Scholars@Duke
Dean L. Urban

Dean L. Urban

Professor Emeritus of Environmental Sciences and Policy
Environmental Sciences and Policy
deanu@duke.edu
Box 90328, Durham, NC 27708-0328
A320 Lev Sci Res Ctr, Durham, NC 27708

Selected Publications

Landscape Ecology: A Task-Oriented Perspective

Book · January 1, 2024 This is methods/tools textbook that covers the fundamental tasks in research and management at the landscape scale. It brings together tools from a range of disciplines and presents them in a natural workflow that a practitioner can appreciate. Alternative ... Full text Cite

The Contribution of Microrefugia to Landscape Thermal Inertia for Climate-Adaptive Conservation Strategies

Journal Article Earth's Future · June 1, 2023 Current temperatures in microrefugia may persist longer than in nearby areas as temperatures warm. However, locating and measuring the contribution of microrefugia to thermal inertia in a landscape is challenging. We measured the thermal buffering capacity ... Full text Cite

Agents and Implications of Landscape Pattern: Working Models for Landscape Ecology

Book · January 1, 2023 Featured Publication This is an ecology textbook focused on key principles that underpin research and management at the landscape scale. It covers (1) agents of pattern (the physical template, biotic processes, and disturbance regimes); (2) scale and pattern (why scale matters ... Full text Cite

The Nonpoint Sources and Transport of Baseflow Nitrogen Loading Across a Developed Rural-Urban Gradient

Journal Article Water Resources Research · July 1, 2022 Nonpoint source urban nutrient loading into streams and receiving water bodies is widely recognized as a major environmental management challenge. A dominant research and management paradigm assumes that loading primarily derives from elevated stormwater. ... Full text Cite

Characterizing and classifying urban watersheds with compositional and structural attributes

Journal Article Hydrological Processes · September 1, 2021 Current land-use classifications used to assess urbanization effects on stream water quality date back to the 1980s when limited information was available to characterize watershed attributes that mediate non-point source pollution. With high resolution re ... Full text Cite

Improved connectivity analysis using multiple low-cost paths to evaluate habitat for the endangered San Martin titi monkey (Plecturocebus oenanthe) in north-central Peru

Journal Article Landscape Ecology · August 1, 2019 Context: Graph-theoretic evaluations of habitat connectivity often rely upon least-cost path analyses to evaluate connectedness of habitat patches, based on an underlying cost surface. We present two improvements upon these methods. Objectives: As a case s ... Full text Cite

Watershed urban development controls on urban streamwater chemistry variability

Journal Article Biogeochemistry. · June 2019 Featured Publication Watershed urbanization increases the concentrations of major ions in downstream freshwater ecosystems. Non-point source ions from human activities and the chemical weathering of infrastructure are efficiently transported by stormwater runoff through subsur ... Full text Cite

Scoured or suffocated: Urban stream ecosystems oscillate between hydrologic and dissolved oxygen extremes

Journal Article Limnology and Oceanography · May 1, 2019 Featured Publication Headwater streams draining urbanized watersheds are subject to frequent and intense storm flows. These floods can disrupt metabolic processes occurring in benthic biofilms via the removal of biomass (i.e., scouring flows, bed mobilization) or light attenua ... Full text Cite

Hurricane disturbances, tree diversity, and succession in North Carolina Piedmont forests, USA

Journal Article Journal of Forestry Research · February 15, 2019 Windthrow plays a critical role in maintaining species diversity in temperate forests. Do large-scale strong wind events (i.e., tropical cyclones, including hurricanes, typhoons and severe cyclonic storms) increase tree diversity in severely damaged forest ... Full text Cite

Leveraging Big Data Towards Functionally-Based, Catchment Scale Restoration Prioritization.

Journal Article Environmental management · December 2018 The persistence of freshwater degradation has necessitated the growth of an expansive stream and wetland restoration industry, yet restoration prioritization at broad spatial extents is still limited and ad-hoc restoration prevails. The River Basin Restora ... Full text Cite

Testing the effects of four urbanization filters on forest plant taxonomic, functional, and phylogenetic diversity.

