scholarly journals A test of the evolution of increased competitive ability in two invaded regions

2019 ◽  
Author(s):  
Michael C. Rotter ◽  
Mario Vallejo-Marin ◽  
Liza M. Holeski
Keyword(s):  
North America ◽  
Competitive Ability ◽  
Native Plants ◽  
List Type ◽  
Native Plant ◽  
Herbivore Resistance ◽  
Specialist Herbivore ◽  
Specialist Herbivores ◽  
The Uk ◽  
Resistance Traits

AbstractFinding patterns that predict and explain the success of non-native species has been an important focus in invasion ecology. The evolution of increased competitive ability (EICA) hypothesis has been a frequently used framework to understand invasion success. Evolution of increased competitive ability predicts that 1. Non-native populations will escape from coevolved specialist herbivores and this release from specialist herbivores should result in relaxed selection pressure on specialist-related defense traits, 2. There will be a trade-off between allocation of resources for resistance against specialist herbivores and allocation to traits related to competitive ability and 3. This shift will allow more allocation to competitive ability traits.We tested the predictions of EICA in the model plant Mimulus guttatus, a native of western North America (WNA). We compared how well the predictions of EICA fit patterns in two non-native regions, the United Kingdom (UK) and eastern North America (ENA). Coupled with extensive herbivore surveys we quantified genetic variation for herbivore resistance traits and fitness/ competitive ability traits to test adherence to the predictions of EICA in a common greenhouse environment.Herbivore communities differed significantly between WNA, UK, and ENA populations with evidence of specialist herbivore escape in the UK, but not necessarily the ENA plants. Compared to native plants, resistance traits were lower in non-native UK plants with the exception of trichome density, while the non-native ENA plants had equivalent or higher levels of herbivore resistance traits. The UK plants had increased competitive traits than native plants while the ENA plants had equivalent competitive traits to native plants. The UK plants, but not the ENA plants, showed some signs of tradeoffs between resistance traits and fitness/ competitive ability.Synthesis. Plants from the UK conformed to predictions of EICA more closely than those from ENA. The UK invasion is an older, more successful invasion, suggesting that support for EICA may be highest in more successful invasions. The lack of comprehensive conformity of either non-native region to the predictions of EICA also leaves room for other hypotheses that may add to our mechanistic understanding of the success of non-native plant invasions.

Invasive shrub removal benefits native plants in an eastern deciduous forest of North America

2019 ◽  
Vol 12 (1) ◽  
pp. 3-10
Author(s):  
Erynn Maynard-Bean ◽  
Margot Kaye
Keyword(s):  
North America ◽  
Plant Diversity ◽  
Natural Regeneration ◽  
Native Plants ◽  
Tree Regeneration ◽  
Native Plant ◽  
Shrub Species ◽  
Invasive Shrub ◽  
Overstory Tree ◽  
Sampling Approach

AbstractIn eastern deciduous forests of North America, invasive shrubs are increasing in richness and abundance at the expense of native species across taxa. Invasive shrubs create an understory that is more dense than both recent and historical preinvasion conditions. Interest in invasive shrub removal to restore native habitat is growing, but our understanding of natural regeneration following treatment of a diverse invasive shrub community is lagging. Using an invasive shrub removal experiment, we provide insight into the effect of repeated removal of a suite of 18 invasive shrub species dominated by border privet (Ligustrum obtusifolium Siebold & Zucc.). In 2009, invasive shrubs were removed from five 20-m-diameter treatment plots, each with a paired control plot. Seven years later, we find an increase in plant diversity, native understory species abundance, and overstory tree species regeneration for individuals under a meter in height. For plants 1 to 4 m in height, the removal treatment has a positive effect on understory woody species, but there has been no change in regenerating overstory trees. A lack of overstory tree regeneration to greater heights is not surprising, given the time frame and the closed-canopy conditions. However, other factors, such as white-tailed deer (Odocoileus virginianus Zimmermann) browse, could be serving as an impediment to taller tree regeneration in the forest understory. An ambient sampling approach in unmanaged, invaded, and uninvaded forest has been used in other studies to estimate the potential impacts of invasive shrub species to native plant communities. However, in this study the ambient sampling approach underestimated the impacts of invasive shrubs compared to their experimental removal. Overall, invasive shrub removal increased plant diversity and allowed passive natural regeneration of native plants that exceeded native cover in the unmanaged, ambient forest under minimal invasive shrub abundance.

scholarly journals The future of social care funding: who pays?

