Scaling Issues in Landscape Ecology

Time Periods ◽

Patterns And Processes ◽

Short Time ◽

Spatial patterns are ubiquitous in nature, and ecological systems exhibit patchiness (heterogeneity) across a range of spatial and temporal scales. Landscape ecology is explicitly concerned with understanding how scale affects the measurement of heterogeneity and the scale(s) at which spatial pattern is important for ecological phenomena. Patterns and processes measured at fine spatial scales and over short time periods are unlikely to behave similarly at broader scales and extended time periods. An understanding of pattern-process linkages, a major research focus in landscape ecology, thus requires an understanding of how patterns change with scale, spatially and temporally. The development of methods for extrapolating information across scales is necessary for predicting how landscapes will change over time as well as for ecological forecasting. This chapter explores how scaling issues affect ecological investigations, discusses problems in identifying the correct scale for research, and outlines when and how ecological data can be extrapolated.

Landscape Heterogeneity and Dynamics

Essentials of Landscape Ecology ◽

10.1093/oso/9780198838388.003.0003 ◽

2019 ◽

pp. 42-126

Author(s):

Kimberly A. With

Keyword(s):

Landscape Ecology ◽

Spatial Heterogeneity ◽

Landscape Structure ◽

Landscape Heterogeneity ◽

Spatial Scales ◽

Anthropogenic Disturbances ◽

Ecological Processes ◽

Disturbance Dynamics ◽

Wide Range ◽

Heterogeneity is a defining characteristic of landscapes and therefore central to the study of landscape ecology. Landscape ecology investigates what factors give rise to heterogeneity, how that heterogeneity is maintained or altered by natural and anthropogenic disturbances, and how heterogeneity ultimately influences ecological processes and flows across the landscape. Because heterogeneity is expressed across a wide range of spatial scales, the landscape perspective can be applied to address these sorts of questions at any level of ecological organization, and in aquatic and marine systems as well as terrestrial ones. Disturbances—both natural and anthropogenic—are a ubiquitous feature of any landscape, contributing to its structure and dynamics. Although the focus in landscape ecology is typically on spatial heterogeneity, disturbance dynamics produce changes in landscape structure over time as well as in space. Heterogeneity and disturbance dynamics are thus inextricably linked and are therefore covered together in this chapter.

How to consider history in landscape ecology: patterns, processes, and pathways

Landscape Ecology ◽

10.1007/s10980-020-01163-w ◽

2020 ◽

Author(s):

Ulrike Tappeiner ◽

Georg Leitinger ◽

Anita Zariņa ◽

Matthias Bürgi

Keyword(s):

Landscape Ecology ◽

Landscape Change ◽

Path Dependence ◽

Complete Analysis ◽

The Past ◽

Natural Landscapes ◽

Patterns And Processes ◽

Event Chains ◽

Abstract Context Landscape ecology early on developed the awareness that central objects of investigation are not stable over time and therefore the historical dimension must be included, or at least considered. Objectives This paper considers the importance of history in landscape ecology in terms of its impact on patterns and processes and proposes to complement these with the notion of pathways in order to provide a comprehensive analysis of landscape change. Methods We develop a conceptual framework distinguishing between legacy effects, which include pattern and processes, and path dependence, with a focus of development pathways and we illustrate these perspectives by empirical examples. Results Combined short- to long-lasting imprints and legacies of historical patterns and processes reveal how present patterns and processes are in various ways influenced by legacies of the past. The focus on inherent dynamics of development pathways sheds light on the process of change itself, and its trajectories, and reveals the role of event chains and institutional reproduction. Conclusions Understanding patterns, processes, and pathways over time, allows a more complete analysis of landscape change, and forms the base to preserve vital ecosystem services of both human-made and natural landscapes for the future.

Patterns and processes of sediment sorting in gravel-bed rivers

Progress in Physical Geography Earth and Environment ◽

10.1177/030913339802200101 ◽

1998 ◽

Vol 22 (1) ◽

pp. 1-32 ◽

Cited By ~ 83

Author(s):

D. Mark Powell

Keyword(s):

Spatial Scales ◽

Coarse Grained ◽

Transport Pathways ◽

Rough Bed ◽

Grain Size Distributions ◽

Coarse Surface ◽

Sediment Sorting ◽

Patterns And Processes ◽

Bed Material

Sedimentological studies of coarse-grained alluvial rivers reveal patterns of bed material sorting at a variety of spatial scales ranging from downstream fining over the length of the long profile to the vertical segregation of a coarse surface layer at the scale of individual particles. This article reviews the mechanisms that sort bed material by size during sediment entrainment, transport and deposition and discusses some of the inter-relationships that exist between patterns and processes of sediment sorting at different spatial and temporal scales. At initiation of motion, sorting can arise from the preferential entrainment of the finer fractions from the heterogeneous bed sediments. Bedload grain-size distributions are modified during transport as different size fractions are routed along different transport pathways under the influence of nonuniform bed topography and associated flow patterns, and during deposition as the variable pocket geometry of the rough bed surface and turbulence intensity of the flow control the size of the particles that deposit. The review highlights the poor understanding of the many feedback linkages that exist between patterns and processes of sediment sorting at different scales and the need for a greater awareness of the spatial and temporal bounds of these linkages.

