Using a high-resolution deep-towed seismic system, we have discovered a series of contour-current bedforms at the base of the Sigsbee Escarpment in the Bryant Canyon region of the northern Gulf of Mexico. We identify a continuum of bedforms that include furrows, meandering furrows, flutes and fully eroded seafloor. These contourcurrent bedforms are linked to current velocities ranging from 20 to upwards of 60 cm/s based on nearby current meter measurements and similar flume generated bedforms (Allen, 1969). We identify erosion and non-deposition of up to 25 meters of surface sediment at the base of Sigsbee Escarpment. Using 3-D and high-resolution seismic data, sediment samples, and submersible observations from the Green Knoll area, we further define contour-current bedforms along the Sigsbee Escarpment. The study area is divided into eleven zones based on bedform morphology, distribution, and formation processes. We identify a contourcurrent bedform continuum similar to that of the Bryant Canyon region, while the data reveals additional features that result from the interaction between topography and contour-currents. Three regional seismic marker horizons are identified, and we establish an age of ~19 kyr on the deepest horizon. The seismic horizons are correlated with very subtle changes in sediment properties, which in turn define the maximum depth of erosion for each of the individual bedforms. Finally, we show for the first time that furrowed horizons can be acoustically imaged in three dimensions below seafloor. Analysis of imagery of several horizons obtained from 3-D seismic data from the Green Knoll region establishes the existence of multiple paleo-furrow events. The contour current pattern preserved by the paleofurrows is similar to the presently active seafloor furrows. And, based on the morphology and development that we establish for the active seafloor furrows, we show that paleo-furrows are likely formed by currents that are in the same range as those measured today (20-60 cm/s), that erode into sediments with similar physical properties to the fine-grained hemipelagic sediments of the present-day seafloor. We further suggest the possibility that furrows are formed during inter-glacial highstands and buried during glacial lowstands.

The upper Colorado River drainage system yields approximately 104,000 acre-feet of silt annually to the Colorado River. In an attempt to reduce the silt load, federal land management agencies have installed numerous land surface treatments. A study was conducted to measure the economic benefits of the land treatments near Cisco, Utah, and to compare them to the treatment costs and to develop predictive criteria for estimating the optimum intensity of treatment. The economic evaluation was done in a benefit-cost framework and the criteria for estimating optimum intensity of treatment was done in a production-function framework. The land treatments were found to be effective in retaining silt, but treatment apparently resulted in decreased livestock carrying capacity. Over-all, the land treatments were found to be uneconomical.

Dysfunctional rangelands lose nutrients and material faster than they capture or create them. The objective of this study was to determine the effectiveness of contour furrows, drill seeding, and aeration treatments in capturing overland flow, concentrating resources, and establishing perennial bunch grasses to convert dysfunctional semiarid rangeland to a functional rangeland. The site, located on the Edwards Plateau in west Texas, USA, had bare, structurally crusted soils with sparse short-grasses (Scleropogon brevifolius). The site had a low infiltration rate contributing to excess overland flow and loss of nutrients, organic matter, and soil. Contour furrows were installed with varying intra-furrow distances (0.6 to 61 m) and then broadcast seeded to determine if furrow spacing would produce a vegetative response. Portions of the intra-furrow areas were aerated and drill seeded. All seed mixes contained warm season, perennial bunch grasses (Bouteloua curtipendula, Leptochloa dubia, and Setaria leucopila). Soil beneath furrows had greater soil water content (p-value < 0.05) than intra-furrow areas. Furrow plots had greater density of seeded grasses and total vegetation (19 individuals m-2 and 191 individuals m-2, respectively) than intra-furrow plots (0 individuals m-2 and 89 individuals m-2, respectively). This study supports other findings that suggest 1.5 m to 1.8 m is optimum intra-furrow spacing. Vegetative responses to drill seeding and aeration treatments were insignificant. Observations suggest that contour furrows are effective at establishment and support of perennial vegetation by capturing and retaining water that otherwise would be lost to runoff from untreated soil.

