Over the past century tree encroachment has occurred in North American subalpine meadows. Causes of tree establishment have been related to climate influences and exclusion of fire, but very few studies have looked at the consequence of tree encroachment on meadow vegetation. Within the southern Canadian Rocky Mountains, Waterton Lakes National Park and Castle Special Management Area, 14 meadows were randomly selected at wet and dry sites. Nonmetric multidimensional scaling showed that species composition changed during the transition of open meadow to forest for both wet and dry habitats. There were no significant differences in these two management areas in terms of conifer encroachment and the effects on meadow species. Results of this study show that conifer encroachment has increased over the last century with the consequences of loss in meadow species through a decrease in abundance, richness and diversity. Wet sites were significantly more sensitive to conifer encroachment than dry sites. The greatest inhibitory effects of trees on meadow vegetation within the ecotone occurred when trees were 54-72 years old for wet sites and 77-112 years old for dry sites. Ecological restoration of these meadows is important for ongoing habitat conservation, maintaining species and landscape diversity and ecosystem resilience.

Student Number : 9903228W - MSc dissertation - School of Molecular and Cell Biology - Faculty of Science / Plant populations show an ability to survive and adapt under varying environmental conditions. Adaptation to heavy metal contaminated soils usually results in a decrease in genetic variation. Slimes dams consist of the pulverized rock slurry left after the extraction of gold or uranium. High toxicity levels mean that these wastes often remain uncolonised and are therefore easily eroded through wind or water. Plant populations that will be viable for long-term vegetation of slimes dams will prevent erosion, and stabilise and improve the quality of the soil. Indigenous, locally adapted species are the most likely to be successful candidates for vegetation. Indigenous, slimes-tolerant species Indigofera adenoides and Indigofera zeyheri were therefore studied. The aim was to determine if plant populations show local adaptation to the adverse substrate conditions emanating from slimes dams, by investigating genetic and morphological variation between adjacent populations growing at different distances in relation to slimes dams. The AFLP technique was used to analyse genetic variation as it produces rapid results, is inexpensive, reproducible, and capable of screening the entire genome. Lower genetic diversity was observed in those areas of the dams with higher levels of slimes-associated contamination. This difference was observed in both species, and for all measures of genetic diversity (Shannon’s information index, Nei’s gene diversity, percentage of loci polymorphic). This may be due to a founder effect following colonisation, natural selection, flowering time differences, or a combination of these factors. Reduced morphological variation was observed in those areas of the dams with higher levels of slimes-associated contamination. Significant morphological differences were observed between groups of plants from different areas, some of which appear to have the capability to assist the plants in a slimes-contaminated environment. Some degree of adaptation to slimes-contaminated soil therefore seems to have occurred, with this being more pronounced in Indigofera adenoides, although it cannot be determined whether this is purely phenotypic, or a combination of phenotypic and genetic. These species therefore seem suitable as candidates for vegetation of slimes dams, although further work must be done to fully understand the effect of slimes-associated toxicity.

Video summarizing Ph.D. dissertation for a non-specialist audience. / Civil and Environmental Engineering / College of Engineering

