMA StyleDeborah A. Neher, Lynn Fang, Thomas R. Weicht. Ecoenzymes as Indicators of Compost to Suppress Rhizoctonia Solani. Compost Science & Utilization. 2017; 25 (4):251-261.
Chicago/Turabian StyleDeborah A. Neher; Lynn Fang; Thomas R. Weicht. 2017. "Ecoenzymes as Indicators of Compost to Suppress Rhizoctonia Solani." Compost Science & Utilization 25, no. 4: 251-261.
Roads cause both chemical and physical disturbance at the time of creation and through the maintenance of the road. However, none have fully considered the extent of above- and below-ground impacts related to roads. Our study seeks to fill this gap with three objectives: (1) quantify differences in the nematode community by road-use intensity, (2) estimate distance of environmental impact of roads using nematode community indices, and (3) relate nematode communities to abiotic soil and above-ground plant communities for a relatively comprehensive environmental assessment of the spatial footprint of roads on the landscape. Soil and plant samples were co-located at six distances from the road edge (shoulder, sideslope, ditch, backslope, 10 m from forest edge, and 50 m from road crown) for each of 10 transects perpendicular to each of three road types (highways, two-lane paved, and gravel). There were differences in all nematode community measures based upon distance as a main effect, correlating with patterns of plant communities. Nematode community index values reflect increased disturbance closer to the road, particularly at the shoulder, with later ecological succession and a shift in the decomposer food web with increased distance from the road and in reference forest sites. In contrast, chemical properties of soil were influenced more by road type and the two-way interaction of road type and topography. Salt concentrations were greatest by two-lane paved roads, while heavy metal concentrations were greatest near highway roads. This study is one of the most comprehensive assessments of environmental impact by roads, providing data for accurate transportation system models. The results suggest that conscious design and management of the forest buffer and intentional inclusion of a ditch as a roadside feature may minimize pollutant movement and protect surrounding landscapes.
Deborah A. Neher; Kristin M. Williams; Sarah Lovell. Environmental indicators reflective of road design in a forested landscape. Ecosphere 2017, 8, e01734 .
AMA StyleDeborah A. Neher, Kristin M. Williams, Sarah Lovell. Environmental indicators reflective of road design in a forested landscape. Ecosphere. 2017; 8 (3):e01734.
Chicago/Turabian StyleDeborah A. Neher; Kristin M. Williams; Sarah Lovell. 2017. "Environmental indicators reflective of road design in a forested landscape." Ecosphere 8, no. 3: e01734.
Low-input methods for addressing economic and management challenges of plant pathogens and weed seeds will advance sustainable farming practices. Objective 1 was to demonstrate that U.S. National Organic Standards (NOS) for compost are sufficient to kill plant pathogens and weed seed. Known quantities of early blight inoculum (Alternaria brassicinae) and giant crab grass (Digitaria sanguinalis) seed were enclosed in bags and inserted into manure-based compost containing different sources of C: 1) manure–silage, 2) hay, 3) softwood, and 4) hardwood. Except for the manure–silage control, treatments represented C:N ratios prescribed by NOS. Bags were removed at five times during the compost process. Both pathogenicity and seed germination were reduced to zero by following NOS guidelines. Patterns of microbial enzyme activity illustrated that labile substrates were abundant in manure–silage and hay, but limited in softwood and hardwood treatments. For Objective 2, field trials were conducted at two farms. Compost treatments were applied after the first cultivation as mulch as follows: 1) manure–silage, 2) hay, and 3) hardwood. Non-mulched plots were used as bare controls. When compost was applied at a rate of 54.8 ton/ha (20 ton/acre), compost made with hardwood bark suppressed severity of early blight disease more than compost made with softwood, hay or manure–silage.
Deborah A. Neher; Thomas R. Weicht; Patrick Dunseith. Compost for Management of Weed Seeds, Pathogen, and Early Blight on Brassicas in Organic Farmer Fields. Agroecology and Sustainable Food Systems 2014, 39, 3 -18.
AMA StyleDeborah A. Neher, Thomas R. Weicht, Patrick Dunseith. Compost for Management of Weed Seeds, Pathogen, and Early Blight on Brassicas in Organic Farmer Fields. Agroecology and Sustainable Food Systems. 2014; 39 (1):3-18.
Chicago/Turabian StyleDeborah A. Neher; Thomas R. Weicht; Patrick Dunseith. 2014. "Compost for Management of Weed Seeds, Pathogen, and Early Blight on Brassicas in Organic Farmer Fields." Agroecology and Sustainable Food Systems 39, no. 1: 3-18.
