scholarly journals Assessing Ecological Disturbance in Neotropical Forest Landscapes Using High-Level Diversity and High-Level Functionality: Surprising Outcomes from a Case Study with Spider Assemblages

Land ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 758
Author(s):  
Darinka Costa Gonzalez ◽  
Reinaldo Lucas Cajaiba ◽  
Eduardo Périco ◽  
Wully Barreto da Silva ◽  
Antônio Domingos Brescovite ◽  
...  

Spiders have been increasingly used as environmental and ecological indicators in conservation and ecosystem management. In the Neotropics, there is a shortage of information regarding spiders’ taxonomies and ecological responses to anthropogenic disturbances. To unravel these hitches, we tested the possibility of using high-level diversity and high-level functionality indicators to evaluate spider assemblages’ sensitivity to landscape changes. This approach, if proven informative, might overcome the relevant limitations of taxonomic derived indexes, which are considered time-consuming, cost-demanding and dependent on the (few) expert taxonomists’ availability. Our results highlight the pertinence of both indicators’ responses to the structural changes induced by increasing anthropogenic disturbance, and are associated with reductions in ecosystem complexity, microclimates, and microhabitats. Overall, both indicators were sensitive to structural changes induced by anthropogenic disturbance and should be considered a useful resource for assessing the extent of ecosystems’ disruptions in the Neotropics, and also to guide managers in landscapes’ restoration.

Water ◽  
2021 ◽  
Vol 13 (22) ◽  
pp. 3305
Author(s):  
Li Ji ◽  
Yuan Li ◽  
Guixiang Zhang ◽  
Yonghong Bi

The earth has been reshaped for millennia. The accelerating pace of anthropogenic activities has generated enormous impacts on the water environment. As one of the main drivers of landscape change, anthropogenic disturbance has brought many negative effects on rivers. Studying the relationship between anthropogenic disturbances and river water quality is of significance for regional conservation and ecosystem management, while the relationship remains poorly understood in the current. In this study, we quantified anthropogenic disturbances by introducing the concept of the hemeroby index and evaluated rivers’ water quality in eight sub-watersheds on the Loess Plateau. The results indicated that 37.5% of the sub-watersheds were in Eutrophic status, and 62.5% were in Marginal water quality index. The river water quality was most poor in the southwestern region near the Yellow River with high-level anthropogenic disturbance. A correlation analysis between water quality indicators and hemeroby suggested that anthropogenic disturbance contributed to a significant water quality deterioration trend (p < 0.01). The river water quality was relatively sensitive to the changes of completely disturbed land-use covers, including urban and industrial land. Our findings provide theoretical guidance for regional water resources conservation and ecosystem management in arid areas.


2020 ◽  
Vol 2020 (10) ◽  
pp. 19-33
Author(s):  
Nadiia NOVYTSKA ◽  
◽  
Inna KHLIEBNIKOVA ◽  

The market of tobacco products in Ukraine is one of the most dynamic and competitive. It develops under the influence of certain factors that cause structural changes, therefore, the aim of the article is to conduct a comprehensive analysis of transformation processes in the market of tobacco and their alternatives in Ukraine and identify the factors that cause them. The high level of tax burden and the proliferation of alternative products with a potentially lower risk to human health, including heating tobacco products and e-cigarettes, are key factors in the market’s transformation process. Their presence leads to an increase in illicit turnover of tobacco products, which accounts for 6.37% of the market, and the gradual replacement of cigarettes with alternative products, which account for 12.95%. The presence on the market of products that are not taxed or taxed at lower rates is one of the reasons for the reduction of excise duty revenues. According to the results of 2019, the planned indicators of revenues were not met by 23.5%. Other reasons for non-fulfillment of excise duty revenues include: declining dynamics of the tobacco products market; reduction in the number of smokers; reorientation of «cheap whites» cigarette flows from Ukraine to neighboring countries; tax avoidance. Prospects for further research are identified, namely the need to develop measures for state regulation and optimization of excise duty taxation of tobacco products and their alternatives, taking into account the risks to public health and increasing demand of illegal products.


