scholarly journals Simulated encounters with a novel competitor reveal the potential for maladaptive behavioural responses to invasive species

2021 ◽  
Author(s):  
T. Champneys ◽  
K. Ferry ◽  
S. Tomkinson ◽  
M. J. Genner ◽  
C. C. Ioannou
Keyword(s):  
Native Species ◽  
Early Stage ◽  
Interspecific Interactions ◽  
Behavioural Response ◽  
Negative Consequences ◽  
Transparent Plastic ◽  
Behavioural Responses ◽  
Individual Fitness ◽  
Set Up ◽  
The Impact

AbstractDuring the early stage of biological invasions, interactions occur between native and non-native species that do not share an evolutionary history. This can result in ecological naïveté, causing native species to exhibit maladaptive behavioural responses to novel enemies, leading to negative consequences for individual fitness and ecosystem function. The behavioural response of native to non-native species during novel encounters can determine the impact of non-native species, and restrict or facilitate their establishment. In this study we simulated novel encounters between a widespread invasive fish species, the Nile tilapia (Oreochromis niloticus), and a threatened native Manyara tilapia (Oreochromis amphimelas). In the first experiment single adult O. niloticus were presented with a stimulus chamber (a transparent plastic cylinder) which was empty during control trials and contained a pair of juvenile O. amphimelas in stimulus trials. In the second experiment, the reciprocal set up was used, with pairs of juvenile O. amphimelas as the focal species and adult O. niloticus as the stimulus. Both species approached the stimulus chamber more readily during stimulus trials, a behavioural response which would increase the prevalence of interspecific interactions in situ. This included physical aggression, observed from the competitively dominant O. niloticus towards O. amphimelas. Despite an initial lack of fear shown by O. amphimelas, close inspection of the stimulus chamber often resulted in an energetically costly dart response. Under field conditions we predict that naïve native individuals may readily approach O. niloticus, increasing the likelihood of interactions and exacerbating widely reported negative outcomes.

scholarly journals The Impact of the Regulatory Reform Process on the R&D Investment of European Electricity Utilities

2014 ◽  
Vol 13 (1) ◽  
Author(s):  
Stephan Schmitt ◽  
Denes Kucsera
Keyword(s):  
Regulatory Reform ◽  
Reform Process ◽  
Negative Consequences ◽  
Data Set ◽  
Ownership Unbundling ◽  
Framework Conditions ◽  
Set Up ◽  
The Impact ◽  
Electricity Utilities ◽  
D Investment

AbstractThe aim of this paper is to provide deeper insights into the impact of regulatory reforms and privatization on the R&D spending of electricity utilities. Building on a novel panel data set including the biggest European utilities from eight EU countries over a period from 1985 to 2010, we find that the overall influence of the European regulatory reform process on R&D investment is ambiguous. The empirical evidence indicates that the approaching liberalization process, i.e., nearing competition, has a dampening effect on R&D spending. Utilities reduce their expenses due to increased uncertainties and additional risks. However, once the market and regulatory framework conditions have been set up and firms have become used to the new situation, higher levels of competition positively influence R&D and former incumbents invest more in order to “escape” from the competition. Moreover, we find no indication that (ownership) unbundling and incentive regulation directly affect the research expenditures of the utilities. In contrast, the privatization of utilities seems to have strong negative consequences for their amount of R&D spending.

scholarly journals Determination of Factors and Indicators of Efficient Port Functioning

2021 ◽  
pp. 105-109
Author(s):  
M. Makarenko ◽  
◽  
I. Barskiy ◽  
V. Popov ◽  
◽  
...  
Keyword(s):  
Comparative Analysis ◽  
Performance Indicators ◽  
Negative Consequences ◽  
Unified Approach ◽  
Cross Sectional ◽  
Theoretical Approaches ◽  
Port Efficiency ◽  
Set Up ◽  
Clear Idea ◽  
The Impact

