<p> &ldquo;Biogeographic affinity&rdquo; describes the similarities in the flora and fauna of one location compared to those of another location, resulting from their common evolutionary history and/or their contemporary connectivity (Loveland and Merchant 2004). The existence of the biogeographic affinity hypothesis allows the hierarchical classification of regions into faunal, floristic or other biogeographic provinces. Additionally, the latitudinal biodiversity gradient (LBG; Brown and Lomolino 1998) is normally illustrated by a diverse tropical fauna at low latitudes and decreasing species richness with increasing latitude. Here, I compare the relative influences of biogeographic affinity and the primary ecological gradients of the southern Colorado Plateau in the Grand Canyon ecoregion (GCE, Table 2; elevation, litter accumulation, and anthropogenic influences) on the distribution and abundance of land mollusks. I test four specific null hypotheses: (1) Biogeographic affinity does not influence the distribution of GCE land mollusks, (2) GCE land mollusk species and assemblages are uniformly distributed across elevation, analogously reflecting the absence of biogeographic affinity, (3) Habitat patch size (spring area) does not influence GCE land mollusk species richness and (4) The GCE land mollusk assemblage is not strongly influenced by microhabitat factors that are independent of elevation impacts. </p><p> To test my hypotheses, I used classic and contemporary literature and museum collections to build a comprehensive species list for the Grand Canyon ecoregion. This list included spatial (location, elevation) and ecological (biogeographic affinity) data to test hypothesis 1 (proportional representation) and hypothesis 2 (neotropical to boreal distribution. across elevation). I also used randomly sampled terrestrial mollusks in three elevation zones at 19 paired spring and matrix habitat sites, while also recording environmental data on leaf litter depth, isopod presence or absence, grazing presence or absence at each sample, canopy cover and spring area at each site. These data were used to test hypothesis 3 (spring area-species diversity relationships) and 4 (measured site- specific independent variables will predict species diversity). </p><p> The results of this analyses show: 1. The GCE land mollusk fauna is not equally distributed across 7 North American Biogeographic Provinces. Instead, the GCE is overrepresented by boreal, alpine and temperate species. 2. This two-dimensional pattern of overrepresentation was preserved across (3-dimensional) elevational gradients within the GCE. Communities were at least 84% dissimilar between elevation zones, with New- World temperate and wide-ranging circumpolar species being the dominant drivers the mollusk community composition even at low elevation sites. 3. Shannon-Weiner diversity (supporting the Latitudinal Biodiversity Hypothesis) and leaf litter depth (productivity) within springs decreased with increasing elevation. 4. Among the measured physical (spring/matrix, litter depth, canopy cover, species-area) and anthropogenic (isopods, grazing) factors, elevation was the only one found to predict species community composition. </p><p> These results indicate that while springs in the southwest USA are presumed to be relictual habitats, temperate land mollusks still possess an apparent advantage over neotropical species even at low elevation springs, where they are more abundant and diverse. These data support the Latitudinal Biodiversity Gradient (LBG) in a novel and unusual way, where low elevation sites are the most diverse, but are characterized by wide-ranging temperate and boreal species, with significant community compositional change across elevation.</p><p>

<p> Many reasons have been suggested as explanation for observed differences in citizens' environmental conservation projects policy choices and willingness-to-pay (WTP) values. Some people attribute this distinctive decision behavior to contrasts in the overall policy outcome expectations (preference heterogeneity) and/or differences in reactions to the changes in the environmental attributes (response heterogeneity). Others attribute this to differences in individual choice rationales, personalities, encounters, and past and present experiences. In other words, regardless of the possibility that outcomes are the same, people do not have the same emotions, convictions, disposition, or motivations. </p><p> In three separate essays, I investigate the possible reasons for the observed differences in citizens' environmental conservation policy choices and examine how preference and response heterogeneity arise. In the first essay, I ask if a priori environmental damage perception is a source of heterogeneity affecting conservation option choice decisions. In the second, I investigate if social networks (interactions among decision-making agents) affect choice decisions. In the third, I investigate if preferences change when decision making agents are allowed to deliberate among peers. </p><p> For the first essay, I conducted an on-line choice experiment (CE) survey. The survey asked questions that help to measure citizen preference for protecting environmental public goods, ascertain the value local residents are willing-to-pay (WTP), and determine how preference heterogeneity arises. CE attributes included groundwater use (measured by share of total water use from groundwater), aquatic habitat (measured by count of spawning kokanee salmon return), natural habitat health (measured by the sensitive ecosystem area reclaimed), and rural character (measured by a decrease in urban