These photos are provided in order to more fully illustrate and explain the Zion and Pipe Spring technical report.

This dissertation presents four microbial microcosm-based experimental studies addressing questions related to the causes and consequences of biodiversity. All four studies adopted an approach that integrates ecology and evolutionary biology. Two studies explored the utility of knowledge on species phylogenetic relationships for understanding community assembly (chapter 1) and invasibility (chapter 3). The other two studies investigated the impacts of important ecological factors, including competition (chapter 2) and temporal niches (chapter 4), on adaptive radiation, using the rapidly diversifying bacterium Pseudomonas fluorescens SBW25 as the model organism. The first study, described in Chapter 1, examined how phylogenetic relatedness between competing species affected the strength of priority effects and ecosystem functioning during community assembly. Strong priority effects emerged only when competing bacterial species were phylogenetically most closely related, resulting in multiple community states associated with different assembly histories. In addition, the phylogenetic diversity of bacterial communities effectively predicted bacterial production and decomposition. The second study, described in Chapter 2, explored the role of competition in the adaptive radiation of P. fluorescens. The adaptive radiation was generally suppressed by competition, but its effect was strongly modulated by the phylogenetic relatedness between the diversifying and competing species and their immigration history. The inhibitive effect of competition on adaptive radiation was strongest when phylogenetic relatedness was high and when competitors were introduced earlier. The third study, described in Chapter 3, evaluated the relative importance of phylogenetic relatedness between resident and invading species and phylogenetic diversity of resident communities for invasibility. Laboratory bacterial communities containing a constant number of resident species with varying phylogenetic diversity and relatedness to invaders were challenged by nonresident bacterial species. Whereas invader abundance decreased as phylogenetic relatedness increased as predicted by Darwin's naturalization hypothesis, it was unaffected by phylogenetic diversity. The final study, described in Chapter 4, presented the first experimental demonstration of the maintenance of biodiversity that emerged from adaptive radiation in the presence of temporal niches. Only when provided with temporal niche opportunities were multiple derived phenotypes of P. fluorescens able to coexist as a result of negative frequency-dependent selection. When temporal niche was absent, the specialized phenotypes either did not emerge or were predominated by one superior phenotype.

No description available.

Rangelands are a major type of land found on all continents. Though they comprise around 70% of the world's land area, knowledge of rangelands is limited and immature. Rangelands supply humans with food and fiber at very low energy costs compared to cultivated lands. They are inherently heterogeneous, highly variable in time and space. Rangeland management needs to consider the impacts of long-term vegetation transition. It needs a conceptual framework defining potential vegetation communities, describing the management induced transition of one vegetation community to another, and documenting the expected benefits provided by the various potential vegetation communities. The most widely used conceptual unit in the rangeland discipline is the "ecological site". Ecological sites can be an effective unit that should respond to management consistently and can help managers understand the site's potential to meet human needs. A state and transition model (STM) brings ecological sites and their potential vegetative states together to build a conceptual framework showing the major causes of transitions between states of an ecological site and thus helping make adaptive management decisions. Within the STM there is a need for an indicator of ecosystem health. Ecosystem services can be important to evaluate alternative states. Ecosystem services do not pass through a market for valuation, though often the cost would be very high if, through mismanagement, the ecosystem is no longer capable of providing those services. Vegetation communities are constantly facing reversible or irreversible transitions triggered by natural events and/or management actions. The framework generated in this study is significant in using remote sensing to generate state and transition models for a large area and in using ecosystem services to evaluate natural and/or management induced transitions as described in the STM. This dissertation addresses the improvement of public rangelands management in the West. It applies geospatial technologies to map ecological sites and states on those sites, characterizes transitions between states and selects a desired state to manage towards based on a systematic assessment of the value of flows of environmental services. The results from this study are an evaluation of improved draft ecological site maps for a larger area using remote sensing images, a simplified state-and-transition model adapted to remote sensing capabilities to study transitions due to climatic events and management practices, and a constrained optimization model that incorporates ecosystem services and the simplified STM to evaluate management costs and conservation benefits. The study showed that brush treatment is the most effective management practice to cause state transitions. The highest increase in the high cover state was by 24%. Areas under grazing and drought show slow transitions from brush to grass and also after prescribed fire vegetation take at least two years to recover.