The restoration of drained afforested blanket bogs is a cost-effective management approach in peatland conservation that aims to restore key ecosystem functions such as biodiversity and carbon storage and sequestration. Although arthropods are one of the most abundant and widespread animal groups in peatlands, little research has been carried out to assess their response to the variety of restoration management techniques that have been applied in afforested blanket bogs. We assessed the effectiveness of restoration by investigating the restoration trajectory of arthropod assemblages in formerly afforested blanket bog. We first looked at the long-term trajectory of arthropod assemblages, as well as carabid and moth taxa, in a chronosequence of tree-felled/drain-blocked treatments. Then, we looked at the short-term response of arthropod and carabid assemblages in treatments under varying regimes of brash management. General arthropod assemblages, and the functional traits of carabids and moths, were used to further investigate what type of biotic and abiotic parameters might be of importance during restoration. Lastly, we looked at potential biondicators of restoration progress to be used in restoration monitoring. The long-term restoration trajectory showed that typical bog assemblages are yet to be achieved due to persistence of generalists, as well as absence of bog specialists. Divergence in assembly trajectory was found at 18 years since onset of restoration, suggesting the emergence of an alternative state. Short-term restoration shows that brash might act as temporary habitat at early stages, where carabids favour lower structurally complex habitats than arthropods. Broad patterns of moth distribution revealed trait syndromes associated with blanket bog, whilst abiotic components such as vegetation structure, temperature, plot perimeter and blanket bog connectivity were found to be key for arthropod assemblages. The latter suggests potential legacy and edge effects associated with the restoration process. Arthropods and carabids showed high habitat specificity and fidelity, providing high bioindicator potential for restoration progress. This thesis shows that typical bog arthropod assemblages largely rely on habitat microstructure, particularly Sphagnum mosses, and associated microclimates for survival. Management can provide temporary refuge for arthropods, but the re-establishment of peat-forming vegetation and water table depth is essential for the return of typical bog assemblages. Though trade-offs might be encountered in the long-term restoration of peatland functions, a restoration framework is provided for the monitoring of arthropod assemblages.

Typescript (photocopy). / Digitized by Kansas Correctional Industries

Great swaths of Southeastern Louisiana are drowning, land giving way to water at an alarming rate. Since the 1920s, Louisiana has lost more than 1,800 square miles of wetlands to open water, an area about the size of the state of Delaware. In the same amount of time it takes to watch an episode of Breaking Bad, our state loses the equivalent of a football field’s-worth of solid ground to the rising seas. My thesis is the first part of an accessible creative nonfiction book that tells the story of what’s happening in my home state. To what extent is it feasible to engineer ourselves out of harm’s way? What communities get relocated, and on whose terms? Most centrally, how will we address the troubling gulf between what we know to be true about our changing climate and what we are willing to do about it?

acase@tulane.edu / Ecogeomorphology is the study of interactions and feedbacks between the physical surface processes and biological communities in an ecosystem. These interactions are under-studied in wetlands associated with river deltas, and are of vital importance to the deteriorating wetlands of South Louisiana. As the state of Louisiana implements its Comprehensive Master Plan for a Sustainable Coast, which relies heavily on diverting Mississippi River water in order to create new wetlands, a detailed understanding of ecogeomorphological relationships is required to create accurate predictive models to design and assess future projects. This research is comprised of three studies of such relationships in the West Bay Sediment Diversion near Venice, LA, and has resulted in the following key findings: 1) the composition of the buried seed bank suggests a shift from river-derived to within-system propagules as the marsh develops, 2) emergent plant roots increase the cohesion of marsh soils, especially when grasses, sedges, and woody species dominate the vegetation, and 3) a competition experiment between the native sedge Schoenoplectus deltarum and the invasive grass Phragmites australis indicated that the two species performed approximately equally in mixture, regardless of abiotic stressors, while the stressors did affect productivity of each species grown in monoculture. These three studies are unified by the role of wetland vegetation as an increasingly important autogenic modifier of other wetland processes during the early development of the marsh. / 1 / Alexander D Ameen