sprawl and/or a decrease in population density in rural areas). I used a special property levy as the vehicle of payment. Random parameter logit (RP) and latent class (LC) models were estimated to capture response and preference heterogeneity. The results suggest that (1) both preference and response heterogeneities were found for the choices and all environmental attributes respectively (2) respondents who have a higher value for one environmental good will have a higher value for other environmental goods, and (3) a priori damage perception could be one of the sources of response and preference heterogeneity. </p><p> In the same survey, I included people's egocentric networks, interactions, environment related activities and perceptions to empirically evaluate whether social network effect (SNE) is a source of systematic differences in preference. I estimate consumer preferences for a hypothetical future environmental conservation management alternative described by its attributes within a Nested Logit Model: nesting broader and distinct conservation options within choices impacted by individual&rsquo;s network structure. The results show that some network centrality measures capture preference heterogeneity, and consequently the differences in WTP values in a systematic way. </p><p> Third, I compare the value estimated based on the traditional choice experiment (CE) with the results obtained using the citizen jury (CJ) approach or a group-based approach or also called the "Market Stall" in some literature. I estimate the effect of deliberation on conservation choice outcomes by removing any significant differences between the people who participated in the CJ (people who volunteered to be contacted again after deliberation treatment) and those people who did the survey twice but did not volunteer for CJ (control group) in terms of their socioeconomic status and be able attribute the changes in preferences to deliberation treatment only. CJ approach involved two 90 minute deliberations held over two days to discuss and consider their preferences and WTP values with other household members. Results show that deliberation improves individuals' valuation process and there is observed difference in choice outcomes between the deliberation treatment and control groups. Both preference and response heterogeneity relatively vanish when people were allowed to deliberate among peers.</p>

<p> Non-parametric ANOVA tests, ordination, and Bayesian generalized linear models (GLMs) revealed strong physical, chemical, and biological differences among the study sites. Lower trophic foodweb indexes (<i>i.e.</i>, chlorophyll-a (chl-a) concentration, zooplankton biomass, and planktivorous fish abundance) were investigated in association with environmental variables in three terminal sloughs within the upper San Francisco Estuary. Non-metric multidimensional scaling (NMDS) showed tight clustering of data from each site. Kruskal-Wallis tests confirmed the NMDS by identifying statistically-significant differences among sites and between paired sites within each of the three regions (<i>i.e.</i>, Cache Slough, Lindsey Slough, Suisun Marsh). Bayesian GLMs identified temperature and dissolved inorganic nitrogen as primary correlates with chl-a concentration, and temperature and chl-a concentration as primary correlates with zooplankton biomass. Planktivorous fish data were insufficient to fit a GLM. Up-slough sites in Cache Slough and Suisun Marsh consistently showed greater abundances of chl-a and zooplankton relative to down-slough sites in each region. However, that pattern was reversed in Lindsey Slough. Possible reasons for this discrepancy include adjacent land-use and management practices, relative importance of alternate foodweb pathways, and the presence of a major water diversion. This study emphasizes the importance of site-specific foodweb dynamics and local anthropogenic effects, particularly in relation to design of tidal wetland restoration projects.</p><p>

<p> Impacts to wetlands protected under Clean Water Act Sections 401 and 404, can require mitigation with the goal of no net loss of acreage and function. Several studies of compensatory mitigation concluded this goal has not been met, resulting in cumulative losses. Many of these studies were completed by permit review or post-mitigation field survey. However, few studies evaluated condition before and after impact and mitigation activities as a comparison of losses and gains to assess net loss of wetlands.</p><p> Ambrose et al. (2007) evaluated both compliance and wetland condition for CWA &sect;401 mitigation projects throughout California. As a continuance of the studies of Ambrose et al. (2007), this thesis evaluated the change in condition as a result of impact and mitigation activities to address whether no net loss was achieved. A rapid assessment methodology was adapted to evaluate wetland condition using aerial photographs.</p><p> As hypothesized, impact activities decreased the wetland condition at the majority of sites. However, mitigation activities often did not increase condition. Therefore, no net loss was not achieved for most projects. Furthermore, this study illustrates the pitfalls in an evaluation of no net loss based solely on the mitigation site condition after the project implementation. The observed wetland condition may have been present at the site prior to mitigation activities. This is a misleading assumption in the assessment of gains from the project. Therefore, the change in wetland condition should be assessed through an initial evaluation of site conditions, as well as part of on-going monitoring.</p><p>