Woody plant encroachment (WPE) into historic grasslands not only alters ecosystem structure but also yields a mosaic of vegetative growth-forms that differ in their inherent physiological capacities and physical attributes. C₃ plants tend to have a relatively broad range of temperature function but at the expensive of a lower optimum rate of photosynthesis. In contrast, C₄ grasses have a greater capacity for maximum uptake but across a relatively narrow range of temperatures. In considering which of these functional groups will outcompete the other within these regions undergoing WPE, one must account not only for these leaf physiological traits, but also the growth form induced differences in rooting depth, and therefore, potential access to deeper subsurface water. Laid upon these competitive interactions is an ever-changing environment, which for the semiarid southwestern US is predicted to become progressively warmer and characterized by highly variable precipitation with longer interstorm periods. In addition to aboveground changes in CO₂ assimilation, WPE influences soil nutrient, water, and carbon cycling. The objectives of this dissertation were to quantify: (1) the influence that temperature and available soil moisture have on regulating soil respiratory efflux within the microhabitats that results from WPE to estimate the influence this vegetative change will have on ecosystem CO₂ efflux; (2) the sensitivity of CO₂ uptake within grassland and woodland ecosystems to temperature and precipitation input in an effort to characterize how WPE might influence regional carbon and water balance; and (3) the role access to stable groundwater has in regulating the temperature sensitivity of ecosystems and their component fluxes. Major findings and contributions of this research include illustrating seasonal patterns of soil respiration within the microhabitats that result from WPE, such that an analysis of the relative contributions of these different components could be made. We found that soil respiration was not only consistently greater under mesquites, but that the relative contributions of these microhabitats varied significantly throughout the year, the duration of soil respiration after each rain was habitat-specific, and that the relationship between soil respiration and temperature followed a hysteretic pattern rather than a linear function (Appendix A). We found that a woodland ecosystem demonstrated a lower temperature sensitivity than a grassland across all seasonal periods of varying soil moisture availability, and that by maintaining physiological function across a wider range of temperatures throughout periods of limited precipitation, C₃ mesquites were acquiring large amounts of carbon while C₄ grasses were limited to functioning within a narrower range of temperatures (Appendix B). Finally, we found that having a connectivity to stable groundwater decoupled leaf and ecosystem scale temperature sensitivities relative to comparable sites lacking such access. Access to groundwater not only resulted in the temperature sensitivity of a riparian shrubland being nearly half that of the upland site throughout all seasonal periods, but also actual rates of net ecosystem productivity and leaf level rates of photosynthesis being dramatically enhanced (Appendix C).

To design with a changing ecosystem requires examining and understanding site dynamics, extracting guidelines for making architectural decisions and defi ning processes that allow for change. Sable Island National Park is an ideal case study to test this method because its simple and dynamic ecosystem defi nes clear guidelines and requirements for adaptation. The proposed National Park infrastructure remodels human interaction with Sable Island by replacing and remediating existing settlements. Designed to be sensitive to and participate in the island’s natural processes, the new architecture protects the delicate ecosystem and facilitates low impact visitation. The systems, spaces and experiences serve to deepen understanding of human interdependence with the environment. / The thesis is a architectural case study for designing with dynamic ecosystems. To test a methodology for designing in dynamic ecosystems, a National Park infrastructure is designed for Sable Island, Canada. The exercise requires learning from the dynamic ecosystem, extracting guidelines for making design choices and developing designs with the capacity to adapt to their surroundings.

Wetlands have been considered throughout millenniums as valuable assets due to the ecosystem services they provide for humans. However, previous research has shown that the value of wetlands has declined over the last 150 years, in parallel to the growth of agriculture. Today, society has realized the value of ecosystem services, through increased knowledge and awareness.This study focuses on the area of Byringe, 20 km southwest of Strängnäs. The aim of this study was to identify changes of wetland areas, wetland classes and ecosystem services over time. This study compared four maps covering the area, between the years 1714 to 2013. The results show that the wetland areas have increased from their initial coverage of 6.5% up to 24.4% today. This 17.9% increase corresponds to 115.3 ha. A closer examination of this 300-year transformation showed variation among the wetland classes. Marshlands showed the largest increase of 44.3ha, followed by fen with 33.5ha and bog 7.6ha. In some areas fen had been converted to bog, which is a change in carbon storage and thus climate regulation. The lakes had developed into marshland, which has caused the disappearance of fish stocks, negatively affecting the generation of food supply. The increased marshland area has also resulted in increased carbon storage and provisioning services such as fiber material from plants and bioenergy production from trees. Furthermore, the recent transformation of agricultural land into fen has generated a loss in food production services such as crops. Instead, other services have appeared in terms of climate regulation, flood protection, increased protection against erosion, water purification and support of biodiversity.

This full report presents a classification of mid-seral black spruce ecosystems in the Boreal White and Black Spruce (BWBS) and Sub-boreal Spruce (SBS) zones of British Columbia. The classification is based on a total of 122 plots sampled during the summers of 1997 and 1998. We used multivariate and tabular methods to synthesize and classify ecosystems according to the Braun-Blanquet approach and the methods of biogeoclimatic ecosystem classification. The black spruce ecosystems were classified into 8 vegetation units (associations or subassociations) and the same number of site associations. We describe vegetation and environmental features of these vegetation and site units. Vegetation and environmental tables for individual plots are given in Appendices. In addition, we also present the relationships between site index of black spruce and direct and indirect measures of site quality.

This pamphlet provides a summary of a fuller report issued under the same title.

This full report presents the first approximation of vegetation classification of trembling aspen ecosystems in interior British Columbia. The classification is based on a total of 186 plots sampled during the summers of 1995, 1997 and 1998. We used multivariate and tabular methods to synthesize and classify ecosystems according to the Braun-Blanquet approach and the methods of biogeoclimatic ecosystem classification. The aspen ecosystems were classified into 15 basic vegetation units (associations or subassociations) that were grouped into four alliances. Communities of the Populus tremuloides – Mertensia paniculata, and Populus tremuloides – Elymus innovatus alliances were aligned with the boreal Picea glauca & mariana order and were distributed predominantly in the Boreal White and Black Spruce zone; communities of the Populus tremuloides – Thalictrum occidentale alliance were also aligned with the same order, but were distributed predominantly in the Sub-Boreal Spruce zone; communities of the Populus tremuloides – Symphoricarpos albus alliance were aligned with the wetter cool temperate Tsuga heterophylla order and the drier cool temperate Pseudotsuga menziesii order and were distributed in the Sub-boreal Spruce, Interior Western Hemlock, Montane Spruce, and Interior Douglas-fir zones. We describe the vegatation and environmental features of these units and present vegetation and environmental tables for individual plots and units.