2020 ◽  
Author(s):  
Viraj kirinda ◽  
Scott Hartley

The self-assembly of foldamers into macrocycles is a simple approach to non-biological higher-order structure. Previous work on the co-assembly of ortho-phenylene foldamers with rod-shaped linkers has shown that folding and self-assembly affect each other; that is, the combination leads to new emergent behavior, such as access to otherwise unfavorable folding states. To this point this relationship has been passive. Here, we demonstrate control of self-assembly by manipulating the foldamers’ conformational energy surfaces. A series of o-phenylene decamers and octamers have been assembled into macrocycles using imine condensation. Product distributions were analyzed by gel-permeation chromatography and molecular geometries extracted from a combination of NMR spectroscopy and computational chemistry. The assembly of o-phenylene decamers functionalized with alkoxy groups or hydrogens gives both [2+2] and [3+3] macrocycles. The mixture results from a subtle balance of entropic and enthalpic effects in these systems: the smaller [2+2] macrocycles are entropically favored but require the oligomer to misfold, whereas a perfectly folded decamer fits well within the larger [3+3] macrocycle that is entropically disfavored. Changing the substituents to fluoro groups, however, shifts assembly quantitatively to the [3+3] macrocycle products, even though the structural changes are well-removed from the functional groups directly participating in bond formation. The electron-withdrawing groups favor folding in these systems by strengthening arene–arene stacking interactions, increasing the enthalpic penalty to misfolding. The architectural changes are substantial even though the chemical perturbation is small: analogous o-phenylene octamers do not fit within macrocycles when perfectly folded, and quantitatively misfold to give small macrocycles regardless of substitution. Taken together, these results represent both a high level of structural control in structurally complex foldamer systems and the demonstration of large-amplitude structural changes as a consequence of a small structural effects.


GIS Business ◽  
2019 ◽  
Vol 14 (6) ◽  
pp. 206-212
Author(s):  
Dr. D. Shoba ◽  
Dr. G. Suganthi

Employees and employers are facing issues in work life balance. It has become a difficult domain now, because the work needs have increased due to an increase in work pressure and complexities in handling the technology. As there are drastic changes in the rules and regulations in the work scenario of the aviation industry, it makes work life balance of employees difficult and set more hurdles. Hence there are many distractions and imbalances in the life of women employees in the aviation industry working across all levels. This work pressure is creating high level of hurdles in maintaining a harmonious job and family life, especially for female aviation employees. Data is collected from 50 female crew members working at Cochin International Airport. The objective of this study is to analyze the work life balance of working females of Cochin International Airport and its influence on their personal and specialized lives. The result of the study shows that the management should frame certain policies which will help employees to have the balance among their personal and expert lives.


2021 ◽  
Vol 13 (6) ◽  
pp. 3246
Author(s):  
Zoe Slattery ◽  
Richard Fenner

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.


Land ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 234
Author(s):  
Dong Han ◽  
Jiajun Qiao ◽  
Qiankun Zhu

Rural-spatial restructuring involves the spatial mapping of the current rural development process. The transformation of land-use morphologies, directly or indirectly, affects the practice of rural restructuring. Analyzing this process in terms of the dominant morphology and recessive morphology is helpful for better grasping the overall picture of rural-spatial restructuring. Accordingly, this paper took Zhulin Town in Central China as a case study area. We propose a method for studying rural-spatial restructuring based on changes in the dominant and recessive morphologies of land use. This process was realized by analyzing the distribution and functional suitability of ecological-production-living (EPL) spaces based on land-use types, data on land-use changes obtained over a 30-year observation period, and in-depth research. We found that examining rural-spatial restructuring by matching the distribution of EPL spaces with their functional suitability can help to avoid the misjudgment of the restructuring mode caused by the consideration of the distribution and structural changes in quantity, facilitating greater understanding of the process of rural-spatial restructuring. Although the distribution and quantitative structure of Zhulin’s EPL spaces have changed to differing degrees, ecological- and agricultural-production spaces still predominate, and their functional suitability has gradually increased. The spatial distribution and functional suitability of Zhulin are generally well matched, with 62.5% of the matched types being high-quality growth, and the positive effect of Zhulin’s spatial restructuring over the past 30 years has been significant. We found that combining changes in EPL spatial area and quantity as well as changes in functional suitability is helpful in better understanding the impact of the national macro-policy shift regarding rural development. Sustaining the positive spatial restructuring of rural space requires the timely adjustment of local actors in accordance with the needs of macroeconomic and social development, and a good rural-governance model is essential.