The article emphasizes the lack of a systematic and unified approach to measuring the performance of ports with different properties. The analysis of practical and theoretical approaches and the comparative analysis of indicators of efficiency of port are carried out. Measuring efficiency plays a significant role in assessing production in its current and future state. With the appropriate performance measurement, the system in the organization can be set up to move in the desired direction by analyzing behavioral responses and understanding the impact of different performance indicators on port performance. However, incorrectly defined performance indicators will lead the organization in the wrong direction and cause unforeseen negative consequences. Port efficiency can have a major impact on the region's economic growth, as ports connect maritime transport and inland transport. They are also important suppliers for ships, cargo and inland transport. Port performance analysis gives operators a clear idea of how much port resources are being used and helps them compare their strengths and weaknesses. Measuring port efficiency improves port development and maintains its competitiveness in an increasingly competitive commercial environment. Therefore, it is important to first conduct a comprehensive study to determine the performance of the port, relevant to the activities of ships, cargo and terminals. By assessing the efficiency of ports using certain indicators, you can get an idea of comparing their efficiency, even internationally. A review of practical and theoretical approaches to the comparative analysis of port efficiency indicators over the past three decades and summarized the main differences in these studies found the lack of a systematic and unified approach to measuring the performance of ports with different properties. Recent studies have aimed to analyze the performance of port terminals, as they are the most important component of ports, operations for the transfer of berths and court operations in the terminals fundamentally determine the efficiency of the port. Port bandwidth is one of the most widely used indicators of port efficiency. Productivity growth is seen as direct evidence of port activity. One of the most important aspects of measuring seaport efficiency is performance, and the popular database analysis (DEA) method is commonly used to evaluate it. There are several other models used for cross-sectional and panel data, such as software. To assess port efficiency, this study examines the analysis of the DEA and FDH database through its ability to analyze multiple outputs and inputs simultaneously.

Implications of Adult-Use Cannabis Legalization from the Perspective of Adolescent Health

2021 ◽  
Vol 11 ◽  
Author(s):  
Mark D. Elliott ◽  
Bryon Adinoffz
Keyword(s):  
Adolescent Health ◽  
Early Stage ◽  
The United States ◽  
Cannabis Use ◽  
Negative Consequences ◽  
School Suspensions ◽  
Criminal Penalties ◽  
The Impact ◽  
Perceived Harm ◽  
Out Of School

Background: Adult-use cannabis legalization is being increasingly embraced by various jurisdictions in the United States (US) and internationally. As adolescents are particularly vulnerable to the negative consequences of cannabis, it is essential to ensure that the effects of adult-use legalization are minimized. Objectives: This review aimed to synthesize the extant literature exploring the impact of adult-use legalization on adolescents and provide recommendations for future action. We focused on the following domains: 1) prevalence of use, 2) high-frequency use, 3) perceived harm, 4) perceived availability, 5) modes of use, 6) potency, 7) mental health and medical outcomes, and 8) legal consequences. Methods: Narrative review is focused on adult-use legalization in the US. Results: Adolescent cannabis use prevalence in US legal (as well as illegal) states has remained essentially stable since the advent of adult-use legalization. Criminal penalties for adolescents have not decreased in legal states and maybe increasing; out-of-school suspensions for cannabis use may also be increasing. It is uncertain whether reported decreases in national rates of perceived harm and availability and increases in cannabis frequency and potency of use in adolescents differ between legal and illegal states. The impact of legalization on adolescent health outcomes remains uncertain. Conclusion: At this early stage of adult-use legalization, we recommend that jurisdictions implement real-time, detailed monitoring to assess adolescent outcomes. In addition, both criminal penalties and out-of-school suspensions for cannabis infractions should be minimized.

scholarly journals Invasion of alien plant species and their impact on different ecosystems of Panchase Area, Nepal

2017 ◽  
Vol 27 (1) ◽  
pp. 31-42 ◽  
Author(s):  
S. Baral ◽  
A Adhikari ◽  
R. Khanal ◽  
Y. Malla ◽  
R. Kunwar ◽  
...  
Keyword(s):  
Plant Species ◽  
Native Species ◽  
Household Survey ◽  
Gis Mapping ◽  
Negative Consequences ◽  
Agricultural Lands ◽  
Alien Plant Species ◽  
Alien Plant ◽  
Invasive Alien Plant ◽  
The Impact