Journal Article Ecological applications : a publication of the Ecological Society of America · December 2018 Featured Publication Ongoing urban development has significant effects on ecosystems, including changes to land cover, environmental conditions, and species' distributions. These various impacts may have opposing or interacting effects on plant communities, making it difficult ... Full text Cite

Not all pavements lead to streams: Variation in impervious surface connectivity affects urban stream ecosystems

Journal Article Freshwater Science · September 1, 2018 Watershed urbanization leads to chemical and thermal pollution of urban streams and significant declines in aquatic biodiversity. Most investigators have focused on variation in total watershed impervious surface cover (ISC) as the primary driver of urban ... Full text Cite

Pulling apart the urbanization axis: patterns of physiochemical degradation and biological response across stream ecosystems

Journal Article Freshwater Science · September 1, 2018 Watershed urbanization introduces a variety of physical, chemical, and thermal stressors to receiving streams and leads to well-documented declines in the diversity of fish and macroinvertebrates. Far less knowledge is available about how these urban stres ... Full text Cite

Nativity and seed dispersal mode influence species’ responses to habitat connectivity and urban environments

Journal Article Global Ecology and Biogeography · September 1, 2018 Aim: Urbanization alters local environmental conditions and the ability of species to disperse between remnant habitat patches within the urban matrix. Nonetheless, despite the ongoing growth of urban areas worldwide, few studies have investigated the rela ... Full text Cite

Comparing methods for detecting multilocus adaptation with multivariate genotype-environment associations.

Journal Article Molecular ecology · May 2018 Featured Publication Identifying adaptive loci can provide insight into the mechanisms underlying local adaptation. Genotype-environment association (GEA) methods, which identify these loci based on correlations between genetic and environmental data, are particularly promisin ... Full text Cite

Evidence-Based Causal Chains for Linking Health, Development, and Conservation Actions.

Journal Article Bioscience · March 2018 Featured Publication Sustainability challenges for nature and people are complex and interconnected, such that effective solutions require approaches and a common theory of change that bridge disparate disciplines and sectors. Causal chains offer promising approaches to achiev ... Full text Open Access Cite

Benefit relevant indicators: Ecosystem services measures that link ecological and social outcomes

Journal Article Ecological Indicators · February 1, 2018 Featured Publication There is a growing movement in government, environmental non-governmental organizations and the private sector to include ecosystem services in decision making. Adding ecosystem services into assessments implies measuring how much a change in ecological co ... Full text Cite

Modeling plant composition as community continua in a forest landscape with LiDAR and hyperspectral remote sensing.

Journal Article Ecological applications : a publication of the Ecological Society of America · January 2018 Featured Publication In light of the need to operationalize the mapping of forest composition at landscape scales, this study uses multi-scale nested vegetation sampling in conjunction with LiDAR-hyperspectral remotely sensed data from the G-LiHT airborne sensor to map vascula ... Full text Cite

Data and Modeling Infrastructure for National Integration of Ecosystem Services into Decision Making: Expert Summaries

Report · July 17, 2017 Resource managers face increasingly complex decisions as they attempt to manage for the long-term sustainability and the health of natural resources. Incorporating ecosystem services into decision processes provides a means for increasing public engagement ... Open Access Link to item Cite

Mapping Conservation Strategies under a Changing Climate.

Journal Article Bioscience · June 2017 Featured Publication Full text Open Access Cite

An assessment of high carbon stock and high conservation value approaches to sustainable oil palm cultivation in Gabon

Journal Article Environmental Research Letters · January 1, 2017 Industrial-scale oil palm cultivation is rapidly expanding in Gabon, where it has the potential to drive economic growth, but also threatens forest, biodiversity and carbon resources. The Gabonese government is promoting an ambitious agricultural expansion ... Full text Open Access Cite

Proposal for Increasing Consistency When Incorporating Ecosystem Services into Decision Making

Report · November 15, 2016 In October 2015, the U.S. Executive Offices of the President—the Office of Management and Budget, the Council on Environmental Quality, and the Office of Science and Technology Policy—released a memo, “Incorporating Ecosystem Services into Federal Decision ... Open Access Link to item Cite

Vegetation dynamics vary across topographic and fire severity gradients following prescribed burning in Great Smoky Mountains National Park

