scholarly journals Bottom-up effects of host-plant species diversity and top-down effects of ants interactively increase plant performance

2012 ◽  
Vol 279 (1746) ◽  
pp. 4464-4472 ◽  
Author(s):  
Xoaquín Moreira ◽  
Kailen A. Mooney ◽  
Rafael Zas ◽  
Luis Sampedro
Keyword(s):  
Species Diversity ◽  
Plant Diversity ◽  
Trophic Level ◽  
Plant Performance ◽  
Top Down ◽  
Bottom Up ◽  
The Third ◽  
Pine Tree ◽  
Third Trophic Level ◽  
Positive Effect

While plant diversity is well known to increase primary productivity, whether these bottom-up effects are enhanced by reciprocal top-down effects from the third trophic level is unknown. We studied whether pine tree species diversity, aphid-tending ants and their interaction determined plant performance and arthropod community structure. Plant diversity had a positive effect on aphids, but only in the presence of mutualistic ants, leading to a threefold greater number of both groups in the tri-specific cultures than in monocultures. Plant diversity increased ant abundance not only by increasing aphid number, but also by increasing ant recruitment per aphid. The positive effect of diversity on ants in turn cascaded down to increase plant performance; diversity increased plant growth (but not biomass), and this effect was stronger in the presence of ants. Consequently, bottom-up effects of diversity within the same genus and guild of plants, and top-down effects from the third trophic level (predatory ants), interactively increased plant performance.

The role of the third sector working with the hard and soft structures of public–private partnerships to promote individual health and reinvigorated, healthier communities

2020 ◽  
pp. 301-318
Author(s):  
Tony Chasteauneuf ◽  
Tony Thornton ◽  
Dean Pallant
Keyword(s):  
Health Outcomes ◽  
Local Authority ◽  
Third Sector ◽  
Public Private Partnerships ◽  
Top Down ◽  
Bottom Up ◽  
The Third ◽  
Individual Health ◽  
The Third Sector

This chapter discusses the role of the third sector working with the hard and soft structures of public–private partnerships to promote healthier individuals and communities. It considers how a recommitment to the 'local authority' of citizens and beneficiaries offers the possibility of revitalised and healthier individuals and reinvigorated and healthier communities, which are unachievable through the hard and soft structures of the commissioner/provider statutory approach. The chapter then identifies the pivotal dynamic of one-to-one relationships in these processes and their association with health outcomes (emotional, physical, and spiritual) alongside the opportunities and challenges in agencies engaging/re-engaging with the agency of citizens and beneficiaries. It explores the tension between the 'agency' of citizens and beneficiaries that constitutes bottom-up power and 'agencies' with top-down power. The chapter also looks at the benefits of embracing the expertise and investment of individuals and their communities in their personal and shared lives, how this can be supported and how it can be undermined.

Changing the Rules of the Game to Build the European Economy

2019 ◽  
pp. 41-91
Author(s):  
Jason Beckfield
Keyword(s):  
Political Economy ◽  
European Integration ◽  
Top Down ◽  
Historical Case ◽  
Bottom Up ◽  
The Third ◽  
European Social Fund ◽  
Social Fund ◽  
Rules Of The Game

This chapter describes the development of the European political economy since the 1957 Rome treaty. It uses econometric and historical case evidence to build the argument that European integration has advanced both from the top down and from the bottom up. The first part presents several measures of European integration to address the question of how we know integration when we see it. The second part describes two mechanisms of integration: redistribution from the top down via the European Social Fund, and integration from the bottom up through the formation of the Euro-Regions. The third part describes the development of a convergent European economy, where macroeconomic differences have been reduced through European integration, especially before the 1980s, and especially if economies are weighted by their populations.

Site-specific effects on productivity of an upper trophic-level marine predator: Bottom-up, top-down, and mismatch effects on reproduction in a colonial seabird

2006 ◽  
Vol 68 (2-4) ◽  
pp. 303-328 ◽  
Author(s):  
Robert M. Suryan ◽  
David B. Irons ◽  
Evelyn D. Brown ◽  
Patrick G.R. Jodice ◽  
Daniel D. Roby
Keyword(s):  
Trophic Level ◽  
Top Down ◽  
Bottom Up ◽  
Site Specific ◽  
Marine Predator ◽  
Specific Effects ◽  
Colonial Seabird

scholarly journals Co-infections and the third trophic level

2012 ◽  
Vol 26 (1) ◽  
pp. 1-2 ◽  
Author(s):  
Noah K. Whiteman
Keyword(s):  
Trophic Level ◽  
The Third ◽  
Third Trophic Level

Trophic Levels

Ecology ◽  
2012 ◽  
Author(s):  
Lee A. Dyer
Keyword(s):  
Trophic Level ◽  
Evolutionary Biology ◽  
Trophic Levels ◽  
Trophic Chain ◽  
The Third ◽  
Third Trophic Level ◽  
Primary Consumers ◽  
Trophic Chains ◽  
Secondary Consumers ◽  
Applied Fields

Trophic levels are determined by feeding relationships, with basal levels consisting of primary producers or detritus and upper levels based on consumption of these basal levels. Organisms on the second trophic level are referred to as primary consumers, which are in turn consumed by secondary consumers, and so on up a theoretical trophic chain. Primary consumers consist of herbivores and detritivores, while the third trophic level and those above include predators and parasites. Energy and matter move up trophic chains, and some compounds, including various toxins, may bioaccumulate at upper trophic levels. The concept of trophic level has generated a sizeable literature yielding useful ecological models, such as trophic cascades, and debates about top-down versus bottom-up regulation of herbivores. This article focuses on the contributions of the trophic-level concept to ecological theory, evolutionary biology, and the applied fields of agricultural and global change biology.

8. Europeanization

2019 ◽  
pp. 115-126 ◽  
Author(s):  
Tanja A. Börzel ◽  
Diana Panke
Keyword(s):  
European Union ◽  
The European Union ◽  
Foreseeable Future ◽  
Top Down ◽  
Bottom Up ◽  
Approaches To Studying ◽  
Fourth Section ◽  
The Third ◽  
Important Field ◽  
The Eu

The first section of the chapter explains what Europeanization means and outlines the main approaches to studying this phenomenon. The second section describes why this concept has become so prominent in research on the European Union (EU) and its member states. In the third section, the chapter reviews the state of the art with particular reference to how the EU affects states (‘top-down’ Europeanization). It illustrates the theoretical arguments with empirical examples. Similarly, the fourth section examines how states can influence the EU (‘bottom-up’ Europeanization) and provides some theoretical explanations for the empirical patterns observed. This is followed by a section that presents an overview of research that looks at linkages between bottom-up and top-down Europeanization, and considers the future of Europeanization research with regard to EU’s recent and current crises and challenges. The conclusion argues that Europeanization, despite the crises the EU has been facing, will remain an important field of EU research for the foreseeable future.

scholarly journals Bottom-up and top-down effects of tree species diversity on leaf insect herbivory

2017 ◽  
Vol 7 (10) ◽  
pp. 3520-3531 ◽  
Author(s):  
Bastien Castagneyrol ◽  
Damien Bonal ◽  
Maxime Damien ◽  
Hervé Jactel ◽  
Céline Meredieu ◽  
...  
Keyword(s):  
Species Diversity ◽  
Tree Species ◽  
Insect Herbivory ◽  
Tree Species Diversity ◽  
Top Down ◽  
Bottom Up
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