Effects of forest fragmentation on neotropical fauna: current research and data availability

1995 ◽  
Vol 3 (2) ◽  
pp. 191-211 ◽  
Author(s):  
Holly L. Offerman ◽  
Virginia H. Dale ◽  
Scott M. Pearson ◽  
Robert V. O'Neill ◽  
Richard O. Bierregaard Jr.
Keyword(s):  
Forest Fragmentation ◽  
Amazon Basin ◽  
Data Availability ◽  
Forest Fragments ◽  
Forest Patches ◽  
Neotropical Fauna ◽  
Using Data ◽  
Spatially Explicit Data ◽  
Biological Dynamics

Tropical deforestation often produces landscapes characterized by isolated patches of forest habitat surrounded by pasture, agriculture, or regrowth vegetation. Both the size and the distribution of these forest patches may influence the long-term persistence of faunal species. There is, therefore, a pressing need to understand faunal responses to patterns of forest fragmentation in tropical systems. The Biological Dynamics of Forest Fragments Project (BDFFP) provides a wealth of autecological information and spatially explicit data describing habitat use and movement of fauna between Amazonian forest fragments. Using data from the BDFFP and other studies in the Amazon Basin, this paper reviews the information available on tropical insects, frogs, birds, primates, and other mammals that can be used to identify and classify species most at risk for extirpation in fragmented forests.Key words: Amazonia, habitat fragmentation, rainforest, fauna, Biological Dynamics of Forest Fragmentation Project.

scholarly journals Are Plant Species’ Richness and Diversity Influenced by Fragmentation at a Microscale?

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Jesús Aguirre-Gutiérrez
Keyword(s):  
Species Richness ◽  
Forest Fragmentation ◽  
Vegetation Type ◽  
Plant Species Richness ◽  
Medium Size ◽  
Negative Effects ◽  
Forest Patches ◽  
Species Richness And Diversity ◽  
Short And Long Term

It is argued that forest fragmentation has negative effects on biodiversity at the short and long term; however, these effects might be dependent on the specific vegetation of the study area and its intrinsic characteristics. The processes leading to fragmentation are very diverse and many of them have anthropogenic causes as logging actions and clearings for agricultural fields. Furthermore, it is thought that scale plays an important role in the expected effects of fragmentation on biodiversity. In this study the effect of forest fragmentation and its impact on the woody plants species, richness and diversity are analysed considering three vegetation types in a poorly studied and difficult access biodiversity hotspot in northern Mexico. The results show that the effects of fragmentation are dependent on the vegetation type and that these are not strongly related to the species richness, and diversity in a microscale (100 m2). Fragmentation effects on biodiversity must be analysed in a broad scale, considering the fragment as a whole. Furthermore, conservation priority should be given to the larger fragments, which could potentially maintain a higher portion of biodiversity. Management should also be focused on increasing the connectivity between these big and medium size forest patches.

scholarly journals Spatial dynamics of deforestation and forest fragmentation (1930–2013) in Eastern Ghats, India

2014 ◽  
Vol XL-8 ◽  
pp. 637-644 ◽  
Author(s):  
C. Sudhakar Reddy ◽  
C. S. Jha ◽  
V. K. Dadhwal
Keyword(s):  
Spatial Analysis ◽  
Forest Fragmentation ◽  
Forest Cover ◽  
Geographical Area ◽  
Eastern Ghats ◽  
Change Analysis ◽  
Forest Patches ◽  
Evergreen Forests ◽  
Topographical Maps

