The Environmental Microbiome In A Changing World: Microbial Processes And Biogeochemistry

Climate change can alter ecosystem processes and organismal phenology through both long-term, gradual changes and alteration of disturbance regimes. Because microbes mediate decomposition, and therefore the initial stages of nutrient cycling, soil biogeochemical responses to climate change will be driven by microbial responses to changes in temperature, precipitation, and pulsed climatic events. Improving projections of soil ecological and biogeochemical responses to climate change effects therefore requires greater knowledge of microbial contributions to decomposition. This dissertation examines soil microbial and biogeochemical responses to the long-term and punctuated effects of climate change, as well as improvement to decomposition models following addition of microbial parameters. First, through a climate change mesocosm experiment on two soils, I determined that biogeochemical losses due to warming and snow reduction vary across soil types. Additionally, the length of time with soil microbial activity during plant dormancy increased under warming, and in some cases decreased following snow reduction. Asynchrony length was positively related to carbon and nitrogen loss. Next, I examined soil enzyme activity, carbon and nitrogen biodegradability, and fungal abundance in response to ice storms, an extreme event projected to occur more frequently under climate change in the northeastern United States. Enzyme activity response to ice storm treatments varied by both target nutrient and, for nitrogen, soil horizon. Soil horizons often experienced opposite response of enzyme activity to ice storm treatments, and increasing ice storm frequency also altered the direction of the microbial response. Mid-levels of ice storm treatment additionally increased fungal hyphal abundance. Finally, I added explicit microbial parameters to a global decomposition model that previously incorporated climate and litter quality. The best mass loss model simply added microbial flows between litter quality pools, and addition of a microbial biomass and products pool also improved model performance compared to the traditional implicit microbial model. Collectively, these results illustrate the importance of soil characteristics to the biogeochemical and microbial response to both gradual climate change effects and extreme events. Furthermore, they show that large-scale decomposition models can be improved by adding microbial parameters. This information is relevant to the effects of climate change and microbial activity on biogeochemical cycles

Is tilapia farming financially profitable and efficient? Policy options for sustainable farming

Tilapia (Oreochromis niloticus) is known as ?fish for the poor? due to its low market price. However, the question remains about the sustainability of this species because of high production cost and lower market price. Therefore, this study examined the financial profitability, technical efficiency and tried to find out the policy options for increasing the financial benefit of fish farmers. A total of 250 tilapia fish farmers were selected from seven tilapia producing areas of Bangladesh. To fulfill the objectives of this study, profitability, stochastic frontier production function, and sensitivity analysis were employed. Considering all selected farmers, tilapia farming found a profitable business where undiscounted BCR was only1.11. Among all cost items, only feed consists of 70 percent of the total production cost. The mean technical efficiency level of tilapia fish farmers was 85 percent, implies that by operating at full technical efficiency levels, tilapia yield could be increased from the current level of 20.98 to 24.13 tons per hectare and efficient farmers found more productive than inefficient farmers. Farmer?s financial benefit can be increased by reducing the feed price, decreasing FCR or increasing the output price. Feed price reduction or enhance the quality of feed could be effective policy options for sustaining the tilapia farming

Predicting the effect of radiation damage on dark current in a space-qualified high performance CMOS image sensor

The CIS115 is a Teledyne-e2v CMOS image sensor with 1504 × 2000 pixels of 7 μm pitch. It has a high optical quantum efficiency owing to a multi-layer anti-reflective coating and its backside illuminated construction, and low dark current due to its pinned photodiode 4T pixel architecture. The sensor operates in rolling shutter mode with a frame rate of up to 7.5 fps (if using the whole array), and has a low readout noise of ~5 electrons rms. The CIS115 has been selected for use within the JANUS instrument, which is a high resolution camera due to launch on board ESA's JUpiter ICy moons Explorer (JUICE) spacecraft in 2022. After an interplanetary transit time of over 7 years, JUICE will spend 3.5 years touring the Jovian system, studying three of the Galilean moons in particular: Ganymede, Callisto and Europa. During this latter part of the mission, the spacecraft and hence the CIS115 sensor will be subjected to the significant levels of trapped radiation surrounding Jupiter. Gamma and proton irradiation campaigns have therefore been undertaken in order to evaluate both ionising and non-ionising dose effects on the CIS115's dark current performance. Characterisations were carried out at expected mission operating temperatures (−35 ± 10oC) both prior to and post-irradiation. Models of the resulting degradation in dark current behaviour will be combined with expected doses during the JUICE mission in order to predict the performance of the CIS115 at the mission end-of-lif

Bioethanol production from coconut husk using DES-NADES pretreatment and enzymatic hydrolysis method

Bioethanol is an alternative fuel produced during biomass fermentation. Among the available biomass resources for bioethanol production, coconut husk is an interesting raw material due to its high cellulose content. This study aims to evaluate the coconut husk conversion into bioethanol using DES (ChCl:MEA) and NADES (Be:La) solvents for the delignication process. The molar ratios of HBA and HBD of the two solvents were varied (1:4, 1:6, 1:8) at 2, 4, 6, and 8 h for each ratio. The deligni- ed samples were hydrolyzed using the 5% (w/w) of cellulase enzymes and fermented for seven days using Saccharomyces cerevisiae. The results showed that DES (ChCl:MEA) and NADES (Be:La) could remove lignin at about 60.53% and 65.81%. The glucose content was obtained at 0.5% (brix) by both solvents and bioethanol content was obtained at 13.9% and 14% (v/v) for DES and NADES, respectively

