Variation and trends of landscape dynamics, land surface phenology and net primary production of the Appalachian Mountains

The gradients of elevations and latitudes in the Appalachian Mountains provide a unique regional perspective on landscape variations in the eastern United States and southeastern Canada. We reveal patterns and trends of landscape dynamics, land surface phenology, and ecosystem production along the Appalachian Mountains using time series data from Global Inventory Modeling and Mapping Studies and Advanced Very High Resolution Radiometer Global Production Efficiency Model datasets. We analyze the spatial and temporal patterns of the normalized difference vegetation index (NDVI), length of growing season (LOS), and net primary production (NPP) of selected ecoregions along the Appalachian Mountains regions. We compare the results in different spatial contexts, including North America and the Appalachian Trail corridor area. To reveal latitudinal variations, we analyze data and compare the results between the 30°-to-40°N and the 40°-to-50°N latitudes. The result reveal significant decreases in annual peak NDVI in the Appalachian Mountains regions. The trend for the Appalachian Mountains regions was a −0.0018 (R2=0.55, P\u3c0.0001) NDVI unit decrease per year during 25 years from 1982 to 2006. The LOS was prolonged by 0.3  days per year−1 during the 25-year percent. The NPP increased by 2.68  g Cm−2 yr−2 from 1981 to 2000

Remote Detection of Disturbance from Motorized Vehicle Use in Appalachian Wetlands

Wetland disturbance from motorized vehicle use is a growing concern across the Appalachian coalfields of southwestern Virginia and portions of adjacent states, particularly as both extractive industries and outdoor recreation development expand in regional communities. However, few attempts have been made in this region or elsewhere to adapt approaches that can assist researchers and land managers in remotely identifying and monitoring wetland habitats disturbed by motorized vehicle use. A comparative analysis of wetlands impacted and unimpacted by off-road vehicle activity at a public recreation area in Tazewell County, Virginia was conducted to determine if and how a common, satellite-derived index of vegetation health, normalized difference vegetation index (NDVI), can remotely detect wetland disturbance. NDVI values were consistently lower in wetlands impacted by several years of off-road vehicle use when compared to adjacent, unimpacted sites, with statistically-significant NDVI coldspots growing in size in impacted wetlands across the same time period. While considerations exist related to the resolution of data sources and the identification of specific modes of disturbance, NDVI and associated spatial analysis tools may provide a simple and cost-effective way for researchers and land managers to remotely monitor rates of wetland disturbance across mountainous portions of the eastern United States

Remote Sensing Applications in Monitoring of Protected Areas

Protected areas (PAs) have been established worldwide for achieving long-term goals in the conservation of nature with the associated ecosystem services and cultural values. Globally, 15% of the world’s terrestrial lands and inland waters, excluding Antarctica, are designated as PAs. About 4.12% of the global ocean and 10.2% of coastal and marine areas under national jurisdiction are set as marine protected areas (MPAs). Protected lands and waters serve as the fundamental building blocks of virtually all national and international conservation strategies, supported by governments and international institutions. Some of the PAs are the only places that contain undisturbed landscape, seascape and ecosystems on the planet Earth. With intensified impacts from climate and environmental change, PAs have become more important to serve as indicators of ecosystem status and functions. Earth’s remaining wilderness areas are becoming increasingly important buffers against changing conditions. The development of remote sensing platforms and sensors and the improvement in science and technology provide crucial support for the monitoring and management of PAs across the world. In this editorial paper, we reviewed research developments using state-of-the-art remote sensing technologies, discussed the challenges of remote sensing applications in the inventory, monitoring, management and governance of PAs and summarized the highlights of the articles published in this Special Issue

Discussing Changes in Historical Human–Environmental Dynamics Through Ecosystem Services Interactions and Future Scenarios in a Rural-Mining Region of Central Appalachians

The aim of this dissertation was to investigate how recent processes of land-change induced by humans contributed to the shaping and alteration of the current landscape in a headwater system of Central Appalachians in West Virginia (US), to understand the interactions and tradeoffs among ecosystems services and address potential solutions for targeting more sustainable human-environment interactions in a region that is deeply grounded on extractive economies. The multitiered objective was addressed through different research phases in order to unfold and disentangle a series of complex problems that the study area presents. Three main phases were used; they corresponded to distinct chapters within this study. The first paper analyzed land-cover transitions, from 1976 to 2016, using Multi-Level Intensity Analysis and Difference Components methods. Two land cover classifications were derived explicitly for this study using remote sensing methods and obtained with segmentation analysis and machine learning algorithms from historical high-resolution aerial images (1-2 meters) and ancillary data. Results allowed the author to distinguish between surface mining areas produced before and after the enactment of the Surface Mining Control and Reclamation Act (SMCRA, 1977), discuss differences among distinct socio-technical phases, and differentiate the main drivers and outcomes of landscape change processes in the area. The historical information and knowledge gained in the first step were used to inform the second chapter, whose objective was to analyze the interactions among ecosystem services and derive their bundles. Ecosystem services models were obtained using InVEST, and a custom model was explicitly defined to link water quality changes to freshwater ecosystem services. The results identified significant losses of carbon sequestration, habitat quality, and freshwater ecosystem services in areas subjected to Mountaintop Removal mining. The findings spatially located different ecosystem services bundles characterized by distinct human-environment relationships and complex anthropogenic drivers not limited to coal mining processes. The study identified the appropriate spatial scale for targeting specific management actions and implementing conservation, as well as development-restoration strategies, in areas characterized by similar social-ecological processes and deeply altered ecosystems. In the third essay, the identification of ecosystem services bundles allowed the author to delineate two distinct social-ecological systems characterized by surface coal extraction and reclamation processes produced during different historical phases. These areas were discussed as separate case studies within a time interval of seventy years, from the recent past (1976) to future scenarios (2045). The scenarios were based on a backcasting approach integrated by ecosystem services models and the analysis of functional changes within the two social-ecological units analyzed. The results highlighted differences in the flow of ecosystem services due to the intensity of mining and the different and incremental reclamation approaches used in the scenarios. The comparison of threats and opportunities within each scenario, identified, in the discussion section, a range of plausible hypotheses and solutions the stakeholders and communities of the region should face if they want to rehabilitate the social and ecological conditions to promote a more sustainable approach for the future of these places

