Spatial patterns and spread of exotic earthworms at local scales

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.

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Scaling Issues in Landscape Ecology

Essentials of Landscape Ecology ◽

10.1093/oso/9780198838388.003.0002 ◽

2019 ◽

pp. 14-41

Author(s):

Kimberly A. With

Keyword(s):

Landscape Ecology ◽

Spatial Patterns ◽

Spatial Scales ◽

Ecological Data ◽

Ecological Forecasting ◽

Spatial And Temporal Scales ◽

Time Periods ◽

Patterns And Processes ◽

Short Time ◽

Over 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.

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Shifting Local, Regional, and Interregional Relations in Middle Horizon Peru: Evidence from La Real

Latin American Antiquity ◽

10.7183/1045-6635.26.3.382 ◽

2015 ◽

Vol 26 (3) ◽

pp. 382-400 ◽

Cited By ~ 6

Author(s):

Justin Jennings ◽

Tiffiny A. Tung ◽

Willy J. Yépez Álvarez ◽

Gladys Cecilia Quequezana Lucano ◽

Marko Alfredo López Hurtado

Keyword(s):

Social Stratification ◽

Long Distance ◽

Middle Horizon ◽

Lethal Violence ◽

Interregional Interaction ◽

The Andes ◽

A Site ◽

Long Distance Movement ◽

Changes Over Time ◽

Over Time

The Middle Horizon (ca. A.D. 600-1100) was a period of great change in the Andes, with much of Perú connected through long-distance exchange and widely shared Wari styles and practices. Recent research has begun to detail the transformations that occurred within the period, leading to questions about the development of the Wari state and its shifting relationships with outlying areas over time. This article expands this research by exploring the temporal differences within a funerary assemblage at La Real, a site in the Majes Valley of southern Perú. The artifacts and human remains from La Real are used to explore Middle Horizon dynamism in relation to both the surging interregional interaction of the period and emergent social stratification in the valley. Mortuary profiles and sublethal violence remain fairly constant throughout the period, but lethal violence significantly increases in the late Middle Horizon. There are also significant changes over time in the presence of exotic goods and other items, reflecting an increase in craft specialization, the adoption of Wari-related styles and practices, and the development of a more regionally oriented economy. The role of the Wari state in these changes, although unclear, may relate to attempts by Wari leaders to manipulate the long-distance movement of a restricted group of artifacts and resources.

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Designing Dynamic Delivery Parking Spots in Urban Areas to Reduce Traffic Disruptions

Journal of Advanced Transportation ◽

10.1155/2017/6296720 ◽

2017 ◽

Vol 2017 ◽

pp. 1-15 ◽

Cited By ~ 12

Author(s):

Mireia Roca-Riu ◽

Jin Cao ◽

Igor Dakic ◽

Monica Menendez

Keyword(s):

Urban Areas ◽

Local Level ◽

Hydrodynamic Theory ◽

Time Varying ◽

Traffic Demand ◽

Road Space ◽

Delivery Services ◽

Negative Impacts ◽

Changes Over Time ◽

Over Time

Pick-up and delivery services are essential for businesses in urban areas. However, due to the limited space in city centers, it might be unfeasible to provide sufficient loading/unloading spots. As a result, this type of operations often interferes with traffic by occupying road space (e.g., illegal parking). In this study, a potential solution is investigated: Dynamic Delivery Parking Spots (DDPS). With this concept, based on the time-varying traffic demand, the area allowed for delivery parking changes over time in order to maximize delivery opportunities while reducing traffic disruptions. Using the hydrodynamic theory of traffic flow, we analyze the traffic discharging rate on an urban link with DDPS. In comparison to the situation without delivery parking, the results show that although DDPS occupy some space on a driving lane, it is possible to keep the delay at a local level, that is, without spreading to the network. In this paper, we provide a methodology for the DDPS design, so that the delivery requests can be satisfied while their negative impacts on traffic are reduced. A simulation study is used to validate the model and to estimate delay compared to real situations with illegal parking, showing that DDPS can reduce system’s delay.

