scholarly journals Local Fractal Connections to Characterize the Spatial Processes of Deforestation in the Ecuadorian Amazon

Entropy ◽  
2021 ◽  
Vol 23 (6) ◽  
pp. 748
Author(s):  
Andrea Urgilez-Clavijo ◽  
David Andrés Rivas-Tabares ◽  
Juan José Martín-Sotoca ◽  
Ana María Tarquis Alfonso
Keyword(s):  
Fractal Dimension ◽  
Biosphere Reserve ◽  
Primary Forest ◽  
Forest Loss ◽  
Spatial Processes ◽  
Land Transformation ◽  
Land Fragmentation ◽  
Spatial And Temporal Scales ◽  
Segmentation Methods ◽  
Ecuadorian Amazon

Deforestation by human activities is a common issue in Amazonian countries. This occurs at different spatial and temporal scales causing primary forest loss and land fragmentation issues. During the deforestation process as the forest loses connectivity, the deforested patches create new intricate connections, which in turn create complex networks. In this study, we analyzed the local connected fractal dimension (LCFD) of the deforestation process in the Sumaco Biosphere Reserve (SBR) with two segmentation methods, —CA-wavelet and K-means—to categorize the complexity of deforested patches’ connections and then relate these with the spatial processes. The results showed an agreement with both methods, in which LCFD values below 1 corresponded to isolated patches with simple shapes and those above 1 signified more complex and connected patches. From CA-wavelet a threshold of 1.57 was detected allowing us to identify and discern low and high land transformation, while the threshold for K-means was 1.61. Both values represent the region from which deforestation performs local aggressive expansion networks. The thresholds were used to map the LCFD in which all spatial processes were visually detected. However, the threshold of 1.6 ± 0.03 was more effective in discerning high land transformation. such as shrinkage and attrition, in the deforestation process in the SBR.

Multiscale local connections of deforestation process in the Ecuadorian Amazon

2021 ◽  
Author(s):  
Andrea Urgilez-Clavijo ◽  
David Rivas-Tabares ◽  
Juan José Martín-Sotoca ◽  
Ana M. Tarquis
Keyword(s):  
Biosphere Reserve ◽  
Fractal Dimensions ◽  
Spatial Relations ◽  
Relevant Information ◽  
Forest Loss ◽  
Agricultural Expansion ◽  
Observation Data ◽  
Agricultural Insurance ◽  
Novel Approach ◽  
Ecuadorian Amazon

<p>The deforestation process is nowadays recognized as a global concern due to a variety of environmental issues associated with forest loss. Exacerbated deforestation rates in basins such as the Amazon river basin is contributing tremendously to environmental global degradation and climate change. Previous studies regarding the deforestation process suggest that soils and forest loss are correlated exhibiting non-linear and multi-scale behaviors. Based on this, we conduct a novel approach based on image analysis of the deforestation process to improve the understanding of local connections of this process in a Biosphere reserve in the Ecuadorian Amazon. Understanding the connections between deforested patches and how they are strengthening the deforestation process could provide new features for understanding forest loss associated with agricultural expansion. Thus, these map features can be used for modeling purposes of agricultural expansion and forest loss impact. This work is based on the assessment of cumulative images of deforestation in the <em>Sumaco</em> biosphere reserve in the Ecuadorian Amazon from 1985 to 2018. For this, we rigorously sampling every deforested pixel of the images through the moving window technique to calculate the fractal dimension of the connected pixels at different scales. Once fractal dimensions are calculated, we classify these values to mapping the existing relations. The mapping results show different complexity levels in local connections of the deforestation process. These spatial relations can improve the understanding of deforestation patterns and provide relevant information for decision-making to conservation programs.</p> <p><strong>Acknowledgements:</strong> The authors acknowledge the support of Project No. PGC2018-093854-B-<br />I00 of the Ministerio de Ciencia, Innovación y Universidades of Spain and the financial support from Boosting Agricultural Insurance based on Earth Observation data - BEACON project under agreement Nº 821964,funded under H2020EU, DT-SPACE-01-EO-2018-2020.</p>

scholarly journals Responses of Bat Communities (Mammalia: Chiroptera) to Forest Loss and Habitat Conversion in Southern Cameroon