The tropical forests are the most unique ecosystems for their potential economic value. Eastern Ghats, a phytogeographical region of India has rugged hilly terrain distributed in parts of five states, viz. Odisha, Andhra Pradesh, Telangana, Karnataka and Tamil Nadu. The present study is mainly aimed to analyse the trends in deforestation and its role in forest fragmentation of Eastern Ghats. The long term changes in forest cover with its spatial pattern over time has been assessed by analyzing a set of topographical maps and satellite remote sensing datasets. The multi-source and multi-date mapping has been carried out using survey of India topographical maps (1930's), Landsat MSS (1975 and 1985), IRS 1B LISS-I (1995), IRS P6 AWiFS (2005) and Resourcesat-2 AWiFS (2013) satellite images. The classified spatial data for 1930, 1975, 1985, 1995, 2005 and 2013 showed that the forest cover for the mentioned years are 102213 km<sup>2</sup> (45.6 %), 76630 (34.2 %), 73416 km<sup>2</sup> (32.7 %), 71730 km<sup>2</sup> (32 %), 71305 km<sup>2</sup> (31.8 %) and 71186 km<sup>2</sup> (31.7 %) of the geographical area of Eastern Ghats respectively. A spatial statistical analysis of the deforestation rates and forest cover change were carried out based on distinctive time phases, i.e. 1930&ndash;1975, 1975&ndash;1985, 1985&ndash;1995, 1995&ndash;2005 and 2005&ndash;2013. The spatial analysis was carried out first by segmenting the study area into grid cells of 5 km x 5 km for time series assessment and determining spatial changes in forests. The distribution of loss and gain of forest was calculated across six classes i.e. <1 km<sup>2</sup>, 1&ndash;5 km<sup>2</sup>, 5&ndash;10 km<sup>2</sup>, 10&ndash;15 km<sup>2</sup>, 15&ndash;20 km<sup>2</sup> and >20 km<sup>2</sup>. Landscape metrics were used to quantify spatial variability of landscape structure and composition. The results of study on net rate of deforestation was found to be 0.64 during 1935 to 1975, 0.43 during 1975&ndash;1985, 0.23 during 1985&ndash;1995, 0.06 during 1995&ndash;2005 and 0.02 during 2005&ndash;2013. The number of forest patches increased from 2688 (1930) to 13009 (2013). The largest forest patch in 1930 represents area of 41669 km<sup>2</sup> that has reduced to 27800 km<sup>2</sup> by 2013. Thus, it is evident that there is a substantial reduction in the size of the very large forest patches due to deforestation. According to spatial analysis, among the different land use change drivers, agriculture occupies highest area, followed by degradation to scrub and conversion to orchards. The dominant forest type was dry deciduous which comprises 37192 km<sup>2</sup> (52.2 %) of the total forest area of Eastern Ghats, followed by moist deciduous forest (39.2 %) and semievergreen forest (4.8 %) in 2013. The change analysis showed that the large scale negative changes occurred in deciduous forests and semi-evergreen forests compared to wet evergreen forests due to high economic potential and accessibility. This study has quantified the deforestation that has taken place over the last eight decades in the Eastern Ghats. The decline in overall rate of deforestation in recent years indicates increased measures of conservation. The change analysis of deforestation and forest fragmentation provides a decisive component for conservation and helpful in long term management of forests of Eastern Ghats.

scholarly journals Importance of Small Forest Fragments in Agricultural Landscapes for Maintaining Orangutan Metapopulations

2021 ◽  
Vol 4 ◽  
Author(s):  
Marc Ancrenaz ◽  
Felicity Oram ◽  
Nardiyono Nardiyono ◽  
Muhammad Silmi ◽  
Marcie E. M. Jopony ◽  
...  
Keyword(s):  
Oil Palm ◽  
Agricultural Landscapes ◽  
Conservation Strategies ◽  
Forest Fragments ◽  
Multiple Use ◽  
Conservation Areas ◽  
Forest Patches ◽  
Timber Plantations ◽  
Small Forest

