Assessing spatial attributes of forest landscape values: an internet-based participatory mapping approach

2008 ◽  
Vol 38 (2) ◽  
pp. 289-303 ◽  
Author(s):  
Jennifer L. Beverly ◽  
Kinga Uto ◽  
Justin Wilkes ◽  
Peter Bothwell
Keyword(s):  
Biological Diversity ◽  
Spatial Scales ◽  
Point Pattern Analysis ◽  
Point Pattern ◽  
Forest Landscape ◽  
Hotspot Detection ◽  
Road Density ◽  
Landscape Values ◽  
Forest Fire Management ◽  
Value Types

We designed and developed an internet mapping application to collect data on the locations of forest landscape values across a 2.4 million hectare study area in the province of Alberta, Canada. Four communities in the study area were surveyed and 8053 point locations were mapped for 10 different value types. Importance weights of landscape values were determined through a ranking exercise. Nearest-neighbour and second-order spatial point pattern analysis (K functions) suggested that all value types were significantly clustered across the study area. Recreational, wilderness, existence, and biological diversity values exhibited maximum clustering at larger spatial scales in comparison with educational, economic, historic or cultural, and spiritual values. Maximum clustering was positively related to mean road density and negatively related to mean distance to water, which suggests that landscape features influence the spatial pattern of values by acting as focal points or attractors for values. An applied use of the data for values hotspot detection and community protection zoning in forest fire management planning is presented.

scholarly journals Land-use history impacts spatial patterns and composition of woody plant species across a 35-hectare temperate forest plot

PeerJ ◽  
2022 ◽  
Vol 10 ◽  
pp. e12693
Author(s):  
David A. Orwig ◽  
Jason A. Aylward ◽  
Hannah L. Buckley ◽  
Bradley S. Case ◽  
Aaron M. Ellison
Keyword(s):  
Land Use ◽  
Pattern Analysis ◽  
Resource Competition ◽  
Spatial Scales ◽  
Acer Rubrum ◽  
Point Pattern Analysis ◽  
Point Pattern ◽  
Forest Plot ◽  
Land Use History ◽  
Composition And Structure

Land-use history is the template upon which contemporary plant and tree populations establish and interact with one another and exerts a legacy on the structure and dynamics of species assemblages and ecosystems. We use the first census (2010–2014) of a 35-ha forest-dynamics plot at the Harvard Forest in central Massachusetts to describe the composition and structure of the woody plants in this plot, assess their spatial associations within and among the dominant species using univariate and bivariate spatial point-pattern analysis, and examine the interactions between land-use history and ecological processes. The plot includes 108,632 live stems ≥ 1 cm in diameter (2,215 individuals/ha) and 7,595 standing dead stems ≥ 5 cm in diameter. Live tree basal area averaged 42.25 m2/ha, of which 84% was represented by Tsuga canadensis (14.0 m2/ ha), Quercus rubra (northern red oak; 9.6 m2/ ha), Acer rubrum (7.2 m2/ ha) and Pinus strobus (eastern white pine; 4.4 m2/ ha). These same four species also comprised 78% of the live aboveground biomass, which averaged 245.2 Mg/ ha. Across all species and size classes, the forest contains a preponderance (> 80,000) of small stems (<10-cm diameter) that exhibit a reverse-J size distribution. Significant spatial clustering of abundant overstory species was observed at all spatial scales examined. Spatial distributions of A. rubrum and Q. rubra showed negative intraspecific correlations in diameters up to at least a 150-m spatial lag, likely indicative of crowding effects in dense forest patches following intensive past land use. Bivariate marked point-pattern analysis, showed that T. canadensis and Q. rubra diameters were negatively associated with one another, indicating resource competition for light. Distribution and abundance of the common overstory species are predicted best by soil type, tree neighborhood effects, and two aspects of land-use history: when fields were abandoned in the late 19th century and the succeeding forest types recorded in 1908. In contrast, a history of intensive logging prior to 1950 and a damaging hurricane in 1938 appear to have had little effect on the distribution and abundance of present-day tree species. Our findings suggest that current day composition and structure are still being influenced by anthropogenic disturbances that occurred over a century ago.

scholarly journals Spatial point-pattern analysis as a powerful tool in identifying pattern-process relationships in plant ecology: an updated review

2021 ◽  
Vol 10 (1) ◽  
Author(s):  
Mariem Ben-Said
Keyword(s):  
Spatial Patterns ◽  
Pattern Analysis ◽  
Biotic Interactions ◽  
Plant Ecology ◽  
Point Pattern Analysis ◽  
Point Pattern ◽  
Summary Statistics ◽  
Spatial Point Pattern ◽  
Spatial Point ◽  
Spatial Point Pattern Analysis

