Plumage damage (PD) as a result of severe feather pecking (SFP) and skin lesions (SL) due to cannibalism (CA) is serious welfare, performance, and economic problems in commercial layer farms. Genetics, nutrition, and housing conditions are central complexes that contribute to the multifactorial causes of these behavioral disorders. Practical recommendations consider the quality of litter as an important criterion for the prevention of SFP, although systematic longitudinal studies providing evidence-based findings are lacking. Therefore, the aim of this study was to investigate the effects of litter condition on the occurrence of PD and SL in the field using a longitudinal design. Integument scoring (PD and SL; 7 times), litter scoring (structure, cake formation, litter quality, and litter height; 12 times), and laboratory litter analysis (dry matter (DM), nitrogen (N), phosphorus (P) and pH value; 12 times) were performed in 28 laying hen flocks with a median flock size of 12,357 birds, in barn (n = 21) or free-range systems (n = 7), during the first laying period. Binary logistic regression (BLR) models showed the association of housing type and animal age on PD and SL (P < 0.001), and of the hybrid type on PD (P < 0.001). Furthermore, a significant association with PD and SL was observed for several litter traits. An increase in litter height, DM, and P was associated with lower PD (P ≤ 0.022) and SL (P < 0.001). In contrast, a higher N content of the litter was associated with an increase in SL (P = 0.007). Cake formation (P < 0.001) and a low structure (P = 0.025) of the litter showed an association with higher PD. In conclusion, this study identified caked litter with less structure, low height, and low contents of DM and P as risk factors for behavioral disorders in commercial laying flocks.

<p> The net ecosystem CO2 exchange and Sphagnum net primary production of an abandoned block-cut bog were measured in the field and in the laboratory using gas exchange techniques. Environmental variables were measured concurrently. Seasonal Sphagnum growth and decomposition were determined using crank wires and litter bags.</p> <p> The bog was a net source of CO2 during the summer months. While, Sphagnum did grow over the study period, the Sphagnum net primary production was offset by peat respiration. Sphagnum net primary production and net ecosystem CO2 exchange at the abandoned block-cut bog are within the ranges found for natural peatlands.</p> <p> Sphagnum photosynthesis was greatest at wet sites and at the start and end of the study period when the water table was higher and the temperature was cooler. Ericaceous shrub cover strongly affected Sphagnum growth. Sites with vascular plant cover photosynthesized at approximately twice the rate of sites where cover was removed.</p> <p> Laboratory results indicate that drying and wetting cycles negatively affect Sphagnum net primary production and net ecosystem CO2 exchange. Sphagnum and peat respiration increased 4 to 14 fold upon rewetting whereas Sphagnum photosynthesis did not recover until 20 days of saturation.</p> <p> The results emphasize the importance of stable moisture availability for the development of a new acrotelm. The peatland will likely remain a source of CO2 until the acrotelm is able to counterbalance the peat respiration.</p> / Thesis / Master of Science (MSc)

Autotrophs and heterotrophs differ in their demand, acquisition and use of materials, but fundamentally nutrient demand is inherently linked to metabolism based on the stoichiometry of biochemical reactions. The differences between these two groups of organisms confound straightforward regression approaches to quantifying the relationship between nutrient demand and metabolism at an ecosystem level. We address how nutrient demand in headwater streams changes with shifts in organic matter supply and associated microbial activity by investigating these relationships in the predominantly heterotrophic conditions of a southern Appalachian stream. We measured litter input, organic matter standing crops, litter respiration rates and nitrate demand several times during the course of decomposition. There was a strong relationship between leaf standing crop and nitrate uptake efficiency across dates with maximal efficiency occurring when litter standing crops were highest. There was also an increase in nitrogen (N) uptake rate relative to respiration rates as breakdown progressed, which appears to be due to a shift in nutrient supply from the substrate to the water column associated with the depletion of labile, high quality organic matter in the substrate. It is our contention that streams establish a gradient of resource supply from particulate to dissolved sources that coincides with the movement of materials from terrestrial to marine systems. / Master of Science