2021 ◽  
Vol 14 ◽  
pp. 194008292110103
Author(s):  
Patrick Jules Atagana ◽  
Eric Moïse Bakwo Fils ◽  
Sevilor Kekeunou
Keyword(s):  
Secondary Forest ◽  
Biosphere Reserve ◽  
Abundant Species ◽  
Primary Forest ◽  
Habitat Types ◽  
Habitat Transformation ◽  
Significant Difference ◽  
Southern Cameroon ◽  
Habitat Conversion ◽  
Species Specific

We aimed to assess how bats are affected by habitat transformation by comparing bat assemblages in four habitat types: primary forest, secondary forest, cocoa plantations and human habitations in the Dja Biosphere Reserve of southern Cameroon. Bats were sampled in the four habitat types using mist nets. During 126 nights, a total of 413 bats were captured, belonging to four families, 16 genera and 24 species. Ninety three individuals (17 species) were captured in the primary forest, followed by plantations (105 individuals, 14 species), human habitations (159 individuals, 10 species), and secondary forest (55 individuals, eight species). Megaloglossus woermanni was recorded in all the four habitats, and was the most abundant species (105 individuals). The analysis of bat assemblage between habitat types showed a statistically significant difference in species composition. The distribution of the six most abundant species ( Epomops franqueti, Megaloglossus woermanni, Rousettus aegyptiacus, Dohyrina cyclops, Hipposideros cf. caffer and Hipposideros cf. ruber) was influenced by habitat types. Our results suggest that the decrease in species richness observed in disturbed habitats may be due to habitat perturbations of primary forest habitats. Therefore, it is important to examine the effects of habitat conversion at species level, as responses are often species-specific.

scholarly journals Potensi Jenis Dipterocarpaceae di Hutan Produksi Cagar Biosfer Pulau Siberut, Sumatera Barat

2016 ◽  
Vol 16 (1) ◽  
pp. 64
Author(s):  
Endro Subandriono ◽  
M. Bismark ◽  
N. M. Heriyanto
Keyword(s):  
Similarity Index ◽  
Biosphere Reserve ◽  
Seedling Stage ◽  
Primary Forest ◽  
Sample Plot ◽  
Index Value

<p>The study of<br />Dipterocarpaceae was done in November 2007 in Siberut<br />Biosphere Reserve. This study conducted on threes sample plot<br />of 0.75 ha in primery forest, logged over area (LOA) &lt;1 year<br />and LOA 5 years. The result showed there were three species<br />of Dipterocarpaceae: Dipterocarpus elongatus Korth., Shorea<br />johorensis Foxw. and Hopea mangarawan Miq. The density of<br />tree and pole in primary forest were about 24 individual/ha and<br />13.34 individual/ha, there were 9.3 individual/ha and 4<br />individual/ha in LOA &lt;1 year, than this density were 8<br />individual/ha and 5.34 individual/ha in LOA 5 years. For<br />sapling and seedling, these densities were about 29<br />individual/ha and 5.417 individual/ha in primary forest, 5<br />individual/ha and 3.750 individual/ha in LOA &lt;1 year, 89<br />individual/ha and 883 individual/ha in LOA 5 years.<br />Community couple between primary forest and LOA wich has<br />similarity index value more than 50%; at tree stage, it was<br />68,83% comparing primary forest and LOA &lt;1 year; at pole<br />stage it was 62.62% comparing primary forest and LOA 5<br />years; at sapling stage, there were 53.29% and 66,27%<br />comparing with LOA &lt;1 year and LOA 5 years; at seedling<br />stage it was 88.66% compared to primary forest and LOA &lt;1<br />year. Similarity index between LOA &lt;1 year with LOA 5<br />years, there were 60.26% for tree stage, 90.05% for pole stage<br />and 51.13% for seedling stage.</p>

scholarly journals Influence of Landscape Structure on Toucans and Parrots in the Fragmented Landscape of Los Tuxtlas, Mexico

