Hydrology and fire regulate edge influence on microclimate in wetland forest patches

The present study investigated whether the flushing distance, the territorial use and the stress hormone physiology of the capercaillie (Tetrao urogallus) were influenced in the winter by the presence of a large number of people engaged in sporting activities. In most cases flushing distances were greater, and higher concentrations of stress hormone were found in the blood serum, in areas having a high intensity of sporting activities than in forest stands relatively undisturbed by tourists. During the ski season capercaillie avoided forest patches within their home ranges where there was a high level of recreational activity. The results lead to the conclusion that intensive winter tourism can be a serious threat to the remaining capercaillie populations in middle Europe. It is recommended that the construction of new recreational facilities and new developments should be avoided in the most important habitats for capercaillie. The important habitats which today already lie in the immediate vicinity of areas intensively used by tourists could clearly receive enhanced status, according to each situation, either as tranquility areas for wildlife where entrance is forbidden or with regulations requiring winter tourists to stay on trails.

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Spatial Analysis of the Drivers, Characteristics, and Effects of Forest Fragmentation

Sustainability ◽

10.3390/su13063246 ◽

2021 ◽

Vol 13 (6) ◽

pp. 3246

Author(s):

Zoe Slattery ◽

Richard Fenner

Keyword(s):

Forest Fragmentation ◽

Forest Fires ◽

Geographical Information ◽

Agricultural Expansion ◽

Forest Patches ◽

Mato Grosso ◽

Remote Imaging ◽

Landscape Characteristics ◽

High Level

Building on the existing literature, this study examines whether specific drivers of forest fragmentation cause particular fragmentation characteristics, and how these characteristics can be linked to their effects on forest-dwelling species. This research uses Landsat remote imaging to examine the changing patterns of forests. It focuses on areas which have undergone a high level of a specific fragmentation driver, in particular either agricultural expansion or commodity-driven deforestation. Seven municipalities in the states of Rondônia and Mato Grosso in Brazil are selected as case study areas, as these states experienced a high level of commodity-driven deforestation and agricultural expansion respectively. Land cover maps of each municipality are created using the Geographical Information System software ArcGIS Spatial Analyst extension. The resulting categorical maps are input into Fragstats fragmentation software to calculate quantifiable fragmentation metrics for each municipality. To determine the effects that these characteristics are likely to cause, this study uses a literature review to determine how species traits affect their responses to forest fragmentation. Results indicate that, in areas that underwent agricultural expansion, the remaining forest patches became more complex in shape with longer edges and lost a large amount of core area. This negatively affects species which are either highly dispersive or specialist to core forest habitat. In areas that underwent commodity-driven deforestation, it was more likely that forest patches would become less aggregated and create disjunct core areas. This negatively affects smaller, sedentary animals which do not naturally travel long distances. This study is significant in that it links individual fragmentation drivers to their landscape characteristics, and in turn uses these to predict effects on species with particular traits. This information will prove useful for forest managers, particularly in the case study municipalities examined in this study, in deciding which species require further protection measures. The methodology could be applied to other drivers of forest fragmentation such as forest fires.

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Structure, Diversity, and Environmental Determinants of High-Latitude Threatened Conifer Forests

Forests ◽

10.3390/f12060775 ◽

2021 ◽

Vol 12 (6) ◽

pp. 775

Author(s):

Carlos Esse ◽

Francisco Correa-Araneda ◽

Cristian Acuña ◽

Rodrigo Santander-Massa ◽

Patricio De Los Ríos-Escalante ◽

...

Keyword(s):

Water Table ◽

Environmental Variables ◽

National Park ◽

High Water ◽

Forest Communities ◽

Competitive Effect ◽

Forest Patches ◽

Last Glaciation ◽

The World ◽

Local Topography

Pilgerodendron uviferum (D. Don) Florin is an endemic, threatened conifer that grows in South America. In the sub-Antarctic territory, one of the most isolated places in the world, some forest patches remain untouched since the last glaciation. In this study, we analyze the tree structure and tree diversity and characterize the environmental conditions where P. uviferum-dominated stands develop within the Magellanic islands in Kawésqar National Park, Chile. An environmental matrix using the databases WorldClim and SoilGrids and local topography variables was used to identify the main environmental variables that explain the P. uviferum-dominated stands. PCA was used to reduce the environmental variables, and PERMANOVA and nMDS were used to evaluate differences among forest communities. The results show that two forest communities are present within the Magellanic islands. Both forest communities share the fact that they can persist over time due to the high water table that limits the competitive effect from other tree species less tolerant to high soil water table and organic matter. Our results contribute to knowledge of the species’ environmental preference and design conservation programs.

