College of Agriculture & Natural Resources

Permanent URI for this communityhttp://hdl.handle.net/1903/1598

The collections in this community comprise faculty research works, as well as graduate theses and dissertations.

Browse

Subject: search.filters.subject.compost

Search Results

Now showing 1 - 5 of 5
  • Thumbnail Image
    Item
    THE USE OF ORGANIC WASTE PRODUCTS AS SOIL AMENDMENTS FOR TURFGRASS ESTABLISHMENT: EFFECTS AND REGULATORY INFLUENCES
    (2024) Morash, Jennifer Dawn; Lea-Cox, John; Plant Science and Landscape Architecture (PSLA); Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)
    The use of organic waste products as soil amendments in highly disturbed urban soil is poised to grow due to rising fertilizer costs, waste-management issues, and greater emphasis on creating sustainable circular economies. Despite the advantages of using waste products as organic amendments to enhance fertility, their incorrect use may result in short-term unintended consequences such as nutrient losses or the immobilization of plant-essential nutrients, which could diminish efforts to establish vegetation on disturbed soil. To avoid these consequences, transportation authorities – cited as the largest users of compost in some states – have implemented measures to improve product specifications. This research details the efforts of one such organization, the Maryland Department of Transportation State Highway Administration (MDOT SHA), and the results of an initiative to increase the quality of manufactured topsoil and compost use through agency topsoil specifications. After determining which products were most likely to be incorporated into manufactured topsoil (finely shredded wood mulch and composted leaf yard waste), two greenhouse microcosm experiments were conducted to evaluate plant growth responses and the efficiency of nutrient uptake compared to leachate losses when those amendments were used in accordance with MDOT SHA specifications. Composted yard waste provided excellent results while wood mulch suppressed growth in the short-term studies. A biosolids treatment was included in the experiments due to widespread availability and growing interest. Biosolids improved soil fertility and plant growth. However, the difference between nitrogen (N) uptake and leachate mass losses required a second set of experiments, to quantify the effects of four biosolids amendments on plant growth, nutrient uptake, and leachate losses. Treatments were applied at the rate recommended by UMD for turfgrass establishment (2.54 cm, incorporated) and included fresh biosolids, biosolids that were stockpiled for two years, two blended products made from either the fresh or aged biosolids and fine wood mulch, an inorganic fertilizer, and a control. Aging and wood fines reduced N leaching losses but at the expense of N inputs to soil. The cumulative N leachate mass loss from the new biosolids treatment was 63 times greater than the cumulative fertilizer total. Aging did not reduce phosphorus (P) leaching losses but wood fines did by diluting the concentration of P in blends. However, biosolids mostly retained P in the soil and cumulative fertilizer losses were 2 times higher. Overall, growth measurements showed that biosolids enhanced growth during the first and second growing seasons. However, based on the results of this research, 2.54 cm of pure biosolids is not required to enhance turfgrass establishment. An application of 1.27 cm of pure biosolids or 2.54 cm of a biosolid/wood fine blend should provide comparable enhanced turfgrass growth results while reducing overall nutrient leachate losses.
  • Thumbnail Image
    Item
    Influence of Manure Application on the Soil Bacterial Microbiome in Integrated Crop-Livestock Farms in Maryland
    (MDPI, 2021-12-15) Peng, Mengfei; Tabashsum, Zajeba; Millner, Patricia; Parveen, Salina; Biswas, Debabrata
    As a traditional agricultural system, integrated crop-livestock farms (ICLFs) involve the production of animals and crops in a shared environment. The ICLFs in the mid-Atlantic region of the United States practice sustainable manure aging or composting processes to provide an on-farm source of soil amendment for use as natural fertilizer and soil conditioner for crop production. However, crop fertilization by soil incorporation of aged manure or compost may introduce different microbes and alter the soil microbial community. The aim of this study was to characterize the influence of aged or composted manure application on the diversity of soil bacterial community in ICLFs. Soil samples from six ICLFs in Maryland were collected before (pre-crop) and during the season (2020–2021) and used to analyze soil bacterial