A conceptual framework of drought legacies in grasslands

2021 ◽  
Author(s):  
Lena M. Müller ◽  
Michael Bahn
Keyword(s):  
Climate Change ◽  
Conceptual Framework ◽  
Ecosystem Structure ◽  
Review Of The Literature ◽  
Cascading Effects ◽  
Extreme Climatic Events ◽  
Effects Of Drought ◽  
Ecosystem Structure And Functioning ◽  
Shape Of Potential

<p>As a consequence of climate change, extreme climatic events such as droughts will become more frequent and severe, affecting ecosystem structure and functioning, with implications for humans and society. While concurrent effects of drought events are comparatively well studied, the short- and longer-term changes in ecosystem structure and functioning triggered by drought (i.e. drought legacies) are far less understood. Furthermore, it has rarely been analysed how drought legacies alter the resistance to and recovery from subsequent drought events. To assess the overall impact of drought events on ecosystems and emerging cascading effects on societies, we need to advance the understanding of drought legacies and their long-lasting impacts on ecosystems. Based on a review of the literature on above- and belowground mechanisms underlying drought legacies in grasslands, we propose a conceptual framework, which identifies the factors determining the shape of potential legacy trajectories during recovery and post-recovery phases and synthesize the mechanisms leading to legacy responses to subsequent drought events.</p>

Small alteration – big impacts: effects of small-scale riparian forest management on host–parasite dynamics in streams

2017 ◽  
Vol 92 (1) ◽  
pp. 64-73 ◽  
Author(s):  
C. Lagrue ◽  
A.A. Besson ◽  
A. Lecerf
Keyword(s):  
Forest Management ◽  
Intermediate Host ◽  
Riparian Forest ◽  
Freshwater Ecosystems ◽  
Small Scale ◽  
Ecosystem Structure ◽  
Cascading Effects ◽  
Ecosystem Structure And Functioning ◽  
Riparian Forest Management ◽  
Parasite Dynamics

AbstractEnvironmental changes and ecological disturbances can have large and unpredictable effects on parasite dynamics. Increasing human impacts on freshwater ecosystems through land use may thus modify the distribution and abundance of parasites and have cascading effects on host populations. Here we tested the effects of small-scale riparian forest management on the nematode Cystidicoloides ephemeridarum and its insect intermediate host Ephemera danica in forested streams. We assessed the impacts of harvesting riparian trees on parasite prevalence and abundance concomitantly with host densities. We also looked at upstream and downstream reaches to document potential cascading effects on unaltered stream sections mediated by aerial dispersal of adult mayfly or downstream drift of E. danica larvae. We show that host densities and parasite levels (prevalence and abundance) increased significantly following riparian tree removal. Overall, parasite densities showed a 6- to 66-fold increase in harvested reaches compared to upstream, pristine reaches. Similar effects were also clear downstream of the disturbance. Thus, despite the small extent of riparian forest alteration along the study streams, both parasite and intermediate host were strongly affected. Small-scale riparian forest management may thus have large, unforeseen impacts on some aspects of freshwater ecosystem structure and functioning that are often ignored. Generally, understanding how human perturbations influence parasites is vital when trying to predict overall impacts on ecosystem structure and functioning, and how changes in infection dynamics may further affect host species.

scholarly journals Ecological mechanisms underlying aridity thresholds in global drylands

2021 ◽  
Author(s):  
Miguel Berdugo ◽  
Blai Vidiella Rocamora ◽  
Ricard Solé ◽  
Fernando T. Maestre
Keyword(s):  
Climate Change ◽  
Future Research ◽  
Ecosystem Structure ◽  
Water Shortages ◽  
Physiological Mechanisms ◽  
Abrupt Changes ◽  
Atmospheric Feedbacks ◽  
Ecosystem Structure And Functioning ◽  
Combat Climate Change ◽  
Ecosystem Changes

With ongoing climate change, the probability of crossing environmental thresholds promoting abrupt changes in ecosystem structure and functioning is higher than ever. In drylands (sites where it rains less than 60% of what is evaporated), recent research has shown how the crossing of three particular aridity thresholds (defining three consecutive phases, namely vegetation decline, soil disruption and systemic breakdown) leads to abrupt changes on ecosystem structural and functional attributes. Despite the importance of these findings and their implications to develop effective monitoring and adaptation actions to combat climate change, we lack a proper understanding of the mechanisms unleashing these abrupt shifts.Here we revise and discuss multiple mechanisms that may explain the existence of aridity thresholds observed across global drylands, and discuss the potential amplification mechanisms that may underpin hypothetical abrupt temporal shifts with climate change. We found that each aridity threshold is likely involving specific processes. In the vegetation decline phase we review mainly physiological mechanisms of plant adaptation to water shortages as main cause of this threshold. In the second threshold we identified three pathways involving mechanisms that propagates changes from plants to soil leading to a soil disruption: erosive mechanisms, mechanisms linked to an aridity-induced shrub encroachment and mechanisms linked to nutrient cycling and circulation. Finally, in the systemic breakdown phase we reviewed plant-plant amplification mechanisms triggered by survival limits of plants that may cause sudden diversity losses and plant-atmospheric feedbacks that may link vegetation collapse with further and critical aridification. By identifying, revising and linking relevant mechanisms to each aridity threshold, we catalogued a set of specific hypotheses and recommendations based on identified knowledge gaps concerning the study of mechanisms of threshold emergence in drylands. Moreover, we were able to establish plausible factors that are context dependent and may influence the occurrence of abrupt changes in time and we created a mechanistic-based conceptual model on how abrupt changes may emerge as aridity increases. This has importance for focusing future research efforts on aridity thresholds and for developing strategies to track, adapt to or even revert these abrupt ecosystem changes in the future.