Dysfunctional rangelands lose nutrients and material faster than they capture or create them. The objective of this study was to determine the effectiveness of contour furrows, drill seeding, and aeration treatments in capturing overland flow, concentrating resources, and establishing perennial bunch grasses to convert dysfunctional semiarid rangeland to a functional rangeland. The site, located on the Edwards Plateau in west Texas, USA, had bare, structurally crusted soils with sparse short-grasses (Scleropogon brevifolius). The site had a low infiltration rate contributing to excess overland flow and loss of nutrients, organic matter, and soil. Contour furrows were installed with varying intra-furrow distances (0.6 to 61 m) and then broadcast seeded to determine if furrow spacing would produce a vegetative response. Portions of the intra-furrow areas were aerated and drill seeded. All seed mixes contained warm season, perennial bunch grasses (Bouteloua curtipendula, Leptochloa dubia, and Setaria leucopila). Soil beneath furrows had greater soil water content (p-value < 0.05) than intra-furrow areas. Furrow plots had greater density of seeded grasses and total vegetation (19 individuals m-2 and 191 individuals m-2, respectively) than intra-furrow plots (0 individuals m-2 and 89 individuals m-2, respectively). This study supports other findings that suggest 1.5 m to 1.8 m is optimum intra-furrow spacing. Vegetative responses to drill seeding and aeration treatments were insignificant. Observations suggest that contour furrows are effective at establishment and support of perennial vegetation by capturing and retaining water that otherwise would be lost to runoff from untreated soil.

No description available.

Many barriers can limit restoration success. In the first chapter of this thesis, the barrier of strong seed dormancy is addressed. While dormancy benefits the species' long-term survival, it can present a challenge within a restoration scenario where rapid establishment is required. Soaking seeds in gibberellic acid (GA3) can overcome dormancy. An easier and potentially more effective method to apply this hormone is to coat seeds with a GA3-impregnated polymer, which provides a slow release of the hormone. Seed dormancy can also be mitigated by creating a favorable microsite with increased soil moisture. We compared the emergence and establishment of penstemon seeds that were coated with GA3 to uncoated seeds planted in shallow drill rows versus deep, U-shaped furrows. These treatments were evaluated in fall and spring plantings at three field sites in the Great Basin Region of the United States. Overall, coating with GA3 improved the emergence and establishment of Palmer's penstemon (Penstemon palmeri; p < 0.01) and thickleaf penstemon (P. pachyphyllus; p < 0.001) but did not improve the emergence or establishment of firecracker penstemon (P. eatonii; p = 1). Between planting seasons, fewer seedlings emerged or established from spring than from fall planting (p < 0.001). Emergence and establishment were higher for all species in deep furrows than in shallow drill rows (p < 0.001). These results indicate that GA3 seed coating and deep, U-shaped furrows may improve the restoration success of some native forbs. Land managers could use these techniques to restore native forbs in dry, disturbed areas. The second chapter of this thesis addresses another barrier to successful restoration, specifically pathogenesis from soil and seed-borne fungus. Survival and growth of native seeds and seedlings can be limited by soil and seed-borne pathogens. Fungicides can combat fungal pathogens, but in some studies, fungicide treatments were ineffective at improving seedling emergence. These studies cite dry conditions leading to low fungal presence as the cause of the ineffectiveness of fungicide treatments for some years and sites. This study tested if fungicide treatment effectiveness is indeed related to the amount of fungus in the soil. We analyzed the emergence and biomass of uncoated, blank-coated, and fungicide-coated bluebunch wheatgrass (Pseudoroegneria spicata) across five soil fungal levels. For both percent emergence and total biomass, uncoated seed performed best in autoclaved soil and declined with increasing level of fungus, but the level of fungus did not impact fungicide-coated seed. When grown in autoclaved, untreated, or low fungal soils, percent emergence and total biomass from fungicide-coated seeds was not different from uncoated seeds. However, in medium and high fungal soils, the percent emergence and total biomass from fungicide-coated seeds were more than two times greater than uncoated seeds (p < 0.05). These results indicate fungicide seed coatings can be effective at increasing restoration success for bluebunch wheatgrass, but the effectiveness of this treatment depends on the microbial environment of the planting site.

