Thesis--Auburn University, 2008. / Abstract. Vita. Includes bibliographical references (p. 80-89).

Thesis (Ph.D.)--Kent State University, 2009. / Title from PDF t.p. (viewed April 14, 2010). Advisor: Mark W. Kershner. Keywords: biodiversity; nitrogen; fertilization; plant litter; trophic dynamics; epigeal community. Includes bibliographical references.

Thesis (M.S.)--University of Wisconsin--Madison, 1973. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thesis (M.S.)--University of Kentucky, 2006. / Title from document title page (viewed on August 22, 2006). Document formatted into pages; contains: vi, 79 p. : ill. Includes abstract and vita. Includes bibliographical references (p. 71-78).

Thesis (Ph. D.)--University of Washington, 2007. / Vita. Includes bibliographical references (leaves 119-130).

Thesis (M.S.)--Humboldt State University, 2006. / Includes bibliographical references (leaves 67-72). Also available via Humboldt Digital Scholar.

Litterfall in the UBG Research Forest was collected from traps randomly-placed in each of five half-acre plots of twelve year old Coastal Douglas fir of spacings ranging from 3 x 3 to 15 x 15 feet. Collections were also made from a half-acre plot of 3 x 3 feet spaced eleven year old western hemlock, and from an older, thinned natural stand of western red cedar and western hemlock. Forest floor accumulations and soil samples from each plot were also collected and analysed. The amount of litterfall in the Douglas fir spacing plots showed that the denser the stand the greater was the litterfall. The percentage of litter from broadleaved species present was in increasing order from the 3 x 3 to the 15 x 15 feet Douglas fir plots. The amount of litterfall in the Douglas fir was about 3,000 kg/ha more than that in the western hemlock plot of the same spacing. The litterfall in the cedar-hemlock stand showed a large amount of cones and twigs, but was not greater than the litterfall collected from the denser plantations of Douglas fir. It should be noted that the 3x3 and 6x6 feet Douglas fir plots of this study gave a much greater litterfall than the values reported by other authors for this species. However, judging from the literature, comparable data for stands of this age and density are not available. Since the variation of litterfall within a plot was very great, the number of traps needed will have to be increased to attain a precision of ± 10 gm at 5% probability level for an annual collection. The amount of forest floor decreased as spacing widened. It was shown statistically that two groups of plots existed: one with associated vegetation (12 x 12 and 15 x 15 feet) and the other without (3x3 and 6x6 feet plots). The weight of forest floor of western hemlock was less than that of Douglas fir of the same spacing. The weights of forest floor obtained in this study were well below the figures given by other authors in this field. The index of forest floor turnover, calculated from the ratio of litter-fall/forest floor showed that the closer-spaced plantations had a higher ratio than the wider-spaced. This suggests that faster circulation of nutrient elements is going on in the stand with a full canopy than in a more widely spaced stand. The chemical contents of the litterfall and forest floor were determined on composite samples from each plot. Nutrient concentration in litterfall and forest floor did not vary with spacing in the Douglas fir plots. The ground vegetation layer found only under the wider Douglas fir spacings showed greater concentration of phosphorus and potassium than the litter or forest floor of all the spacings. The calcium concentration in the western hemlock and cedar-hemlock plots was higher than that found in the Douglas fir plots, but phosphorus was found to be lower. However, the total amount of nutrients in litterfall and in forest floor under differently spaced Douglas fir plantations followed a distinct pattern: a higher content was present in the denser and lower in the wider plots. No clear relationship between litterfall or forest floor accumulations and growth as measured so far was observed. The importance of soil physical properties in affecting growth should be considered more closely, because the plots were different in soil texture and probably in other physical characteristics. / Forestry, Faculty of / Graduate

I investigated the role of a flood in particulate organic matter (POM) dynamics of the Little Tennessee river/floodplain ecosystem in western North Carolina, USA. I measured litter inputs, leaf breakdown, floodplain litter, and aboveground herbaceous net primary production at 12 sites. Annual litter inputs (274-625 g m-2 y-1) were typical of a temperate deciduous forest, but lower than other floodplain forests in the eastern United States. Mean aboveground herbaceous net primary production ranged from 61-439 g m-2 y-1 and leaf breakdown rates of 4 tree species ranged from 0.001-0.010 d-1. Following a flood on 8 January 1998, sites were separated into three inundation classes: inundated, partially-inundated, and non-inundated. Sites inundated by a January flood had significantly less forest floor leaf litter and coarse woody debris after the flood. There was no significant change at the partially-inundated or non-inundated sites. In addition, there was no significant difference in herbaceous material between pre- and post-flood collections for any inundation classes. Litter input, leaf breakdown, and floodplain litter standing crop data suggest that flood entrainment of POM from the floodplain of Little Tennessee River is a source of POM to the active channel. The impact of floods on the floodplain POM dynamics, however, is highly dependent on the time of year and magnitude of the flood, and on the structure of floodplain tree assemblages, which is strongly influenced by anthropogenic land use. Compared to direct litterfall and instream primary production, the floodplain may be a small annual source of POM for the river. / Master of Science

No description available.

Despite high volumes of manure production in the Shenandoah Valley, there are still areas of forage production in the Shenandoah Valley that are nutrient deficient, because manures have traditionally been applied to higher value row crops. Furthermore, anecdotal reports have suggested that application of poultry litter to pastureland may increase the abundance of weeds. This study was conducted to compare the effects of poultry litter and inorganic fertilizers on soil fertility, aboveground botanical composition and soil seed bank composition of established mixed naturalized pastures. Two sites each had the following treatments applied for two consecutive years: 1) split application of litter: 3.36 Mg ha-1 in spring and 3.36 Mg ha-1 in summer; 2) inorganic fertilizer at same N, P and K rates as Trt. No. 1; 3) single application of litter: 6.72 Mg ha-1 in spring; 4) inorganic fertilizer at same N, P and K rates as Trt. No. 3; 5) unfertilized control. Forage yield, soil pH, Mehlich 1 P (M1P), P balance, water soluble phosphorus (WSP), shifts in aboveground botanical composition, seed bank composition, and species richness (SPR) were monitored during this experiment. In addition, we examined whether poultry litter carries germinable weed seeds that can be transferred to forage systems after application. On average, soil pH was 0.2 higher for litter than chemical fertilizer treatments, but this difference was not significant. Mehlich 1 P and WSP both increased throughout the two years, but no significant differences were found amongst split and single application or litter and inorganic fertilizers. Phosphorus balance analysis indicated that forage yield did not remove adequate P to prevent environmental concerns, when using N based applications. Fertilization increased yield 3.5 Mg ha-1 on average and yield responses to application timing and fertilizer types were similar. Desirable species abundance increased significantly (linear regression, P< 0.05) over time in both fertilizer and poultry litter application treatments. Furthermore at one site, Shenandoah County, poultry litter application actually reduced the number of weedy species in plots (P=0.04). Weedy plant abundance did not differ at either site, and no significant change in species richness (number of species/area) was observed at Rockbridge County for any treatment. No treatment effects were found for seed bank species richness and number of germinated seeds (m-2). No seedlings germinated directly from poultry litter collected from several sites in Virginia. Poultry litter was comparable to inorganic fertilizer in terms of increasing soil WSP, M1P, forage yield, and above ground composition of desirable forage species. Timing of application made no difference. Additionally, our results indicate that poultry litter has no viable seed and does not increase weed abundance in mixed naturalized pastures. / Master of Science