Potential impacts of ocean acidification on the Puget Sound food web

Abstract Busch, D. S., Harvey, C. J., and McElhany, P. 2013. Potential impacts of ocean acidification on the Puget Sound food web. – ICES Journal of Marine Science, 70: 823–833. Ecosystem impacts of ocean acidification (OA) were explored by imposing scenarios designed to mimic OA on a food web model of Puget Sound, a large estuary in northwestern USA. The productivity of functional groups containing mostly calcifiers was decreased while still allowing other species groups to respond to the scenarios in a dynamic way through indirect effects. Results focus on changes in ecosystem services and structure. Sometimes the direct and indirect effects of OA countered each other due to interactions between predators and prey within the food web, leading to little change in the food web. In other cases, direct and indirect effects caused greater change in the food web than anticipated from direct effects alone. Results were strongly affected by the group on which OA was directly imposed, with changes in copepod productivity being the most influential. While there is much uncertainty in our predictions, focusing on the complex interactions among species, and between species and their environment, will yield better understanding of how ecosystems may respond to OA.

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Separating direct and indirect effects of rising temperatures on biogenic volatile emissions in the Arctic

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.2008901117 ◽

2020 ◽

Vol 117 (51) ◽

pp. 32476-32483

Author(s):

Riikka Rinnan ◽

Lars L. Iversen ◽

Jing Tang ◽

Ida Vedel-Petersen ◽

Michelle Schollert ◽

...

Keyword(s):

Indirect Effects ◽

Model Simulation ◽

Atmospheric Composition ◽

The Arctic ◽

Dependent Manner ◽

Direct And Indirect Effects ◽

Direct Effects ◽

Arctic Ecosystems ◽

Voc Emissions ◽

Local Climate

Volatile organic compounds (VOCs) are released from biogenic sources in a temperature-dependent manner. Consequently, Arctic ecosystems are expected to greatly increase their VOC emissions with ongoing climate warming, which is proceeding at twice the rate of global temperature rise. Here, we show that ongoing warming has strong, increasing effects on Arctic VOC emissions. Using a combination of statistical modeling on data from several warming experiments in the Arctic tundra and dynamic ecosystem modeling, we separate the impacts of temperature and soil moisture into direct effects and indirect effects through vegetation composition and biomass alterations. The indirect effects of warming on VOC emissions were significant but smaller than the direct effects, during the 14-y model simulation period. Furthermore, vegetation changes also cause shifts in the chemical speciation of emissions. Both direct and indirect effects result in large geographic differences in VOC emission responses in the warming Arctic, depending on the local vegetation cover and the climate dynamics. Our results outline complex links between local climate, vegetation, and ecosystem–atmosphere interactions, with likely local-to-regional impacts on the atmospheric composition.

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Direct and indirect effects of near-future pCO2 levels on zooplankton dynamics

Marine and Freshwater Research ◽

10.1071/mf15296 ◽

2017 ◽

Vol 68 (2) ◽

pp. 373 ◽

Cited By ~ 5

Author(s):

Cédric L. Meunier ◽

María Algueró-Muñiz ◽

Henriette G. Horn ◽

Julia A. F. Lange ◽

Maarten Boersma

Keyword(s):

Ocean Acidification ◽

Indirect Effects ◽

Trophic Levels ◽

Model Organisms ◽

High Pco2 ◽

Direct And Indirect Effects ◽

Oxyrrhis Marina ◽

Short Term Exposure ◽

Zooplankton Growth ◽

Seawater Pco2

Ocean acidification has direct physiological effects on organisms, for example by dissolving the calcium carbonate structures of calcifying species. However, non-calcifiers may also be affected by changes in seawater chemistry. To disentangle the direct and indirect effects of ocean acidification on zooplankton growth, we undertook a study with two model organisms. Specifically, we investigated the individual effects of short-term exposure to high and low seawater pCO2, and different phytoplankton qualities as a result of different CO2 incubations on the growth of a heterotrophic dinoflagellate (Oxyrrhis marina) and a copepod species (Acartia tonsa). It was observed previously that higher CO2 concentrations can decrease phytoplankton food quality in terms of carbon:nutrient ratios. We therefore expected both seawater pCO2 (pH) and phytoplankton quality to result in decreased zooplankton growth. Although we expected lowest growth rates for all zooplankton under high seawater pCO2 and low algal quality, we found that direct pH effects on consumers seem to be of lesser importance than the associated decrease in algal quality. The decrease in the quality of primary producers under high pCO2 conditions negatively affected zooplankton growth, which may lead to lower availability of food for the next trophic level and thus potentially affect the recruitment of higher trophic levels.