Gerenciamento de resíduos de serviços de saúde em um Hemocentro do estado do Paraná

Na literatura há poucos estudos sobre resíduos de serviços de saúde (RSS) em hemocentros, o que motivou esta investigação, cujo objetivo foi diagnosticar o gerenciamento dos RSS em um Hemocentro do Paraná (HPR). Foi utilizada metodologia descritivo-exploratória, com uso de questionário, análise documental e caracterização dos RSS. Os dados revelaram produção de 224,5 kg de resíduos/semana (Grupo A-35,23%, Grupo E-10,97%, Grupo D-53,7%), com 1,36 kg de RSS por bolsa de sangue coletada, além de inadequações quanto à segregação e infraestrutura, com possíveis riscos à saúde e ambiente. O tratamento e disposição final dos RSS ocorrem a 450 km da origem. Conclui-se haver necessidade de elaboração de Plano de Gerenciamento dos RSS e adequação às atuais políticas públicas

Simulated N deposition negatively impacts sugar maple regeneration in a northern hardwood ecosystem

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/90216/1/j.1365-2664.2011.02090.x.pd

Seasonal fluxes of carbonyl sulfide in a midlatitude forest

Carbonyl sulfide (OCS), the most abundant sulfur gas in the atmosphere, has a summer minimum associated with uptake by vegetation and soils, closely correlated with CO2. We report the first direct measurements to our knowledge of the ecosystem flux of OCS throughout an annual cycle, at a mixed temperate forest. The forest took up OCS during most of the growing season with an overall uptake of 1.36 ± 0.01 mol OCS per ha (43.5 ± 0.5 g S per ha, 95% confidence intervals) for the year. Daytime fluxes accounted for 72% of total uptake. Both soils and incompletely closed stomata in the canopy contributed to nighttime fluxes. Unexpected net OCS emission occurred during the warmest weeks in summer. Many requirements necessary to use fluxes of OCS as a simple estimate of photosynthesis were not met because OCS fluxes did not have a constant relationship with photosynthesis throughout an entire day or over the entire year. However, OCS fluxes provide a direct measure of ecosystem-scale stomatal conductance and mesophyll function, without relying on measures of soil evaporation or leaf temperature, and reveal previously unseen heterogeneity of forest canopy processes. Observations of OCS flux provide powerful, independent means to test and refine land surface and carbon cycle models at the ecosystem scale.Engineering and Applied Science

High elevation watersheds in the southern Appalachians: Indicators of sensitivity to acidic deposition and the potential for restoration through liming

Southern Appalachian high elevation watersheds have deep rocky soils with high organic matter content, different vegetation communities, and receive greater inputs of acidic deposition compared to low elevation sites within the region. Since the implementation of the Clean Air Act Amendment in the 1990s, concentrations of acidic anions in rainfall have declined. However, some high elevation streams continue to show signs of chronic to episodic acidity, where acid neutralizing capacity (ANC) ranges from 0 to 20 µeq L-1. We studied three 3rd order watersheds (North River in Cherokee National Forest, Santeetlah Creek in Nantahala National Forest, and North Fork of the French Broad in Pisgah National Forest) and selected four to six 1st order catchments within each watershed to represent a gradient in elevation (849–1526 m) and a range in acidic stream ANC values (11–50 leq L-1). Our objectives were to (1) identify biotic, physical and chemical catchment parameters that could be used as indices of stream ANC, pH and Ca:Al molar ratios and (2) estimate the lime required to restore catchments from the effects of excess acidity and increase base cation availability. We quantified each catchment’s biotic, physical, and chemical characteristics and collected stream, O-horizon, and mineral soil samples for chemical analysis seasonally for one year. Using repeated measures analysis, we examined variability in stream chemistry and catchment characteristics; we used a nested split-plot design to identify catchment characteristics that were correlated with stream chemistry. Watersheds differed significantly and the catchments sampled provided a wide range of stream chemical, biotic, physical and chemical characteristics. Variability in stream ANC, pH, and Ca:Al molar ratio were significantly correlated with catchment vegetation characteristics (basal area, tree height, and tree diameter) as well as O-horizon nitrogen and aluminum concentrations. Total soil carbon and calcium (an indicator of parent material), were significant covariates for stream ANC, pH and Ca:Al molar ratios. Lime requirement estimates did not differ among watersheds but this data will help select catchments for future restoration and lime application studies. Not surprisingly, this work found many vegetation and chemical characteristics that were useful indicators of stream acidity. However, some expected relationships such as concentrations of mineral soil extractable Ca and SO4 were not significant. This suggests that an extensive test of these indicators across the southern Appalachians will be required to identify high elevation forested catchments that would benefit from restoration activities