Landscape Ecology of Birds on Mount Leconte, Great Smoky Mountains National Park

Landbirds form a significant component of wildlife resources in the Great Smoky Mountains National Park. The present study explored how forest structure and composition of deciduous-coniferous ecotones influenced diversity, richness, and relative abundance of bird species and how bird species responded to the spruce-fir community. Using a form of the variable-circular plot method, I conducted audio-visual censuses of diurnal birds on Mount LeConte. I established 212 geo-referenced census points on six trails, which were used as gradient-oriented transects (gradsects). I measured habitat characteristics at the same census points. I used forest community types for each point on gradsects to delineate boundaries. I applied The Tasseled-Cap (T-CAP) , a graphic description of the spectral-temporal development of locations, to analyze bird-habitat relationships in order to investigate the utility of Landsat T-CAP indices in predicting forest patterns and bird species\u27 richness and abundance. I derived elevation, slope, and aspect from differentially corrected GPS coordinates using ArcView Spatial Analyst and T-Cap indices from Landsat TM remotely sensed data for forest community types and each vegetation sampling station using Earth Resources Data Analysis System. My results showed correlations among the abundances of many bird species and elevational, floristic, and physiogonomic features of their habitat, both for univariate and multivariate characters. Both cover type and size class (dbh) were important to the breeding avifauna; various groups of breeding birds were associated with either one or both variables. Ecotones along the gradsects among forest types were perceived by many bird species as significant discontinuities. Zones of both rapid and gradual change in bird abundance were observed. For certain bird species, patterns of bird distribution and forest types coincided. Individual species responded to patchiness, vegetation structure, and elevation, sometimes in a predictable manner. I observed clusters of species and communities along my derived zones that appeared to be different. Species expanded or contracted their distributions in localities where the homogenous ecotone was displaced upward or downward in elevation relative to the location of the ecotone on Mount LeConte. Spatial fluctuations were, in general, related to zonal transitions in forest types. T-CAP indices were related to species\u27 responses to changes in landscape structure and composition. Distinct patterns in vegetation that corresponded with different forest types and zones of rapid and gradual change in bird abundance were observed. Greenness and wetness values differentiated closed canopy fir stands from all other classes

The economic costs and ecological benefits of protected areas for biodiversity conservation

Conservation science acknowledges that economic cost and ecological benefit information is important for effective biodiversity conservation decision making. Obtaining this information for protected areas has proven difficult, however. This dissertation explores various aspects of obtaining information on the costs and benefits of protected areas in an effort to support applied conservation. Here I present a set of studies that 1) examine the threat and cost of plant invasion on protected areas, both for cumulative invasion and 2) across species that differ in their management priority, 3) provide a method for measuring the benefit of forest conservation, and 4) describe the conservation benefit implications from multiple conservation organizations working in the same region. The first two studies show that while conservation needs and prior costs can be estimated, there is no evidence that past expenditures relate to future budget requirements. This result is the impetus for the next study, where I develop a method to estimate the conservation benefit of forest protection using satellite imagery so that conservation professionals can better assess the relationship between conservation actions and outcomes. The final study reveals that competition for limited funding affects how conservation organizations allocate their resources, resulting in variation in benefit that depends on the organizations\u27 priority alignment. Overall, my dissertation reinforces the importance of properly accounting for costs and benefits in conservation planning and provides insight and tools to help achieve that outcome

SPATIAL AND TEMPORAL PATTERNS OF INVASIVE EXOTIC PLANT SPECIES IN RESPONSE TO TIMBER HARVESTING IN A MIXED MESOPHYTIC FOREST OF EASTERN KENTUCKY