2016 ◽  
Vol 22 (1) ◽  
pp. 10-44 ◽  
Author(s):  
T. Kenny ◽  
J. Barnfield ◽  
L. Daly ◽  
A. Dunn ◽  
D. Passey ◽  
...  
Keyword(s):  
Phase 1 ◽  
List Type ◽  
Political Debate ◽  
Term Care ◽  
Means Testing ◽  
Financial Products ◽  
Funding System ◽  
The Government ◽  
The Uk ◽  
Care Costs

AbstractWith the UK population ageing, deciding upon a satisfactory and sustainable system for the funding of people’s long-term care (LTC) needs has long been a topic of political debate. Phase 1 of the Care Act 2014 (“the Act”) brought in some of the reforms recommended by the Dilnot Commission in 2011. However, the Government announced during 2015 that Phase 2 of “the Act” such as the introduction of a £72,000 cap on Local Authority care costs and a change in the means testing thresholds1 would be deferred until 2020. In addition to this delay, the “freedom and choice” agenda for pensions has come into force. It is therefore timely that the potential market responses to help people pay for their care within the new pensions environment should be considered. In this paper, we analyse whether the proposed reforms meet the policy intention of protecting people from catastrophic care costs, whilst facilitating individual understanding of their potential care funding requirements. In particular, we review a number of financial products and ascertain the extent to which such products might help individuals to fund the LTC costs for which they would be responsible for meeting. We also produce case studies to demonstrate the complexities of the care funding system. Finally, we review the potential impact on incentives for individuals to save for care costs under the proposed new means testing thresholds and compare these with the current thresholds. We conclude that:∙Although it is still too early to understand exactly how individuals will respond to the pensions freedom and choice agenda, there are a number of financial products that might complement the new flexibilities and help people make provision for care costs.∙The new care funding system is complex making it difficult for people to understand their potential care costs.∙The current means testing system causes a disincentive to save. The new means testing thresholds provide a greater level of reward for savers than the existing thresholds and therefore may increase the level of saving for care; however, the new thresholds could still act as a barrier since disincentives still exist.

Interactions between invasive plants and heavy metal stresses: a review

2021 ◽  
Author(s):  
Jian Li ◽  
Zhanrui Leng ◽  
Yueming Wu ◽  
Yizhou Du ◽  
Zhicong Dai ◽  
...  
Keyword(s):  
Invasive Species ◽  
Invasive Plants ◽  
Native Plants ◽  
Escape Behavior ◽  
Negative Influence ◽  
Plant Litter ◽  
Global Changes ◽  
Native Plant ◽  
Anthropogenic Contamination ◽  
The Impact

Abstract Global changes have altered the distribution pattern of the plant communities, including invasive species. Anthropogenic contamination may reduce native plant resistance to the invasive species. Thus, the focus of the current review is on the contaminant biogeochemical behavior among native plants, invasive species and the soil within the plant-soil ecosystem to improve our understanding of the interactions between invasive plants and environmental stressors. Our studies together with synthesis of the literature showed that a) the impacts of invasive species on environmental stress were heterogeneous, b) the size of the impact was variable, and c) the influence types were multidirectional even within the same impact type. However, invasive plants showed self-protective mechanisms when exposed to heavy metals (HMs) and provided either positive or negative influence on the bioavailability and toxicity of HMs. On the other hand, HMs may favor plant invasion due to the widespread higher tolerance of invasive plants to HMS together with the “escape behavior” of native plants when exposed to toxic HM pollution. However, there has been no consensus on whether elemental compositions of invasive plants are different from the natives in the polluted regions. A quantitative research comparing plant, litter and soil contaminant contents between native plants and the invaders in a global context is an indispensable research focus in the future.

scholarly journals ICD, Mental Disorder and British Nosologists: An assessment of the uniquely British contribution to psychiatric classification

1994 ◽  
Vol 165 (1) ◽  
pp. 1-3 ◽  
Author(s):  
Michael Shepherd
Keyword(s):  
North America ◽  
Mental Disorder ◽  
Historical Survey ◽  
Psychiatric Classification ◽  
The Subject ◽  
The Uk ◽  
National Systems ◽  
The Way

During several recent international meetings on classification, there have been frequent references to national systems of classification developed and used in Europe, North America and many other countries. The UK has been notably absent from this list. As Professor Kendell, in his brief historical survey of the subject, points out: “British psychiatry does not have, and indeed never has had, any important diagnostic concepts of its own in the way that French, American, and Scandinavian psychiatry still do” (Kendell, 1985).

scholarly journals PhytophthoraSpecies Are Common on Nursery Stock Grown for Restoration and Revegetation Purposes in California

Plant Disease ◽  
2019 ◽  
Vol 103 (3) ◽  
pp. 448-455 ◽  
Author(s):  
S. Rooney-Latham ◽  
C. L. Blomquist ◽  
K. L. Kosta ◽  
Y. Y. Gou ◽  
P. W. Woods
Keyword(s):  
North America ◽  
Phytophthora Species ◽  
Molecular Techniques ◽  
Crown Rot ◽  
Native Plant ◽  
Nursery Stock ◽  
Plant Nursery ◽  
Root And Crown Rot ◽  
Symptomatic Tissue ◽  
First Time