The aggressiveness of invasive alien plant species has been amidst the changing climate, which has necessitated further research in this area. The impact of invasive alien plant species in the Panchase area of Nepal was assessed through the forest resource assessment and other methodologies such as, household survey, group discussion, direct field observation, participatory cluster mapping, quadrat sampling, laboratory analysis, and GIS mapping. A total of nine major invasive species, in which Ageratum houstonianum and Ageratina adenophora were found spread throughout the ecosystem. The invasion was fueled by anthropogenic disturbances such as leaving the agricultural lands, fallow and degradation of habitat. As a consequence, native species such as Artemisia indica and Urtica dioica were outcompeted mostly in the fringes of fallow lands, agricultural lands and in the disturbed sites. The intrusion was, however, less in the forest area, implying that community-managed dense canopy forests are less susceptible to invasion and routine management can offset the negative effects of invasion. Even though many negative consequences of the invasion were observed in the study sites, the possibility of the economically exploiting the biomass of invasive alien plant species for generating income locally was noticed.Banko Janakari, Vol. 27, No. 1, page: 31-42

scholarly journals Plantations and biodiversity: A comment on the debate in New Brunswick

2005 ◽  
Vol 81 (2) ◽  
pp. 265-269 ◽  
Author(s):  
Matthew G Betts ◽  
Antony W Diamond ◽  
Graham J Forbes ◽  
Kate Frego ◽  
Judy A Loo ◽  
...  
Keyword(s):  
New Brunswick ◽  
Tree Species ◽  
Native Species ◽  
Woody Debris ◽  
Scientific Information ◽  
Landscape Scale ◽  
Suitable Habitat ◽  
Negative Consequences ◽  
Intensively Managed ◽  
The Impact

The importance of biodiversity has become widely recognized but the best methods for conserving forest biodiversity are still being debated. Central to this debate is the influence of plantations and managed stands on local and landscape-scale biodiversity. A recent paper by Erdle and Pollard in The Forestry Chronicle (2002), which concluded that few plantations are strict monocultures in terms of the total number of tree species, could be interpreted as making the case that plantations have relatively minor consequences for biodiversity. We argue that: (1) it is not only the number of species, but also the identities and relative abundances of species that are of ecological importance, and (2) defining biodiversity in terms of tree species alone is of limited applicability. Existing research in New Brunswick on the impact of plantations on biodiversity at the stand scale reveals potentially significant biodiversity losses, at least in certain taxa. The proposal that incorporating more structural elements (e.g., snags, coarse woody debris, vertical structure) and retaining greater tree species diversity to ameliorate negative consequences of plantations remains a hypothesis to be tested in this region. Scientific information gathered in the following areas will allow better decision making: (1) to what degree are older plantations used by native species? (2) are productivity and survivorship of vertebrates in intensively managed stands similar to those in unmanaged forest? (3) are intensively managed stands suitable habitat for non-vertebrates? (4) are there thresholds in the response of some species to landscape-scale habitat loss caused by intensive forest management? Key words: plantations, biodiversity, species composition, landscape scale, stand structures

scholarly journals Developments in Drug Addiction During COVID-19—An Austrian Perspective Based on a Clinical Sample

2020 ◽  
Vol 11 ◽  
Author(s):  
Isabella Fuchs-Leitner ◽  
Kurosch Yazdi ◽  
Nikolas W. Gerstgrasser ◽  
Jan Rosenleitner
Keyword(s):  
Drug Use ◽  
Help Seeking ◽  
Early Stage ◽  
Clinical Sample ◽  
Original Data ◽  
Negative Consequences ◽  
Opioid Substitution Treatment ◽  
The Impact ◽  
Drug Use Disorder