Introduction

2018 ◽  
Author(s):  
Jonas Tallberg ◽  
Karin Bäckstrand ◽  
Jan Aart Scholte
Keyword(s):  
Climate Change ◽  
Human Rights ◽  
Conceptual Framework ◽  
Global Governance ◽  
Comprehensive Treatment ◽  
Human Rights Abuses ◽  
Sociological Approach ◽  
The Core ◽  
Governance Institutions

Legitimacy is central for the capacity of global governance institutions to address problems such as climate change, trade protectionism, and human rights abuses. However, despite legitimacy’s importance for global governance, its workings remain poorly understood. That is the core concern of this volume, which engages with the overarching question: whether, why, how, and with what consequences global governance institutions gain, sustain, and lose legitimacy. This introductory chapter explains the rationale of the book, introduces its conceptual framework, reviews existing literature, and presents the key themes of the volume. It emphasizes in particular the volume’s sociological approach to legitimacy in global governance, its comparative scope, and its comprehensive treatment of the topic. Moreover, a specific effort is made to explain how each chapter moves beyond existing research in exploring the book’s three themes: (1) sources of legitimacy, (2) processes of legitimation and delegitimation, and (3) consequences of legitimacy.

scholarly journals Detecting Climate Driven Changes in Chlorophyll-a in Deep Subalpine Lakes Using Long Term Satellite Data

Water ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 866
Author(s):  
Gary Free ◽  
Mariano Bresciani ◽  
Monica Pinardi ◽  
Nicola Ghirardi ◽  
Giulia Luciani ◽  
...  
Keyword(s):  
Climate Change ◽  
Chlorophyll A ◽  
Nutrient Dynamics ◽  
Cascading Effects ◽  
The North ◽  
Subalpine Lakes ◽  
Winter Temperatures ◽  
Decadal Climate ◽  
The North Atlantic Oscillation ◽  
Traditional Pattern

Climate change has increased the temperature and altered the mixing regime of high-value lakes in the subalpine region of Northern Italy. Remote sensing of chlorophyll-a can help provide a time series to allow an assessment of the ecological implications of this. Non-parametric multiplicative regression (NPMR) was used to visualize and understand the changes that have occurred between 2003–2018 in Lakes Garda, Como, Iseo, and Maggiore. In all four deep subalpine lakes, there has been a disruption from a traditional pattern of a significant spring chlorophyll-a peak followed by a clear water phase and summer/autumn peaks. This was replaced after 2010–2012, with lower spring peaks and a tendency for annual maxima to occur in summer. There was a tendency for this switch to be interspersed by a two-year period of low chlorophyll-a. Variables that were significant in NPMR included time, air temperature, total phosphorus, winter temperature, and winter values for the North Atlantic Oscillation. The change from spring to summer chlorophyll-a maxima, relatively sudden in an ecological context, could be interpreted as a regime shift. The cause was probably cascading effects from increased winter temperatures, reduced winter mixing, and altered nutrient dynamics. Future trends will depend on climate change and inter-decadal climate drivers.

scholarly journals Impact Assessment Analysis of Sea Level Rise in Denmark: A Case Study of Falster Island, Guldborgsund

2021 ◽  
Vol 13 (13) ◽  
pp. 7503
Author(s):  
Alexander Boest-Petersen ◽  
Piotr Michalak ◽  
Jamal Jokar Arsanjani
Keyword(s):  
Climate Change ◽  
Impact Assessment ◽  
Sea Level Rise ◽  
Sea Level ◽  
Alternative Methods ◽  
Projection Data ◽  
Storm Events ◽  
Cascading Effects ◽  
Local Levels

Anthropogenically-induced climate change is expected to be the contributing cause of sea level rise and severe storm events in the immediate future. While Danish authorities have downscaled the future oscillation of sea level rise across Danish coast lines in order to empower the coastal municipalities, there is a need to project the local cascading effects on different sectors. Using geospatial analysis and climate change projection data, we developed a proposed workflow to analyze the impacts of sea level rise in the coastal municipalities of Guldborgsund, located in Southeastern Denmark as a case study. With current estimates of sea level rise and storm surge events, the island of Falster can expect to have up to 19% of its landmass inundated, with approximately 39% of the population experiencing sea level rise directly. Developing an analytical workflow can allow stakeholders to understand the extent of expected sea level rise and consider alternative methods of prevention at the national and local levels. The proposed approach along with the choice of data and open source tools can empower other communities at risk of sea level rise to plan their adaptation.