2021 ◽  
Vol 14 ◽  
pp. 194008292110499
Author(s):  
Marisela Martínez-Ruiz ◽  
Miguel A. De Labra-Hernández ◽  
Fernando César Gonçalves Bonfim ◽  
Eliana Cazetta
Keyword(s):  
Landscape Structure ◽  
Forest Cover ◽  
Bird Species ◽  
Edge Density ◽  
Primary Forest ◽  
Forest Loss ◽  
Fragmented Landscape ◽  
Los Tuxtlas ◽  
Habitat Amount ◽  
Positive Effects

Background and Research Aims: Habitat amount plays an important role in determining the presence and abundance of bird species in modified landscapes, whereas habitat fragmentation has shown little effects. Toucans (Ramphastidae) and parrots (Psittacidae) are large-bodied primary consumers and among the most representative birds in Neotropical forests. They are highly sensitive to habitat loss; nevertheless, their response to fragmentation has been poorly assessed leading to contradictory results. Here, we evaluate the influence of landscape structure on toucans and parrots in the tropical forest of Los Tuxtlas, Mexico. Methods: We censused birds in 12 landscapes of Los Tuxtlas and used a multi-scale landscape approach to assess the influence of landscape composition and configuration on the number of individuals of toucans and parrots. Results: We found that the most important and positive predictor of toucans and parrots was the amount of primary forest cover in the landscape. Forest fragmentation had positive effects on the number of toucan individuals, whereas parrots had negative responses to patch density but positive responses to edge density in the landscape. Conclusion: Our results suggest that primary forest loss is the main threat for toucans and parrots in Los Tuxtlas. Implications for conservation: Future conservation and land management must consider the protection of large and small remnants of primary forest and avoid additional forest loss in order to preserve toucan and parrots and their functional roles in human-modified Neotropical landscapes.

scholarly journals Ongoing primary forest loss in Brazil, Democratic Republic of the Congo, and Indonesia

2018 ◽  
Vol 13 (7) ◽  
pp. 074028 ◽  
Author(s):  
Svetlana Turubanova ◽  
Peter V Potapov ◽  
Alexandra Tyukavina ◽  
Matthew C Hansen
Keyword(s):  
Democratic Republic ◽  
Primary Forest ◽  
Forest Loss ◽  
Republic Of The Congo

scholarly journals Tracking changes and preventing loss in critical tiger habitat

2016 ◽  
Vol 2 (4) ◽  
pp. e1501675 ◽  
Author(s):  
Anup R. Joshi ◽  
Eric Dinerstein ◽  
Eric Wikramanayake ◽  
Michael L. Anderson ◽  
David Olson ◽  
...  
Keyword(s):  
Habitat Loss ◽  
Forest Monitoring ◽  
Forest Loss ◽  
Source Population ◽  
Spatial And Temporal Scales ◽  
The Status ◽  
Tiger Population ◽  
Monitoring Technologies ◽  
New Applications ◽  
Global Population

The global population of wild tigers remains dangerously low at fewer than 3500 individuals. Habitat loss, along with poaching, can undermine the international target recovery of doubling the number of wild tigers by 2022. Using a new satellite-based monitoring system, we analyzed 14 years of forest loss data within the 76 landscapes (ranging from 278 to 269,983 km2) that have been prioritized for conservation of wild tigers. Our analysis provides an update of the status of tiger habitat and describes new applications of technology to detect precisely where forest loss is occurring in order to curb future habitat loss. Across the 76 landscapes, forest loss was far less than anticipated (79,597 ± 22,629 km2, 7.7% of remaining habitat) over the 14-year study period (2001–2014). Habitat loss was unevenly distributed within a subset of 29 landscapes deemed most critical for doubling wild tiger populations: 19 showed little change (1.5%), whereas 10 accounted for more than 98% (57,392 ± 16,316 km2) of habitat loss. Habitat loss in source population sites within 76 landscapes ranged from no loss to 435 ± 124 km2 (x¯=24km2, SD = 89, total = 1676 ± 476 km2). Doubling the tiger population by 2022 requires moving beyond tracking annual changes in habitat. We highlight near–real-time forest monitoring technologies that provide alerts of forest loss at relevant spatial and temporal scales to prevent further erosion.