Journal Article Forest Ecology and Management. · April 2016 Featured Publication Fire exclusion in the United States over the last century has had major impacts on forest ecosystems and landscapes. Out of a desire to reverse or mitigate the impacts of fire exclusion, some managers conduct prescribed fires meant to mimic the historic ec ... Full text Cite

Downstream Dissipation of Storm Flow Heat Pulses: A Case Study and its Landscape-Level Implications

Journal Article Journal of the American Water Resources Association · April 1, 2016 Featured Publication Storms in urban areas route heat and other pollutants from impervious surfaces, via drainage networks, into streams with well-described negative consequences on physical structure and biological integrity. We used heat pulses associated with urban storms a ... Full text Cite

A typology of time-scale mismatches and behavioral interventions to diagnose and solve conservation problems.

Journal Article Conservation biology. · February 2016 Featured Publication Ecological systems often operate on time scales significantly longer or shorter than the time scales typical of human decision making, which causes substantial difficulty for conservation and management in socioecological systems. For example, invasive spe ... Full text Open Access Cite

Reconciling oil palm expansion and climate change mitigation in Kalimantan, Indonesia.

Journal Article PloS one · January 2015 Our society faces the pressing challenge of increasing agricultural production while minimizing negative consequences on ecosystems and the global climate. Indonesia, which has pledged to reduce greenhouse gas (GHG) emissions from deforestation while doubl ... Full text Open Access Cite

Evaluating the effectiveness of a safe harbor program for connecting wildlife populations

Journal Article Animal Conservation · December 1, 2013 Featured Publication Conversion of lands to agriculture and development within remaining natural habitats have fragmented ecosystems and reduced wildlife populations. The US Fish and Wildlife Service has adopted an incentive-based conservation strategy known as the Safe Harbor ... Full text Cite

Long-term land cover dynamics by multi-temporal classification across the Landsat-5 record

Journal Article Remote Sensing of Environment · 2013 Featured Publication Supervised classification of land cover across space and time is a long-standing goal of the Earth Science community. Although most past and current analyses focus on detecting changes between two or more times, the opening of the USGS Landsat archive in 2 ... Full text Cite

Streams in the urban heat island: spatial and temporal variability in stream temperatures

Journal Article Freshwater Science · 2012 Featured Publication Cite

Comparing Habitat Suitability and Connectivity Modeling Methods for Conserving Pronghorn Migrations

Journal Article PLoS ONE · 2012 Featured Publication Terrestrial long-distance migrations are declining globally: in North America, nearly 75% have been lost. Yet there has been limited research comparing habitat suitability and connectivity models to identify migration corridors across increasingly fragment ... Full text Open Access Cite

Focused assessment of scale-dependent vegetation pattern

Journal Article · December 1, 2011 Ecological processes frequently occur at multiple spatial scales simultaneously. For example, fires imprint the landscape at a variety of spatial scales, from small areas of high burn intensity due to patchy surface fuels, to large stands within fires that ... Full text Cite

Community structure in pelagic marine mammals at large spatial scales as revealed by multivariate ordination

Journal Article Marine Ecology Progress Series · 2011 The understanding of a species’ niche is fundamental to the concept of ecology, yet relatively little work has been done on niches in pelagic marine mammal communities. Data collection on the distribution and abundance of marine mammals is costly, time con ... Full text Link to item Cite

Causes and implications of the correlation between forest productivity and tree mortality rates

Journal Article Ecological Monographs · January 1, 2011 At global and regional scales, tree mortality rates are positively correlated with forest net primary productivity (NPP). Yet causes of the correlation are unknown, in spite of potentially profound implications for our understanding of environmental contro ... Full text Cite

Forest bird communities across a gradient of urban development

Journal Article Urban Ecosystems · 2010 Featured Publication This study examined native bird communities in forest patches across a gradient of urbanization. We used field data and multivariate statistical techniques to examine the effects of landscape context, roads, traffic noise, and vegetation characteristics on ... Full text Cite

Graph models of habitat mosaics.