Water stress is the most critical environmental factor limiting crop production in the US Piedmont. The presence of humic substances in composted organic amendments may increase crop tolerance to water stress through their hormone-like effects on plant metabolism. The objectives of this study were to calculate N mineralization rates of composted and non-composted organic materials used in this long-term field study, and to determine differences in soil physiochemical properties, corn and soybean leaf physical and biochemical properties yield and seed quality between organically amended and inorganically fertilized treatments. Nitrogen mineralization rates were greatest in the poultry litter (21%) and Panorama yard waste compost (4.5%) amended plots. Nitrogen uptake (120 mg/pot, 133 mg/pot, respectively) in these treatments were greater than that in the control (0N) (91.3 mg/pot) treatment. Wolf Creek biosolids compost and Huck's Hen Blend yard waste compost induced N immobilization (-5.0% and 0.18%, respectively), and had N uptake values similar to the control (92.6 mg/pot and 95.7 mg/pot). Rivanna biosolids compost immobilized N (-14.8%) but N uptake (136 mg/pot) was greater than that in the control due to the relatively high inorganic N content in the amendment. The total N concentration and C:N values were less reliable variables in predicting N mineralization when a significant portion of the total N was in the inorganic form. The annual application of poultry litter, Rivanna biosolids compost, and Panorama yard waste compost at 100% agronomic nitrogen and 30 % agronomic nitrogen rates in the field study improved soil fertility and increased total organic and humified carbon contents relative to the inorganically fertilized and control treatments. The amended treatments had slightly greater plant available water contents (average 10.0 cm/15 cm) than the control (8.38 cm/15 cm). Leaf water potential measurements revealed that neither crop experienced water stress during the sampling season. Treatment differences in leaf antioxidant activity were only observed in corn. All corn plants that were fertilized with amendments supplying the crop's nitrogen needs, regardless of the source, had greater leaf nitrogen (+29%), chlorophyll (+33%), and protein contents (+37%), lower superoxide dismutase (-29%) and ascorbate peroxidase (-17%) activities, and lower malondialdehyde (-33%) contents relative to the control and low nitrogen treatments. There were no observed differences in catalase activity, which was likely due to the evolutionary advantage of C4 metabolism. Yield was strongly related to midseason leaf nitrogen contents (R2=0.87, p<0.0001) and not soil humified carbon (R2=0.02, p=0.0543). There were no observed treatment differences in soybean leaf physiology and metabolism. Differences, however, were observed over time. As the leaves senesced, leaf chlorophyll, protein, superoxide dismutase and catalase activities decreased, and the malondialdehyde content increased. Ascorbate peroxidase activity slightly increased with time. Catalase activity in soybean was primarily driven by the oxidation of glycolate, a product of photorespiration, and not the formation of reactive oxygen species in the chloroplasts. The organically amended treatments had higher yields (9-21% increase), greater protein contents (4-9% increase), and seed weights (5-14% increase) relative to the fertilizer and control treatments. It was concluded that differences in soybean yield and seed quality were due to non-nutritive benefits of the organic amendments and not available water or plant nutrition. / Master of Science

El objetivo de esta tesis ha sido estudiar la respuesta directa a la selección por tasa de ovulación en conejo y las respuestas correlacionadas en tamaño de camada y tasas de supervivencia. Los animales pertenecían a una línea de conejos seleccionada por tasa de ovulación durante 10 generaciones. La selección se realizó en base al valor fenotípico de la hembra, que se midió el día 12 de la segunda gestación mediante laparoscopia. Se creó una línea control a partir de la recuperación de aproximadamente 470 embriones de 50 hembras donantes de la generación base. Los embriones fueron vitrificados y almacenados en nitrógeno líquido hasta su transferencia al final del experimento de selección (generación 10 de la línea seleccionada). Se midieron los siguientes caracteres: tamaño de camada (LS), estimada como el número total de gazapos al parto en un máximo de 5 partos; tasa