2020 ◽  
Vol 3 (1) ◽  
pp. 35
Author(s):  
Karolina D. Jasińska ◽  
Mateusz Jackowiak ◽  
Jakub Gryz ◽  
Szymon Bijak ◽  
Katarzyna Szyc ◽  
...  

Human presence or activities are perceived by animals as those associated with predation risk so activity and exploration patterns of animals should be shaped by indices of anthropogenic disturbances. The high level of human disturbances is noticed in big cities. Therefore, the aim of the study was to determine the occurrence of roe deer in Warsaw and its activity in the Warsaw urban forests. We used snow tracking on transect routes (winter seasons 2016, 2017, 2018; 115.1 km in total) to determine roe deer occurrence in four habitats: forests, open areas, parks, and built-up areas. The number of tracks was highest in forests (4.6 tracks/1 km/24 h), followed by open areas, built-up areas, and parks. We used camera traps to determine the activity of roe deer in selected urban forests. We collected 697 observations of roe deer in Warsaw forests in the years 2016–2019 (per 4826 trap-days in total). The peak of roe deer activity was noticed between 4:00 and 5:00 a.m. Animals were least active at 1:00–2:00 p.m. and between 11:00 p.m.–01:00 a.m. Our research showed that roe deer inhabiting the urban area avoided human presence by using well-covered habitats and being active in periods when humans’ disturbances’ level is lower.


2021 ◽  
Vol 43 (1) ◽  
pp. 1-46
Author(s):  
David Sanan ◽  
Yongwang Zhao ◽  
Shang-Wei Lin ◽  
Liu Yang

To make feasible and scalable the verification of large and complex concurrent systems, it is necessary the use of compositional techniques even at the highest abstraction layers. When focusing on the lowest software abstraction layers, such as the implementation or the machine code, the high level of detail of those layers makes the direct verification of properties very difficult and expensive. It is therefore essential to use techniques allowing to simplify the verification on these layers. One technique to tackle this challenge is top-down verification where by means of simulation properties verified on top layers (representing abstract specifications of a system) are propagated down to the lowest layers (that are an implementation of the top layers). There is no need to say that simulation of concurrent systems implies a greater level of complexity, and having compositional techniques to check simulation between layers is also desirable when seeking for both feasibility and scalability of the refinement verification. In this article, we present CSim 2 a (compositional) rely-guarantee-based framework for the top-down verification of complex concurrent systems in the Isabelle/HOL theorem prover. CSim 2 uses CSimpl, a language with a high degree of expressiveness designed for the specification of concurrent programs. Thanks to its expressibility, CSimpl is able to model many of the features found in real world programming languages like exceptions, assertions, and procedures. CSim 2 provides a framework for the verification of rely-guarantee properties to compositionally reason on CSimpl specifications. Focusing on top-down verification, CSim 2 provides a simulation-based framework for the preservation of CSimpl rely-guarantee properties from specifications to implementations. By using the simulation framework, properties proven on the top layers (abstract specifications) are compositionally propagated down to the lowest layers (source or machine code) in each concurrent component of the system. Finally, we show the usability of CSim 2 by running a case study over two CSimpl specifications of an Arinc-653 communication service. In this case study, we prove a complex property on a specification, and we use CSim 2 to preserve the property on lower abstraction layers.


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