Not all ponds are created equal: long-term beaver (Castor canadensis) lodge occupancy in a heterogeneous landscape

Canadian Journal of Zoology ◽

10.1139/cjz-2019-0066 ◽

2020 ◽

Vol 98 (3) ◽

pp. 210-218 ◽

Cited By ~ 1

Author(s):

G.A. Hood

Keyword(s):

Habitat Selection ◽

Spatial Scales ◽

Castor Canadensis ◽

Site Occupancy ◽

Occupancy Models ◽

Habitat Features ◽

Non Linear ◽

Original Habitat ◽

Short Time

Modeling habitat selection often represents single spatial scales and short time periods. However, for species that dramatically modify environments upon initial colonization, non-linear interactions change original habitat to one where habitat selection is confounded by subsequent modifications by the organism itself. The ability of beavers (Castor canadensis Kuhl, 1820) to dramatically alter habitat components over time makes them a model species for examining habitat selection spatially and temporally. This study identified habitat features selected by a relatively long-lived, colonial species, and how selection influenced site occupancy over varying spatial scales. Remote sensing and field data provided spatial and temporal coverage of four measures of occupancy. Models of occupancy over an 11-year period, combined with environmental variables, identified features influencing occupancy, abandonment, and recolonization at 30, 50, and 100 m scales. Unlike many studies, % deciduous was a poor predictor of occupancy. Instead, pond area, % grassland, distance to a pond that was active at least once, and standard deviation (SD) of slope were important variables. SD of slope was the only variable not influenced by beavers. Examining species–habitat relationships over broader spatial and temporal scales, particularly for ecosystem engineers, enhances understanding of non-linear effects and how they influence perceptions of habitat selection.

Critical Zone Science in the Anthropocene: Opportunities for biogeographic and ecological theory and praxis to drive earth science integration

Progress in Physical Geography Earth and Environment ◽

10.1177/0309133319864268 ◽

2019 ◽

Vol 44 (1) ◽

pp. 50-69 ◽

Cited By ~ 4

Author(s):

Jesse Minor ◽

Jessie K Pearl ◽

Mallory L Barnes ◽

Tony R Colella ◽

Patrick C Murphy ◽

...

Keyword(s):

Earth Science ◽

Spatial Scales ◽

Abiotic Factors ◽

Climate Change Impacts ◽

Critical Zone ◽

Shallow Subsurface ◽

Rate Dependent ◽

Patterns And Processes ◽

Earth’S Critical Zone

Critical Zone Science (CZS) represents a powerful confluence of research agendas, tools, and techniques for examining the complex interactions between biotic and abiotic factors located at the interface of the Earth’s surface and shallow subsurface. Earth’s Critical Zone houses and sustains terrestrial life, and its interacting subsystems drive macroecological patterns and processes at a variety of spatial scales. Despite the analytical power of CZS to understand and characterize complicated rate-dependent processes, CZS has done less to capture the effects of disturbance and anthropogenic influences on Critical Zone processes, although some Critical Zone Observatories focus on disturbance and regeneration. Methodological approaches from biogeography and ecology show promise for providing Critical Zone researchers with tools for incorporating the effects of ecological and anthropogenic disturbance into fine-grained studies of important Earth processes. Similarly, mechanistic insights from CZS can inform biogeographical and ecological interpretations of pattern and process that operate over extensive spatial and temporal scales. In this paper, we illustrate the potential for productive nexus opportunities between CZS, biogeography, and ecology through use of an integrated model of energy and mass flow through various subsystems of the Earth’s Critical Zone. As human-induced effects on biotic and abiotic components of global ecosystems accelerate in the Anthropocene, we argue that the long temporal and broad spatial scales traditionally studied in biogeography can be constructively combined with the quantifiable processes of energy and mass transfer through the Critical Zone to answer pressing questions about future trajectories of land cover change, post-disturbance recovery, climate change impacts, and urban hydrology and ecology.