de ovulación (OR), estimada como el número de cuerpos lúteos en los dos ovarios; tasa de ovulación derecha y tasa de ovulación izquierda (ROR y LOR); el número de embriones implantados totales (IE), en el lado derecho (RIE) y en el lado izquierdo (LIE); la diferencia ovulatoria (OD), definida como la diferencia entre ROR y LOR, expresada en valor absoluto; la diferencia de implantación (ID), definida como la diferencia entre RIE y LIE, expresada en valor absoluto; la supervivencia embrionaria (ES), calculada como IE/OR; la supervivencia fetal (FS), calculada como LS/IE; la supervivencia prenatal (PS), calculada como LS/OR. Se utilizó metodología bayesiana para analizar los datos. Las estimas de las heredabilidades de OR, LS, ES, FS y PS fueron 0.16, 0.09, 0.09, 0.24 y 0.14, respectivamente. Las estimas de las correlaciones fenotípicas de OR con LS, ES, FS y PS fueron 0.09, -0.07, -0.26 and -0.28, respectivamente. Las estimas de las correlaciones genéticas de OR con LS y ES tuvieron una baja precisión, y no se pudo concretar su signo. Las estimas de las correlaciones genéticas de OR con FS y PS fueron negativas (probabilidad de ser negativa de 1.00 y 0.98, respectivamente). Las correlaciones fenotípicas y genéticas entre LS y las tasas de supervivencias fueron positivas (probabilidad de ser positivas de 1.00). / Laborda Vidal, P. (2011). Selection for ovulation rate in rabbits [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/14121

Selection strategies to increase productive traits of farm animals have been effective and highly specialized breeds and strains were obtained. At the same time, the effort made to obtain extremely high producing animals was accompanied by undesired effects, such as a reduced ability to sustain production, reproduction and health; especially under constrained conditions. The perception that selection was degrading robustness, lead to selection strategies aiming to improve the ability of animals to perform in a wider range of environmental constrain. However, at the present moment, the physiological mechanisms allowing farm animals to perform well in a wide range of environments, while others succumb, have not been described. The present thesis intended to address this question by describing the evolution of traits related to fitness, survival and to the adaptability to environmental constraints. Two maternal rabbit lines differing in their ability to face the environmental constraints, i.e. a `specialist¿ and a `generalist¿ maternal rabbit line were available. Additionally, two generations (20 generations apart) of the specialized line were simultaneously available. During the first two consecutive reproductive cycles, female rabbits were simultaneously subjected to three environmental conditions differing in the intensity and in the physiological constrain imposed. Digestive capacity, the acquisition of resources and the partitioning of resources into different function (i.e. litter size, milk yield, growth, body reserves, etc.) was also assessed. Results showed a greater acquisition capacity of `generalist¿ females in constrained conditions with respect to `specialist¿ females. Moreover, the greater acquisition capacity was not accompanied by a reduction in the digestive efficiency, allowing the `generalist¿ females a relative greater acquisition of digestible energy. The maintenance of reproductive performance by having a greater acquisition capacity, together with the avoidance of making an intensive use of body reserves were both related to the capacity of `generalist¿ females to sustain reproduction in a wide range of environmental conditions. Twenty generations of selection exclusively for reproduction (specialized line), was not accompanied by a higher acquisition capacity, but by a change in the relative priority between the litter being nursed (actual) and the litter being gestate (future litter). In this sense, females from the actual generation of selection for litter size at weaning had a greater milk yield in the first week of lactation (period of great importance to kits survival), reducing it by the end of lactation. The present thesis also evidenced the importance of the environment where the animals are being selected in the evolution of the interplay between competing functions. / Savietto, D. (2014). Environmental and genetic factors driving robustness in reproductive rabbit does [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/37198 / Premios Extraordinarios de tesis doctorales

