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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

The fate of manure phosphorus during production and harvest of turfgrass sod

McDonald, Brandon Tieman 29 August 2005 (has links)
Removal of manure from dairies to sites less prone to point-source nutrient pollution is an option for dealing with dairy confined animal feeding operation wastes. Applications of dairy manure waste to turfgrass sod can be an environmentally sound approach because both plant matter and soil are removed during harvest (Vietor et al., 2002). Field scale research was conducted on a pair of adjacent, 1.42 ha Tifway bermudagrass fields on a fine-textured clay soil to investigate the fate of manure phosphorus (P) from composted dairy manure applications. Both fields received equal rates of supplemental nitrogen fertilizer but one was treated with composted dairy manure. The treated field received 75 kg ha-1 P during the first crop. After harvest, 127 kg ha-1 P was applied to the second crop. Once reestablished, this crop was harvested. Surface layer sod and subsurface soil were frequently sampled on a grid pattern from each field and analyzed to monitor soil P. Both plant extractable and total P analyses were used. It was determined that a sod harvest couldeffectively remove all of the applied manure P. Below the sod layer, there were no increases in soil P as a result of the composted dairy manure treatments, indicating that P leaching did not occur. Phosphorus runoff during rain events or irrigation was monitored by members of the Department of Biological and Agricultural Engineering. It was reported that more P was lost in runoff from the compost treated field than the untreated field. Cumulative water infiltration rate, soil bulk density, and plant available water holding capacity of the soil were tested to determine if the composted dairy manure treatments affected these soil physical properties. The only significant change was an increase in plant available water holding capacity on the surface layer of the treated field. An economic analysis was performed using actual financial data from the project. A scenario was created to investigate the feasibility of a dairy farm profitably adding a small turfgrass sod enterprise to its operation. It was determined that a sod field enterprise could be moderately to highly profitable for a dairy.
2

Maximising the performance of sports turf

Canaway, Patrick Michael January 1994 (has links)
Research was carried out on four main subject areas: playing quality of natural turf; establishment; nitrogen nutrition and stabilisation ofsand rootzones. Apparatus and test methods for determining playing quality are described and procedures for the development of standards for playing quality measures are given. A theoretical analysis of the factors governing playing quality was undertaken which showed that natural turf must be considered in terms of the plant and soil constituents and the manner in which these interact, especially in response to wear. The soil factor grouping is shown to be the most important influence on playing quality, primarily through its effect on moisture retention and throughput. A large-scale field experiment was carried out in order to investigate the effect of five different constructional techniques on playing quality and other aspects of turf performance. Constructional types included: pipe-drainage, slitdrainage, slit-drainage with a 25mm sand layer, a sand carpet and a sand profile construction. The results showed that the sand-based constructions provided the best playing quality but that potential numbers of days lost due to the presence of standing water decreased with increasing constructional sophistication. A review of playing quality of fine turf was carried out and an experiment on ball roll characteristics of five turfgrass specieswas undertaken which showed significant differencesamong species. Two experiments on the establishment of turf using different types of seed and sod were carried out, whose objective was to determine the effects of these experimental treatments on the playing quality, ground cover and water infiltration rate of playing surfaces for both football and golf. Experimental treatments included grades of mature turf, juvenile turf and seed. The most notable finding was the dramatic reduction in water infiltration rate where mature turfwas used for establishment. This was ascribed to a combination of organic and mineral matter imported along with the turf causing blockage of soil macropores and hence reducing water infiltration rate. The effect offertiliser nitrogen on the response of Lolium perenne turf grown on a PruntyMulqueen sand carpet rootzone was studied a field experiment which was subjected to football-type artificial wear treatments during two playing seasons. Measures included ground cover under wear and playing quality. In the case of ground cover and player traction responses to nitrogen showed distinct optima particularly during wear. Ball rebound resilienceand hardness showed no such response. Finally an experiment on the stabilisation ofsand rootzones for sport was carried out the objective of which was to study the effect of artificially strengthening a sand rootzone using randomly oriented tensile inclusions {Netlon mesh elements}. Three different rates of mesh elements, two different sizes and establishment using two types of turf were studied in a field experiment. Mesh element inclusion was found to increase water infiltration rate, traction and hardness. Turf treated by washing to remove adhering soil prior to laying also gave higher infiltration rates and, in addition, affected playing quality.
3

