What happens when you add salt: predicting impacts of secondary salinisation on shallow aquatic ecosystems by using an alternative-states model

2003 ◽  
Vol 51 (6) ◽  
pp. 715 ◽  
Author(s):  
Jenny A. Davis ◽  
Megan McGuire ◽  
Stuart A. Halse ◽  
David Hamilton ◽  
Pierre Horwitz ◽  
...  
Keyword(s):  
Aquatic Ecosystems ◽  
Aquatic Vegetation ◽  
Submerged Macrophytes ◽  
Halophilic Bacteria ◽  
Freshwater Species ◽  
Alternative States ◽  
Secondary Salinisation ◽  
Decision Making Processes ◽  
Restoration Strategies

Alternative-states theory commonly applied, for aquatic systems, to shallow lakes that may be dominated alternately by macrophytes and phytoplankton, under clear-water and enriched conditions, respectively, has been used in this study as a basis to define different states that may occur with changes in wetland salinity. Many wetlands of the south-west of Western Australia are threatened by rapidly increasing levels of salinity as well as greater water depths and permanency of water regime. We identified contrasting aquatic vegetation states that were closely associated with different salinities. Salinisation results in the loss of freshwater species of submerged macrophytes and the dominance of a small number of more salt-tolerant species. With increasing salinity, these systems may undergo further change to microbial mat-dominated systems composed mostly of cyanobacteria and halophilic bacteria. The effect of other environmental influences in mediating switches of vegetation was also examined. Colour and turbidity may play important roles at low to intermediate salinities [concentration of total dissolved solids (TDS) <10 000 mg L–1]; however, coloured or turbid wetlands are rarely found at intermediate to high salinities (>10 000 mg L–1 TDS). The role of nutrients remains largely unquantified in saline systems. We propose that alternative-states theory provides the basis of a conceptual framework for predicting impacts on wetlands affected by secondary salinisation. The ability to recognise and predict a change in state with changes in salinity adds a further tool to decision-making processes. A change in state represents a fundamental change in ecosystem function and may be difficult to reverse. This information is also important for the development of restoration strategies. Further work is required to better understand the influence of temporal variation in salinity on vegetation states and probable hysteresis effects.

scholarly journals Diverse role of Macrophytes in aquatic ecosystems: A brief review

2019 ◽  
Vol 19 ◽  
pp. 40-48
Author(s):  
Mitu De ◽  
◽  
Chayanika Roy ◽  
Suchismita Medda ◽  
Sulagna Roy ◽  
...  
Keyword(s):  
Aquatic Ecosystem ◽  
Aquatic Ecosystems ◽  
Aquatic Macrophytes ◽  
Food Source ◽  
Aquatic Vegetation ◽  
Submerged Macrophytes ◽  
Freshwater Ecosystems ◽  
Aquatic Life ◽  
Aquatic Flora

The aquatic ecosystem is composed of aquatic flora and fauna which interact together in maintaining the aquatic ecosystem. Aquatic macrophytes are macroscopic forms of aquatic vegetation, including macro algae, mosses, ferns and angiosperms found in aquatic habitat. Macrophytes of freshwater ecosystems have diverse roles to play in the structure and functioning of these aquatic ecosystems. The depth, density, diversity and types of macrophytes present in a system are indicators of water body health. Aquatic vegetation can influence the water quality too. Macrophytes are considered as an important component of the aquatic ecosystem as the habitat and food source for aquatic life. Of all the biological treatments for controlling eutrophication, submerged macrophytes, has been recognized as being the most effective. This paper is a brief review of the diverse role of macrophytes in an aquatic ecosystem.