Compost production is a critical component of organic waste handling, and compost applications to soil are increasingly important to crop production. However, we know surprisingly little about the microbial communities involved in the composting process and the factors shaping compost microbial dynamics. Here, we used high-throughput sequencing approaches to assess the diversity and composition of both bacterial and fungal communities in compost produced at a commercial-scale. Bacterial and fungal communities responded to both compost recipe and composting method. Specifically, bacterial communities in manure and hay recipes contained greater relative abundances of Firmicutes than hardwood recipes with hay recipes containing relatively more Actinobacteria and Gemmatimonadetes. In contrast, hardwood recipes contained a large relative abundance of Acidobacteria and Chloroflexi. Fungal communities of compost from a mixture of dairy manure and silage-based bedding were distinguished by a greater relative abundance of Pezizomycetes and Microascales. Hay recipes uniquely contained abundant Epicoccum, Thermomyces, Eurotium, Arthrobotrys, and Myriococcum. Hardwood recipes contained relatively abundant Sordariomycetes. Holding recipe constant, there were significantly different bacterial and fungal communities when the composting process was managed by windrow, aerated static pile, or vermicompost. Temporal dynamics of the composting process followed known patterns of degradative succession in herbivore manure. The initial community was dominated by Phycomycetes, followed by Ascomycota and finally Basidiomycota. Zygomycota were associated more with manure-silage and hay than hardwood composts. Most commercial composters focus on the thermophilic phase as an economic means to insure sanitation of compost from pathogens. However, the community succeeding the thermophilic phase begs further investigation to determine how the microbial dynamics observed here can be best managed to generate compost with the desired properties.
Deborah A. Neher; Thomas R. Weicht; Scott T. Bates; Jonathan W. Leff; Noah Fierer. Changes in Bacterial and Fungal Communities across Compost Recipes, Preparation Methods, and Composting Times. PLOS ONE 2013, 8, e79512 .
AMA StyleDeborah A. Neher, Thomas R. Weicht, Scott T. Bates, Jonathan W. Leff, Noah Fierer. Changes in Bacterial and Fungal Communities across Compost Recipes, Preparation Methods, and Composting Times. PLOS ONE. 2013; 8 (11):e79512.
Chicago/Turabian StyleDeborah A. Neher; Thomas R. Weicht; Scott T. Bates; Jonathan W. Leff; Noah Fierer. 2013. "Changes in Bacterial and Fungal Communities across Compost Recipes, Preparation Methods, and Composting Times." PLOS ONE 8, no. 11: e79512.
Previous reports suggest that fungivorous nematodes are the only trophic group in forest soils affected by elevated CO2. However, there can be ambiguity within trophic groups, and we examined data at a genus level to determine whether the conclusion remains similar. Nematodes were extracted from roots and soil of loblolly pine (Pinus taeda) and sweet gum (Liquidambar styraciflua) forests fumigated with either ambient air or CO2-enriched air. Root length and nematode biomass were estimated using video image analysis. Most common genera included Acrobeloides, Aphelenchoides, Cephalobus, Ditylenchus, Ecphyadorphora, Filenchus, Plectus, Prismatolaimus, and Tylencholaimus. Maturity Index values and diversity increased with elevated CO2 in loblolly pine but decreased with elevated CO2 in sweet gum forests. Elevated CO2 treatment affected the occurrence of more nematode genera in sweet gum than loblolly pine forests. Numbers were similar but size of Xiphinema decreased in elevated CO2. Abundance, but not biomass, of Aphelenchoides was reduced by elevated CO2. Treatment effects were apparent at the genus levels that were masked at the trophic level. For example, bacterivores were unaffected by elevated CO2, but abundance of Cephalobus was affected by CO2 treatment in both forests.
Deborah A. Neher; Thomas R. Weicht. Nematode Genera in Forest Soil Respond Differentially to Elevated CO2. Journal of Nematology 2013, 45, 214 -222.
AMA StyleDeborah A. Neher, Thomas R. Weicht. Nematode Genera in Forest Soil Respond Differentially to Elevated CO2. Journal of Nematology. 2013; 45 (3):214-222.
Chicago/Turabian StyleDeborah A. Neher; Thomas R. Weicht. 2013. "Nematode Genera in Forest Soil Respond Differentially to Elevated CO2." Journal of Nematology 45, no. 3: 214-222.