Στόχος της παρούσας εργασίας είναι η συμβολή στη δημιουργία ενός γυρεολογικού άτλαντα για τα φυτά της Πανεπιστημιούπολης Πατρών. Γι’ αυτό το σκοπό, στη διάρκεια ενός χρόνου συλλέχθηκαν και αναγνωρίστηκαν 150 δείγματα από την Πανεπιστημιούπολη και δημιουργήθηκε ένα «Herbarium». Από κάθε είδος συλλέχθηκε ένας μεγάλος αριθμός ανθέων για επεξεργασία στο εργαστήριο. Στη διαδικασία αυτή ελήφθη το γυρεολογικό υλικό και ετοιμάστηκαν τα μικροσκοπικά παρασκευάσματα με τη μέθοδο ακετόλυσης Erdtman. Μελετήθηκαν οι εξής οικογένειες Apocynaceae (1), Boraginaceae (7), Buxaceae (1), Capparaceae (1), Caprifoliaceae (1), Caryophyllaceae (2), Compositae (15), Convolvulaceae (2), Cruciferae (2), Dipsacaceae (2) Euphorbiaceae (1), Geraniaceae (1), Gramineae (2), Iridaceae (2), Labiatae (9), Leguminosae (18), Liliaceae 6, Malvaceae (2), Oleaceae (3), Oxalidaceae (1), Papaveraceae (2), Plantaginaceae (1), Pinaceae (1), Pittosporaceae (1), Primulaceae (1), Ranunculaceae (4), Resedaceae (1), Scrophulariaceae (2), Solanaceae (1) Umbelliferae (3) Urticaceae (2), Verbenaceae (2). Μετά έγιναν για κάθε είδος τουλάχιστον 150 μετρήσεις των χαρακτηριστικών διαστάσεων των γυρεοκόκκων του που είναι η πολική (Ρ) και η ισημερινή (Ε) απόσταση και ο λόγος της πολικής προς την ισημερινή απόσταση (Ρ/Ε). Στη συνέχεια πραγματοποιήθηκε η στατιστική επεξεργασία των μετρήσεων και η εξαγωγή των μέσων τιμών και της διασποράς τους. Για κάθε είδος, περιγράφτηκαν τα μορφολογικά και ανατομικά χαρακτηριστικά στοιχεία των γυρεοκόκκων. Τέλος, η μορφολογική περιγραφή του γυρεοκόκκου ολοκληρώθηκε με τη φωτογράφηση στο Ο.Μ. των παρασκευασμάτων. Σε μερικά είδη παρατηρήθηκαν διαφορές ως προς τις βιβλιογραφικά δεδομένα από άλλες περιοχές, όσον αφορά το ανάγλυφο, την μορφολογία των ανοιγμάτων (Anemone pavonina) το μέγεθος των γυρεοκόκκων (Vicia villosa, Pimpinella peregrina, Onopordon illyricum κ. α.) Στο Onopordon illyricum L. βρήκαμε γυρεοκόκκους με Ρ = 59, 35 μm, Ε = 55,14 μm ενώ στη βιβλιογραφία αναφέρονται Ρ = 40 – 45 μm και Ε = 39 - 45 μm. Στο είδος Anemone pavonina Lam. η βιβλιογραφία αναφέρει πολυπορώδεις γυρεοκόκκους ενώ στο δικό μας υλικό οι γυρεόκοκκοι φαίνονται παντοκολπικοί. Στην Vicia villosa Roth.. βρήκαμε Ρ = 42,32 μm και Ε = 20,61 μm ενώ βιβλιογραφικά αναφέρονται τιμές Ρ = 28 – 35 μm και Ε = 14 – 21 μm. Αυτή η διαφοροποίηση είναι μια γεωγραφική διαφοροποίηση που σχετίζεται και συνοδεύεται και από μορφολογικές και γενετικές διαφορές. / The aim of the present study is the construction of a pollen atlas with regard to the plant species in the area of the University of Patras, Greece. For this purpose, 120 different samples were collected and characterized and a «Herbarium» was created. From each of the species, a big number of flowers were collected for further processing in the lab. Fresh polliniferous material was procured randomly from several plants growing in the field of the University of Patras. For light optical microscope (LO) studies pollen were acetolyzed following the protocol of Erdtman (1952). The plant taxa studied here belongs to the following families: Apocynaceae (1), Boraginaceae (7), Buxaceae (1), Capparaceae (1), Caprifoliaceae (1), Caryophyllaceae (2), Compositae (15), Convolvulaceae (2), Cruciferae (2), Dipsacaceae (2) Euphorbiaceae (1), Geraniaceae (1), Gramineae (2), Iridaceae (2), Labiatae (9), Leguminosae (18), Liliaceae 6, Malvaceae (2), Oleaceae (3), Oxalidaceae (1), Papaveraceae (2), Plantaginaceae (1), Pinaceae (1), Pittosporaceae (1), Primulaceae (1), Ranunculaceae (4), Resedaceae (1), Rubiaceae (1), Scrophulariaceae (2), Solanaceae (1) Umbelliferae (3) Urticaceae (2), Verbenaceae (2). At least 150 measurements were taken for each plant taxon pollen grain preparation, in order to calculate the mean value of the polar (Ρ) and equatorial (Ε) dimensions of the taxon’ s pollen grains, as well as, the ratio Ρ/Ε. Statistical analysis was performed and the mean values were recorded. The morphology and anatomy of each species pollen grains were determined. The study was completed by taking LM pictures of all pollen grains. In some of the species studied in the area we have noticed some differences between the pollen grains dimensions, or even the morphology of the pollen grain surface, and of the same taxa that are described from other countries (Anemone pavonina Lam., Onopordon illyricum L., Vicia villosa Roth., Pimpinella peregrina L.) In Onopordon illyricum L. we have found pollen grains with P = 59,35 μm, Ε = 55,14 μm and the same species from Spain is described with P = 40 – 45 μm ανδ Ε – 39 – 45 μm. Anemone pavonina Lam. is referred to have poliporate pollen grains, in our material it seems to have policolpate pollen grains. In Vicia villosa Roth. From Spain is referred P = 28 – 35 μm and E = 14 – 21 μm, and we found P = 42,32 μm and E = 20,61 μm. This might be a geographic differentiation that is normal in pollen grains and is related with other morphological and genetic differences.