Factors Contributing to Development of Salinity Problems in Turf

Brown, Paul, Walworth, Jim 08 1900 (has links)
8 pp. / The bulletin reviews the factors contributing to the development of salinity and sodium problems in desert turfgrass systems. Key factors include water restrictions, poor water quality, irrigation management, drought and poor soil structure.
4

Management of nitrogen and composted biosolids to cycle nutrients and enhance environmental quality during production and after transplanting turfgrass sod

Schnell, Ronnie Wayne 15 May 2009 (has links)
Land application of large, volume-based rates of municipal biosolids (MB) enhances soil physical properties and provides an alternative to disposal in landfills. Yet, topdressing or incorporation of the volume-based rates can increase non-point source losses of sediment and nutrients from excavated soils to surface waters. Research objectives were developed to evaluate the options for cycling of MB through turfgrass sod during production and after transplanting. The first objective was to compare the production of Tifway bermudagrass sod between fields grown with and without MB under increasing rates of supplemental fertilizer N. The second objective was to compare runoff losses between soils constructed with and without MB before planting to sprigs or sod transplanted from turfgrass grown in soil with and without incorporation of MB. Incorporation of 25% by volume of MB in soil enhanced (p < 0.001) turfgrass coverage of the soil surface compared to soil without MB. In addition, amending soil with MB reduced wet and dry sod weights (p < 0.001) and increased soil water content (p < 0.001) at harvest compared to sod without MB. Runoff concentrations and mass loss of total dissolved P (TDP) were significantly greater (P=0.001) for MB-amended compared to un-amended sod. In addition, a linear relationship (R2 = 0.94) was observed between water extractable soil P within the 0- to 2-cm depth and concentrations and mass loss of TDP in runoff. Similarly, runoff loss of NO3-N was greater (P = 0.05) for soil mixed with 25% by volume of MB than soil alone and variation of NO3-N loss among treatments was directly related to soil NO3-N concentration within the 0- to 5-cm depth. In contrast, runoff concentrations of NH4-N were directly related to inputs of N from turf clippings returned to soil rather than soil NH4-N concentrations. Total Kjeldahl N (TKN) concentration in runoff was unrelated to soil N concentrations, but was linearly related to mass loss of sediment in runoff. Transplanted sod reduced sediment loss compared to sprigged soil during turfgrass establishment and MB-amended soil reduced sediment loss compared to soil without MB. In addition, the MB imported in sod or incorporated in soil before sprigging increased soil organic carbon and mean soil water content compared to sod or soil without MB over a 92 day period. Incorporation of MB within soil prior to planting fertilizer grown turfgrass sod enhanced water conservation and reduced nutrient loss compared to planting MB-grown sod on un-amended soils.
5

Influence of nitrogen, reduced irradience and biostimulants on turfgrass growth, superoxide dismutase content and chlorphyll fluorescence

Doak, Samuel O. 18 May 2007 (has links)
Biostimulants (BIOS) are non-mineral substances that, when exogenously applied in very small quantities, stimulate the metabolic activity of plants. Past research with biostimulants has not included differing levels of nitrogen fertility or shade as variables. The research presented was designed to explore some interactions between biostimulants and nitrogen fertility on turfgrass grown under several light conditions. / Master of Science
6

Financial analysis of turfgrass production in Mississippi

Xu, Zhen 09 August 2008 (has links)
Interest in commercial sod production in Mississippi has increased steadily during the past years. The short and intermediate outlook for commercial turfgrass sod production in Mississippi appears strong, given current and expected population growth and steady business, industrial and infrastructure construction. The purpose of this study is to determine current production practices, marketing methods, and associated costs of production for the key types of turfgrass produced in Mississippi. This study also evaluated the financial feasibility of different model turfgrass farms at alternative equity positions. The results of this study indicated that it is financially feasible to produce turfgrass in 310-acre farms and 160-acre farms whereas investments in small farms fail to generate adequate cash flows during the seven year planning horizon. In addition, turfgrass operations exhibited substantial economies of size.
7

Identification of the causes of dry patch of fine sports turf in the UK

York, Catherine Adele January 1995 (has links)
No description available.
8

Competitive Effects of Perennial Ryegrass and Chewings Fescue on Bermudagrass Seed Establishment