Abstract Background Ecological processes such as seedling establishment, biotic interactions, and mortality can leave footprints on species spatial structure that can be detectable through spatial point-pattern analysis (SPPA). Being widely used in plant ecology, SPPA is increasingly carried out to describe biotic interactions and interpret pattern-process relationships. However, some aspects are still subjected to a non-negligible debate such as required sample size (in terms of the number of points and plot area), the link between the low number of points and frequently observed random (or independent) patterns, and relating patterns to processes. In this paper, an overview of SPPA is given based on rich and updated literature providing guidance for ecologists (especially beginners) on summary statistics, uni-/bi-/multivariate analysis, unmarked/marked analysis, types of marks, etc. Some ambiguities in SPPA are also discussed. Results SPPA has a long history in plant ecology and is based on a large set of summary statistics aiming to describe species spatial patterns. Several mechanisms known to be responsible for species spatial patterns are actually investigated in different biomes and for different species. Natural processes, plant environmental conditions, and human intervention are interrelated and are key drivers of plant spatial distribution. In spite of being not recommended, small sample sizes are more common in SPPA. In some areas, periodic forest inventories and permanent plots are scarce although they are key tools for spatial data availability and plant dynamic monitoring. Conclusion The spatial position of plants is an interesting source of information that helps to make hypotheses about processes responsible for plant spatial structures. Despite the continuous progress of SPPA, some ambiguities require further clarifications.

Potential contact statistics for measuring scale-dependent spatial pattern and association: an example of northern cod (Gadus morhua) and capelin (Mallotus villosus)

2000 ◽  
Vol 57 (7) ◽  
pp. 1355-1368 ◽  
Author(s):  
Richard L O'Driscoll ◽  
David C Schneider ◽  
George A Rose ◽  
George R Lilly
Keyword(s):  
Spatial Distribution ◽  
Spatial Pattern ◽  
Gadus Morhua ◽  
Atlantic Cod ◽  
Simulated Data ◽  
Point Pattern Analysis ◽  
Point Pattern ◽  
Mallotus Villosus ◽  
Capelin Mallotus Villosus ◽  
Potential Contact

Analysis of simulated data showed that potential contact statistics could be used to describe spatial pattern in sample density data. Potential contact is a new method, analogous to Ripley's K function for mapped point pattern analysis. Potential contact can be used to describe spatial pattern and association over a range of scales without grouping data and is robust against the presence of zeros. The statistical output is ecologically interpretable, as a measure of the degree of contact between individuals. This new technique was applied to examine changes in the spatial distribution of Atlantic cod (Gadus morhua) off Newfoundland, Canada, from 1985 to 1994, a period that encompassed a collapse of the cod stock. Sample data from bottom-trawl surveys indicated that cod were aggregated in patches with dimensions of 100-250 km. During the period of cod decline in the 1990s, spatial structure changed in three ways: the number of patches decreased, patch size shrank, and contact with conspecifics at small (10-20 km) scales fell. Cod were broadly associated with capelin (Mallotus villosus), a major prey species. Spatial distribution of capelin changed over the same time period as changes in cod distribution, and there was no evidence that contact between cod and capelin decreased.

scholarly journals Spatial and temporal drivers of wildfire occurrence in the context of rural development in northern Wisconsin, USA

2012 ◽  
Vol 21 (2) ◽  
pp. 141 ◽  
Author(s):  
Brian R. Miranda ◽  
Brian R. Sturtevant ◽  
Susan I. Stewart ◽  
Roger B. Hammer
Keyword(s):  
Linear Regression ◽  
Land Use Planning ◽  
Temporal Trends ◽  
Point Pattern Analysis ◽  
Annual Number ◽  
Point Pattern ◽  
Linear Regression Models ◽  
Housing Density ◽  
Spatial And Temporal Scales ◽  
Wildfire Occurrence

Most drivers underlying wildfire are dynamic, but at different spatial and temporal scales. We quantified temporal and spatial trends in wildfire patterns over two spatial extents in northern Wisconsin to identify drivers and their change through time. We used spatial point pattern analysis to quantify the spatial pattern of wildfire occurrences, and linear regression to quantify the influence of drought and temporal trends in annual number and mean size of wildfires. Analyses confirmed drought as an important driver of both occurrences and fire size. When both drought and time were incorporated in linear regression models, the number of wildfires showed a declining trend across the full study area, despite housing density increasing in magnitude and spatial extent. Fires caused by campfires and debris-burning did not show any temporal trends. Comparison of spatial models representing biophysical, anthropogenic and combined factors demonstrated human influences on wildfire occurrences, especially human activity, infrastructure and property values. We also identified a non-linear relationship between housing density and wildfire occurrence. Large wildfire occurrence was predicted by similar variables to all occurrences, except the direction of influence changed. Understanding these spatial and temporal drivers of wildfire occurrence has implications for land-use planning, wildfire suppression strategies and ecological goals.