Historically, orangutans (Pongo spp.) lived in large contiguous areas of intact rainforest. Today, they are also found in highly modified and fragmented landscapes dominated by oil palm or industrial timber plantations; a situation that calls for new conservation approaches. Here we report signs of orangutan presence in more than 120 small forest fragments of &lt;500 ha in size and isolated in extensive oil palm plantations across Borneo. We confirmed the long-term presence of adult resident females with dependent young in 42% of the fragments assessed by ground survey (n = 50), and the regular sightings of males traveling across the landscape. We argue that orangutans using and living in small isolated forest patches play an essential part in the metapopulation by maintaining gene flow among larger sub-populations distributed across multiple-use landscapes. In some cases, translocations may be necessary when the animals are in imminent danger of being killed and have no other refuge. However, the impacts of removing animals from spatially dispersed metapopulations could inadvertently decrease critical metapopulation functionality necessary for long-term viability. It is clear that orangutans need natural forest to survive. However, our findings show that forest fragments within agricultural landscapes can also complement conservation areas if they are well-distributed, properly connected and managed, and if orangutan killing is prevented. Efforts to better understand the dynamics and the functionality of an orangutan metapopulation in forest-farmland landscape mosaics characteristic of the Anthropocene are urgently needed to design more efficient conservation strategies for the species across its range.

scholarly journals Forest Fragmentation and Connectivity in Virginia Between 2001 and 2011

2018 ◽  
Vol 11 (3) ◽  
pp. 98-119
Author(s):  
Iris E. M. Fynn ◽  
James Campbell
Keyword(s):  
Forest Fragmentation ◽  
Human Activities ◽  
Road Density ◽  
Forest Patches ◽  
Forest Patch ◽  
Topographic Slope ◽  
Annual Population ◽  
Data Source

Abstract With an annual population growth rate currently estimated at about 5 %, Virginia presents an ideal case study for anthropogenic environmental disturbances. Urbanization as a result of increasing human activities has led to fragmentation of many crucial habitats, especially forests. Analysis of the extent to which forest fragmentation and connectivity have occurred in Virginia and corresponding changes associated with these processes, is relevant for conserving forest habitats and the biodiversity that they support. This study applies FRAGSTATS, a software system developed to assess forest fragmentation and connectivity, in combination with ArcGIS, to identify changes in forest patch metrics for Virginia over a ten-year interval (2001, 2006 and 2011) using National Land Cover Datasets (NLCD) maps as data source. Results show that, over ten years, forest patches have significantly declined in size, while the number of forest patches and total length of edge areas have increased over time. Results of this study show that road density in Virginia has no significant effect on forest fragmentation between 2001 and 2011. Analysis using ArcGIS revealed that sizes of core forest areas in Virginia are declining, and that these reductions match local topographic slope. This is because the steepness of the slope of an area dictates the degree of human activities in that area. These results suggest that urban sprawl associated with areas with gentler slopes, may have significant, long-term consequences for natural forest ecosystems and ultimately, biodiversity conservation.

scholarly journals The importance of orangutans in small fragments for maintaining metapopulation dynamics

2020 ◽  
Author(s):  
Marc Ancrenaz ◽  
Felicity Oram ◽  
Nardiyono Nardiyono ◽  
Muhammad Silmi ◽  
Marcie Elene Marcus Jopony ◽  
...  
Keyword(s):  
Oil Palm ◽  
Agricultural Landscapes ◽  
Genetic Connectivity ◽  
Forest Fragments ◽  
Multiple Use ◽  
Conservation Areas ◽  
Forest Patches ◽  
Fragmented Forest ◽  
Ground Survey

Orangutans (Pongo spp.) occur at low densities and therefore large areas are necessary to sustain viable metapopulations, defined here as sets of conspecific units of individuals linked by dispersal. Historically, orangutans lived in large contiguous areas of intact rainforest, but are now increasingly found in agricultural and other landscapes modified by people. Here we collate evidence of orangutans utilizing isolated forest fragments (< 500 ha) within multiple-use landscapes dominated by oil palm monoculture across Borneo. Orangutan signs (i.e. nests) were evident in 76 fragments surveyed by helicopter, and in 50 of 70 additional fragments surveyed on the ground; on average 63 ha in size. This includes presence of adult resident females with dependent young confirmed in 40% of the fragments assessed by ground survey. Our study revealed some resident females are raising offspring in isolated forest patches within mature oil palm stands. This not only confirms that some forest patches can sustain orangutans, but indicates migratory males are capable of reaching these fragments scattered throughout the multiple-use landscape. Therefore, orangutans that use or live in even small isolated forest patches are an essential part of the overall metapopulation by maintaining gene flow between, and genetic connectivity within, populations distributed across larger multiple-use landscapes. Orangutan survival is commonly thought to be low in small, isolated forest patches, and the customary management strategy is to remove (translocate) these individuals and release them in larger forests. In some cases, translocations may be necessary, i.e. in case of fire or when the animals are in eminent danger of being killed and have no other refuge. However, the small amount of data available indicates that mortality rates during and after translocations are high, while the impacts of removing animals from spatially dispersed metapopulations are unknown. Therefore, we argue the current policy of routine translocation rather than conserving the species within human-modified landscapes could inadvertently decrease critical metapopulation functionality necessary for long-term viability. It is clear that orangutans need natural forest to survive, but our findings show that fragmented agricultural landscapes can also serve as complementary conservation areas in addition to fully protected areas if they are well designed with ecological connections, and if orangutan killing can be prevented. To achieve this, we call for a paradigm shift from the traditional large single forest model to one that emphasizes metapopulation functionality in the fragmented forest - human use matrix characteristic of the Anthropocene.