Vacuum harvested peatlands typically do not spontaneously regenerate peatland species and more importantly the peat-forming Sphagnum mosses. Thus harvested and abandoned peatlands require restoration to return the peat-forming Sphagnum moss to the ecosystem. Restoration can create a hydrological environment that is suitable for peatland species’ regeneration and results in substantial Sphagnum moss growth. Bois-des-Bel was restored in the winter of 1999 and studied in the following three years (2000-2002), then again after 10 years (this study). Immediately following restoration the conditions were deemed favourable for Sphagnum regeneration (i.e. soil water pressures and water tables, > -100 cm and -40 cm respectively) (~ 15-20 cm in 10 years), while evaporation from the surface was reduced due to the straw mulch that was applied as part of the restoration measures. Although the hydrological conditions were suitable for peat revegetation, Bois-des-Bel was still a net exporter of carbon during first three years. The purpose of this thesis is to understand the hydrological evolution of Bois-des-Bel since the initial assessments and document the hydrophysical properties that could limit net carbon sequestration. This is done with a combination of field and laboratory (monolith) experiments through comparison of its hydrology and hydraulic parameters to that of a natural reference site. Since the initial assessment a water table rise of ~ 5-10 cm has occurred at the Restored site with an average water table of -27.3 (± 14.9) with respect to the cutover peat (pre-restoration surface) and ~ -42.3 (± 20.9) cm with respect to the regenerated Sphagnum surface. This water table is still much further from the capitula and more variable than at the Natural site (33.2 ± 9.0 cm). Both evapotranspiration (242 mm) and runoff (7 mm) from the Restored site maintained the same relationships in 2010 as during the initial assessments, compared to the Unrestored site (290mm and 37 mm, respectively). Although lower evapotranspiration equated to less water lost from the system, evapotranspiration at the Restored site was not indicative of the Natural site (329 mm), chiefly due to limited surface Sphagnum moisture at the Restored site. After ten years following restoration, the large scale hydrological processes are still controlled by the cutover peat and not the regenerated Sphagnum moss; thus the Restored site is still divergent from the Natural site. Wells paired with the soil moisture measurements resulted in average water tables of -53.7 ± 17.8 cm at the Restored site and -31.9 ± 8.3 cm at the Natural site. In addition to much lower water tables, the upper layers of regenerated Sphagnum (θ2.5 cm – 0.12 and θ7.5 cm – 0.11) on average were far drier than the same species at the Natural site (θ2.5 cm – 0.23 and θ7.5 cm – 0.32) under only Sphagnum. Furthermore the Restored site was very dry just above the cutover peat (θ17.5 cm – 0.19), compared to the same probe depth at the Natural site (0.57). At the Natural site under ericaceous and Sphagnum the soil moisture contents were generally double that of the Sphagnum-only site. In addition to poor soil water retention at the Restored site, high specific yield was observed in the Restored site (0.44) monoliths while the water table fluctuated within the Sphagnum compared to both the Natural (0.10) and Unrestored (0.05) monoliths. These retention characteristics at the Restored site are due to far lower fraction of water filled pores for a given pore diameter than the same species (S. rubellum) at the Natural site. The high abundance of large pores do not generate the necessary capillary force to draw water from the relatively wet cutover peat into the Sphagnum moss, resulting in a capillary barrier. Although after ten years the Restored section of Bois-des-Bel had somewhat representative bog peatland ecology, the hydrological conditions needed for net carbon sequestration were not present. The lack of water transmission from the cutover peat to the regenerated Sphagnum moss due to large pores and the inability of the Sphagnum moss to retain water are both retarding the restoration. For Bois-des-Bel to become a net carbon sequestering further lateral infilling of the Sphagnum leaves and branches along with decomposition of the basal layer will be need. In addition to these two processes, planting of ericaceous shrubs could lower the water loss through evaporation, thus increasing the capitula moisture content and creating healthier mosses. If Bois-des-Bel continues on its current ecohydrological trajectory it is likely that it will self-regulate and make the necessary structural changes to become a net carbon sequestering system.