Phytophthora tentaculata was detected for the first time in North America in 2012 in a nursery on sticky monkeyflower plant (Diplacus aurantiacus) and again in 2014 on outplanted native plants. At that time, this species was listed as a federally actionable and reportable pathogen by the USDA. As a result of these detections, California native plant nurseries were surveyed to determine the prevalence of Phytophthora species on native plant nursery stock. A total of 402 samples were collected from 26 different native plant nurseries in California between 2014 and 2016. Sampling focused on plants with symptoms of root and crown rot. Symptomatic tissue was collected and tested by immunoassay, culture, and molecular techniques (PCR). Identifications were made using sequences from the internal transcribed spacer (ITS) rDNA region, a portion of the trnM-trnP-trnM, or the atp9-nad9 mitochondrial regions. Phytophthora was confirmed from 149 of the 402 samples (37%), and from plants in 22 different host families. P. tentaculata was the most frequently detected species in our survey, followed by P. cactorum and members of the P. cryptogea complex. Other species include P. cambivora, P. cinnamomi, P. citricola, P. hedraiandra, P. megasperma, P. multivora, P. nicotianae, P. niederhauserii, P. parvispora, P. pini, P. plurivora, and P. riparia. A few Phytophthora sequences generated from mitochondrial regions could not be assigned to a species. Although this survey was limited to a relatively small number of California native plant nurseries, Phytophthora species were detected from three quarters of them (77%). In addition to sticky monkeyflower, P. tentaculata was detected from seven other hosts, expanding the number of associated hosts. During this survey, P. parvispora was detected for the first time in North America from symptomatic crowns and roots of the nonnative Mexican orange blossom (Choisya ternata). Pathogenicity of P. parvispora and P. nicotianae was confirmed on this host. These findings document the widespread occurrence of Phytophthora spp. in native plant nurseries and highlight the potential risks associated with outplanting infested nursery-grown stock into residential gardens and wildlands.

The State of the Art in Management Education Applicable to Aerospace Activities

1967 ◽  
Vol 71 (677) ◽  
pp. 344-348
Author(s):  
J. V. Connolly
Keyword(s):  
Management Education ◽  
State Of The Art ◽  
Aerospace Industry ◽  
List Type ◽  
Industrial Training ◽  
The Past ◽  
The Subject ◽  
Economic Necessity ◽  
The Uk ◽  
The Impact

During the past two years, there has been a sharp acceleration to the interest which industry has displayed in the subject of management education. This can be attributed to these factors: —(a) A more widespread realisation of the gap developing between the UK and a number of foreign economies, as manifested by diverging rates of the major economic indicators.(b) The attainment of top-management responsibilities by a younger generation of managers, many of whom had been given some earlier training and who were more conscious of its value than the incumbents of the job from earlier generations.(c) The publication of the Franks, Robbins and (in the aerospace industry) the Plowden reports.(d) The impact of the Industrial Training Boards making it manifest, in terms of serious levies, that training was an economic necessity and therefore must be investigated thoroughly.Notwithstanding the widespread awakening of interest, it is very belated and sets numerous problems. The problems are in two areas—scale and quality.

Chapter II. The World Economy

1983 ◽  
Vol 106 ◽  
pp. 26-38
Keyword(s):  
North America ◽  
Industrial Production ◽  
World Economy ◽  
Western Europe ◽  
West Germany ◽  
The Us ◽  
The World ◽  
The Uk ◽  
A Minor ◽  
Minor Extent

The recovery in the OECD area gathered pace in the second quarter, when its total GDP probably increased by as much as 1 per cent. The rise was, however, heavily concentrated in North America and particularly the US. There may well have been a slight fall in Western Europe, where the level of industrial production hardly changed and increases in gross product in West Germany and, to a minor extent, in France were outweighed by falls in Italy and (according to the expenditure measure) the UK.

Beyond evidence-based policy and practice

2013 ◽  
Vol 16 (2) ◽  
pp. 20-36
Author(s):  
Mike Fisher
Keyword(s):  
North America ◽  
Practice Research ◽  
Evidence Based ◽  
Policy And Practice ◽  
Research And Practice ◽  
Social Work Research ◽  
Recent Developments ◽  
The Uk ◽  
The Impact ◽  
The Relationship

This paper concerns the impact of social work research, particularly on practice and practitioners. It explores the politics of research and how this affects practice, the way that university-based research understands practice, and some recent developments in establishing practice research as an integral and permanent part of the research landscape. While focusing on implications for the UK, it draws on developments in research across Europe, North America and Australasia to explore how we can improve the relationship between research and practice.

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