Spatial patterns and spread of exotic earthworms at local scales

Canadian Journal of Zoology ◽

10.1139/cjz-2014-0197 ◽

2015 ◽

Vol 93 (9) ◽

pp. 721-726 ◽

Cited By ~ 11

Author(s):

Erin K. Cameron ◽

Erin M. Bayne

Keyword(s):

Spatial Patterns ◽

Native Species ◽

Spatial Scales ◽

Local Level ◽

Long Distance ◽

Invasive Spread ◽

Exotic Earthworms ◽

Changes Over Time ◽

Northeastern Alberta ◽

Given the substantial impacts of non-native species on invaded systems, an understanding of the rates and spatial patterns of invasive spread is critical. Spread may vary across spatial scales, with dispersal of invasive species occurring both via diffusive spread at local sites and long-distance jump dispersal at larger scales. Research on earthworm invasions in North American forests has focused on patterns of spread across landscapes, with less examination of spread at local sites. We sampled the exotic earthworm Dendrobaena octaedra (Savigny, 1826) on 500 m × 500 m grids at three sites in the boreal forest of northeastern Alberta in 2006 and again in 2012–2013 to examine distributional changes over time. Earthworms spread farther from roads (the presumed site of initial introduction) over time, and spatial patterns at our sites suggest transport by vehicles and waterways are key vectors of dispersal at the local level. Spread was estimated to be occurring at a rate of at least 17.9 m/year. Our study indicates that both diffusive spread and jump dispersal of earthworms can be important at local scales and that local diffusive spread may be substantially higher than previously estimated.

Analysis of 220 Years of Floodplain Population Dynamics in the US at Different Spatial Scales

Water ◽

10.3390/w13020141 ◽

2021 ◽

Vol 13 (2) ◽

pp. 141

Author(s):

Firoza Akhter ◽

Maurizio Mazzoleni ◽

Luigia Brandimarte

Keyword(s):

Population Dynamics ◽

Large Scale ◽

Spatial Scales ◽

National Level ◽

State Level ◽

Economic Activities ◽

Protection Measures ◽

Management Planning ◽

The Us ◽

In this study, we explore the long-term trends of floodplain population dynamics at different spatial scales in the contiguous United States (U.S.). We exploit different types of datasets from 1790–2010—i.e., decadal spatial distribution for the population density in the US, global floodplains dataset, large-scale data of flood occurrence and damage, and structural and nonstructural flood protection measures for the US. At the national level, we found that the population initially settled down within the floodplains and then spread across its territory over time. At the state level, we observed that flood damages and national protection measures might have contributed to a learning effect, which in turn, shaped the floodplain population dynamics over time. Finally, at the county level, other socio-economic factors such as local flood insurances, economic activities, and socio-political context may predominantly influence the dynamics. Our study shows that different influencing factors affect floodplain population dynamics at different spatial scales. These facts are crucial for a reliable development and implementation of flood risk management planning.

Structured and Systematic Team and Procedure Training in Severe Trauma: Going from ‘Zero to Hero’ for a Time-Critical, Low-Volume Emergency Procedure Over Three Time Periods

World Journal of Surgery ◽

10.1007/s00268-021-05980-1 ◽

2021 ◽

Vol 45 (5) ◽

pp. 1340-1348

Author(s):

Maryam Meshkinfamfard ◽

Jon Kristian Narvestad ◽

Johannes Wiik Larsen ◽

Arezo Kanani ◽

Jørgen Vennesland ◽

...

Keyword(s):

Injury Severity ◽

Trauma System ◽

Severe Trauma ◽

Emergency Procedure ◽

Emergency Thoracotomy ◽

Severity Scores ◽

Time Periods ◽

Low Volume ◽

Time Critical ◽

Abstract Background Resuscitative emergency thoracotomy is a potential life-saving procedure but is rarely performed outside of busy trauma centers. Yet the intervention cannot be deferred nor centralized for critically injured patients presenting in extremis. Low-volume experience may be mitigated by structured training. The aim of this study was to describe concurrent development of training and simulation in a trauma system and associated effect on one time-critical emergency procedure on patient outcome. Methods An observational cohort study split into 3 arbitrary time-phases of trauma system development referred to as ‘early’, ‘developing’ and ‘mature’ time-periods. Core characteristics of the system is described for each phase and concurrent outcomes for all consecutive emergency thoracotomies described with focus on patient characteristics and outcome analyzed for trends in time. Results Over the study period, a total of 36 emergency thoracotomies were performed, of which 5 survived (13.9%). The “early” phase had no survivors (0/10), with 2 of 13 (15%) and 3 of 13 (23%) surviving in the development and mature phase, respectively. A decline in ‘elderly’ (>55 years) patients who had emergency thoracotomy occurred with each time period (from 50%, 31% to 7.7%, respectively). The gender distribution and the injury severity scores on admission remained unchanged, while the rate of patients with signs on life (SOL) increased over time. Conclusion The improvement over time in survival for one time-critical emergency procedure may be attributed to structured implementation of team and procedure training. The findings may be transferred to other low-volume regions for improved trauma care.