Best practices for Restoration Ecology have been largely derived from case studies. Novel Ecosystems is an approach that has the possibility of providing the field of restoration research with both structure and a road map for ecological recovery. In December 2015, Ontario Parks will be ceasing the lease of approximately 122 ha of farmland within Boyne Valley Provincial Park. My thesis aims to bridge the gap between social and ecological systems and build a resilient restoration project at Boyne Valley Provincial Park. My approach integrated the best case scenarios from each the social and ecological aspects to determine a restoration plan. From the social aspect, I chose the method photo-elicitation to bridge the communication gap between myself, the researcher, and the interviewees. Semi-structured interviews were conducted with six major stakeholders including a farmer who is currently leasing land within Boyne Valley Provincial Park, a frequent hiker of the Ontario Parks’ trail system, an academic researcher for Ontario Parks, and three Ontario Parks’ personnel to understand the different landscape preferences of stakeholders within Boyne Valley Provincial Park. From the ecological aspect, I examined the success of restoration for the first year after a fall planting in terms of species richness and percent cover for all species, including native species (planted and not planted) and non-native species across three fields with different initial conditions. To test which species should be used as the initial ground cover after farming has ceased, I looked at the survivorship and growth of five species: Danthonia spicata, Elymus trachycaulus ssp. trachycaulus, Sporobolus cryptandrus, Monarda fistulosa and Penstemon hirsutus. My recommendations for restoration at Boyne Valley Provincial Park include implementing the restoration efforts at a smaller scale to start. The remaining fields should continue to be farmed until restoration can commence or mowed at least four times a year before seeds are formed. Open communication should continue between all stakeholders. Soil preparation should include tilling the soil prior to planting only if the land was left abandoned (e.g. old-field). A plant composition survey should be conducted prior to restoration – more particularly in hay fields - to determine if native meadow species are found. If native meadow species are present (e.g. Sisyrinchium montanum) that would not survive tilling, a no-till planting method may be a better option than tilling. Acknowledging these are early results, my initial recommendation based on survivorship and growth for the first year after planting would be to use plant plugs for Elymus trachycaulus ssp. trachycaulus and a combination of plant plugs and seeds for Monarda fistulosa and Penstemon hirsutus. Future studies should incorporate other herbaceous species to increase the biodiversity while choosing flowers that bloom at different times. Additionally, pilot studies should be completed at all Ontario Parks locations where agriculture leases are ending to develop restoration methodologies that are applicable across Ontario. Information on each of the species to be planted should be distributed to the farmers that border Ontario Parks’ boundaries. This information should include at minimum the species life history, dispersal mechanisms, and a photograph. The research in this thesis outlines initial restoration efforts to guide restoration recommendations for the first year after land abandonment. Much longer-termed research is necessary to understand community dynamics and potential recovery of system.

The development of graduate students in the sciences preparing for careers in academia has long included elements to advance students as science researchers, but recent emphasis is being placed on developing students as instructors and education researchers as well. As such, objectives of this study included assessments of seedling responses to hydrology typical of floods in urban settings, the role of created microtopography in community development of a bottomland hardwood forest, and the influence of geographic information systems (GIS) on student motivation and conceptual knowledge. Substantial losses of bottomlands in Texas necessitate restoration to regain the ecosystem services that they provide. Restoration of proper hydrology is the most important aspect of wetland restoration, but this can prove difficult in urbanizing environments where hydrology has been irreversibly altered. Microtopography has been shown to be an important component of bottomland hardwood forests, and its restoration may aid in hydrologic restoration as gradients are created that support a diverse community. Tree seedlings were subjected to experimental flooding regimes typical of floodplain forests in rural and urban settings. Growth rates of seedlings varied over time and differed depending on species and treatment. Created microtopography resulted in a spatially heterogeneous system similar to that of natural bottomlands and strongly influenced hydrology, soil properties, survival of planted seedlings, and abundance and distribution of colonizing species. Proper bottomland restoration in urbanizing environments should include species selection based on current and potential future hydrologic conditions. In addition, restoring microtopography may improve survival of a variety of species introduced during restoration, as well as enhance colonization of a diverse plant community under changing hydrologic regimes. Trends indicated a slight improvement in attitude and performance for students that used GIS. More important, the authenticity of the experience appeared to affect student attitude. The effective use of GIS in teaching may be scale-dependent. Smallscale phenomena may be assessed as easily in a field exercise as with GIS. Using GIS to assess large-scale, complex patterns may have a substantial impact on student understanding. Further studies are needed to determine direct benefits of teaching with GIS in undergraduate ecology classrooms.