Concerns about the negative consequences of the COVID-19 pandemic on people with substance use disorder (SUD) were raised by experts in the field around the world. Here we provide an Austrian perspective, discussing the impact of the pandemic on help-seeking patient with drug use disorder during the initial stage of the pandemic. Our perspectives are based on the situation as perceived at our clinical facility, and supported by original data collected from a small clinical sample of patients with drug use disorder (N = 32). The viewpoints and related descriptive data include the perceived individual impact of COVID-19, as well as various aspects of drug use behavior and the Austrian drug market before and after the onset of the pandemic. The consequences for a subgroup of patients in opioid substitution treatment (N = 24) are discussed. Surprisingly and in contrast to anticipated developments, we had the impression of a rather stable situation in Austria, at least at this early stage of the pandemic. The immediate impact of COVID-19 on these help-seeking patients with high levels of drug dependency seemed less severe than anticipated so far. Importantly, this observation might be a short-term effect for this already fragile group and careful monitoring of further developments as well as preparation of long-term strategies are advised. In general, problematic drug use is associated with many health risk factors and finding appropriate long-term health care strategies has to remain a top priority facing the pandemic. Our perspectives are restricted to observations from help-seeking patients at our clinic, and no conclusions for the general population can be directly drawn.

scholarly journals Modern aspects of international business development in the conditions of globalization

2021 ◽  
pp. 14-16
Author(s):  
Kseniia KOVTUNENKO ◽  
Hanna SHARKOVA ◽  
Viktoriia HURALSKA
Keyword(s):  
International Economic ◽  
International Business ◽  
Social Reproduction ◽  
Early Stage ◽  
Business Development ◽  
Negative Consequences ◽  
Economic Relations ◽  
Stage Of Development ◽  
The World ◽  
The Impact

Introduction. The paper considers the basis of international business development at global stage of internationalization. The paper emphasizes the shift of international business`s motives and forms concerning the innovative globalism. Analysis of the development of international business in the context of international management is covered in the works of В.А. Cherevatenko, K. Asvazappa, O.V. Mykhailovska, S. Robokk. In general, the issue of major trends and problems of international business is given much attention around the world. The purpose of the paper study of modern aspects of international business and new signs of social reproduction as a result of the impact of globalization. Results. In Ukraine, international business is only at an early stage of development. The country seeks to become a full partner in the world and European communities, and this requires the expansion and strengthening of international economic activity. Another distinctive feature of international business is that it is affected by many circumstances, including differences in language, geography, exchange rates and changes in the economy. The main forms of international business include: exports, imports, licensing, franchising, management contracts, turnkey contracts, joint ventures, foreign investment. Conclusion. Real globalization is characterized by the fact that international economic relations have covered almost all countries of the world and each of them depends on international business. The consequences of this are twofold: on the one hand, the country can enjoy all the benefits without feeling the negative consequences of the lack of certain resources, opportunities.

scholarly journals Evaluation of photosynthetic photon flux in lettuce cultivation at different shading levels

2020 ◽  
Vol 38 (1) ◽  
pp. 65-70
Author(s):  
Nilton Nélio Cometti ◽  
Josimar V da Silva ◽  
Everaldo Zonta ◽  
Raphael MA Cessa
Keyword(s):  
Flux Measurement ◽  
Crop Productivity ◽  
Photon Flux ◽  
Ambient Conditions ◽  
Photosynthetic Photon Flux ◽  
Transparent Plastic ◽  
Limit Value ◽  
Protected Cultivation ◽  
Set Up ◽  
The Impact

ABSTRACT Protected cultivation has grown in Brazil. Generally, greenhouses are covered with transparent plastic film and shading screen. The plastic, over time, loses its transparency due to pollution residues, dust and other debris. The loss of transparency reduces lightness, photosynthesis and leads to losses of productivity and product quality. The losses are not always detectable by the farmer. Additionally, internal shading screens are used to reduce heating transmission to the ground. The objective of this study was to evaluate the impact of shading on lettuce crop productivity and to determine the optimum shading to reach the highest productivity. Plots were set up inside and outside the greenhouse, with four shading levels with black screens (0, 35, 50 and 75%). The treatments were converted to real shading from the photosynthetic photon flux measurement. The results of fresh and dry phytomass were treated and analyzed by regression as a function of the real shading. In ambient conditions of photosynthetic photon fluxes around 1000 μmol m-2 s-1, reaching up to 2000 μmol m-2 s-1 at some hours of the day, typical of tropical environment, lettuce may support a shading of up to 50% without risk of productivity reduction; under these conditions, shading between 20 and 35% is beneficial, and can guarantee its maximum productivity in lettuce cultivation. It is recommended that the lettuce producer in protected cultivation monitors the shelf life of the plastic, avoiding that the shading exceeds 50%. In order to compare shading experiments, one should use the incident photon flux (FFI) for the whole crop cycle, indicating the minimum limit value of FFI = 600 mol m-2 cycle-1 for the crispy lettuce at an average temperature close to 21oC.