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Bird communities in a degraded forest biodiversity hotspot of East Africa

Biodiversity and Conservation ◽

10.1007/s10531-021-02190-y ◽

2021 ◽

Author(s):

Moses Mulwa ◽

Mike Teucher ◽

Werner Ulrich ◽

Jan Christian Habel

Keyword(s):

Tropical Forests ◽

Agricultural Land ◽

Bird Species ◽

Bird Communities ◽

Natural Forest ◽

Tree Plantations ◽

Agricultural Fields ◽

Degraded Forest ◽

Forest Patches ◽

Small Forest

AbstractTropical forests suffer severe habitat destruction. Thus, tropical forests frequently consist today of only a few small remnants that are often embedded within a matrix of agricultural fields and tree plantations. Forest specialist species have experienced severe population declines under these circumstances. We studied bird communities based on census plots set up in a near-natural forest block, as well as degraded forest patches, tree plantations, and agricultural fields, across the Taita Hills in southern Kenya. We classified each bird species according its ecology and behavior. We quantified the land cover and landscape configuration around each census plot. Typical forest species were mainly observed in the near-natural forest block, and to a lower extent in degraded forest patches. Plantations were almost devoid of birds. Bird communities of small forest fragments were more similar to that of agricultural land than the near-natural forest block. Most frugivorous, insectivorous and nectarivorous birds occurred in forest habitats, while granivorous bird species dominated the bird communities of agricultural land. The surrounding landscape had a marginal impact on bird species composition at local sites. Our study showed that the preservation of near-natural cloud forest, including small forest patches, is essential for the conservation of forest-dependent species, and that plantations do not serve as surrogate habitats.

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Auditing Network Embedding: An Edge Influence based Approach

IEEE Transactions on Knowledge and Data Engineering ◽

10.1109/tkde.2021.3056884 ◽

2021 ◽

pp. 1-1

Author(s):

Yaojing Wang ◽

Yuan Yao ◽

Hanghang Tong ◽

Feng Xu ◽

Jian Lu

Keyword(s):

Network Embedding ◽

Edge Influence

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Conserving a geographically isolated Charaxes butterfly in response to habitat fragmentation and invasive alien plants

Koedoe ◽

10.4102/koedoe.v57i1.1297 ◽

2015 ◽

Vol 57 (1) ◽

Author(s):

Casparus J. Crous ◽

James S. Pryke ◽

Michael J. Samways

Keyword(s):

South Africa ◽

Tree Species ◽

Geographical Area ◽

Alien Plants ◽

Western Cape ◽

Forest Patches ◽

Agricultural Matrix ◽

Conservation Implications ◽

Invasive Tree Species ◽

Remnant Forest

In South Africa, much of the forest biome is vulnerable to human-induced disturbance. The forest-dwelling butterfly Charaxes xiphares occidentalis is naturally confined to a small forest region in the south-western Cape, South Africa. Most of the remaining habitat of this species is within a fragmented agricultural matrix. Furthermore, this geographical area is also heavily invaded by alien plants, especially Acacia mearnsii. We investigated how C. x. occidentalis behaviourally responds to different habitat conditions in the landscape. We were particularly interested in touring, patrolling and settling behaviour as a conservation proxy for preference of a certain habitat configuration in this agricultural matrix. Remnant forest patches in the agricultural matrix showed fewer behavioural incidents than in a reference protected area. Moreover, dense stands of A. mearnsii negatively influenced the incidence and settling pattern of this butterfly across the landscape, with fewer tree settlings associated with more heavily invaded forest patches. This settling pattern was predominantly seen in female butterflies. We also identified specific trees that were settled upon for longer periods by C. x. occidentalis. Distance to a neighbouring patch and patch size influenced behavioural incidences, suggesting that further patch degradation and isolation could be detrimental to this butterfly. Conservation implications: We highlight the importance of clearing invasive tree species from vulnerable forest ecosystems and identify key tree species to consider in habitat conservation and rehabilitation programmes for this butterfly. We also suggest retaining as much intact natural forest as possible. This information should be integrated in local biodiversity management plans.