Journal Article Ecol Lett · March 2009 Featured Publication Graph theory is a body of mathematics dealing with problems of connectivity, flow, and routing in networks ranging from social groups to computer networks. Recently, network applications have erupted in many fields, and graph models are now being applied i ... Full text Link to item Cite

Tree damage risk factors associated with large, infrequent wind disturbances of Carolina forests

Journal Article Forestry · July 1, 2008 Past studies of large, infrequent wind disturbances have shown that meteorological, topographic and biological factors interact to generate complex damage patterns, but have left open the extent to which these limited past findings are representative and c ... Full text Cite

A graph-theory framework for evaluating landscape connectivity and conservation planning.

Journal Article Conserv Biol · April 2008 Featured Publication Connectivity of habitat patches is thought to be important for movement of genes, individuals, populations, and species over multiple temporal and spatial scales. We used graph theory to characterize multiple aspects of landscape connectivity in a habitat ... Full text Link to item Cite

Uncertainty in spatially explicit population models

Journal Article Biological Conservation. · April 2008 Spatially explicit population models (SEPMs) are often used in conservation planning. However, confidence intervals around predictions of spatially explicit population models can greatly underestimate model uncertainty. This is partly because some sources ... Full text Cite

Modeling population connectivity by ocean currents, a graph-theoretic approach for marine conservation

Journal Article Landscape Ecology · 2008 Featured Publication The dispersal of individuals among marine populations is of great importance to metapopulation dynamics, population persistence, and species expansion. Understanding this connectivity between distant populations is key to their effective conservation and m ... Full text Cite

Graph theory as a proxy for spatially explicit population models in conservation planning.

Journal Article Ecol Appl · September 2007 Featured Publication Spatially explicit population models (SEPMs) are often considered the best way to predict and manage species distributions in spatially heterogeneous landscapes. However, they are computationally intensive and require extensive knowledge of species' biolog ... Full text Link to item Cite

A multivariate assessment of changes in wetland habitat for waterbirds at Moosehorn National Wildlife Refuge, Maine, USA

Journal Article Wetlands · March 1, 2007 We assessed changes in vegetative structure of 49 impoundments at Moosehorn National Wildlife Refuge (MNWR), Maine, USA, between the periods 1984-1985 to 2002 with a multivariate, adaptive approach that may be useful in a variety of wetland and other habit ... Full text Cite

The ecodist package for dissimilarity-based analysis of ecological data

Journal Article Journal of Statistical Software · 2007 Featured Publication Ecologists are concerned with the relationships between species composition and environmental factors, and with spatial structure within those relationships. A dissimilarity-based framework incorporating space explicitly is an extremely flexible tool for a ... Cite

Neutral models for testing landscape hypotheses

Journal Article Landscape Ecology · January 1, 2007 Neutral landscape models were originally developed to test the hypothesis that human-induced fragmentation produces patterns distinctly different from those associated with random processes. Other uses for neutral models have become apparent, including the ... Full text Cite

Monitoring succession from space: A case study from the north Carolina Piedmont

Journal Article APPLIED VEGETATION SCIENCE · 2007 Featured Publication Full text Cite

Causes and consequences of land use change in the north carolina piedmont: the scope of uncertainty

Conference · December 1, 2006 The Triangle Landscape Change Project is an on-going effort at regional assessment centered on the Triangle region of North Carolina, a region framed by the cities of Raleigh, Durham, and Chapel Hill. Like many regions of the eastern United States and else ... Full text Cite

Edge Effects on Species Composition and Exotic Species Abundance in the North Carolina Piedmont

Journal Article Biol Invasions. · July 2006 Edges between forest and non-forest habitats often have significant effects on forest microclimate and resource availability, with corresponding effects on species composition and abundance. Exotic species are often increased in abundance near forest edges ... Full text Cite

Spatially varying rules of landscape change: Lessons from a case study

Journal Article Landscape and Urban Planning · January 1, 2006 Land-cover and land-use change modeling have become increasingly common, and myriad different modeling techniques are now available. Many techniques assume that the rules of landscape change are the same everywhere within the study area, an assumption that ... Full text Cite

Gradient analysis, the next generation: Towards more plant-relevant explanatory variables

Journal Article Canadian Journal of Forest Research · July 1, 2005 The long history of gradient analysis is anchored in the observation that species turnover can be described along elevation gradients. This model is unsatisfying in that elevation is not directly relevant to plants and the ubiquitous "elevation gradient" i ... Full text Cite