scholarly journals Examining Land Use/Land Cover Change and Its Prediction Based on a Multilayer Perceptron Markov Approach in the Luki Biosphere Reserve, Democratic Republic of Congo

2021 ◽  
Vol 13 (12) ◽  
pp. 6898
Author(s):  
Opelele Omeno Michel ◽  
Yu Ying ◽  
Fan Wenyi ◽  
Chen Chen ◽  
Kachaka Sudi Kaiko
Keyword(s):  
Land Use ◽  
Land Cover ◽  
Land Cover Change ◽  
Multilayer Perceptron ◽  
Secondary Forest ◽  
Biosphere Reserve ◽  
Primary Forest ◽  
Fallow Land ◽  
Land Use Land Cover ◽  
Landscape Metric

Villages within the Luki Biosphere Reserve and the surrounding cities have undergone rapid demographic growth and urbanization that have impacted the reserve’s natural landscape. However, no study has focused on the spatiotemporal analysis of its land use/land cover. The present research aims at providing a comprehensive analysis of land use/land cover change in the Luki Biosphere Reserve from the year 1987 to 2020, and to predict its future change for the year 2038. Landsat images were classified in order to provide land use/land cover maps for the years 1987, 2002, 2017 and 2020. Based on these maps, change detection, gradient direction, and landscape metric analyses were performed. In addition, land use/land cover change prediction was carried out using the Multilayer Perceptron Markov model. The results revealed significant land use/land cover changes in the Luki Biosphere Reserve during the study period. Indeed, tremendous changes in the primary forest, which lost around 17.8% of its total area, were noted. Other classes, notably savannah, secondary forest, built-up area, fallow land and fields had gained 79.35, 1150.36, 67.63, 3852.12 hectares, respectively. Based on the landscape metric analysis, it was revealed that built-up areas and fallow land and fields experienced an aggregation trend, while other classes showed disaggregation and fragmentation trends. Analysis further revealed that village expansion has significantly affected the process of land use/land cover change in the Luki Biosphere Reserve. However, the prediction results revealed that the primary forest will continue to increase while built-up area, fallow land and fields will follow a trend similar to a previous one. As for secondary forest and savannah, the forecast revealed a decrease of the extent during the period extending from 2020 to 2038. The present findings will benefit the decision makers, particularly in the sustainable natural resources management of the Luki Biosphere Reserve.

scholarly journals Fractal dimension of EEG signal senses complexity of fractal animations

2021 ◽  
Author(s):  
Sarshar Dorosti ◽  
Reza Khosrowabadi
Keyword(s):  
Fractal Dimension ◽  
Information Processing ◽  
Visual Stimuli ◽  
Fractal Dimensions ◽  
Neural Mechanism ◽  
Eeg Signal ◽  
Eeg Signals ◽  
Spatial And Temporal Scales ◽  
Box Counting Method ◽  
The Brain

AbstractWe are surrounded with many fractal and self-similar patterns which has been area of many researches in the recent years. We can perceive self-similarities in various spatial and temporal scales; however, the underlying neural mechanism needs to be well understood. In this study, we hypothesized that complexity of visual stimuli directly influence complexity of information processing in the brain. Therefore, changes in fractal pattern of EEG signal must follow change in fractal dimension of animation. To investigate this hypothesis, we recorded EEG signal of fifteen healthy participants while they were exposed to several 2D fractal animations. Fractal dimension of each frame of the animation was estimated by box counting method. Subsequently, fractal dimensions of 32 EEG channels were estimated in a frequency specific manner. Then, association between pattern of fractal dimensions of the animations and pattern of fractal dimensions of EEG signals were calculated using the Pearson’s correlation algorithm. The results indicated that fractal animation complexity is mainly sensed by changes in fractal dimension of EEG signals at the centro-parietal and parietal regions. It may indicate that when the complexity of visual stimuli increases the mechanism of information processing in the brain also enhances its complexity to better attend and comprehend the stimuli.