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Monitoring methods and spatial patterns of European canker disease in commercial orchards

New Zealand Plant Protection ◽

10.30843/nzpp.2016.69.5883 ◽

2016 ◽

Vol 69 ◽

pp. 213-220 ◽

Cited By ~ 2

Author(s):

R.E. Campbell ◽

S. Roy ◽

T. Curnow ◽

M. Walter

Keyword(s):

Spatial Pattern ◽

Disease Control ◽

Spatial Patterns ◽

Disease Incidence ◽

Systematic Sampling ◽

Monitoring Methods ◽

Canker Disease ◽

Single Row ◽

Changes Over Time ◽

Over Time

European canker (Neonectria ditissima) kills trees and decreases production in apple orchards To determine a level of disease control or the extent of its spread in commercial orchards efficient monitoring methods are required In this study we investigated two monitoring methods sampling a single row and systematic sampling of an orchard block The spatial pattern of disease within blocks and whether this changes over time was also investigated The accuracy of singlerow monitoring depended on the level of canker in the orchard and the patchiness of the distribution of infected trees However singlerow monitoring tracked changes over time in incidence severity and type of canker sufficiently well and was efficient The spatial patterns of disease incidence across the blocks were nonrandom but showed hotspots which did not change significantly over time

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Reliability of T-WSI to Evaluate Neighborhoods Walkability and Its Changes over Time

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph17217709 ◽

2020 ◽

Vol 17 (21) ◽

pp. 7709

Author(s):

Daniela D’Alessandro ◽

Diego Valeri ◽

Letizia Appolloni

Keyword(s):

Physical Activity ◽

Correlation Coefficient ◽

Local Level ◽

Intraclass Correlation ◽

Urban Neighborhoods ◽

Easy Method ◽

Weighted Analysis ◽

Suitability Index ◽

Changes Over Time ◽

Over Time

More walkable neighborhoods are linked to increased physical activity. The Walking Suitability Index of the territory (T-WSI) is an easy method to evaluate walkability on the basis of direct observation. T-WSI provides 12 indicators divided into 4 categories (practicability, safety, urbanity, pleasantness); the weighted analysis of these indicators gives an overall score of the actual usability of the neighborhood. The aim of the study is to evaluate the ability of T-WSI’ indicators to measure, in a reliable way, any street’s walkability variations occurred over time. The investigation was performed in 2018 in nine urban neighborhoods of Rieti city. Cronbach’s α is used to evaluate internal consistency of T-WSI; Intraclass Correlation Coefficient (ICC) is used to evaluate the reproducibility of measurements (or ratings) made by different investigators. Cronbach’s α is 0.89 (± 0.02); ICC is also good (ICC = 0.89; 95% CI: 0.84–0.92). The results of the 2018 investigation are also compared with those collected in 2016 in the same districts. The results show that T-WSI is a reliable and easy to use tool, useful to measure the effectiveness of the interventions already realized at local level, but it could also contribute to making decisions to develop regeneration projects.

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Comparison of two devices for measuring exercise transcutaneous oxygen pressures in patients with claudication

VASA ◽

10.1024/0301-1526/a000454 ◽

2015 ◽

Vol 44 (5) ◽

pp. 355-362 ◽

Cited By ~ 8

Author(s):

Marie Urban ◽

Alban Fouasson-Chailloux ◽

Isabelle Signolet ◽

Christophe Colas Ribas ◽

Mathieu Feuilloy ◽

...

Keyword(s):

Oxygen Pressure ◽

Optical Sensors ◽

Chemical Sensors ◽

Transcutaneous Oxygen ◽

Starting Values ◽

Two Systems ◽

Transcutaneous Oxygen Pressure ◽

New Sensors ◽

Changes Over Time ◽

Over Time

Abstract. Summary: Background: We aimed at estimating the agreement between the Medicap® (photo-optical) and Radiometer® (electro-chemical) sensors during exercise transcutaneous oxygen pressure (tcpO2) tests. Our hypothesis was that although absolute starting values (tcpO2rest: mean over 2 minutes) might be different, tcpO2-changes over time and the minimal value of the decrease from rest of oxygen pressure (DROPmin) results at exercise shall be concordant between the two systems. Patients and methods: Forty seven patients with arterial claudication (65 + / - 7 years) performed a treadmill test with 5 probes each of the electro-chemical and photo-optical devices simultaneously, one of each system on the chest, on each buttock and on each calf. Results: Seventeen Medicap® probes disconnected during the tests. tcpO2rest and DROPmin values were higher with Medicap® than with Radiometer®, by 13.7 + / - 17.1 mm Hg and 3.4 + / - 11.7 mm Hg, respectively. Despite the differences in absolute starting values, changes over time were similar between the two systems. The concordance between the two systems was approximately 70 % for classification of test results from DROPmin. Conclusions: Photo-optical sensors are promising alternatives to electro-chemical sensors for exercise oximetry, provided that miniaturisation and weight reduction of the new sensors are possible.

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