A simple method for estimating potential relative radiation (PRR) for landscape-scale vegetation analysis

Journal Article Landscape Ecology · February 1, 2005 Radiation is one of the primary influences on vegetation composition and spatial pattern. Topographic orientation is often used as a proxy for relative radiation load due to its effects on evaporative demand and local temperature. Common methods for incorp ... Full text Cite

Modeling ecological processes across scales

Journal Article Ecology · 2005 Featured Publication The issue of scaling impinges on every aspect of landscape ecology and much of ecology in general. Consequently, the topic has invited a vast commentary. One result of scaling research is so-called scaling laws that describe how observations scale (e.g., a ... Cite

Scale-specific inference using wavelets

Journal Article Ecology · 2005 Featured Publication Understanding of spatial pattern and scale has been identified as a key issue in ecology, yet ecology has traditionally lacked necessary tools for making inference about relationships between scale-specific patterns. We introduce wavelet-coefficient regres ... Cite

Modeling landscape vegetation pattern in response to historic land-use: A hypothesis-driven approach for the North Carolina Piedmont, USA

Journal Article Landscape Ecology · 2005 Featured Publication Current methods of vegetation analysis often assume species response to environmental gradients is homogeneously monotonic and unimodal. Such an approach can lead to unsatisfactory results, particularly when vegetation pattern is governed by compensatory r ... Full text Cite

Trends in twentieth-century tree growth at high elevations in the Sierra Nevada and White Mountains, USA

Journal Article Holocene · 2005 Featured Publication We analysed a multispecies tree-ring data base to assess the degree to which twentieth-century growth trends reflect tree growth of the last millennium. We examined ∼1000-yr chronologies for five species of high-elevation conifers at 13 sites in western No ... Full text Cite

Beta diversity and nature reserve system design in the Yukon, Canada

Journal Article Conservation Biology · 2005 Featured Publication Design of protected areas has focused on setting targets for representation of biodiversity, but often these targets do not include prescriptions as to how large protected areas should be or where they should be located. Principles of island biogeography t ... Full text Cite

Forest edges and tree growth rates in the north carolina piedmont

Journal Article Ecology. · August 2004 Forest fragmentation is a common process in forests worldwide, with implications for tree species composition and abundance. In particular, the effects of forest– non‐forest edges on microclimate are often profound, usually resulting in increased light ava ... Full text Cite

An empirical approach towards improved spatial estimates of soil moisture for vegetation analysis

Journal Article Landscape Ecology · July 20, 2004 Landscape-level spatial estimates of soil water content are critical to understanding ecological processes and predicting watershed response to environmental change. Because soil moisture influences are highly variable at the landscape scale, most meteorol ... Full text Cite

Using spatial analysis to assess bottlenose dolphins as an indicator of healthy fish habitat

Chapter · January 1, 2004 Florida Bay, which lies at the southern tip of the Florida peninsula (Figure 27.1), is the terminus of the largest ecosystem restoration project ever attempted in the United States. The Comprehensive Everglades Restoration Project (CERP), with the ambitiou ... Full text Cite

Spatial dependency of vegetation-environment linkages in an anthropogenically influenced wetland ecosystem

Journal Article Ecosystems · January 1, 2004 Management and restoration of vegetation patterns in ecosystems depends on an understanding of allogenic environmental factors that organize species assemblages and autogenic processes linked to assemblages. However, our ability to make strong inferences a ... Full text Cite

Strategies for ecological extrapolation

Journal Article Oikos · 2004 Featured Publication Full text Cite

Efficient flow computation on massive grid terrain datasets

Journal Article GeoInformatica · December 1, 2003 As detailed terrain data becomes available. GIS terrain applications target larger geographic areas at finer resolutions. Processing the massive datasets involved in such applications presents significant challenges to GIS systems and demands algorithms th ... Full text Cite

Spatial pattern of Quercus regeneration limitation and Acer rubrum invasion in a Piedmont forest

Journal Article Journal of vegetation science. · June 2003 Across eastern North America, there is a temporal trend from open Quercus forests to closed forests with increased Acer rubrum in the understory. We used a series of Ripley's K(d) analyses to examine changes in the spatial pattern of Quercus and Acer rubru ... Full text Cite

Extending community ecology to landscapes

Journal Article Ecoscience · 2002 Featured Publication A goal of landscape ecology is to infer processes or constraints that generate spatial pattern in communities and ecosystems. The rich tradition of plant community ecology is now being extended to address spatial pattern in vegetation over large spatial ex ... Cite

Focal species, community representation, and physical proxies as conservation strategies: A case study in the Amphibolite Mountains, North Carolina, U.S.A.