Tesis por compendio / [ES] La selección divergente puede cambiar las frecuencias de los marcadores genéticos en direcciones opuestas, produciéndose frecuencias alélicas intermedias en estos marcadores cuando ambas líneas divergentes son consideradas conjuntamente en los análisis genéticos. Por lo tanto, los experimentos de selección divergente aumentan el poder de detección para estudios de asociación de genoma completo (GWAS) y para estudios de escaneo genómico por medio de métodos de huellas de selección. GWASs bayesianos, utilizando el modelo Bayes B, se implementaron para analizar datos genómicos de los caracteres de tamaño de camada del experimento de capacidad uterina con 181 hembras. Las asociaciones fueron evaluadas calculando los factores de Bayes para cada SNP, y calculando los porcentajes de la varianza genómica para cada ventana no solapada de 1-Mb. Los GWASs descubrieron SNPs asociados con el número total de gazapos al parto y los embriones implantados. Además, se revelaron regiones genómicas relevantes para el número total de gazapos al parto (1 región), el número de nacidos vivos (1 región), los embriones implantados (3 regiones) y la tasa de ovulación (5 regiones). Los porcentajes de varianza genómica que explicaban los anteriores caracteres de tamaño de camada fueron 39,48%, 10,36%, 37,21% y 3,95%, respectivamente, en un modelo que excluye el efecto línea; y 7.36%, 1.27%, 15.87% y 3.95%, respectivamente, en un modelo con el efecto línea. La región genómica localizada en el cromosoma del conejo (OCU) 17 en 70.0 - 73.3 Mb se consideró como un nuevo locus de carácter cuantitativo (QTL) asociado a caracteres reproductivos en conejos, ya que esta región fue encontrada solapada para el número total de gazapos al parto, el número de nacidos vivos y los embriones implantados. El gen de la proteína morfogenética ósea 4, BMP4, es el principal gen candidato prometedor dentro del nuevo QTL. Una combinación de GWASs fueron implementados para analizar los datos genómicos del experimento de la grasa intramuscular con 480 conejos. Los métodos de GWASs incluyeron un método bayesiano, modelo Bayes B; y un método frecuentista, regresiones de marcadores únicos con los datos ajustados por el parentesco genómico. Este estudio reveló cuatro regiones genómicas relevantes en OCU1 (1 región), OCU8 (2 regiones) y OCU13 (1 región) asociadas con la grasa intramuscular. La región asociada más importante estaba en OCU8 en 24.59 - 26.95 Mb, y explicó el 7.34% de la varianza genómica. El bajo porcentaje explicado por las principales regiones genómicas relevantes indica un gran componente poligénico para la grasa intramuscular. Los análisis funcionales recuperaron genes vinculados con las rutas y funciones de los metabolismos de energía, carbohidratos y lípidos. Además, se realizó un estudio de escaneo genómico usando conejos del experimento de selección divergente para grasa intramuscular, y usando tres métodos de firmas de selección: índice de fijación de Wright (Fst), coeficiente de verosimilitud compuesto entre poblaciones (XP-CLR) y extensión de homocigosidad de los haplotipos entre poblaciones (XP-EHH). Los resultados mostraron múltiples huellas de selección en todo el genoma del conejo. Ninguna de estas huellas de selección concuerda con las regiones genómicas asociadas con la grasa intramuscular, provenientes de los resultados de los GWASs. En síntesis, los resultados de ambos experimentos, GWASs y el estudio de escaneo genómico, sugieren que la arquitectura genómica de la grasa intramuscular en el conejo parece ser altamente poligénica y sus variantes causales serían apenas detectables. Este estudio demuestra que la detección de variantes causales y marcadores genéticos asociados depende de las hipotéticas arquitecturas genómicas de los caracteres, independientemente de las exitosas respuestas logradas en los dos experimentos de selección divergente. Hasta la fecha, estos hallaz / [CA] La selecció divergent pot alterar les freqüències dels marcadors genètics en direccions oposades, donant lloc a freqüències al·lèliques intermèdies quan les dos línies divergents es consideren conjuntament en els anàlisis genètics. Per tant, els experiments de selecció divergents augmenten el poder de detecció en estudis d'associació de genoma ampli (GWAS) i en estudis d'exploració genòmica a través de mètodes de signatures de selecció. GWASs bayesians, utilitzant el model Bayes B, es van implementar per a analitzar dades genòmiques de caràcters de grandària de ventrada de l'experiment de capacitat uterina amb 181 conilles femelles. Les associacions es van provar calculant els factors de Bayes per a cada SNP, i calculant els percentatges de la variància genòmica per a cada finestra no superposada d'1-Mb. Els GWASs van descobrir SNPs associats amb el número total de llorigons al part i els embrions implantats. A més, es van