scholarly journals Habitat connectivity and resident shared predators determine the impact of invasive bullfrogs on native frogs in farm ponds

2014 ◽  
Vol 281 (1786) ◽  
pp. 20132621 ◽  
Author(s):  
Takashi Atobe ◽  
Yutaka Osada ◽  
Hayato Takeda ◽  
Misako Kuroe ◽  
Tadashi Miyashita
Keyword(s):  
Invasive Species ◽  
Common Carp ◽  
Native Species ◽  
Interspecific Interactions ◽  
Management Strategies ◽  
Habitat Connectivity ◽  
Negative Effects ◽  
The Face ◽  
The Difference ◽  
The Impact

Habitat connectivity is considered to have an important role on the persistence of populations in the face of habitat fragmentation, in particular, for species with conservation concern. However, it can also impose indirect negative effects on native species through the spread of invasive species. Here, we investigated direct and indirect effects of habitat connectivity on populations of invasive bullfrogs and native wrinkled frogs and how these effects are modified by the presence of common carp, a resident shared predator, in a farm pond system in Japan. The distribution pattern analysis using a hierarchical Bayesian modelling indicated that bullfrogs had negative effects on wrinkled frogs, and that these negative effects were enhanced with increasing habitat connectivity owing to the metapopulation structure of bullfrogs. The analysis also suggested that common carp mitigated these impacts, presumably owing to a top-down trophic cascade through preferential predation on bullfrog tadpoles. These presumed interspecific interactions were supported by evidence from laboratory experiments, i.e. predation by carp was more intense on bullfrog tadpoles than on wrinkled frog tadpoles owing to the difference in refuge use. Our results indicate that metacommunity perspectives could provide useful insights for establishing effective management strategies of invasive species living in patchy habitats.

scholarly journals REGULARITIES OF CHANGES IN THE STRUCTURE OF FIR FORESTS DAMAGED AS A RESULT OF THE INVASION OF POLYGRAPHUS PROXIMUS

2018 ◽  
Vol 8 (1) ◽  
pp. 14-23
Author(s):  
Никита Дебков ◽  
Nikita Debkov
Keyword(s):  
Native Species ◽  
Large Scale ◽  
Structural Changes ◽  
Southern Taiga ◽  
Green Moss ◽  
Negative Consequences ◽  
Natural Ecosystems ◽  
Tomsk Region ◽  
Polygraphus Proximus ◽  
The Impact

The era of globalization is accompanied by large-scale invasions of dendrophilic insects into forest ecosystems around the world. As a rule, the impact of invaders on native species leads to negative consequences. Perspective fore-casts of the development of the situation with alien species are not encouraging. In this regard, research on the nature and degree of transformation of natural ecosystems under the influence of invasive organisms is becoming increasingly important. The mechanism of invasion of Polygraphus proximus Blandf. in forests dominated by Siberian fir Abies sibirica Ledeb. on the territory of the Tomsk region is considered in the article. The aim of the research has been to evaluate structural changes in fir forests of Western Siberia damaged by Polygraphus proximus. Studies have been conducted in the southern part of the Tomsk region on permanent trial plots. The objects of research have been ferns and small-grass-green-moss fir forests. The structure of fir forests has been studied using standard methods. When assessing the health status, a specialized scale has been used. The main taxation parameters of the stand and natural renewal have been measured. As a result of the research, it has been revealed that the main influence of the invader falls on trees having an average diameter up to an average step of thickness inclusive. A consequence of this is an increase in the mean values of height, age, and diameter of the stand. Also, the result of the direct impact of the Polygraphus proximus is a decrease in the density of the stand by 34-37%, and the reserve by 30%. There is no significant influence of the provider on the change in the completeness and bonitet of the plantation. Reducing the closeness of crowns has led to the replacement of typical southern taiga and moss with high-grass groupings in the windows of desiccation. It is established that the activity of Polygraphus proximus can lead to a short-term change of species in mixed plantations, which is observed in ferns

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