scholarly journals Toward an integrated system of climate change and human health indicators: a conceptual framework

2021 ◽  
Vol 166 (3-4) ◽  
Author(s):  
Ann Y. Liu ◽  
Juli M. Trtanj ◽  
Erin K. Lipp ◽  
John M. Balbus
Keyword(s):  
Public Health ◽  
Climate Change ◽  
Health Outcomes ◽  
Conceptual Framework ◽  
Climate Adaptation ◽  
Health Indicators ◽  
Adaptation Strategies ◽  
Integrated System ◽  
Health Trends ◽  
Science And Policy

AbstractEnvironmental health indicators are helpful for tracking and communicating complex health trends, informing science and policy decisions, and evaluating public health actions. When provided on a national scale, they can help inform the general public, policymakers, and public health professionals about important trends in exposures and how well public health systems are preventing those exposures from causing adverse health outcomes. There is a growing need to understand national trends in exposures and health outcomes associated with climate change and the effectiveness of climate adaptation strategies for health. To date, most indicators for health implications of climate change have been designed as independent, individual metrics. This approach fails to take into account how exposure-outcome pathways for climate-attributable health outcomes involve multiple, interconnected components. We propose reframing climate change and health indicators as a linked system of indicators, which can be described as follows: upstream climate drivers affect environmental states, which then determine human exposures, which ultimately lead to health outcomes; these climate-related risks are modified by population vulnerabilities and adaptation strategies. We apply this new conceptual framework to three illustrative climate-sensitive health outcomes and associated exposure-outcome pathways: pollen allergies and asthma, West Nile virus infection, and vibriosis.

Klimaatverandering als journalistieke uitdaging: een literatuurstudie

2012 ◽  
Vol 40 (3) ◽  
Author(s):  
Richard van der Wurff
Keyword(s):  
Climate Change ◽  
The Political ◽  
Industrialized Countries ◽  
Review Of The Literature ◽  
News Values ◽  
Political Actors ◽  
Political Challenge ◽  
Media Logic ◽  
Political Framing ◽  
Selection Of

Climate change as a challenge for journalism: a review of the literature Climate change as a challenge for journalism: a review of the literature This literature review synthesizes 35 years of research on climate change reporting in industrialized countries. It focuses on the production and content of climate change news. Starting from the notion of the mediatisation of politics, the study shows that news values and media logic shape the selection of climate change related newsworthy events, while political actors and their logics determine the political framing of the issue. Next, implications for public opinion and mediated public debate are briefly assessed. Overall, the findings suggest that reporting focuses on threats and conflicts, favours national rather than transnational angles, reinforces ideological cleavages, downplays deliberative arguments, and disengages citizens. In conclusion, four lines of research are proposed that can help us better understand the role media might play in engaging citizens in a more deliberative mediated debate on climate change as important ecological and political challenge.

The impact of extreme climatic events on pasture-based dairy systems: a review

2017 ◽  
Vol 68 (12) ◽  
pp. 1158 ◽  
Author(s):  
J. Chang-Fung-Martel ◽  
M. T. Harrison ◽  
R. Rawnsley ◽  
A. P. Smith ◽  
H. Meinke
Keyword(s):  
Climate Change ◽  
Heat Stress ◽  
Heat Waves ◽  
Animal Health ◽  
Adaptation Strategies ◽  
Pasture Production ◽  
Potential Productivity ◽  
Extreme Climatic Events ◽  
Dairy Systems ◽  
The Impact

Extreme climatic events such as heat waves, extreme rainfall and prolonged dry periods are a significant challenge to the productivity and profitability of dairy systems. Despite projections of more frequent extreme events, increasing temperatures and reduced precipitation, studies on the impact of these extreme climatic events on pasture-based dairy systems remain uncommon. The Intergovernmental Panel on Climate Change has estimated Australia to be one of the most negatively impacted regions with additional studies estimating Australian production losses of around 16% in the agricultural sector and 9–19% between the present and 2050 in the south-eastern dairy regions of Australia due to climate change. Here we review the literature on the impact of climate change on pasture-based dairy systems with particular focus on extreme climatic events. We provide an insight into current methods for assessing and quantifying heat stress highlighting the impacts on pastures and animals including the associated potential productivity losses and conclude by outlining potential adaptation strategies for improving the resilience of the whole-farm systems to climate change. Adapting milking routines, calving systems and the introduction of heat stress tolerant dairy cow breeds are some proposed strategies. Changes in pasture production would also include alternative pasture species better adapted to climate extremes such as heat waves and prolonged periods of water deficit. In order to develop effective adaptation strategies we also need to focus on issues such as water availability, animal health and associated energy costs.

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