Journal Article Conservation Biology · 2002 Featured Publication Conservation organizations are increasingly employing representative-based conservation strategies to overcome the limits of a species-by-species approach and to expand the focus of conservation to include overall biodiversity and ecosystem processes. To c ... Full text Cite

Environmental correlates of oak decline and red maple increase in the North Carolina Piedmont

Journal Article Castanea · January 1, 2002 We examine the decline of oaks (Quercus spp.) in eastern forests and the concomitant increase in red maple (Acer rubrum) abundance using data collected over 75 years near Durham, North Carolina. Oaks declined in abundance on all hardwood-dominated sites, w ... Cite

Estimating parameters of forest patch transition models from gap models

Journal Article Environmental Modelling and Software · October 10, 2001 An algorithm to estimate the parameter values of a transition forest landscape model (MOSAIC) from a gap model (FACET) is presented here. MOSAIC is semi-Markov; it includes random distributed holding times and fixed or deterministic delays in addition to t ... Full text Cite

Landscape connectivity: A graph-theoretic perspective

Journal Article Ecology · 2001 Featured Publication Ecologists are familiar with two data structures commonly used to represent landscapes. Vector-based maps delineate land cover types as polygons, while raster lattices represent the landscape as a grid. Here we adopt a third lattice data structure, the gra ... Cite

Flow computation on massive grids

Journal Article Proceedings of the ACM Workshop on Advances in Geographic Information Systems · January 1, 2001 As detailed terrain data becomes available, GIS applications target larger geographic areas at finer resolutions. Processing the massive data presents significant challenges to GIS systems and demands algorithms that are optimized for both data movement an ... Full text Cite

Modeling forest landscapes: Parameter estimation from gap models over heterogeneous terrain

Journal Article Simulation · January 1, 2001 Parameter values of a forest landscape model (MOSAIC) are estimated from a terrain sensitive gap model (FACET) over a large number of terrain types. MOSAIC is a semi-Markov model with states defined by cover types. For each terrain type, gap-model output i ... Full text Cite

Forest gradient response in Sierran landscapes: The physical template

Journal Article Landscape Ecology · 2000 Featured Publication Vegetation pattern on landscapes is the manifestation of physical gradients, biotic response to these gradients, and disturbances. Here we focus on the physical template as it governs the distribution of mixed-conifer forests in California's Sierra Nevada. ... Full text Cite

Forest pattern in Sierran landscapes: the physical template

Journal Article Landscape Ecology · 2000 Cite

Using model analysis to design monitoring programs for landscape management and impact assessment

Journal Article Ecological Applications · 2000 Featured Publication While ecologists have long recognized the key role of monitoring programs in natural-resource management, we have only recently come to appreciate the logistical difficulties of designing powerful yet efficient schemes for monitoring large, heterogeneous l ... Cite

Landscape connectivity: A conservation application of graph theory

Journal Article Journal of Environmental Management · 2000 Featured Publication We use focal-species analysis to apply a graph-theoretic approach to landscape connectivity in the Coastal Plain of North Carolina. In doing so we demonstrate the utility of a mathematical graph as an ecological construct with respect to habitat connectivi ... Full text Cite

Modeling the effects of fire management alternatives on Sierra Nevada mixed-conifer forests

Journal Article Ecological Applications · January 1, 2000 Decades of fire exclusion have led to hazardous fuel accumulations and the deterioration of fire-dependent ecosystems, particularly in the American West. Managers are striving to return the ecological role of fire to many ecosystems and would benefit from ... Full text Cite