Spatiotemporal Point Pattern Analysis Using Ripley's K Function

2017 ◽  
pp. 155-176
Author(s):  
Alexander Hohl ◽  
Minrui Zheng ◽  
Wenwu Tang ◽  
Eric Delmelle ◽  
Irene Casas
Keyword(s):  
Pattern Analysis ◽  
Point Pattern Analysis ◽  
Point Pattern ◽  
Ripley’S K Function ◽  
Ripley’S K ◽  
Ripley's K ◽  
K Function

scholarly journals Schistosoma japonicum infected sentinel mice surveillance and spatial point pattern analysis in Hubei province, China, 2010-2018

2020 ◽  
Author(s):  
Yan-Yan Chen ◽  
Si Liu ◽  
Xiao-Wei Shan ◽  
Hui Wang ◽  
Bo Li ◽  
...  
Keyword(s):  
High Risk ◽  
Schistosoma Japonicum ◽  
Density Estimation ◽  
Kernel Density Estimation ◽  
Kernel Density ◽  
Hubei Province ◽  
Point Pattern Analysis ◽  
Point Pattern ◽  
Infection Pattern ◽  
Risk Areas

Abstract Background Progress in national schistosomiasis control in China has successfully reduced disease transmission in many districts. However, a low transmission rate hinders conventional snail surveys in identifying areas at risk. In this study, Schistosoma japonicum infected sentinel mice surveillance was conducted to identify high risk areas of schistosomiasis transmission in Hubei province, China. Methods The risk of schistosomiasis transmission was assessed using sentinel mice monitoring in Hubei province from 2010 to 2018. Field detections were carried out in June and September and the sentinel mice were kept for approximately 35 days in a laboratory. Then they were dissected to determine whether schistosome infection was present. Ripley’s K-function and kernel density estimation were applied to analyze the spatial distribution and positive point pattern of schistosomiasis transmission. Results A total of 190 sentinel mouse surveillance sites were selected to detect areas of schistosomiasis infection from 2010 to 2018, with 29 sites showing infected mice (15.26%).A total of 4723 mice were dissected and112 infected mice containing 256 adult worms were detected. The infection rate was 2.37% and an average of 2.28 worms was detected per infected mouse. Significantly more infected mice were detected in June samples than in September samples (x2 = 12.11, P < 0.01).Ripley's L(d) index analysis showed that, when distance was less than or equal to 34.52 km, the sentinel mice infection pattern showed aggregation, with the strongest aggregation occurring at 7.86 km. Three hotspots were detected using kernel density estimation, namely: at the junction of Jingzhou District, Gong’an County and Shashi District in Jingzhou City; in Wuhan city at the border of the Huangpi and Dongxihu Districts and in the Hanan and Caidian Districts. Conclusion The results showed sentinel mice surveillance was useful in identifying high-risk areas and could provide valuable information for schistosomiasis prevention and control, especially concerning areas along the Yangtze River such as the Fu-Lun, Dongjing-Tongshun and Juzhang River basins.

scholarly journals Characteristics and factors influencing the natural regeneration of Larix principis-rupprechtii seedlings in northern China

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e12327
Author(s):  
Weiwen Zhao ◽  
Wenjun Liang ◽  
Youzhi Han ◽  
Xi Wei
Keyword(s):  
Spatial Distribution ◽  
Natural Regeneration ◽  
Pair Correlation ◽  
Principal Component ◽  
Northern China ◽  
Point Pattern Analysis ◽  
Point Pattern ◽  
Adult Trees ◽  
Herb Diversity ◽  
Univariate Distribution

Larix principis-rupprechtii is an important and widely distributed species in the mountains of northern China. However, it has inefficient natural regeneration in many stands and difficulty recruiting seedlings and saplings. In this study, we selected six plots with improved naturally-regenerated L. principis-rupprechtii seedlings. A point pattern analysis (pair-correlation function) was applied to identify the spatial distribution pattern and correlation between adult trees and regenerated seedlings mapped through X/Y coordinates. Several possible influencing factors of L. principis-rupprechtii seedlings’ natural regeneration were also investigated. The results showed that the spatial distribution patterns of Larix principis-rupprechtii seedlings were concentrated 0–5 m around adult trees when considering the main univariate distribution type of regeneration. There was a positive correlation at a scale of 1.5–4 m between seedlings and adult trees according to bivariate analyses. When the scale was increased, these relationships were no longer significant. Generally, adult trees raised regenerated L. principis-rupprechtii seedlings at a scale of 1.5–4 m. Principal component analysis showed that the understory herb diversity and litter layer had a negative correlation with the number of regenerated seedlings. There was also a weak relationship between regenerated numbers and canopy density. This study demonstrated that the main factors promoting natural regeneration were litter thickness, herb diversity, and the distance between adult trees and regenerated seedlings. Additionally, these findings will provide a basis for the late-stage and practical management of natural regeneration in northern China’s mountain ranges.

Sign in / Sign up

Export Citation Format

Share Document