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31	EFFECTS OF IMPERVIOUS SURFACES ON OVERWINTERING SURVIVAL OF EVERGREEN BAGWORM AND ABUNDANCE OF SCALE INSECT PESTS IN THE URBAN ENVIRONMENT Sujan Dawadi (12218648) 18 April 2022 (has links) <p>Urban areas are warmer than surrounding rural areas. During the cold of winter, warming increases surrounding host temperature and may improve the overwintering survival of marginally hardy insects like evergreen bagworms. Similarly, during the summer, it has the potential to increase the fecundity and abundance of sap feeding insect pests such as scale insects in ways that change the capacity of their natural enemies to regulate their populations. </p> <p>Although in parts of Indiana winters can be cold enough to kill bagworm eggs, they thrive in cities. I conducted field experiments to determine the extent to which impervious surface near an infestation could keep temperatures warm enough to affect bagworm survival during cold of winter. My results suggest that the percentage of live eggs inside overwintering pupae decreased as ambient temperature drops. This response was moderated by the presence of impervious surface around an infested plant. Eggs found in bagworms collected from host trees surrounded by more impervious surface had a higher chance of survival than those collected from trees with low levels of hardscape. However, impervious surface has its limit such that egg mortality was not buffered by impervious surfaces at temperatures at or below -21.67°C. Similarly, I also conducted field experiments with sap feeding insects on honeylocust trees, a commonly planted tree in cities. Hot sites had a mean daily temperature more than 1.5 °C warmer than cool sites and scale insects were more abundant and fecund on trees in the hottest part of Indianapolis compared to cooler areas. No differences were observed in rates of parasitism on the scale insect. However, I found strong density dependence relation between parasitoids and scales abundance at scale density at or below the levels present in cool sites. The top-down regulation was prevalent at or below a critical density of scale hosts. Conversely, bottom-up regulation was prevalent above this host density as pests benefit from bottom-up factors. This suggests that urban habitats helped the scales to escape biological control by resident natural enemies above critical density of scale hosts. </p> <p>My findings can be useful to landscape designers to design landscapes that are less prone to insect pests. My finding adds to a growing body of evidence that suggests that planting urban trees with lesser amount of impervious surface can help reducing the urban warming effect and increase the regulation from natural enemies. </p> Ecology Climate Change Processes Landscape Ecology Forestry Pests, Health and Diseases overwintering survival impervious surface area evergreen bagworm impervious surface threshold European fruit lecanium scale honeylocust scurfy scale top-down regulation density-dependent Urban habitats
32	自己間引き個体群における密度効果のロジスチック理論萩原, 秋男, HAGIHARA, Akio 12 1900 (has links) (PDF) 農林水産研究情報センターで作成したPDFファイルを使用している。 the law of constant final yield 密度依存的な枯死密度効果一般ロジスチック曲線逆数式自己間引き個体群最終収量一定の法則 density-dependent mortality density effect general logistic equation reciprocal equation self-thinning population
33	自己間引き個体群における平均個体重 - 密度の軌跡に関する理論的研究萩原, 秋男, HAGIHARA, Akio 12 1900 (has links) (PDF) 農林水産研究情報センターで作成したPDFファイルを使用している。ロジスチック理論平均個体重 - 密度の軌跡自己間引きの3/2乗則 density-dependent mortality density effect logistic theory mean plant weight-density trajectory the 3/2 power law of self-thinning 密度効果密度依存的な枯死 C-D効果の一般逆数式
34	Variable-Density Flow Processes in Porous Media On Small, Medium and Regional Scales Walther, Marc 03 November 2014 (has links) (PDF) Nowadays society strongly depends on its available resources and the long term stability of the surrounding ecosystem. Numerical modelling has become a general standard for evaluating past, current or future system states for a large number of applications supporting decision makers in proper management. In order to ensure the correct representation of the investigated processes and results of a simulation, verification examples (benchmarks), that are based on observation data or analytical solutions, are utilized to evaluate the numerical modelling tool. In many parts of the world, groundwater is an important resource for freshwater. While it is not only limited in quantity, subsurface water bodies are often in danger of contamination from various natural or anthropogenic sources. Especially in arid regions, marine saltwater intrusion poses a major threat to groundwater aquifers which mostly are the exclusive source of freshwater in these dry climates. In contrast to common numerical groundwater modelling, density-driven flow and mass transport have to be considered as vital processes in the system and in scenario simulations for fresh-saltwater interactions. In the beginning of this thesis, the capabilities of the modelling tool OpenGeoSys are verified with selected benchmarks to represent the relevant non-linear process coupling. Afterwards, variable-density application and process studies on different scales are presented. Application studies comprehend regional groundwater modelling of a coastal aquifer system extensively used for agricultural irrigation, as well as