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Effect of Expectation and Disconfirmation on Postexposure Product Evaluations: A Causal Path Analysis

Psychological Reports ◽

10.2466/pr0.1979.45.3.803 ◽

1979 ◽

Vol 45 (3) ◽

pp. 803-810 ◽

Cited By ~ 7

Author(s):

James L. Taylor ◽

Richard M. Durand

Keyword(s):

Path Analysis ◽

Analysis Of Variance ◽

Indirect Effects ◽

Causal Model ◽

Direct And Indirect Effects ◽

Hierarchical Analysis ◽

Direct Effects ◽

Product Evaluations ◽

Variance Design ◽

Causal Path

Oliver (1977) recently analyzed the direct effects of consumers' expectations and disconfirmation on posttrial evaluations of products using a hierarchical analysis of variance design. The research reported by Oliver is reevaluated and extended in this paper. A causal model is presented and path analysis used to assess both direct and indirect effects of consumers' expectations and a disconfirming experience on ratings of posttrial affect and intentions to purchase. Results suggest that (1) both expectations and disconfirmation influence postexposure ratings of affect with the experience of disconfirmation exerting the greater effect; (2) disconfirmation only indirectly influences intentions to purchase through its impact on affective evaluations; and, (3) expectations influence intentions to purchase in two different ways—both directly and indirectly through posttrial judgments of affect.

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Path analysis for grain yield in barnyard millet (Echinochloa frumentacea (Roxb.) link )

Bangladesh Journal of Botany ◽

10.3329/bjb.v44i1.22739 ◽

2015 ◽

Vol 44 (1) ◽

pp. 147-150

Author(s):

R Prakash ◽

C Vanniarajan

Keyword(s):

Grain Yield ◽

Indirect Effects ◽

Association Studies ◽

Path Coefficient ◽

Direct And Indirect Effects ◽

Direct Effects ◽

Path Coefficient Analysis ◽

Barnyard Millet ◽

Straw Yield ◽

Echinochloa Frumentacea

Path coefficient analysis was studied in 65 genotypes of barnyard millet to find out the association studies of characters and their direct and indirect effects on grain yield/plant. Results exhibited that single earhead weight had maximum direct effects on grain yield/plant followed by straw yield/plant, earhead length and plant height. DOI: http://dx.doi.org/10.3329/bjb.v44i1.22739 Bangladesh J. Bot. 44(1): 147-150, 2015 (March)

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Direct and indirect effects of predatory young-of-year fishes in a dryland river food web

Freshwater Biology ◽

10.1111/fwb.12954 ◽

2017 ◽

Vol 62 (8) ◽

pp. 1410-1421 ◽

Cited By ~ 3

Author(s):

Corey A. Krabbenhoft ◽

Ayesha S. Burdett ◽

Thomas F. Turner

Keyword(s):

Food Web ◽

Indirect Effects ◽

Direct And Indirect Effects ◽

Dryland River

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Direct and indirect effects of ocean acidification and warming on a marine plant–herbivore interaction

Oecologia ◽

10.1007/s00442-013-2683-y ◽

2013 ◽

Vol 173 (3) ◽

pp. 1113-1124 ◽

Cited By ~ 82

Author(s):

Alistair G. B. Poore ◽

Alexia Graba-Landry ◽

Margaux Favret ◽

Hannah Sheppard Brennand ◽

Maria Byrne ◽

...

Keyword(s):

Ocean Acidification ◽

Indirect Effects ◽

Direct And Indirect Effects ◽

Marine Plant ◽

Plant Herbivore Interaction ◽

Plant Herbivore ◽

Herbivore Interaction

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Stomatal Traits and Barley (Hordeum Vulgare L.) Forage Yield in Drought Conditions of Northeastern Mexico

Plants ◽

10.3390/plants10071318 ◽

2021 ◽

Vol 10 (7) ◽

pp. 1318

Author(s):

Foroughbakhch Pournavab Rahim ◽

Torres Tapia María Alejandra ◽

Zamora Villa Víctor Manuel ◽

Treviño Ramirez José Elías ◽

Ngangyo Heya Maginot

Keyword(s):

Indirect Effects ◽

Vegetation Index ◽

Block Design ◽

Forage Yield ◽

Effect Of Temperature ◽

Direct And Indirect Effects ◽

Direct Effects ◽

Lower Side ◽

Infrared Technology ◽

Positive Direct

Infrared technology is a practical, fast, non-destructive method that helps in forecasting plant development and can be used to select physiological traits, instead of other methodologies that require more time and breeding efforts. According to the statistical analyses and the relationship between the direct and indirect effects of the variables, this technology could serve as the basis for implementing a genotype selection methodology. Awnless barley was assessed in a randomized block design with three replicates in two crop seasons at Mexico’s northeastern region. Two samplings were carried out during crop development: at 75 and 90 days after sowing. The infrared and stomatal sensors were used to identify the direct and indirect effects of stomata’s traits on dry forage yield. The data were analyzed in a subdivided plot design, using mean comparison tests, correlation coefficients and path analyses, finding significant differences (p < 0.05) among localities and among samplings. Dry forage yield was significant and positively correlated with plant height (r = 0.578) and canopy temperature (r = 0.724), and negatively correlated with the leaf upper side stomatal width (r = −0.409) and the leaf lower side stomatal width (r = −0.641), chlorophyll content and vegetation index. Temperature, chlorophyll, density and leaf lower side stomatal index had the strongest direct effects on yield. Therefore, the infrared technology appears as a way to select high yielding awnless forage barley, to obtain the correlation, the positive direct effect of temperature and the negative effect of chlorophyll. Due to their direct effects, low density and low leaf underside stomatal indexes can also help in the indirect selection of higher yielding forage barley genotypes.