History and Transport Policy

Transfers ◽  
2014 ◽  
Vol 4 (1) ◽  
pp. 45-62 ◽  
Author(s):  
Ueli Haefeli ◽  
Fritz Kobi ◽  
Ulrich Seewer
Keyword(s):  
Knowledge Transfer ◽  
Transport Policy ◽  
Science And Policy ◽  
Direct Knowledge ◽  
Academic System ◽  
Decision Making Processes ◽  
Policy And Planning ◽  
Policy Solutions ◽  
Do So

Based on analysis of two case studies in the Canton of Bern, this article examines the question of knowledge transfer from history to transport policy and planning in the recent past in Switzerland. It shows that for several reasons, direct knowledge transfer did not occur. In particular, historians have seldom become actively involved in transport planning and policy discourses, probably partly because the academic system offers no incentive to do so. However, historical knowledge has certainly influenced decision-making processes indirectly, via personal reflection of the actors in the world of practice or through Switzerland's strongly developed modes of political participation. Because the potential for knowledge transfer to contribute to better policy solutions has not been fully utilized, we recommend strengthening the role of existing interfaces between science and policy.

scholarly journals Representativeness in Geographical Indications: A Comparison between the State-Driven and Producer-Driven Systems in Vietnam and France

2021 ◽  
Vol 13 (9) ◽  
pp. 5056
Author(s):  
Barbara Pick ◽  
Delphine Marie-Vivien
Keyword(s):  
Qualitative Methodology ◽  
The State ◽  
Geographical Indications ◽  
Driven Systems ◽  
Local Stakeholders ◽  
Collective Processes ◽  
Decision Making Processes ◽  
Legal Frameworks ◽  
The Relationship

This paper explores the issues of representativeness and participation in the collective processes involved in the elaboration of the geographical indications (GI) specifications and the governance of the GI initiatives. The objective is to understand the relationship among collective dynamics, representativeness of relevant stakeholders, and the legal frameworks for the protection of GIs. Using a qualitative methodology based on an analysis of six case studies in France and Vietnam, we show the role of the law in shaping the different ways of understanding and implementing the concept of representativeness in the French producer-led and the Vietnamese state-driven approaches to GI protection. In France, the GI specifications result from negotiations among all legitimate stakeholders, which may prove long, complex, and lead to standards that can continue to be challenged after the GI registration. We also argue that the rules for the representation of all GI users in the decision-making processes do not necessarily lead to fairness. In Vietnam, local stakeholders usually have a consultative role under the authority of the State, resulting in their little understanding and low use of the GI. Their empowerment is further hindered by the involvement of state authorities in the management of the producers’ associations. We conclude by discussing in-between solutions to promote the producers’ representation and participation.

Mitigating Burnout Through Organizational Justice: Customer Support Workers’ Experiences of Customer Injustice and Emotional Labor

2021 ◽  
pp. 089331892110120
Author(s):  
Heewon Kim ◽  
Rebecca B. Leach
Keyword(s):  
Procedural Justice ◽  
Customer Service ◽  
Emotional Labor ◽  
Call Center ◽  
Service Industries ◽  
Interpersonal Justice ◽  
Negatively Associated ◽  
Customer Support ◽  
Decision Making Processes

Employee burnout is a critical organizational concern that can be prevalent among customer support workers whose day-to-day tasks inherently include emotional labor. This study examines emotional labor and burnout among call center workers in customer service industries, specifically focusing on the influences of injustices from customers and supervisors. The findings demonstrate that: (a) customer injustice was associated with an increase in emotional labor, which in turn exacerbated customer support workers’ disengagement and exhaustion; (b) interpersonal justice perceived in the interactions with supervisors was negatively associated with disengagement; and (c) procedural justice perceived in supervisors’ decision-making processes was also negatively associated with disengagement. The findings indicate the mitigating role of interpersonal and procedural justice in reducing burnout among customer support workers.

scholarly journals Omnivorous Carp (Carassius gibelio) Increase Eutrophication in Part by Preventing Development of Large-Bodied Zooplankton and Submerged Macrophytes

Water ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1497
Author(s):  
Vladimir Razlutskij ◽  
Xueying Mei ◽  
Natallia Maisak ◽  
Elena Sysova ◽  
Dzmitry Lukashanets ◽  
...  
Keyword(s):  
Aquatic Ecosystems ◽  
Submerged Macrophytes ◽  
Benthic Algae ◽  
Plankton Community ◽  
Prussian Carp ◽  
Omnivorous Fish ◽  
Outdoor Experiment ◽  
Nitrogen Concentrations ◽  
Lower Biomass