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Tree Diversity and Their Regeneration in the Sacred Groves of Virajpet, Central Western Ghats, India

Notulae Scientia Biologicae ◽

10.15835/nsb839833 ◽

2016 ◽

Vol 8 (3) ◽

pp. 360-369

Author(s):

Devi A.G. PRASAD ◽

Shwetha BHARATHI

Keyword(s):

Tree Species ◽

Western Ghats ◽

Basal Area ◽

Sacred Groves ◽

Forest Patches ◽

Tree Species Composition ◽

Rich Diversity ◽

Central Western Ghats ◽

Undisturbed Forest ◽

The Rich

Sacred groves are one of the finest examples of informal way of conserving the forest wealth. Baseline data collection of their diversity, distribution and regeneration capacity becomes necessary for the management and conservation of these undisturbed forest patches. In this context, the present investigation was carried out using random quadrat method in the sacred groves of Virajpet, Karnataka, India. A total of 132 tree species belonging to 113 genera and 45 families were identified within five sacred groves. Higher basal area (51.73-85.65 m2/ha) and tree density (453.33-515.9 individuals/ha) were observed as compared to other forests of Western Ghats region. The present investigation has revealed a healthy regeneration of tree species. Seedling and sapling composition differed to some extent from the mature tree species composition which could be used in predicting the future possibilities. Protection and conservation of such sacred groves should be of interest, for better regeneration of the rich diversity they harbour.

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Nonlinear Corrections for Edge Bending of Shells

Journal of Applied Mechanics ◽

10.1115/1.3153803 ◽

1980 ◽

Vol 47 (4) ◽

pp. 861-865 ◽

Cited By ~ 6

Author(s):

G. V. Ranjan ◽

C. R. Steele

Keyword(s):

Differential Equations ◽

Spherical Shell ◽

Asymptotic Expansions ◽

Axial Displacement ◽

Exponential Functions ◽

Spherical Cap ◽

Influence Coefficients ◽

Edge Loading ◽

General Geometry ◽

Edge Influence

Asymptotic expansions for self-equilibrating edge loading are derived in terms of exponential functions, from which formulas for the stiffness and flexibility edge influence coefficients are obtained, which include the quadratic nonlinear terms. The flexibility coefficients agree with those previously obtained by Van Dyke for the pressurized spherical shell and provide the generalization to general geometry and loading. In addition, the axial displacement is obtained. The nonlinear terms in the differential equations can be identified as “prestress” and “quadratic rotation.” To assess the importance of the latter, the problem of a pressurized spherical cap with roller supported edges is considered. Results show that whether the rotation at the edge is constrained or not, the quadratic rotation terms do not have a large effect on the axial displacement. The effect will be large for problems with small membrane stresses.

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Amphibians found in the Amazonian Savanna of the Rio Curiaú Environmental Protection Area in Amapá, Brazil

Biota Neotropica ◽

10.1590/1676-0611-bn-2016-0252 ◽

2017 ◽

Vol 17 (2) ◽

Cited By ~ 2

Author(s):

Janaina Reis Ferreira Lima ◽

Jucivaldo Dias Lima ◽

Soraia Dias Lima ◽

Raullyan Borja Lima Silva ◽

Gilda Vasconcellos de Andrade

Keyword(s):

Environmental Protection ◽

Common Species ◽

Temporary Ponds ◽

Sampling Effort ◽

Forest Patches ◽

Amphibian Species ◽

Environmental Protection Area ◽

Protection Area ◽

Northern Brazil ◽

Few Data

Abstract Amphibian research has grown steadily in recent years in the Amazon region, especially in the Brazilian states of Amazonas, Pará, Rondônia, and Amapá, and neighboring areas of the Guiana Shield. Even so, few data are available for the Amazonian savannas of Brazil. To contribute to the understanding of the diversity of the amphibians of these savannas, we surveyed 15 temporary ponds, six located in open areas, seven on the edge of savanna forest, and two within the forest, in the savanna of the Rio Curiaú Environmental Protection Area (EPA) in Macapá, in the state of Amapá, northern Brazil. Sampling occurred from May 2013 to August 2014 during periods when the ponds contained water. Amphibians were sampled through visual and auditory surveys conducted during both the day- and the nighttime periods on seven days each month over a total of 84 days. A total of 1574 individuals belonging to four families, 12 genera, and 28 species were recorded during the surveys. The cumulative species curve reached the asymptote, indicating that sampling effort was adequate. The number of species was 25% higher than that reported in other studies in Amazonian savannas. Twelve species were recorded for the first time in the savanna of Amapá. Lysapsus boliviana was the most common species (n = 332 of the individuals recorded). The greatest amphibian species richness found in the Rio Curiaú EPA was associated with the savanna mosaic, forest patches, lowland swamp, and temporary ponds. The results of this study contribute to the understanding of the diversity of amphibian species in the Guianan area of endemism in northern Brazil, and also the Amazonian savannas.

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