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Habitat loss is the leading cause of species extinction. Protecting and managing habitat quality is vital to an organism’s persistence, and essential to endangered species recovery. We conducted an investigation of habitat quality and potential impacts from climate change to piping plovers (Charadrius melodius) breeding on the barrier island ecosystem of New York, during 2003-2005. Our first step in this analysis was to examined the relationship between two common measures of habitat quality: density and productivity (Chapter 1). We used both central and limiting tendency data analysis to find that density significantly limited productivity across many spatial scales, especially broader scales. Our analysis of plover habitat quality (Chapter 2) focused on (1) identifying the spatial scaling of plovers to their environment; (2) determining the relative importance of four aspects of the environment (land cover, predation, management, and disturbance); and (3) determining the key environmental variables that influence productivity. We found that plover habitat selection occurred within a narrow range of spatial scales that was unique to each environmental variable. Further, we found that management and predation variables influenced population-level productivity relatively more than land cover and disturbance. Environmental variables with a significant positive influence on habitat quality were land management units, plover conservation educational signs, and symbolic string fencing erected around plover nesting areas. We found a significant negative relationship among density of people on ocean beaches, herring gull density, and land cover degradation. To quantify possible impact to plover habitat from future climate change (Chapter 3), we examined the extent of habitat change resulting from different estimates of sea-level rise (SLR) and storminess over the next 100 years. We found that the particular SLR estimate, habitat response, and storm type used to model climate changes influenced the amount of potential habitat available. Importantly, we observed synergy between SLR and storms resulting in the increasing impact of SLR and storms on plover habitat over the next 100 years. Finally, we found that coastal development contributed considerably to habitat loss when combined with climate changes. Our findings raise concerns regarding current plover recovery goals and management strategies. Density-dependent productivity may threaten the goal of a joint increase in both plover population and productivity. We advocate density monitoring and allocation of alternative nesting areas to provide the relief of possible high-density limitations. Based on our analysis of habitat selection and climate change threats, we call for a shift in management focus away from known breeding areas, towards ecosystem processes. Long-term conservation of piping plover habitat quality is more likely through protecting and promoting natural barrier island dynamics (i.e. overwash and migration) and minimizing human development on the barrier islands of New York State.

The Thung Yai Naresuan (East) Wildlife sanctuary (TYNE) is clarified as the Tiger Conservation Landscape of Global Priority and also a stronghold for other endangered and threaten species. Although, UNESCO designated this area, the cores of the Western Forest Complex (WEFCOM), as a Natural World Heritage Site in 1991, this wildlife has been threatened by habitat alteration, prey depletion, and direct killing. Yet, the information on impact of human activities and wildlife status that is needed to guild forest authorities to develop conservation strategies remains challenging. The goal of this dissertation was to increase understanding of tiger, other main predators, prey status, and also impact of human activities in the sanctuary. In the TYNE, the globally endangered species were observed including Asiatic Elephant (Elephas maximus), Tiger (Panthera tigris), Malayan Tapir (Tapirus indicus), Dhole (Cuon alpines), and Malayan Pangolin (Manis javanica). Spatially explicit capture-recapture approach estimated tiger density at 1.4-1.6 tigers/100 km2 and leopard density at 0.7-0.8 leopards/100 km2, which indicates that there might be 27±10 tigers (95% CL range from 11-46) and around 12±4 leopards (95% CL range from 8-19) roaming in the area around 1,596 km2 in TYNE. The large predators like tigers, leopards, and dholes co-occurred in the area with the combination of both spatial and temporal partitioning due to differences in predator and prey activity and low overlap in space use correlated to their prey preferences. Prey availability, human settlement areas, and human disturbance activities are the key limiting factors for their distribution and space-use. The habitat use of tiger and leopard demonstrated that the population distribution was limited in the central to the eastern part of the TYNE, while the local people occupied the west with high disturbance activities. The activities by local people in TYNE were varied and the impacts of the disturbance were complex. Slash and burn, livestock, tree cutting, and poaching appeared to be the major influence wildlife abundance and habitat around the settlement areas. The results of this study stress the need for the further conservation and management to maintain wildlife distribution and populations in the future. Better scientific understanding of wildlife biology, ecology, and social sciences would help to deal with the conservation and management issues facing the local communities and natural resources in Thung Yai Naresuan (East) Wildlife Sanctuary.