The spatial extent of the transported materials from three road types was studied in forest soil and vegetative communities in Vermont. Hypotheses were two-fold: 1) soil chemical concentrations above background environment would reflect traffic volume and road type (highway>2-lane paved>gravel), and 2) plant communities close to the road and near roads with greater traffic will be disturbance-tolerant and adept at colonization. Soil samples were gathered from 12 randomly identified transects for each of three road types classified as "highway," "two-lane paved," and "gravel." Using GIS mapping, transects were constructed perpendicular to the road, and samples were gathered at the shoulder, ditch, backslope, 10 m from the edge of the forest, and 50 m from road center. Sample locations were analyzed for a suite of soil elements and parameters, as well as percent area coverage by plant species. The main effects from roads depended on the construction modifications required for a roadway (i.e., vegetation clearing and topography modification). The cleared area defined the type of plant community and the distance that road pollutants travel. Secondarily, road presence affected soil chemistry. Metal concentrations (e.g., Pb, Cd, Cu, and Zn) correlated positively with road type. Proximity to all road types made the soils more alkaline (pH 7.7) relative to the acidic soil of the adjacent native forest (pH 5.6). Roadside microtopography had marked effects on the composition of plant communities based on the direction of water flow. Ditch areas supported wetland plant species, greater soil moisture and sulfur content, while plant communities closer to the road were characteristic of drier upland zones. The area beyond the edge of the forest did not appear to be affected chemically or physically by any of the road types, possibly due to the dense vegetation that typically develops outside of the managed right-of-way.
Deborah A. Neher; David Asmussen; Sarah Lovell. Roads in northern hardwood forests affect adjacent plant communities and soil chemistry in proportion to the maintained roadside area. Science of The Total Environment 2013, 449, 320 -327.
AMA StyleDeborah A. Neher, David Asmussen, Sarah Lovell. Roads in northern hardwood forests affect adjacent plant communities and soil chemistry in proportion to the maintained roadside area. Science of The Total Environment. 2013; 449 ():320-327.
Chicago/Turabian StyleDeborah A. Neher; David Asmussen; Sarah Lovell. 2013. "Roads in northern hardwood forests affect adjacent plant communities and soil chemistry in proportion to the maintained roadside area." Science of The Total Environment 449, no. : 320-327.
Nematodes are aquatic organisms that depend on thin water films to live and move within existing pathways of soil pores of 25-100 mum diameter. Soil nematodes can be a tool for testing ecological hypotheses and understanding biological mechanisms in soil because of their central role in the soil food web and linkage to ecological processes. Ecological succession is one of the most tested community ecology concepts, and a variety of nematode community indices have been proposed for purposes of environmental monitoring. In contrast, theories of biogeography, colonization, optimal foraging, and niche partitioning by nematodes are poorly understood. Ecological hypotheses related to strategies of coexistence of nematode species sharing the same resource have potential uses for more effective biological control and use of organic amendments to foster disease suppression. Essential research is needed on nematodes in natural and agricultural soils to synchronize nutrient release and availability relative to plant needs, to test ecological hypotheses, to apply optimal foraging and niche partitioning strategies for more effective biological control, to blend organic amendments to foster disease suppression, to monitor environmental and restoration status, and to develop better predictive models for land-use decisions.
Deborah A. Neher. Ecology of Plant and Free-Living Nematodes in Natural and Agricultural Soil. Annual Review of Phytopathology 2010, 48, 371 -394.
AMA StyleDeborah A. Neher. Ecology of Plant and Free-Living Nematodes in Natural and Agricultural Soil. Annual Review of Phytopathology. 2010; 48 (1):371-394.
Chicago/Turabian StyleDeborah A. Neher. 2010. "Ecology of Plant and Free-Living Nematodes in Natural and Agricultural Soil." Annual Review of Phytopathology 48, no. 1: 371-394.
Details about a particular book
D. A. Neher; B. J. Darby. General community indices that can be used for analysis of nematode assemblages. Nematodes as environmental indicators 2009, 107 -123.
AMA StyleD. A. Neher, B. J. Darby. General community indices that can be used for analysis of nematode assemblages. Nematodes as environmental indicators. 2009; ():107-123.
Chicago/Turabian StyleD. A. Neher; B. J. Darby. 2009. "General community indices that can be used for analysis of nematode assemblages." Nematodes as environmental indicators , no. : 107-123.