hydro-geological model development and parametrization. In two process studies, firstly, a novel method to model gelation of a solute in porous media is developed and verified on small scale laboratory observation data, and secondly, investigations of thermohaline double-diffusive Rayleigh regimes on medium scale are carried out. With the growing world population and, thus, increasing pressure on non-renewable resources, intelligent management strategies intensify demand for potent simulation tools and development of novel methods. In that way, this thesis highlights not only OpenGeoSys’ potential of density-dependent process modelling, but the comprehensive importance of variable-density flow and transport processes connecting, both, avant-garde scientific research, and real-world application challenges. Dichteabhängig Strömung Stofftransport Wärmetransport Grundwasser Numerische Simulation Finite-Elemente-Verfahren FEM OpenGeoSys OGS Open Source Benchmark IWAS Oman Al-Batinah Arid Fallstudie Viskosität Gel Dichte thermohaline Stabilität Variable-Density Density-Driven Density-Dependent Flow Mass Transport Heat Transport Numerical Simulation Finite-Element-Method FEM OpenGeoSys OGS Open Source Benchmark IWAS Oman Al-Batinah Case Study Arid Viscosity Gel Density Thermohaline Stability ddc:550 rvk:AR 22140 rvk:AR 22600 Grundwasser Finite-Elemente-Methode Viskosität Temperatur Transportprozess Simulation Dichte <Physik> Fallstudie Salzwasser-Süßwasser-Grenze Salzwasser Meerwasser Oman Open Source Benchmark Semiarides Gebiet Gel Stabilität
35	Variable-Density Flow Processes in Porous Media On Small, Medium and Regional Scales Walther, Marc 07 May 2014 (has links) Nowadays society strongly depends on its available resources and the long term stability of the surrounding ecosystem. Numerical modelling has become a general standard for evaluating past, current or future system states for a large number of applications supporting decision makers in proper management. In order to ensure the correct representation of the investigated processes and results of a simulation, verification examples (benchmarks), that are based on observation data or analytical solutions, are utilized to evaluate the numerical modelling tool. In many parts of the world, groundwater is an important resource for freshwater. While it is not only limited in quantity, subsurface water bodies are often in danger of contamination from various natural or anthropogenic sources. Especially in arid regions, marine saltwater intrusion poses a major threat to groundwater aquifers which mostly are the exclusive source of freshwater in these dry climates. In contrast to common numerical groundwater modelling, density-driven flow and mass transport have to be considered as vital processes in the system and in scenario simulations for fresh-saltwater interactions. In the beginning of this thesis, the capabilities of the modelling tool OpenGeoSys are verified with selected benchmarks to represent the relevant non-linear process coupling. Afterwards, variable-density application and process studies on different scales are presented. Application studies comprehend regional groundwater modelling of a coastal aquifer system extensively used for agricultural irrigation, as well as hydro-geological model development and parametrization. In two process studies, firstly, a novel method to model gelation of a solute in porous media is developed and verified on small scale laboratory observation data, and secondly, investigations of thermohaline double-diffusive Rayleigh regimes on medium scale are carried out. With the growing world population and, thus, increasing pressure on non-renewable resources, intelligent management strategies intensify demand for potent simulation tools and development of novel methods. In that way, this thesis highlights not only OpenGeoSys’ potential of density-dependent process modelling, but the comprehensive importance of variable-density flow and transport processes connecting, both, avant-garde scientific research, and real-world application challenges.:Abstract Zusammenfassung Nomenclature List of Figures List of Tables I Background and Fundamentals 1 Introduction 1.1 Motivation 1.2 Structure of the Thesis 1.3 Variable-Density Flow in Literature 2 Theory and Methods 2.1 Governing Equations 2.2 Fluid Properties 2.3 Modelling and Visualization Tools 3 Benchmarks 3.1 Steady-state Unconfined Groundwater Table 3.2 Theis Transient Pumping Test 3.3 Transient Saltwater Intrusion 3.4 Development of a Freshwater Lens II Applications 4 Extended Inverse Distance Weighting Interpolation 4.1 Motivation 4.2 Extension of IDW Method 4.3 Artificial Test and Regional Scale Application 4.4 Summary and Conclusions 5 Modelling Transient Saltwater Intrusion 5.1 Background and Motivation 5.2 Methods and Model Setup 5.3 Simulation Results and Discussion 5.4 Summary, Conclusion and Outlook 6 Gelation of a Dense Fluid 6.1 Motivation 6.2 Methods and Model Setup 6.3 Results and Conclusions 7 Delineating Double-Diffusive Rayleigh Regimes 7.1 Background and Motivation 7.2 Methods and Model Setup 7.3 Results 7.4 Conclusions and Outlook III Summary and Conclusions 8 Important Achievements 9 Conclusions and Outlook Bibliography Publications Acknowledgements Appendix info:eu-repo/classification/ddc/550 ddc:550

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