Gooch, C. Bryan 21 May 1998 (has links)
Perennial ryegrass (Lolium perenne L.) is widely used as a fairway turf on golf courses throughout the transition zone. The transition zone represents the geographical areas between the temperate and subtropical climates, where neither warm season nor cool season grasses are well adapted. The late-spring establishment of seeded bermudagrass could potentially enhance summer quality of a perennial ryegrass fairway during periods of extreme summer stress. Studies were conducted over two years on both perennial ryegrass and Chewings fescue (Festuca rubra L. ssp. commutata Gaud.) areas to assess the competitive effects of each species on bermudagrass seed establishment. The use of fungicides, herbicides and a plant growth regulator, as well as cultivation treatment prior to seeding, were evaluated for their effects on bermudagrass establishment, turfgrass quality, disease incidence and summer annual grass control. Turfgrass treated with preventative fungicide applications of propiconazole and chlorothalonil maintained high density and turf quality which inhibited successful establishment of bermudagrass during either year. Bermudagrass establishment in 1996 was moderately successful in plots not treated with fungicides; however, due to disease severity, turfgrass quality was unacceptable. MSMA applications did not influence turfgrass quality or bermudagrass establishment. Crabgrass populations were too low to ascertain the efficacy of either MSMA (1996) or oxadiazon (1997) on summer annual grass control. Oxadiazon followed by activated charcoal prior to bermudagrass seeding did not adversely affect bermudagrass establishment. In 1996, trinexapac-ethyl slightly enhanced bermudagrass seed establishment, but the competitiveness of perennial ryegrass prohibited establishment success. During 1997, glyphosate was evaluated as a means of eliminating competition and increasing bermudagrass establishment. Glyphosate applied in small strips across existing stands of perennial ryegrass and Chewings fescue significantly increased bermudagrass establishment. Preplant aerification and vertical mowing increased bermudagrass establishment, but slightly reduced turfgrass quality. Overall, bermudagrass establishment into existing stands of turfgrass was successful only where glyphosate was strip-treated over plots to eliminate competition or under circumstances where disease pressure reduced competition from the existing turfgrass. / Master of Science
9

THE EFFECT OF NITROGEN APPLICATION TIMING ON PLANT AVAILABLE PHOSPHORUS

Horner, Emily Renee 24 June 2008 (has links)
No description available.
10

Estimation of visual quality and canopy characteristics of turfgrass using spectral reflectance and digital imagery

Lee, Hyeonju January 1900 (has links)
Master of Science / Department of Horticulture, Forestry, and Recreation Resources / Dale J. Bremer / Radiometric methods may provide more objective and quantitative assessments of turf quality and density than visual ratings and may be useful in measuring green leaf area index (LAI), aboveground biomass, and chlorophyll concentration. This three-year study was conducted near Manhattan, KS to examine: 1) relationships between canopy reflectance and visual quality and density ratings in four cool-season grasses tall fescue (Festuca arundinacea Schreb.), Kentucky bluegrass (Poa pratensis L.) and two hybrid bluegrasses (HBG); 2) effects of species, mowing height, and irrigation deficit on relationships between visual quality and reflectance; 3) comparisons of visual quality with reflectance and digital images of individual plots; and 4) relationships of LAI, aboveground biomass, and chlorophyll concentration with canopy reflectance in the same four grasses and in perennial ryegrass (Lolium perenne), zoysiagrass (Zoysia japonica Stued.), and bermudagrass [Cynodon dactylon (L.) Pers.]. Reflectance was strongly correlated with visual ratings in the normalized difference vegetation index (NDVI, [935-661]/[935+661] nm, r = 0.88), the near infrared to red (NIR/R [935/661] nm, r = 0.83), Stress1 (706/760 nm, r= 0.84), and Stress2 (706/813 nm, r= 0.70) ratios and at wavelengths 613 (r= 0.74) and 661 nm (r = 0.80), but correlations varied among years at each wavelength and vegetation index. For density, highest correlations were in NDVI (r=0.86), R661 (r=-0.84), and Stress2 (r=-0.82). Regressions between reflectance and quality and density ratings indicated cultivar- and mowing height-specific models. Irrigation-deficit strongly affected reflectance in KBG and both HBG but not in TF, indicating greater sensitivity to drought of bluegrasses than TF. Digital images indicated strong correlations between percentage green cover and visual quality (r=0.89). However, wide ranges in visual quality were observed in plots with similar green cover or NDVI for reasons that are not apparent. Correlations of LAI, aboveground biomass, and chlorophyll concentration with reflectance were strong in some species at different wavelengths and ratios. Results indicated both potential and limitations in using spectral reflectance to estimate turfgrass canopy characteristics.

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