Forest Biomass Utilization in the Southern United States: Resource Sustainability and Policy Impacts

As an alternative renewable source for bioenergy, forest biomass has recently drawn more attention from the U.S. government and the general public. Woody biomass policies have been adopted to encourage the new bioenergy industry. A variety of state policy incentives attempt to create a desirable legal climate and lure new firms, imposing two important questions regarding state government policies and the sustainable use of forest resources. This dissertation sheds some light on these questions. The first paper constructs a woody biomass policy index through scoring each statute and weighting different categories of policies from the vantage point of renewable energy investment. It analyzes the disparity in the strength of state government incentives in the woody biomass utilization. The second paper employs a conditional logit model (CLM) to explore the effects of woody biomass policies on the siting decisions of new bioenergy projects. In addition, significant state attributes influencing the births of new bioenergy firms are identified such as resource availability, business tax climate, delivered pulpwood price, and the average wage rate. The third paper uses the Sub-Regional Timber Supply (SRTS) model to examine the regional aggregate forest biomass feedstock potential in Tennessee and to predict the impacts of additional pulpwood demand on the regional roundwood market through 2030. The fourth paper includes the benefits of thinning and logging residues in a dynamic optimization model to analyze how bioenergy policies will impact forest stock, harvest levels, optimal rotation, and silvicultural effort. The results may have substantial implications regarding woody biomass policies, the creation of a new bioenergy industry, and sustainable forest resource management. A lucrative state woody biomass policy support and tax climate can attract new bioenergy businesses. States endowed with abundant forest resources may choose to provide strong tax incentives to spur the birth of new plants. However, overuse of forest biomass can impact roundwood markets and traditional wood processing industries. How government incentives will affect the sustainability of natural resources can be diverse. These findings offer constructive insights in the enactment and implementation of new woody biomass legislation

Enhancing the Electricity Generation and Nitrate Removal of Microbial Fuel Cells With a Novel Denitrifying Exoelectrogenic Strain EB-1

Microbial fuel cells (MFCs) have been tentatively applied for wastewater treatment, but the presence of nitrogen, especially nitrate, induces performance instability by changing the composition of functional biofilms. A novel denitrifying exoelectrogenic strain EB-1, capable of simultaneous denitrification and electricity generation and affiliated with Mycobacterium sp., was isolated from the anodic biofilm of MFCs fed with nitrate containing medium. Polarization curves and cyclic voltammetry showed that strain EB-1 could generate electricity through a direct electron transfer mechanism with a maximum power density of 0.84 ± 0.05 W m−2. Additionally, anodic denitrification, as a concurrent metabolism, was demonstrated with an efficient removal rate of 0.66 ± 0.01 kg N m−3 d−1 at a COD/N ratio of 3.5 ± 0.3. Importantly, voltage output was not negatively influenced by nitrate, indicating that the concurrent process of nitrate removal and electricity generation was a limitation of the electron donor rather than an inhibition of the system. Furthermore, various organic materials were successfully utilized as anode donors for strain EB-1, and demonstrated the exciting performances in terms of simultaneous denitrification and electricity generation. Mycobacterium sp. EB-1 thus expands the diversity of exoelectrogens and contributes to the potential applications of MFC for simultaneous energy recovery and wastewater treatment

Factors Affecting Temporal and Spatial Variations of Microcystins in Gonghu Bay of Lake Taihu, with Potential Risk of Microcystin Contamination to Human Health

A field survey of the seasonal variation of microcystin (MC) concentration was performed in Gonghu Bay (a total of 15 sampling sites) of Lake Taihu from January to December 2008. Microcystis spp. biomass and intra-/extracellular MCs were significantly correlated with water temperature, suggesting the importance of temperature in cyanobacterial blooming in the lake. Higher MC concentration was found in summer and autumn, and peaks of Microcystis biomass and intra-/extracellular MC concentrations were all present in October. Spatially, risk of MCs was higher in littoral zones than in the pelagic area. There were significant correlations between N or P concentrations, and Microcystis biomass or MC content, suggesting that N and P levels affected MC production through influencing Microcystis biomass. Intra-/extracellular MCs and Microcystis biomass had negative exponential relationships with TN:TP, and the maximum values all occurred when TN:TP was <25. Multivariate analyses by PCCA indicated that intra- and extracellular MC concentrations had better correlations with biological factors (such as Microcystis biomass and chl-a) than with physicochemical factors. The maximum MC concentration reached up to 17 mu g/L MC-LReq, considerably higher than the drinking water safety standard (1 mu g/L) recommended by the WHO. So it is necessary to take measures to reduce the exposure risk of cyanobacterial toxins to human beings