Maintaining flows and quality of water resources is critical to support ecosystem services and consumptive needs. Understanding impacts of changes in climate and land use on ecohydrologic processes in a watershed is vital to sustaining water resources for multiple uses. This study completes a continental and regional scale assessment using statistical and simulation modeling to investigate ecohydrologic impacts within watershed systems. Watersheds across the continental United States have diverse hydrogeomorphic characters, mean temperatures, soil moistures, precipitation and evaporation patterns that influence runoff processes. Changes in climate affect runoff by impacting available soil moisture, evaporation, precipitation and vegetative patterns. A one percent increase in annual soil moisture may cause a five percent increase in runoff in watersheds across the continent. Low soil moisture and high temperatures influence runoff patterns in specific regions. Spring runoff is increased by the influence Spring soil moisture, Winter and Spring evaporation, and Winter and Spring evaporation. Spring runoff is decreased by increases in Winter and Spring temperatures and increases in the vegetation index. Winter runoff is affected by maximum vegetative index, temperature, soil moisture, evaporation and precipitation. Contributing factors to runoff are influenced by geomorphic and seasonal variations requiring strategies that are site-specific and use system-wide information. Regional scale watershed analysis investigates the influence of landscape metrics on temporal streamflow processes in multiple gauged watersheds in Massachusetts, U.S.A. Time of concentration, recession coefficient, base flow index, and peak flow are hydrologic metrics used to relate to landscape metrics derived using FRAGSTAT software. Peak flow increases with increasing perimeter-area fractal dimensions, and Contagion index and decreases as Landscape Shape Index increases. There was an increasing trend in the fractal dimension over time indicative of more complex shape of patches in watershed. Base flow index and recession coefficient fluctuated from low to high decreasing recently. This could be indicative of open space legislation, conservation efforts and reforestation within the state in the last ten years. Coastal systems provide valuable ecosystem services and are vulnerable to impacts of changes in climate and continental land use patterns. Effects of land use and climate change on runoff, suspended sediments, total nitrogen and total phosphorus are simulated for coastal watersheds around the Boston Bay ecosystem. The SWAT (Soil and Water Assessment Tool) model, a continuous-time, semi distributed, process-based model, is used to simulate the watershed ecohydrologic process affecting coastal bodies. Urbanization in watersheds increased runoff by as much as 80% from the baseline. Land use change poses a major threat to water quality impacts affecting coastal ecosystems. Total nitrogen increased average of 53.8% with conservative changes in climate and land use. Total phosphorus increased an average of 57.3% with conservative changes in land use and climate change. Climate change alone causes up to 40% increase in runoff and when combined with a 3.25% increase in urban development runoff increased an average of 114%. Coastal ecosystems are impacted by nutrient runoff from watersheds. Continued urbanization and changes in climate will increase total nitrogen, total phosphorus and suspended sediments in coastal ecosystems. Continental scale runoff is affected by soil moisture and vegetative cover. Cover crops, low tillage farm practices and natural vegetation contribute to less runoff. Developing policies that encourage protection of soil structure could minimize runoff and aid in maintaining sustainable water resources. Best Management Practices and Low impact development at the national level with continued stormwater legislation directed towards sustainable land use policy will improve water quantity and quality. Fragmentation observed in Massachusetts increases the number of urban parcels and decreases the size of forested areas. Faster runoff patterns are observed but recent land management may be changing this runoff pattern. Municipal and state zoning ordinance to preserve open space and large forest patches will restrict urban growth to specific regions of a watershed. This could improve quantities of water available to ecosystems. Increases in total nitrogen, phosphorus and suspended sediments to coastal ecosystems can be minimized with use of riparian buffers and Best Management Practices within coastal watersheds. Urbanization and climate change threatens coastal ecosystems and national policy to preserve and restrict development of coastal areas will preserve coastal ecosystem services.