Connectivity of forest fuels and surface fire regimes

Journal Article Landscape Ecology · January 1, 2000 The connectivity of a landscape can influence the dynamics of disturbances such as fire. In fire-adapted ecosystems, fire suppression may increase the connectivity of fuels and could result in qualitatively different fire patterns and behavior. We used a s ... Full text Cite

Spatial components of bowhead whale (Balaena mysticetus) distribution in the Alaskan Beaufort Sea

Journal Article Canadian Journal of Fisheries and Aquatic Sciences · January 1, 2000 Bowhead whales (Balaena mysticetus) on their fall migration are exposed to oil exploration activities in the Alaskan Beaufort Sea. While previous research into the effect of industrial noise on whale behavior and distribution has noted significant response ... Full text Cite

Forest pattern, fire, and climatic change in the Sierra Nevada

Journal Article Ecosystems · 1999 Featured Publication In the Sierra Nevada, distributions of forest tree species are largely controlled by the soil-moisture balance. Changes in temperature or precipitation as a result of increased greenhouse gas concentrations could lead to changes in species distributions. I ... Full text Cite

Interactions between forest heterogeneity and surface fire regimes in the southern Sierra Nevada

Journal Article Canadian Journal of Forest Research · January 1, 1999 Fire is a major agent of spatial pattern formation in forests, as it creates a mosaic of burned and unburned patches. While most research has focused on landscape-level patterns created by crown fires, millions of hectares of forests in North America are s ... Full text Cite

A model of surface fire, climate and forest pattern in the Sierra Nevada, California

Journal Article Ecological Modelling · 1999 Featured Publication A spatially explicit forest gap model was developed for the Sierra Nevada, California, and is the first of its kind because it integrates climate, fire and forest pattern. The model simulates a forest stand as a grid of 15 x 15 m forest plots and simulates ... Full text Cite

Avian response to landscape pattern: the role of species' life histories

Journal Article NCASI Technical Bulletin · January 1, 1999 An account is given on initial tests relevant to the hypotheses that life histories of species within communities may differ among geographic locations and that communities from distinct biomes may respond uniquely to a given trajectory of landscape change ... Cite

Interactions between forest heterogeneity and surface fire regimes in the southern Sierra Nevada (vol 29, pg 202, 1999)

Journal Article CANADIAN JOURNAL OF FOREST RESEARCH-REVUE CANADIENNE DE RECHERCHE FORESTIERE · 1999 Featured Publication Cite

Detecting critical scales in fragmented landscapes

Journal Article Ecology and Society · 1997 Featured Publication We develop methods for quantifying habitat connectivity at multiple scales and assigning conservation priority to habitat patches based on their contribution to connectivity. By representing the habitat mosaic as a mathematical "graph," we show that percol ... Cite

Detecting critical scales in fragmented landscapes

Journal Article Conservation Ecology · 1997 We develop methods for quantifying habitat connectivity at multiple scales and assigning conservation priority to habitat patches based on their contribution to connectivity. By representing the habitat mosaic as a mathematical "graph," we show that percol ... Cite

Models of forest dynamics based on roles of tree species

Journal Article Ecological Modelling · January 1, 1996 A linkage between the two major modeling approaches to forest dynamics, transition Markovian models and JABOWA-FORET type simulators, is generated by developing a compact model of forest dynamics. This patch transition model utilizes functional roles inste ... Full text Cite

Coupling a spatially-explicit forest gap model with a 3-D solar routine to simulate latitudinal effects

Journal Article Ecological Modelling · January 1, 1996 A multi-scaled forest model (ZELIG) which spatially embeds patch-scale processes into a larger landscape was linked with a 3-D insolation routine to simulate the effects of latitudinal variation in solar radiation on the growth and spatial patterns of idea ... Full text Cite

Transition and gap models of forest dynamics

Journal Article Ecological Applications · January 1, 1995 Full text Cite

Potential response of pacific northwestern forests to climatic change, effects of stand age and initial composition

Journal Article Climatic Change · March 1, 1993 We used an individual-based forest simulator (a gap model) to assess the potential effects of anthropogenic climatic change on conifer forests of the Pacific Northwestern United States. Steady-state simulations suggested that forest zones could be shifted ... Full text Cite

Forest ecosystem dynamics: linking forest succession, soil process and radiation models