Revisiting the built environment: 10 potential development changes and paradigm shifts due to COVID-19

This study explores potential development and paradigm shifts in two main sectors of construction and the built environment due to COVID-19. These development changes are discussed based on evidence from previous pandemics, current and expected impacts on both industries, and how they are likely to shape the next policy, practices, and perspectives. By assessing the primary areas of both sectors through an expert-led analysis, this study suggests 10 potential development changes that we could expect in the post-COVID time. These potential changes are discussed as possible new practices, empowered regulations, or adaptive measures; and eventually towards paradigm shifts. A total of 50 participants contributed to the selection, identification, and assessment of these potential changes. The findings from this study feed into the assessment of ongoing and forthcoming changes as a result of the current pandemic, specifically on two sectors of ‘construction’ and ‘the built environment’. These will include paradigm shifts in architecture practices, civil engineering practices, project management, and urbanism. Some of the suggestions in this study may harness shared practices, and some may simply develop into new forms of development practices in both sectors

Economic and policy perspectives of biofuel as an emerging use of forest biomass in Mississippi

Renewable energy has been developing rapidly in the U.S. over the past decades. This thesis first reviewed the status, challenges, and government policies related to the development of bioenergy products from forest-derived woody biomass. Forest management alternatives of loblolly pine (Pinus taeda) plantations for producing both timber and biofuels were then evaluated using economic and biological criteria. The PTAEDA3.1 computerized yield simulator was used to predict growth effects of various site preparation techniques, initial planting densities, and thinning activity. Results indicated that on Site Index 50 to 70 lands, the average annual yields of stem residues ranged from 0.86 to 1.20 tons per acre, from which 39.8 to 47.4 gallons of ethanol could be produced. The rise of relative biomass price would increase wood availability for biofuels. It will also boost intensive management practices, such as intensive site preparation, closer initial planting spacing, earlier thinnings and a shorter harvesting age

The Evolution of the Coastal Economy: The Role of Working Waterfronts in the Alabama Gulf Coast

This article describes the evolution of the coastal economy in Alabama and examines the driving forces of the sustainable economy in a historical context. The input-output model was applied to assess the direct and secondary effects of output and employment in the coastal region. Results suggest that state industries are heavily dependent on waterfront-related activities in this area, which have fueled much of their rapid development in the past few decades. Tourism, ship building and repairing and transportation are the three dominating sources contributing to the coastal economy. There are a few general problems of working waterfronts in the coastal Alabama area, but there are also some unique problems (e.g., Hurricane Katrina, Deepwater Horizon oil spill). Policies for future sustainable development are proposed

Novel KDM6A splice-site mutation in kabuki syndrome with congenital hydrocephalus: a case report

Abstract Background Kabuki syndrome (KS) is a rare congenital anomaly syndrome affecting multiple organs. Two genes have been shown to be mutated in patients with KS: lysine (K)-specific demethylase 6A (KDM6A) and lysine (K)-specific methyltransferase 2D (KMT2D, formerly MLL2). Although the congenital clinical characteristic is helpful in diagnosis of the KS, there are no reports of specific findings in fetuses that might suggest the syndrome prenatally. Case presentation In this study, we described a male patient with a novel KDM6A splicing in exon(exon4) and flanking intron(intron3)-exon boundaries characterized by congenital hydrocephalus which had never been reported before. The male patient had inherited the c.335-1G > T splice site mutation from his mother who had fewer dysmorphic features than the patient who displayed a more severe phenotype with multiple organ involvement. Our research suggests that congenital hydrocephalus may accompany KS type 2, which improve the knowledge on KS further more. Conclusions Based on genetic and clinical features, suggest that the c.335-1G > T splicing mutation in KDM6A causing KS-2 disease. At least for this case, we suggest that congenital hydrocephalus is closely associated with KS type 2