microbiome by 16S rDNA sequencing. Results showed that both phylum- and genus-level alterations of soil bacterial communities were associated with amendment of aged or composted manure. Particularly, Proteobacteria and Actinobacteria were enriched, while Acidobacteria, Bacteroidetes, Planctomycetes, Firmicutes, and Chloroflexi were reduced after manure product application. Meanwhile, the relative abundance of Bacillus was decreased, while two zoonotic pathogens, Salmonella and Listeria, were enriched by manure amendments. Overall, animal manure amendment of soil increased the phylogenetic diversity, but reduced the richness and evenness of the soil bacterial communities. Although manure composting management in ICLFs benefits agricultural sustainable production, the amendments altered the soil bacterial communities and were associated with the finding of two major zoonotic bacterial pathogens, which raises the possibility of their potential transfer to fresh horticultural produce crops that may be produced on the manured soils and then subsequently consumed without cooking.
  • Thumbnail Image
    Item
    Biosolids and Compost For Urban Soil Restoration and Forestry
    (2022) Keener, Emily Cathryn; Pavao-Zuckerman, Mitchell A; Environmental Science and Technology; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)
    Elements of urban soil quality such as compaction and low organic matter are underexamined, important challenges to urban afforestation. In this Beltsville, Maryland field experiment, I examined biosolids and compost as amendments to improve soil quality and planted tree survival in a degraded urban proxy soil and identified correlations between soil properties and tree survival. Organic amendments increased organic matter content, decreased bulk density, and had no effect on tree survivorship compared to controls. Effects on soil were more profound and lasting with compost than with biosolids. Soil organic matter and bulk density were correlated with tree survival early in the study and microbial respiration was correlated with tree survival throughout the study. High tree mortality was driven by transplant shock, limiting insights from tree response data. This study highlights the importance of soil quality and good planting practices in future research.
  • Thumbnail Image
    Item
    EFFECT OF COMPOST ON THE MICROCLOVER ESTABLISHMENT AND USE OF COMPOST AND MICROCLOVER TO REDUCE LAWN NUTRIENT RUNOFF
    (2016) Xiao, Xiayun; Carroll, Mark; Plant Science and Landscape Architecture (PSLA); Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)
    High volume compost incorporation can reduce runoff from compacted soils but its use also associated with elevated N and P concentrations in runoff making it difficult to assess if this practice will reduce nutrient loading of surface waters. Additionally, little is known about how this practice will effect leguminous species establishment in lawns as means to reduce long term fertilizer use. When 5 cm of compost was incorporated into soil a reduction in runoff of 40 and 59% was needed for N and P losses from a tall fescue + microclover lawn to be equivalent to a non-compost amended soil supporting a well fertilized tall fescue lawn. Use of compost as a soil amendment resulted in quicker lawn establishment and darker color, when compared to non-amended soil receiving a mineral fertilizer. Biosolid composts containing high amounts ammonium severely reduce the establishment of clover in tall fescue + micrclover seed mixture.
  • Thumbnail Image
    Item
    Local lettuce: heat tolerant romaine cultivars and vermicompost soil amendment to increase sustainability in the Mid-Atlantic
    (2014) Wallis, Anna Elizabeth; Walsh, Chris S; Plant Science and Landscape Architecture (PSLA); Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)
    Local production of lettuce in the Mid-Atlantic utilizing heat-tolerant romaine cultivars and vermicompost soil amendment has the potential to significantly increase sustainability of agriculture. Heat tolerant cultivars would facilitate season extension into the summer. Vermicompost, compost produced using earthworms, may increase yield and quality of lettuce crops. This research tested a system incorporating these two practices. Success was assessed on lettuce yield and quality of lettuce across three seasons (spring, summer, and fall) and food safety risk of vermicompost. Several of the heat tolerant cultivars showed marketing potential when grown in the summer. Vermicompost did not significantly increase lettuce performance, but trends indicate that it may help, especially at higher rates. No food safety risk was associated with tested materials.