Journal Article Ecological Modelling · January 1, 1993 The Forest Ecosystem Dynamics (FED) project involves the development of an integrated mathematical model which links individual submodels of soil processes, forest growth and succession, and radiative transfer. The model will accommodate spatial scales fro ... Full text Cite

Terra-vision-the integration of scientific analysis into the decision-making process

Journal Article International Journal of Geographical Information Systems · January 1, 1993 Providing an effective tool for risk assessment of terrestrial environmental resources requires a decision support system which will combine scientific analysis and the decision-making process. The goal of such a system is to provide a scientifically-based ... Full text Cite

Implications of natural history traits to system-level dynamics: comparisons of a grassland and a forest

Journal Article Ecological Modelling · January 1, 1993 The importance of life-history traits to vegetation pattern and system-level behavior was evaluated for two North American ecosystems, a semiarid grassland and an eastern deciduous forest. Responses of the systems to spatial and temporal variability in env ... Full text Cite

Modeling vegetation structure-ecosystem process interactions across sites and ecosystems

Journal Article Ecological Modelling · January 1, 1993 We describe an approach to investigating and understanding the interactions between vegetation structure and ecosystem processes that uses simulation models as a framework for comparison and synthesis across ecosystems arrayed along environmental gradients ... Full text Cite

Avian response to landscape pattern: The role of species' life histories

Journal Article Landscape Ecology · September 1, 1992 We suggest that the life histories of species within communities may differ among geographic locations and that communities from distinct biomes may respond uniquely to a given trajectory of landscape change. This paper presents initial tests relevant to t ... Full text Cite

Semivariograms from a forest transect gap model compared with remotely sensed data

Journal Article Journal of Vegetation Science · January 1, 1992 Abstract. A spatially linked version of a forest gap model, ZELIG, parameterized for the H. J. Andrews Experimental Forest, Oregon, was used to generate structural properties (i.e. biomass, leaf area, and maximum tree height) of young (80 yr), mature (140 ... Full text Cite

Spatial applications of gap models

Journal Article Forest Ecology and Management · July 31, 1991 Recent developments in individual-based forest simulators have made it possible to extend the basic approach to a wider range of forest ecosystems. One recent trend is toward more general representations of abiotic processes, and more attention to the role ... Full text Cite

Computer models and long-term ecological research

Journal Article Long-term ecological research · January 1, 1991 Uses two case studies which involve models to simulate system dynamics at differing spatial scales: 1) permafrost in the circumpolar boreal zone, based on long-term research near Fairbanks, Alaska, the models being tested at continental and global scales; ... Cite

The sensitivity of some high-latitude boreal forests to climatic parameters

Journal Article Climatic Change · February 1, 1990 A gap model of environmental processes and vegetation patterns in boreal forests was used to examine the sensitivity of permafrost and permafrostfree forests in interior Alaska to air temperature and precipitation changes. These analyses indicated that in ... Full text Cite

Factors affecting the relative abundances of forest tree species

Journal Article Toward a more exact ecology · January 1, 1989 Reviews a conceptual model of the forest as a dynamic mosaic, and considers the demographic mechanisms that underlie forest dynamics tree establishment, growth and mortality (viewed as qualitatively different phenomena that operate on disparate scales of s ... Cite

Microhabitat pattern and the structure of forest bird communities

Journal Article American Naturalist · 1989 Featured Publication A forest-simulation model was used to generate a data set comprising tree size classes measured on a 9 ha area of contiguous forest over 750 yr, which was then used to examine the role of microhabitat pattern in structuring random assemblages of bird speci ... Full text Cite

Scale, synthesis and ecosystem dynamics

Journal Article Concepts of ecosystem ecology · January 1, 1988 Outlines the behaviour of simple element cycling models in the frequency domain, noting the way in which negative feedback control systems successfully reduce the effects of periodic low frequency inputs, and pointing out that there is an intermediate rang ... Full text Cite

Scale and resolution of forest structural pattern

Journal Article Vegetatio · 1988 Featured Publication An individual tree-based forest succession model was modified to simulate a forest stand as a grid of contiguous 0.01-ha cells. We simulated a 9 ha stand for 750 years and sampled the stand at 50 yr intervals, outputting structural variables for each grid ... Full text Cite