revelar regions genòmiques rellevants per al número total de llorigons al part (1 regió), el número de nascuts vius (1 regió), els embrions implantats (3 regions) i la taxa d'ovulació (5 regions). Els percentatges de variància genòmica que explicaven els anteriors caràcters de grandària de ventrada van ser 39,48%, 10,36%, 37,21% i 3,95%, respectivament, sota un model que exclou l'efecte de línia; i 7.36%, 1.27%, 15.87% i 3.95%, respectivament, sota un model amb efecte de línia. La regió genòmica situada en el cromosoma del conill (OCU) 17 en 70.0 - 73.3 Mb es va considerar com un nou locus de caràcters quantitatius (QTL) associat a caràcters reproductius en conills, ja que aquesta regió es va superposar per al número total de llorigons al part, el número de nascuts vius i els embrions implantats. El gen de la proteïna morfogenètica òssia 4, BMP4, és el principal gen candidat prometedor dins del nou QTL. Una combinació de GWASs es van implementar per a analitzar les dades genòmiques de l'experiment del greix intramuscular amb 480 conills. Els mètodes GWASs van incloure un mètode bayesià, model Bayes B; i un mètode frecuentista, regressions de marcadors únics amb les dades ajustades pel parentiu genòmico. Aquest estudi va revelar quatre regions genòmiques rellevants en OCU1 (1 regió), OCU8 (2 regions) i OCU13 (1 regió) associades amb el greix intramuscular. La regió associada més important estava en OCU8 en 24.59 - 26.95 Mb, i va explicar el 7.34% de la variància genòmica. El baix percentatge explicat per les principals regions genòmiques rellevants indica un gran component poligènic per al greix intramuscular. Els anàlisis funcionals van recuperar gens relacionats amb les rutes i la funció d'energia, metabolismes de carbohidrats i lípids. A més, es va realitzar un estudi d'exploració del genoma usant conills de l'experiment de selecció divergent per a greix intramuscular, i usant tres mètodes de signatures de selecció: índex de fixació de Wright (Fst), coeficient de versemblança compost entre poblacions (XP-CLR) i extensió de homocigosidad dels haplotipos entre poblacions (XP-EHH). Els resultats van mostrar múltiples petjades de selecció en tot el genoma del conill. Cap d'aquestes petjades de selecció concorda amb les regions genòmiques associades a partir dels resultats dels GWASs. En síntesi, els resultats dels dos experiments, GWASs i estudi d'exploració del genoma, suggereixen que l'arquitectura genòmica del greix intramuscular en el conill sembla ser altament poligènica i les seues variants causals serien a penes detectables. Aquest estudi demostra que la detecció de variants causals i marcadors genètics associats depèn de les hipotètiques arquitectures genòmiques dels caràcters, independentment de les respostes reeixides en els dos experiments de selecció divergents. Fins ara, aquestes troballes no tindrien implicacions valuoses per als programes de cria de conills. / [EN] Divergent selection can alter frequencies of genetic markers in opposite directions, leading to intermediate allelic frequencies when both divergent lines are jointly considered in the genetic analyses. Therefore, divergent selection experiments increase the detection power for genome wide association studies (GWAS) and for genomic scan studies through methods of selection signatures. Bayesian GWASs using Bayes B model was used to analyse genomic data of litter size traits of the uterine capacity experiment with 181 does. The associations were tested by computing Bayes factors for each SNP, and by computing percentages of the genomic variance for each 1-Mb non-overlapping window. The GWASs uncovered SNPs associated with total number born and implanted embryos. Moreover, relevant genomic regions were revealed for total number born (1 region), number born alive (1 region), implanted embryos (3 regions), and ovulation rate (5 regions). The percentages of genomic variance that accounted for these litter size traits were 39,48%, 10.36%, 37.21%, and 3.95%, respectively, under a model excluding line effect; and 7.36%, 1.27%, 15.87%, and 3.95%, respectively, under a model with line effect. The genomic region located on the rabbit chromosome (OCU) 17 in 70.0 - 73.3 Mb was deemed as a novel quantitative trait locus (QTL) of reproductive traits in rabbits, since this region was found overlapped for total number born, number born alive and implanted embryos. Bone morphogenetic protein 4 gene, BMP4, is the main promising candidate gene within the novel QTL. A combination of GWASs were performed for analysing the genomic data of the intramuscular fat experiment with 480 rabbits. The GWAS methods included a Bayesian method, Bayes B model; and a frequentist