The Association between Audit Manager and Auditor-In-Charge Experience, Effort, and Risk Responsiveness

2018 ◽  
Vol 38 (3) ◽  
pp. 121-147 ◽  
Author(s):  
Christine Contessotto ◽  
W. Robert Knechel ◽  
Robyn A. Moroney
Keyword(s):  
Audit Quality ◽  
Data Availability ◽  
The Core ◽  
Specific Experience ◽  
Primary Core ◽  
Using Data ◽  
Audit Team ◽  
Industry Experience ◽  
Jel Classifications ◽  
Core Role

SUMMARY Audit quality is dependent on the experience and effort of the audit team to identify and respond to client risks (risk responsiveness). Central to each team are the core role holders who plan and execute the audit. While many studies treat the partner as the primary core role holder, the manager and auditor-in-charge (AIC) are also important. Using data for engagements from two midtier firms, we analyze the association between the experience and relative effort of the manager and AIC and risk responsiveness. We find a manager's client-specific experience is associated with risk responsiveness for non-listed clients but find no evidence that the general or industry experience of a manager, or the experience of the AIC, is associated with risk responsiveness. The client-specific experience and relative effort of the partner is associated with risk responsiveness. These results suggests that managers can provide an important, albeit limited, contribution to the audit. JEL Classifications: M2. Data Availability: The data were made available to the researchers on the understanding that they will remain confidential.

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

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.

Clinical impact of myositis-specific autoantibodies on long-term prognosis of juvenile idiopathic inflammatory myopathies: multicentre study

Rheumatology ◽  
2021 ◽  
Author(s):  
Yuichi Yamasaki ◽  
Norimoto Kobayashi ◽  
Shinji Akioka ◽  
Kazuko Yamazaki ◽  
Shunichiro Takezaki ◽  
...  
Keyword(s):  
Matrix Protein ◽  
Multiple Drug ◽  
Idiopathic Inflammatory Myopathies ◽  
Inflammatory Myopathies ◽  
Gamma Subunits ◽  
Specific Autoantibody ◽  
Long Term Prognosis ◽  
Using Data ◽  
Drug Free

Abstract Objectives This study aimed to investigate the clinical characteristics, treatment and prognosis of juvenile idiopathic inflammatory myopathies (JIIM) in Japan for each myositis-specific autoantibody (MSA) profile. Methods A multicentre, retrospective study was conducted using data of patients with JIIM at nine paediatric rheumatology centres in Japan. Patients with MSA profiles, determined by immunoprecipitation using stored serum from the active stage, were included. Results MSA were detected in 85 of 96 cases eligible for the analyses. Over 90% of the patients in this study had one of the following three MSA types: anti-melanoma differentiation-associated protein 5 (MDA5) (n = 31), anti-transcriptional intermediary factor 1 alpha and/or gamma subunits (TIF1γ) (n = 25) and anti-nuclear matrix protein 2 (NXP2) (n = 25) antibodies. Gottron papules and periungual capillary abnormalities were the most common signs of every MSA group in the initial phase. The presence of interstitial lung disease (ILD) was the highest risk factor for patients with anti-MDA5 antibodies. Most patients were administered multiple drug therapies: glucocorticoids and MTX were administered to patients with anti-TIF1γ or anti-NXP2 antibodies. Half of the patients with anti-MDA5 antibodies received more than three medications including i.v. CYC, especially patients with ILD. Patients with anti-MDA5 antibodies were more likely to achieve drug-free remission (29 vs 21%) and less likely to relapse (26 vs 44%) than others. Conclusion Anti-MDA5 antibodies are the most common MSA type in Japan, and patients with this antibody are characterized by ILD at onset, multiple medications including i.v. CYC, drug-free remission, and a lower frequency of relapse. New therapeutic strategies are required for other MSA types.

