Tomatoes are widely produced and consumed due to their nutritional content and versatility. However, the tomato is a soft fruit liable to damage and flavour deterioration. Hence, the main challenge for the tomato producing industry is to prevent the high loss incurred during harvest, handling and transportation of the crops. The objective of this study was to investigate the overall nutritional implication of controlled storage of tomatoes using ozone on the ripening process and the basic nutritional components of tomatoes. This investigation was also designed to focus on the effect of different ozone doses on the basic components and properties (carotenoids, ascorbic acid, total antioxidant activity and soluble sugars content) of the quality and dynamic maturity of tomatoes. Green tomatoes (Rio Grande) were treated in glass chambers with ozone enriched air [(air + 2, 7 and 21 mg O3/g tomato) and control (air only)] under humidity and temperature of 90-95% and 14-17 oC respectively. Tomatoes were sampled after 14 days of ozone treatment in the storage chamber and analyzed for different quality parameters (appearance, weight loss, Total Soluble Solids (TSS), titratable acidity, total ascorbic acid and carotene) of the ripening. The variety Elegance tomatoes were selected and the fruits were graded by colour and subjected to treatment with ozone (in doses 0 (clean air), 0.25, 0.50, and1.00 mg O3/g tomatoes) during storage for 6 days under the same humidity and temperature conditions. The fruits were analysed for carotenoids, ascorbic acid content, total antioxidant activity and soluble sugars.Analysis of the fruits clearly showed that ozone significantly delayed the development of colour on the surface, particularly in the low doses, and caused black spots on the surface of the tomatoes, particularly in higher ozone doses. Ozone did not affect the ascorbic acid and titratable acidity content. However ozone did reduce the Total Soluble Solids (TSS) by about 10% at the lowest ozone dose. A high inhibition of accumulation of carotenoids, particularly at low dose, of the tomatoes (Rio Grande) was also observed. Tomatoes (Elegance) under ozone treatments contained higher ß-carotene than those under the control treatment and lycopene content increased during storage in the red stage of tomato fruits. Ascorbic acid (AsA), dehydroascorbic acid (DHA) and the total of AsA and DHA concentrations, and ratios of redox (ASA/ (ASA + DHA) and DHA/AsA in pericarp and pulp of tomatoes tissue, did not show clear differences between the different treatments. The concentrations of the glucose and fructose increased in the tomatoes which were subjected to ozone treatments. Results from this study show that controlled atmosphere storage of tomatoes using ozone is a viable technique which warrants further study. / Libyan government

Consumption continues to grow, while warnings persist about the fact that more isbeing consumed than the Earth is capable of yielding. This growth in consumption isclearly exemplified in the textile industry, which doubled global fibre productionbetween the years 2000 and 2020, while the population growth was 27% (The WorldBank, 2022). The textile industry is not limited to fashion; it has a wide range ofapplications and sources. However, all materials and industries come with their ownenvironmental challenges, such as land use, water consumption and chemical release,which all have an impact on nature. Life Cycle Assessment (LCA) is a method used tomeasure and compare these challenges between products. One of the resources that ismeasured is biodiversity, which is affected by land use. Various models to measurethese effects have been developed by researchers such as Lindeijer (2000), Milá i Canalset al. (2007) and Koellner &amp; Scholz (2008).This study aims to evaluate the effects on the land's ability to reproduce itself bycomparing the plants that can produce two common textile fibres from two types ofland: cotton from agricultural land and viscose from forestry land. The study analysesthe resources required and determines which fibre is the most sustainable in terms ofresource extraction in land, water and chemical use.Two LCA methods were chosen. The primary method is based on data selected by theauthor through literature studies, conversations and statistics, termed the ExplorativeLCA. The second method, the benchmark method, utilized a standardized databaseLCA provided by Ecoinvent, ReCePi and Simapro named Database LCA. The resultsobtained from the two methods stated significant and unexpected differences,encouraging the need for a more in-depth analysis to understand the reasons behindthem.According to the Exploratory LCA the results of the thesis and research questionsindicate that cotton is the preferable fibre compared to viscose. Conversely, theDatabase LCA presents the opposite findings. The results of the method analysisindicate that the integration of different plant cycles was not taken into account. Thisfinding leads the author to strongly recommend to further investigate this limitation / <p>2023-10-11</p>

Timber and wildlife habitat management may be conflicting objectives, but both benefit from increasing light in bottomland forests through harvesting and midstory control, and a target residual basal area may be used to optimize both. Six areas were used to evaluate effects of partial harvest and midstory control on oak regeneration, diameter growth of residual trees, and white-tailed deer carrying capacity. Partial harvest treatments consisted of residual basal areas of 70ft2/ac (16.07m2/ha), 60ft2/ac (13.77m2/ha), 50ft2/ac (11.48 m2/ha), 40ft2/ac (9.18m2/ha), 30ft2/ac (6.89m2/ha), and untreated controls. All partial harvest areas received midstory control using injection with imazapyr. Available light was related to residual basal area (R2 = 0.808). Treatments with 50ft2/ac residual basal area exhibited the optimal amount of oak regeneration and white-tailed deer carrying capacity. Treatments with 30ft2/ac had greatest diameter growth. This research provided guidelines for managers that wish to optimize white-tailed deer habitat and oak regeneration.

