scholarly journals Deposition of shells modify nutrient fluxes in marine sediments: effects of nutrient enrichment and mitigation by bioturbation below mussel farms

2020 ◽  
Vol 12 ◽  
pp. 315-325
Author(s):  
P Bergström ◽  
Y Durland ◽  
M Lindegarth

Farming of extractive species such as filter feeding bivalves has been proposed as a potential method to mitigate impacts of eutrophication in marine environments. For such efforts to be sustainable, potential negative effects from mussel farms, such as accumulation of biodeposits in sediment below them, need to be considered and addressed. Benthic burrowing macrofauna strongly influence biogeochemical processes in soft bottom marine habitats by sediment reworking and irrigation and, thus, have the potential to mitigate some of the negative impacts. However, not all biodeposits are organic matter; shells that accumulate on and in the sediment below mussel farms also have the potential to influence processes in the sediment, the activity of bioturbators and the fluxes across the sediment-water interface. In this study, we evaluated the mitigation potential of the bioturbating polychaete Hediste diversicolor in sediments enriched with mussel waste material and the relative impact of mussel shells within the sediment matrix. The polychaetes generally increased fluxes and sediment oxygen uptake. With an observed tendency of increased fluxes of nutrients in sediments containing shells compared to sediments without, the results indicate that the accumulation of shell has a potential to further increase the mitigative effect of the polychaetes by influencing the solute fluxes across the sediment-water interface.

2019 ◽  
Vol 32 (1) ◽  
Author(s):  
Leonardo Martins Barbosa ◽  
Sheila Giardini Murta

AbstractThe literature shows that retirement can bring both positive and negative effects. However, there are few tested interventions for preparing workers for this transition and avoiding or minimizing its negative impacts. This paper presents a study with multiple groups that examined the social validity of an intervention for retirement education grounded in contextual behavioral science and acceptance and commitment therapy. Twenty-seven workers aged 29 to 65 divided into three intervention groups participated (group 1, N = 15; group 2, N = 9; group 3, N = 3). According to the participants’ evaluations, the intervention provided socially valid goals, socially acceptable procedures, and socially important effects. However, some improvements are still needed, such as the use of more dynamic methods, better formatted printed material, and increased fidelity between the content’s implementation and the prescribed activities. The positive results indicate that contextual behavioral science may bolster the development of interventions whose components possess evidence for their social validity. The further evaluation of the intervention via a clinical trial study will offer more robust evidence for its effectiveness. It is hoped that by increasing the availability of theory-based interventions in this area, the present study will promote valid strategies to facilitate better adjustment to retirement.


2021 ◽  
Vol 2 (1) ◽  
pp. 69-79
Author(s):  
Hurmat Ejaz ◽  
Esther Somanader ◽  
Uday Dave ◽  
Hermann Ehrlich ◽  
M. Azizur Rahman

Didymosphenia geminata diatoms, or Didymo, was first found to be an invasive species that could have negative impacts on the environment due to the aggressive growth of its polysaccharide-based stalks. The stalks’ adhesive properties have prompted park officials to alert the general public to limit further spread and contamination of this algae to other bodies of water. Although the negative effects of Didymo have been studied in the past, recent studies have demonstrated a potential positive side to this alga. One of the potential benefits includes the structural component of the polysaccharide stalks. The origin of the polysaccharides within stalks remains unknown; however, they can be useful in a waste management and agricultural setting. The primary purpose of this study was to describe both the harmful and beneficial nature of Didymo. Important outcomes include findings related to its application in various fields such as medicine and technology. These polysaccharides can be isolated and studied closely to produce efficient solar power cells and batteries. Though they may be harmful while uncontained in nature, they appear to be very useful in the technological and medical advancement of our society.


2021 ◽  
Vol 13 (15) ◽  
pp. 8235
Author(s):  
Alfredo J. Escribano ◽  
Maria Belen Peña ◽  
Carlos Díaz-Caro ◽  
Ahmed Elghannam ◽  
Eva Crespo-Cebada ◽  
...  

Meat production and consumption have been claimed to have negative impacts on the environment, and even on the consumer’s health. In this sense, alternative sources of protein, mainly meat substitutes and cultured meat, have emerged due to those perceived negative effects. Our paper carries out a choice experiment to analyze the preferences of 444 Spanish consumers and their willingness to pay for plant-based and cultured meats, as compared to conventional meat. Spain was considered of interest for this study due to its significant gastronomic culture, with high-quality meat products that make a great contribution to the economy, meaning that this could be a suitable and also challenging market in which to test alternative sources of protein. The findings show that consumers’ motivations and their interactions with these products are complex. Additionally, a cluster analysis allowed us to identify three types of consumers in terms of preference for these products: price-sensitive millennials, conscious/concerned consumers, and indifferent consumers. Only one group showed some level of acceptance of these alternative products meats.


2014 ◽  
Vol 59 (3) ◽  
pp. 997-1010 ◽  
Author(s):  
Audrey H. Sawyer ◽  
Olesya Lazareva ◽  
Kevin D. Kroeger ◽  
Kyle Crespo ◽  
Clara S. Chan ◽  
...  

Botany ◽  
2009 ◽  
Vol 87 (1) ◽  
pp. 22-25 ◽  
Author(s):  
M. E. Ostry ◽  
G. Laflamme

Forest health is described and perceived in different ways by the general public, land owners, managers, politicians, and scientists, depending on their values and objectives. Native tree pathogens and diseases are often associated with negative impacts even though damage is limited or not widespread. Too often, the concepts of tree health and forest health are used interchangeably and are not related to scale. Similar to fire, occurrences of disease outbreaks focus on the negative effects. However, native pathogens often exist in equilibrium with natural forest communities so their critical ecological roles are not easily discernible. Examined holistically, native fungi and diseases, dead and dying trees, and the many complex ecological interactions among them provide valuable benefits that ultimately contribute to sustainable, healthy forest ecosystems.