scholarly journals Reliability of Using Retinal Vascular Fractal Dimension as a Biomarker in the Diabetic Retinopathy Detection

2016 ◽  
Vol 2016 ◽  
pp. 1-13 ◽  
Author(s):  
Fan Huang ◽  
Behdad Dashtbozorg ◽  
Jiong Zhang ◽  
Erik Bekkers ◽  
Samaneh Abbasi-Sureshjani ◽  
...  
Keyword(s):  
Fractal Dimension ◽  
Automatic Segmentation ◽  
Clinical Applications ◽  
Regions Of Interest ◽  
Branching Pattern ◽  
Pattern Complexity ◽  
Potential Biomarker ◽  
Segmentation Methods ◽  
Relative Errors ◽  
The Stability

The retinal fractal dimension (FD) is a measure of vasculature branching pattern complexity. FD has been considered as a potential biomarker for the detection of several diseases like diabetes and hypertension. However, conflicting findings were found in the reported literature regarding the association between this biomarker and diseases. In this paper, we examine the stability of the FD measurement with respect to (1) different vessel annotations obtained from human observers, (2) automatic segmentation methods, (3) various regions of interest, (4) accuracy of vessel segmentation methods, and (5) different imaging modalities. Our results demonstrate that the relative errors for the measurement of FD are significant and FD varies considerably according to the image quality, modality, and the technique used for measuring it. Automated and semiautomated methods for the measurement of FD are not stable enough, which makes FD a deceptive biomarker in quantitative clinical applications.

scholarly journals Soil Hydraulic Properties of Plinthosol in the Middle Yangtze River Basin, Southern China

Water ◽  
2020 ◽  
Vol 12 (6) ◽  
pp. 1783
Author(s):  
Yongwu Wang ◽  
Tieniu Wu ◽  
Jianwu Huang ◽  
Pei Tian ◽  
Hailin Zhang ◽  
...  
Keyword(s):  
Fractal Dimension ◽  
River Basin ◽  
Water Conservation ◽  
Yangtze River ◽  
Hydraulic Properties ◽  
Southern China ◽  
Yangtze River Basin ◽  
Soil Hydraulic Properties ◽  
Spatial And Temporal Scales ◽  
Soil Hydraulic

Soil hydraulic properties are ecologically important in arranging vegetation types at various spatial and temporal scales. However, there is still a lack of detailed understanding of the basic parameters of plinthosol in the Middle Yangtze River basin. This paper focuses on the soil hydraulic properties of three plinthosol profiles at Yueyang (YE), Wuhan (WH), and Jiujiang (JU) and tries to reveal the origin of plinthosol and the relationship among the soil hydraulic parameters. Discriminant analysis indicated that the plinthosol in the JU profile was of aeolian origin, while that in the WH and YE profiles was of alluvial origin; soil hydraulic properties varied greatly among these profiles. The proportion of macro-aggregates (>0.25 mm, weight%) in the JU profile (88.28%) was significantly higher than that in the WH (73.63%) and YE (57.77%) profiles; the water holding capacity and saturated hydraulic conductivity of JU plinthosol was also higher than that of WH and YE plinthosol; the fact that Dr and Di of the JU profile are lower than those of the YE and WH profiles illustrates the stability of JU plinthosol is better than that of YE and WH plinthosol, which is consistent with the fractal dimension of aggregates. The disintegration curves of white vein and red matrix demonstrated a large discrepancy in the JU profile, but these curves showed a similar trend in the WH and YE profiles. The differences in hydraulic properties might be ascribed to the origin of plinthosol, and the results of the fractal dimension also confirmed this conclusion. This study might provide a better understanding of the soil physical properties of plinthosol and shed light on the soil and water conservation measures in the Middle Yangtze River basin.

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