Increase associated risk of gynaecological cancer due to long-term exposure to high concentration of atmospheric SO2 industrial pollutant

2021 ◽  
pp. 1420326X2110036
Author(s):  
Qian Xu ◽  
Chan Lu ◽  
Rachael Gakii Murithi ◽  
Lanqin Cao
Keyword(s):  
Time Windows ◽  
Air Pollutant ◽  
Gynaecological Cancer ◽  
High Concentration ◽  
The Past ◽  
Short And Long Term ◽  
Using Data ◽  
Air Quality Monitoring Stations ◽  
Control Study

A cohort case–control study was conducted in XiangYa Hospital, Changsha, China, which involved 305 patients and 399 healthy women, from June 2010 to December 2018, to evaluate the association between Chinese women’s short- and long-term exposure to industrial air pollutant, SO2 and gynaecological cancer (GC). We obtained personal and family information from the XiangYa Hospital electronic computer medical records. Using data obtained from the air quality monitoring stations in Changsha, we estimated each woman’s exposure to the industrial air pollutant, sulphur dioxide (SO2), for different time windows, including the past 1, 5, 10 and 15 years before diagnosis of the disease. A multiple logistic regression model was used to assess the association between GC and SO2 exposure. GC was significantly associated with long-term SO2 exposure, with adjusted odds ratio (95% confidence interval) = 1.56 (1.10–2.21) and 1.81 (1.07–3.06) for a per interquartile range increase in the past 10 and 15 years, respectively. Sensitivity analysis showed that different groups reacted in different ways to long-term SO2 exposure. We concluded that long-term exposure to high concentration of industrial pollutant, SO2 is associated with the development of GC. This finding has implications for the prevention and reduction of GC.

scholarly journals Assisting scalable diagnosis automatically via CT images in the combat against COVID-19

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Bohan Liu ◽  
Pan Liu ◽  
Lutao Dai ◽  
Yanlin Yang ◽  
Peng Xie ◽  
...  
Keyword(s):  
Large Scale ◽  
Area Under The Curve ◽  
Independent Set ◽  
Reference Method ◽  
Ct Images ◽  
Loss Of Life ◽  
Case Identification ◽  
Reverse Transcription Pcr ◽  
Using Data

AbstractThe pandemic of Coronavirus Disease 2019 (COVID-19) is causing enormous loss of life globally. Prompt case identification is critical. The reference method is the real-time reverse transcription PCR (RT-PCR) assay, whose limitations may curb its prompt large-scale application. COVID-19 manifests with chest computed tomography (CT) abnormalities, some even before the onset of symptoms. We tested the hypothesis that the application of deep learning (DL) to 3D CT images could help identify COVID-19 infections. Using data from 920 COVID-19 and 1,073 non-COVID-19 pneumonia patients, we developed a modified DenseNet-264 model, COVIDNet, to classify CT images to either class. When tested on an independent set of 233 COVID-19 and 289 non-COVID-19 pneumonia patients, COVIDNet achieved an accuracy rate of 94.3% and an area under the curve of 0.98. As of March 23, 2020, the COVIDNet system had been used 11,966 times with a sensitivity of 91.12% and a specificity of 88.50% in six hospitals with PCR confirmation. Application of DL to CT images may improve both efficiency and capacity of case detection and long-term surveillance.

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