Invasive exotic species (IES) responses to silvicultural treatments eight years after timber harvesting were examined and compared to one-year post-harvest IES survey in University of Kentucky’s Robinson Forest. The temporal effects of harvesting were further compared between harvested and non-harvested watersheds. Analyses were performed to identify IES spatial distribution and determine the relationships between IES presence and disturbance effects, biological, and environmental characteristics. IES prevalence was higher in the harvested watersheds and was influenced by canopy cover, shrub cover and disturbance proximity. Ailanthus altissima and Microstegium vimineum presence in the study area has decreased over time. Comparing to the 1-yr post-harvest study which only identified direct harvesting effects (e.g. canopy cover and disturbance proximities) as significant predictors, the 8-yr post-harvest survey results suggest that while harvesting effects and disturbance proximity still play an important role, environmental characteristics have also taken precedence in predicting IES presence. Overall IES prevalence has decreased but invasive plant species richness has increased over time. Results indicate that IES eradication may not need to be conducted immediately after harvesting, and when needed, can primarily target IES hotspots where low canopy cover, proximity to disturbance, and southwest facing slopes convene on the landscape

Master\u27s Project: Describing Forest Structure in Southern Blue Ridge Cove Forests: A LiDAR-Based Analysis

The practice of ecological restoration requires identifying a reference, or desired condition. In the Eastern United States, reference conditions can be difficult to identify due to the widespread impacts of anthropogenic influences like logging, fire suppression, and forest fragmentation on ecosystem structure. The Southern Appalachian Mountains contain some of the largest patches of unlogged primary forests in the Eastern United States. Although not entirely unaltered by humans, these existing primary forests can provide important information about the composition and structure of the Southern Appalachian landscape prior to Euro-American settlement. Cove forests occupy mid-elevation slopes throughout the Southern Appalachians. Due to their sheltered topography, mesic nature, and low fire return interval, existing primary cove forests can serve as an appropriate community-specific reference condition. This project uses Light Detection and Ranging (LiDAR)-derived canopy height models to predict old growth forest stand characteristics in Southern Appalachian cove forests. By using grey-level co-occurrence texture analyses in primary forests throughout Pisgah and Nantahala National Forests, and Great Smoky Mountains National Park, the project introduces a new LiDAR-based methodology for describing ecosystem structure in forest landscapes. This methodology provides insight into the canopy structure of old growth cove forests, which may be useful for both ecological restoration and forest management in this forest community

Canopy gap characteristics, their size-distribution and spatial pattern in a mountainous cool temperate forest of Japan

Canopy gaps and their characteristic features (e.g. area and shape) influence the availability of nutrients, moisture and light in a forest ecosystem, and consequently affect the regeneration process and species composition in the forest. Most of the earlier research on canopy gap used field measurement and conventional remote sensing to quantify gap and these methods have limitations and accuracy problems. However, the development in Light Detecting and Ranging (LiDAR) technology has been effective in overcoming limitations and challenges associated with conventional remote sensing. The ability of LiDAR to represent the three-dimensional structure of the canopies and the sub-canopy resulting in high-resolution topographic maps, highly accurate estimated of vegetation height, cover and canopy structure makes it suitable technology for gap studies. LiDAR-based digital surface model (DSM) and digital elevation model (DEM) were used to quantify the canopy gaps over 5124ha of University of Tokyo Chichibu Forests (UTCF) consisting of three forest-types; primary, secondary and plantation forest. Disturbance driven canopy gaps might have spatial and characteristic variation due to differences in disturbance history, nature, frequency and intensity in different forest and land-types. Quantifying gap characteristics and studying variation and size distribution in different forest types and topography help to understand the different gap dynamics and their ecological perspectives. In this study, a gap was defined as an opening with a maximum height of 2m and minimum area threshold of 10m2. The minimum area threshold, which represents the gap area created by the death of at least a single tree, was determined through a random sampling of 100 tree crowns at UTCF using high resolution aerial photographs. Gap size distribution was analyzed in different forest types and land types. Spatial autocorrelation of gap occurrence was studied using semivariance analysis and distance to the nearest gap (DNG), which is the distance to the nearest gap for an individual gap. Canopy gap size frequency distribution in different forest-types was investigated using power-law. The negative exponent (α), which is also the scaling component of the power-law distribution, was compared between forest-types. Altogether, 6179 gaps with area 10-11603 m2 were found. Gap size distribution in UTCF showed skewness with a high frequency of smaller gaps and a few large gaps. Half of the gaps were smaller than 19 m2 and less than one percent of gaps (0.73 %) were larger than 400 m2. Primary forest contained high gap density (1.85 gaps per ha), shortest mean-DNG (22m) and second-largest gap-area fraction (0.72 %) after plantation forest area (0.76 %). Secondary forest had the lowest gap density (1.03 gaps per hectare) but had the larger mean gap-area (43 m2) than in primary forest (39 m2). The Kolmogorov–Smirnov test showed differences (p2400 m2) were absent in the secondary forest. Gap size frequency distribution followed a power-law distribution only in plantation forest area (p>0.1, α =2.27). The scaling parameter in the primary and secondary forest was 2.56 (p=0.01) and 2.20 (p=0.02), respectively. Gap distribution showed some spatial autocorrelation in primary and secondary forest at least with distance up to 1300m. Most of the gaps in the primary forest were concentrated in the valley and middle slope, whereas the upper and middle slope had fewest gaps