Author(s):  
Rizki Mohamed

The Tagueleft basin is geographically located in the northern edges of the Middle High Atlas, which is a geomorphological fragile area. The impact of human activity has accelerated water erosion in this mountains area. This is reflected in dynamic and unstable foothills, a decrease in forests density and degradation in the production of the land. On the other hand, land degradation due to human overexploitation of natural resources has increased land degradation in the area. The interest in the risk of erosion on the foothills in the area under study comes in the context of our contribution to clarify the role of geomatical and geomorphological approaches in explaining and identifying the mechanisms responsible for current foothills dynamism through water erosion and its negative impacts on the environment and local development. The aim of the study was to use the EPM (Erosion Potential Méthod) which is formulated by Slobodan Gavrilovic for erosion in mountainous areas and to test the reliability of its results based on fieldwork and remote sensing data. The results of the erosion assessment and its quantification by applying the coefficient (W) for the theoretical model in the area under study have shown that erosion is very important and it touches on wide areas as it appears through the domain classification of the distribution erosion in Tagueleft basin.


Insects ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 999
Author(s):  
Cody Prouty ◽  
Paola Barriga ◽  
Andrew K. Davis ◽  
Vera Krischik ◽  
Sonia Altizer

Neonicotinoids are the most widely used insecticides in North America. Numerous studies document the negative effects of neonicotinoids on bees, and it remains crucial to demonstrate if neonicotinoids affect other non-target insects, such as butterflies. Here we examine how two neonicotinoids (imidacloprid and clothianidin) affect the development, survival, and flight of monarch butterflies, and how these chemicals interact with the monarch’s milkweed host plant. We first fed caterpillars field-relevant low doses (0.075 and 0.225 ng/g) of neonicotinoids applied to milkweed leaves (Asclepias incarnata), and found no significant reductions in larval development rate, pre-adult survival, or adult flight performance. We next fed larvae higher neonicotinoid doses (4–70 ng/g) and reared them on milkweed species known to produce low, moderate, or high levels of secondary toxins (cardenolides). Monarchs exposed to the highest dose of clothianidin (51–70 ng/g) experienced pupal deformity, low survival to eclosion, smaller body size, and weaker adult grip strength. This effect was most evident for monarchs reared on the lowest cardenolide milkweed (A. incarnata), whereas monarchs reared on the high-cardenolide A. curassavica showed no significant reductions in any variable measured. Our results indicate that monarchs are tolerant to low doses of neonicotinoid, and that negative impacts of neonicotinoids depend on host plant type. Plant toxins may confer protective effects or leaf physical properties may affect chemical retention. Although neonicotinoid residues are ubiquitous on milkweeds in agricultural and ornamental settings, commonly encountered doses below 50 ng/g are unlikely to cause substantial declines in monarch survival or migratory performance.


Land ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 1269
Author(s):  
María J. Andrade ◽  
João Pedro Costa ◽  
Eduardo Jiménez-Morales

In recent years, cruise tourism has increased the negative effects caused by touristification in many European port cities. Despite this, these cities are in a great competition to be a destination, a tourist-port. Cruise tourism has come to stay, and a steady growth can be expected in a post-COVID-19 scenario, but at what cost? The tourist-port demands highly effective planning answers occurring simultaneously, and the global pandemic crisis provides a buffer of time to seek best practices, combining the expected economical (re)development with social, environmental, and cultural sustainability. This paper proposes five different strategies that contribute to finding a sustainable coexistence between tourist ports and their cities. To this end, trans-scalar strategies developed in previous research from different disciplines have been studied and categorized in a port-city context, in order to provide a holistic viewpoint on the measures carried out to maximize the benefits and limit the negative impacts of cruise tourism on cities.


2020 ◽  
Vol 2 (2) ◽  
pp. 109-116
Author(s):  
Suhandi ◽  
Azhar Jaafar

Modernisation is the consequence of the demands of the development that brings negative impacts to the society. It is undeniable that modernization also brings abundance of positive impacts that ease the life of people and that modernization and humanization cannot be separated. In this context, the youth are considered as unstable being, who easily being controlled by multi-access communication technology; from social, fashion, behaviour, lifestyle, and ideology. Almost all of the damaging sides of technology affect the youth. Religion as the spiritual agent has a major role in combating this change in the society. Religion can act as the social control to hinder from immoral behaviour and worthless actions among the society. The main issue in the current study is to investigate the role of religion in strengthening the moral among the teenagers. This research was conducted by using qualitative method. Data were collected through observation, interview and documentation. The participants of this research were the people of the rural areas in Bandar Lampung. After data collection was carried out, the data were processed qualitatively using the data reduction process, data exposure, and data verification. To conclude, the existence of the negative effects of modernization resulted from lack of religious virtues and parents’ control over their children’s social behaviour.


Author(s):  
Zeynep Karsavuran

This chapter attempts to draw attention to the effects of COVID-19 on tourism and hospitality employment. Specifically, two major impacts on the workforce are detected and discussed within this scope: job losses and deterioration of the working conditions. Job loss causes financial strain, deterioration of physical and psychological health, and social consequences for the dismissed individuals. In addition, employees who remain in the organizations also face negative impacts of the COVID-19 crisis such as health risks, increasing precariousness, and changing working methods. These labour issues are further discussed for their consequences on the tourism and hospitality industry, and solution and recommendations are provided to overcome the negative effects.


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