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Current eastern wild turkey (<I>Meleagris gallopavo silvestris</I>) harvest models assume density-independent population dynamics despite indications that populations are subject to a form of density dependence. I suggest that both density-dependent and independent factors operate simultaneously on wild turkey populations, where the relative strength of each is governed by population density. I attempt to estimate the form of the density dependence relationship in wild turkey population growth using the theta-Ricker model. Density-independent relationships are explored between production and rainfall and temperature correlates for possible inclusion in the harvest model. Density-dependent and independent effects are then combined in the model to compare multiple harvest strategies. To estimate a functional relationship between population growth and density, I fit the theta-Ricker model to harvest index time-series from 11 state wildlife agencies. To model density-independent effects on population growth, I explored the ability of rainfall, temperature, and mast during the nesting and brooding season to predict observed production indices for 7 states. I then built a harvest model incorporating estimates to determine their influence on the mean and variability of the fall and spring harvest. Estimated density-dependent growth rates produced a left-skewed yield curve maximized at ~40% of carrying capacity, with large residuals. Density-independent models of production varied widely and were characterized by high model uncertainty. Results indicate a non-linear density dependence effect strongest at low population densities. High residuals from the model fit indicate that extrinsic factors will overshadow density-dependent factors at most population densities. However, environmental models were weak, requiring more data with higher precision. This indicates that density-independence can be correctly and more easily modeled as random error. The constructed model uses both density dependence and density-independent stochastic error as a tool to explore harvest strategies for biologists. The inclusion of weak density dependence changes expected harvest rates little from density-independent models. However, it does lower the probability of overharvest at low densities. Alternatives to proportional harvesting are explored to reduce the uncertainty in annual harvests. / Ph. D.

The purpose of this research was to evaluate current management strategies for the New River, Virginia, muskellunge Esox masquinongy fishery, which is the premier muskellunge fishery in the state. The primary objectives were to evaluate potential benefits and angler support for more restrictive harvest regulations and to quantify habitat selection at multiple spatial scales. A secondary objective was to develop an alternative procedure for testing differences in muskellunge condition from relative weight Wr data that incorporates uncertainty regarding the accuracy of the standard weight equation and that is based on derived statistical properties of the Wr index. Abundance of memorable-length (³1,070 mm) muskellunge was predicted to increase with minimum length limits of 914, 1,016, and 1,143 mm. Although yield per recruit would decline under a 1,143-mm minimum length limit, it was predicted to remain fairly stable at length limits of 914 and 1,016 mm due to fast growth rates of young fish. Even though most anglers defined trophy muskellunge to be in excess of 1,016 mm, angler support for length limits in excess of 1,000 mm was low. Habitat variables that were most strongly related to muskellunge habitat selection were measures of patch shape complexity and water depth. Increased river discharge was found to significantly affect muskellunge habitat use and selection, with fish abandoning deeper open-water habitats and moving to shallower areas closer to the shoreline during periods of high discharge. As for the secondary objective, a new statistical test (R-test) was developed that can be used to test for differences in Wr between and within fish stocks. Comparison with other statistical tests indicated that the R test provides more conservative results than traditional statistic procedures, and that substantial variability in standard weight equations will make it more difficult to detect statistical differences. Management recommendations for the New River muskellunge fishery include increasing the minimum length limit to approximately 965 to 1,067 mm and limiting the stocking of muskellunge only to those areas with sufficient juxtaposition of shallow- and deep-water habitat patches. / Ph. D.

I investigated ruffed grouse (Bonasa umbellus) population ecology in the southern and central Appalachians as part of the Appalachian Cooperative Grouse Research Project (ACGRP). Several hypotheses have been offered to explain the low abundance of ruffed grouse in the region including inadequate quantity of early-successional forests due to changes in land use, additive harvest mortality, low productivity and recruitment, and nutritional stress. Through the cooperative nature of the ACGRP, researchers tracked >3,000 ruffed grouse between October 1996 and September 2002 and gathered data on reproduction, recruitment, survival, and mortality factors. As part of the ACGRP My objectives were (1) estimate reproductive rates, (2) estimate survival and cause-specific mortality rates, (3) determine if ruffed grouse harvest in the Appalachian region is compensatory, and (4) estimate ruffed grouse finite population growth. Ruffed grouse population dynamics in the Appalachian region differed greatly from the core of ruffed grouse range. In general, ruffed grouse in the Appalachian region had lower productivity and recruitment, but higher survival than reported for populations in the Great Lakes and southern Canada. However, within the southern and central Appalachian region, ruffed grouse population dynamics differed between oak-hickory and mixed-mesophytic forest associations. Productivity and recruitment were lower in oak-hickory forests, but adult survival was higher than in mixed-mesophytic forests. Furthermore, ruffed grouse productivity and recruitment were more strongly related to hard mast (i.e., acorn) production in oak-hickory forests than in mixed-mesophytic forests. The leading cause of ruffed grouse mortality was avian predation (44% of known mortalities). Harvest mortality accounted for only 12% of all known mortalities and appeared to be compensatory. Population models indicate ruffed grouse populations in the Appalachian region are declining, but estimates vary greatly stressing the need for improved understanding of annual productivity and recruitment. We posit ruffed grouse in the Appalachian region exhibit a clinal population structure and changes in life-history strategies due to gradual changes in the quality of food resources, changes in snow fall and accumulation patterns, and predator communities. Recommendations are presented for habitat and harvest management and future research and management needs. / Ph. D.