Soil surface treatments consisting of gully plugs and contour furrows were constructed as a means of reducing erosion and holding sediment on site. To measure the effectiveness of the gully plugs and furrows, angle iron stakes and profile transects were installed to measure soils loss and accompanying change in the soil profile. The profile transects gave a reliable measure of the change in the height of the soil surface in constructed pits and across contour furrows. Because of the shrinking and swelling of the soil, the change in height of the angle iron stakes was found to be much more than the reduction in soil surface caused by erosion. High intensity thunderstorms, occuring mostly during July, August, and September, cause most of the erosion from the semi-arid land. The gully plugs and contour furrows were effective in holding runoff and sediment on site, but the life expectancy of the treatments is only about fifteen years.

The consequence of the differentiation of a care of forest ecosystems in NP Šumava is the existence of localities where timber harvesting causes damage to forest ecosystem. One of the most affected ecosystems is the soil ecosystem. The surface is usually disrupted by numbers of passing over the same path the machines. Forwarders are the harvesting machineries that execute the largest number of passes in the forest. The aim of the diploma work is to gain and analyse data dealing with harvesting technologies, and to evaluate their impact on soil ecosystems. The impact was determinate from measuring of the recessing of the track in the surface, of the soil compaction and of the soil sampling for determination of an amount of the water in the soil. The data were measured in different selected localities in NP Šumava. The negative influences of the harvesting technologies were defined for both {--} water and air regime of soil. Recommendation for reduction of negative consequences of the harvesting on soil are parts of diploma work as well.

<p>This dissertation explains why behavioral genetic research can be better informed by using characteristics in the human iris as biomarkers for personality, and is divided into five parts. Part I gives an introduction to the classical twin method and an overview of the findings that have led most developmental researchers to recognize that the normal variation of personality depends on a complex interplay between genetic and environmental factors. Part II highlights empirical findings that during the last twenty years have gradually moved genetic and environmental theory and research to evolve toward one another, and also presents the theory of genetics and experience that currently is used to explain how the interplay between genes and the environment works. Part III explains why, from a developmental perspective, it is of interest to identify candidate genes for personality, and gives a brief overview of genes that have been associated with personality. Problems associated with genetic research on the molecular level and how these apply to personality are also highlighted. Part IV examines molecular research on the iris and the brain, which suggests that genes expressed in the iris could be associated with personality, and explains how the use of iris characteristics can increase power to test candidate genes for personality by taking advantage of the self-organizing properties of the nervous system. The empirical foundation for the questions posed in this dissertation and also the empirical results are presented here. Part V discusses the associations found between iris characteristics and personality, and exemplifies how iris characteristics can be used within the theoretical frameworks presented in parts I, II, III and IV. In other words, Part V explains how iris characteristics – in addition to identify as well as test candidate genes for personality – can be used to investigate how people’s experiences in themselves are influenced by genetic factors.</p>