Seasonal Estimates and Uncertainties of Snow Accumulation from CloudSat Precipitation Retrievals

Atmosphere ◽

10.3390/atmos12030363 ◽

2021 ◽

Vol 12 (3) ◽

pp. 363

Author(s):

George Duffy ◽

Fraser King ◽

Ralf Bennartz ◽

Christopher G. Fletcher

Keyword(s):

Time Scales ◽

Snow Water Equivalent ◽

Spatial Scales ◽

Snow Accumulation ◽

High Latitudes ◽

Percentage Points ◽

Snow Water ◽

Time Periods ◽

Predicted Values ◽

Good Agreement

CloudSat is often the only measurement of snowfall rate available at high latitudes, making it a valuable tool for understanding snow climatology. The capability of CloudSat to provide information on seasonal and subseasonal time scales, however, has yet to be explored. In this study, we use subsampled reanalysis estimates to predict the uncertainties of CloudSat snow water equivalent (SWE) accumulation measurements at various space and time resolutions. An idealized/simulated subsampling model predicts that CloudSat may provide seasonal SWE estimates with median percent errors below 50% at spatial scales as small as 2° × 2°. By converting these predictions to percent differences, we can evaluate CloudSat snowfall accumulations against a blend of gridded SWE measurements during frozen time periods. Our predictions are in good agreement with results. The 25th, 50th, and 75th percentiles of the percent differences between the two measurements all match predicted values within eight percentage points. We interpret these results to suggest that CloudSat snowfall estimates are in sufficient agreement with other, thoroughly vetted, gridded SWE products. This implies that CloudSat may provide useful estimates of snow accumulation over remote regions within seasonal time scales.

A Comparison between One-Step and Two-Step Nesting Strategy in the Dynamical Downscaling of Regional Climate Model COSMO-CLM at 2.2 km Driven by ERA5 Reanalysis

Atmosphere ◽

10.3390/atmos12020260 ◽

2021 ◽

Vol 12 (2) ◽

pp. 260

Author(s):

Mario Raffa ◽

Alfredo Reder ◽

Marianna Adinolfi ◽

Paola Mercogliano

Keyword(s):

Regional Climate Model ◽

Climate Model ◽

Dynamical Downscaling ◽

Spatial Scales ◽

Regional Climate ◽

Weather Forecast ◽

Medium Range Weather Forecast ◽

Starting Point ◽

One Step

Recently, the European Centre for Medium Range Weather Forecast (ECMWF) has released a new generation of reanalysis, acknowledged as ERA5, representing at the present the most plausible picture for the current climate. Although ERA5 enhancements, in some cases, its coarse spatial resolution (~31 km) could still discourage a direct use of precipitation fields. Such a gap could be faced dynamically downscaling ERA5 at convection permitting scale (resolution < 4 km). On this regard, the selection of the most appropriate nesting strategy (direct one-step against nested two-step) represents a pivotal issue for saving time and computational resources. Two questions may be raised within this context: (i) may the dynamical downscaling of ERA5 accurately represents past precipitation patterns? and (ii) at what extent may the direct nesting strategy performances be adequately for this scope? This work addresses these questions evaluating two ERA5-driven experiments at ~2.2 km grid spacing over part of the central Europe, run using the regional climate model COSMO-CLM with different nesting strategies, for the period 2007–2011. Precipitation data are analysed at different temporal and spatial scales with respect to gridded observational datasets (i.e., E-OBS and RADKLIM-RW) and existing reanalysis products (i.e., ERA5-Land and UERRA). The present work demonstrates that the one-step experiment tendentially outperforms the two-step one when there is no spectral nudging, providing results at different spatial and temporal scales in line with the other existing reanalysis products. However, the results can be highly model and event dependent as some different aspects might need to be considered (i.e., the nesting strategies) during the configuration phase of the climate experiments. For this reason, a clear and consolidated recommendation on this topic cannot be stated. Such a level of confidence could be achieved in future works by increasing the number of cities and events analysed. Nevertheless, these promising results represent a starting point for the optimal experimental configuration assessment, in the frame of future climate studies.