method, single marker regressions with the data adjusted by genomic relatedness. This study revealed four relevant genomic regions in OCU1 (1 region), OCU8 (2 regions) and OCU13 (1 region) associated with intramuscular fat. The most important associated region was on OCU8 in 24.59 - 26.95 Mb, and accounted for 7.34% of the genomic variance. The low percentage explained by the main relevant genomic regions indicates a large polygenic component for intramuscular fat. Functional analyses retrieved genes linked to pathways and function of energy, carbohydrate and lipid metabolisms. In addition, a genome scan study was performed using rabbits from the divergent selection experiment for intramuscular fat, and using three methods of selection signatures: Wright's fixation index (Fst), cross population composite likelihood ratio (XP-CLR) and cross population extended haplotype homozygosity (XP-EHH). The results showed multiple selection signatures across the rabbit genome. None of these selection signatures agreed with the associated genomic regions from GWAS findings. In synthesis, the results of both experiments, GWAS and genome scan study, suggest that the genomic architecture of intramuscular fat in rabbit seems to be highly polygenic and their causative variants would be hardly detectable. This study demonstrates that detection of causative variants and associated genetic markers depends on the hypothetical genomic architectures of traits, regardless of the successful responses attained in the two divergent selection experiments. Hitherto, these findings would not have worthwhile implications for the rabbit breeding programs. / Sosa Madrid, BS. (2020). Genomic analysis of divergently selected experimental lines in rabbit [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/141376 / Compendio

Hormones are endocrine disrupting compounds, which have been shown to alter the sexual development of aquatic organisms. Animal manure applications to agricultural fields for nutrient management can be a source of environmental hormones. This dissertation investigates the occurrence of hormones in fields applied with various manures and their adjacent streams, as well as the effect of manure application technologies on the fate of hormones in soils, sediments, and runoff. A total of 11 hormone compounds were studied. All studied analytes were quantified using liquid chromatography and triple-quadrupole mass spectrometry following various sample extraction and clean-up strategies. The spatial and temporal distribution of manure-associated hormones in a manure surface applied agricultural field and adjacent stream was studied at time points up to 7.5 months after a routine manure application. Hormones were detected mainly in the top 0-5cm soils. Significantly higher levels of hormones were found in the drystack applied area of the field when compared to dairy manure slurry applied portion. New technologies for the subsurface application of poultry litter show promise as a tool to reduce the transportation of environmental hormones in surface runoff. Once adequate sampling protocols were established; it was determined that subsurface injection of both dairy manure and poultry litter reduced the impact of manure surface runoff. Hormones also showed little vertical and lateral movement in the soil. The transformation rates of 1,4-androstadiene-3,17-dione, 4-androstene-3,17-dione and estrone were studied comparing the effects of temperature, soil type, and application type. The calculated half-life of 1,4-androstadiene-3,17-dione in poultry litter surface-applied soils was 1.9 times higher than that in the poultry litter subsurface-injected soils, indicating a faster dissipation rate in the injection slits. Estrone persisted at detectable levels for the duration of the study in all treatments. The continued use of best management practices and innovative manure management techniques for the reduction of nutrients, sediment and other contaminants has the potential to also reduce hormone transport to the natural environment. Monitoring many different types of hormones in all areas of an environmental system will continue to provide better information on the occurrence and fate of hormones sourced from manure amended soils. / Ph. D. / Hormones can contaminate streams and cause harm in the environment by interfering with the sexual development of aquatic organisms. Hormones are naturally occurring in animal manure, which is applied to agricultural fields for nutrients. Animal manures are usually spread on the surface of the soil and hormones can travel from the field to the streams when it rains. There are new technologies where the manure is