Fish, being an important consumer in aquatic ecosystems, plays a significant role by affecting the key processes of aquatic ecosystems. Omnivorous fish consume a variety of food both from pelagic and benthic habitats and may directly or indirectly affect the plankton community as well as the lake trophic state. We conducted a 72-day outdoor experiment in mesocosms with and without Prussian carp (Carassius auratus) to evaluate the effect of this often-stocked omnivorous fish on the plankton community and water quality. We found that the presence of fish increased the biomass of planktonic algae, total and inorganic suspended solids, leading to decreased light intensity in the water and a lower biomass of benthic algae. Fish also prevented development of submerged macrophytes and the establishment of large-bodied zooplankton. However, the fish did not increase nitrogen concentrations and even was lowered total phosphorus levels, in part due to nutrient storage in the fish. We conclude that stocking of Prussian carp should be avoided, or removed where stocked and abundant, to obtain good ecological quality of shallow lakes, characterized by clear water and high abundance of macrophytes.

scholarly journals Heart and Mind: Essential Components in Sound Decision-Making

2020 ◽  
Vol 4 (Supplement_1) ◽  
pp. 364-364
Author(s):  
Michaela Clark ◽  
Julie Hicks Patrick ◽  
Michaela Reardon
Keyword(s):  
Decision Making ◽  
Decision Quality ◽  
Cluster Solution ◽  
Cognitive Resources ◽  
Cluster Membership ◽  
Essential Components ◽  
Decision Making Processes ◽  
Affective Components ◽  
Heart And Mind

Abstract Consumer tasks permit an ecologically-valid context in which to examine the contributions of affective and cognitive resources to decision-making processes and outcomes. Although previous work shows that cognitive factors are important when individuals make decisions (Patrick et al., 2013; Queen et al.), the role of affective components is less clear. We examine these issues in two studies. Study 1 used data from 1000+ adults to inform a cluster analysis examining affective aspects (importance, meaningfulness) of making different types of decisions. A 4-cluster solution resulted. In Study 2, we used affective cluster membership and cognitive performance as predictors of experimental decision-making outcomes among a subset of participants (N = 60). Results of the regression (F(2, 40) = 6.51, p &lt; .01, R2 = .25.) revealed that both the affective clusters (b = .37, p = .01) and cognitive ability (b = -.30, p = .04) uniquely contributed to the variance explained in decision quality. Age did not uniquely contribute. Results are discussed in the context of developing measures that enable us to move the field forward.

scholarly journals Group size and aquatic vegetation modulates male preferences for female shoals in wild zebrafish, Danio rerio

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Aditya Ghoshal ◽  
Anuradha Bhat
Keyword(s):  
Group Size ◽  
Aquatic Vegetation ◽  
Natural Habitat ◽  
Ecological Factors ◽  
Choice Test ◽  
Female Group ◽  
Aquatic Flora ◽  
In The Wild ◽  
The Individual

AbstractShoaling decisions in the wild are determined by a combination of innate preferences of the individual along with the interplay of multiple ecological factors. In their natural habitat as well as in the laboratory, zebrafish is a shoaling fish. Here, we investigate the role of group size and associated vegetation in shaping shoaling preferences of wild male zebrafish. We studied the association preference of males to groups of female shoals in a multi-choice test design. We found that males made greater proportion of visits to an 8-female group compared to 2 and 4-female groups. However, males spent similar proportions of time across the three female-containing groups. When artificial vegetation was incorporated along with female number as an additional factor, we found that males prefer high and moderately vegetated patches compared to low or no-vegetation groups, irrespective of the number of females in these patches. Based on experiments using a novel multi-choice design, our results show that preference for group size can change due to interaction of two separate factors. This work is a first attempt to understand the role of aquatic flora in determining shoaling preferences in zebrafish, using an experimental paradigm consisting of a gradation in female and vegetation densities.

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