injected into the soil instead of spread on the surface that could reduce the environmental impact of hormones in manure. This dissertation investigated the how hormones behave in fields applied with animal manures using the surface application technique and the subsurface injection technique. We investigated how long hormones persist in the soil, and their levels in manures, runoff from precipitation, and in waterways. Hormones were shown to stay in the top 0-5cm of soil, and to remain in the manure injection slit, showing that they do not easily move in the environment. Hormones were only detected in runoff water from soils that had surface applied manures. The transformation rate of hormones that were found at the highest levels in all the manures analyzed in this research was studied. It was determined that manure subsurface injection caused one of the compounds to transform at a faster rate in the soil. Overall, hormones were detected for up to 9 weeks in soils that were applied with animal manures. Best management practices such as manure subsurface injection and using a buffer zone between an agricultural field and a stream are promising tools for preventing hormones in animal manure from entering the natural environment.

The Virginia Division of Litter Control's education package entitled Operation Waste Watch (OWW) was evaluated at the first, fourth, and sixth grade level in 19 elementary schools in two southwestern counties in Virginia. Evaluation was provided for the standard curriculum program and for a specially modified behavioral version of the original material. Program evaluation for both curriculum packages was provided immediately before, after, and three months after the implementation of the program and consisted of student achievement testing in terms of knowledge about solid waste management and the assessment of actual student behavior. Specifically, the data was analyzed according to the factorial design: 3 Grade (First, Fourth, Sixth) x 3 Curriculum Condition (Standard, Modified, Control) x 3 Phase (Pre, Post, Follow-up). Significant improvements following the implementation of the educational curriculum occurred only for the student achievement tests. Both programs were found to significantly raise student test performance immediately following presentation of the curriculum materials. The level of student knowledge three months later was also found to statistically surpass baseline performance. However, there was little or no evidence, during Posttesting or Followup, of superior performance by students receiving the modified curriculum program. Supplemental information from the teachers concerning the overall effectiveness of the different curriculum components indicated that while the materials of OWW were needed and generally well constructed, there were severe problems concerning the amount of time needed to adequately teach the different student activities. / Ph. D.

Climate change resulting from emissions of fossil fuel combustion has sparked considerable interest in renewable energy and fuel production research, particularly energy derived from cellulosic ethanol, which is derived from biomass such as wood and grass. Cellulosic ethanol demonstrates a more promising future as a global energy source than corn-derived ethanol because it does not displace food crops, irrigation is not required, and chemical application rates are much lower than for annual crops, such as corn. Growing cellulosic biomass for energy can help reduce greenhouse gas emissions via carbon (C) sequestration and by reducing demand for fossil fuel production. The objective of this study was to investigate how land use change affects soil properties and selected soil C and nitrogen (N) dynamics among alternative cellulosic biofuel treatments at the Weyerhaeuser Alabama Cellulosic Biofuel Research site in west-central Alabama. Composite soils for characterization, along with forest floor, were collected at year 1 and year 2 after treatment establishment at 0-15cm and 15-30cm depths at six locations along three hillslope-riparian transects in five experimental watershed treatments. Decomposition of loblolly pine needles was assessed in each watershed using an in situ litter bag method. Seasonal in situ net nitrogen mineralization was measured using a sequential core method, and an anaerobic incubation for N mineralization potential of composite soils was performed in the laboratory. Results revealed high variability of soil properties and processes within these watersheds, along with no consistent treatment effects. This study provides baseline data for these watershed treatments for future studies. / Master of Science