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Psychological and Theological Predictors of Environmental Attitudes among a Sample of UK Churchgoers

Journal of Empirical Theology ◽

10.1163/15709256-12341411 ◽

2020 ◽

Vol 33 (2) ◽

pp. 220-244

Author(s):

Andrew Village

Keyword(s):

Indirect Effects ◽

Environmental Attitudes ◽

Religious Affiliation ◽

Biblical Interpretation ◽

Psychological Type ◽

Direct And Indirect Effects ◽

Direct Effects ◽

Psychological Variables ◽

Religious Conservatism ◽

Biblical Literalism

Abstract This paper builds on previous studies of UK churchgoers by examining the factors that predict concern for the environment and willingness to make sacrifices to preserve it. A sample of 825 churchgoers from a range of denominations completed a questionnaire that contained items used to assess psychological preferences, biblical literalism, and a range of theological stances toward creation. Psychological variables showed both direct and indirect effects on environmentalism that were in line with previous work by environmental psychologists. Indirect effects were related to the way that some psychological type preferences either shape biblical interpretation or are associated with religious conservatism. Religious affiliation had no direct effects on environmentalism, but did have indirect effects through literalism and religious conservatism. Beliefs about dominion and eschatology directly reduced concern, but dominion was also positively associated with stewardship, which emerged as the main promoter of both concern and sacrifice.

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Forecasting ocean acidification impacts on kelp forest ecosystems

PLoS ONE ◽

10.1371/journal.pone.0236218 ◽

2021 ◽

Vol 16 (4) ◽

pp. e0236218

Author(s):

Adam J. Schlenger ◽

Rodrigo Beas-Luna ◽

Richard F. Ambrose

Keyword(s):

Ocean Acidification ◽

Food Web ◽

Trophic Level ◽

Marine Ecosystem ◽

Kelp Forest ◽

Forest Community ◽

Coralline Algae ◽

Forcing Mechanisms ◽

Over Time ◽

Food Web Model

Ocean acidification is one the biggest threats to marine ecosystems worldwide, but its ecosystem wide responses are still poorly understood. This study integrates field and experimental data into a mass balance food web model of a temperate coastal ecosystem to determine the impacts of specific OA forcing mechanisms as well as how they interact with one another. Specifically, we forced a food web model of a kelp forest ecosystem near its southern distribution limit in the California large marine ecosystem to a 0.5 pH drop over the course of 50 years. This study utilizes a modeling approach to determine the impacts of specific OA forcing mechanisms as well as how they interact. Isolating OA impacts on growth (Production), mortality (Other Mortality), and predation interactions (Vulnerability) or combining all three mechanisms together leads to a variety of ecosystem responses, with some taxa increasing in abundance and other decreasing. Results suggest that carbonate mineralizing groups such as coralline algae, abalone, snails, and lobsters display the largest decreases in biomass while macroalgae, urchins, and some larger fish species display the largest increases. Low trophic level groups such as giant kelp and brown algae increase in biomass by 16% and 71%, respectively. Due to the diverse way in which OA stress manifests at both individual and population levels, ecosystem-level effects can vary and display nonlinear patterns. Combined OA forcing leads to initial increases in ecosystem and commercial biomasses followed by a decrease in commercial biomass below initial values over time, while ecosystem biomass remains high. Both biodiversity and average trophic level decrease over time. These projections indicate that the kelp forest community would maintain high productivity with a 0.5 drop in pH, but with a substantially different community structure characterized by lower biodiversity and relatively greater dominance by lower trophic level organisms.

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Motivasi, Komunikasi, dan Kepuasan Kerja Terhadap Kinerja Tenaga Kependidikan Pada Fakultas Insititut Pertanian Bogor

Jurnal Manajemen ◽

10.32832/jm-uika.v7i2.1111 ◽

2016 ◽

Vol 7 (2) ◽

pp. 152

Author(s):

Sri Nooryani ◽

Hendri Tanjung ◽

Ibdalsyah MA

Keyword(s):

Job Satisfaction ◽

Path Analysis ◽

Indirect Effect ◽

Indirect Effects ◽

P Value ◽

Direct And Indirect Effects ◽

Test Results ◽

Direct Effects ◽

Independent Variables ◽

Positive Effects

The path analysis shows that motivation has significantly direct and indirect effects to communication. Motivation does not have significant effects to performance but have indirect effects through job satisfaction. This is because motivation has significant direct effects to job satisfaction. Communication has direct and indirect effects to performance. The indirect effect is through job satisfaction. Job satisfaction has significant direct effects to performance.The T-test results show that the effects of independent variables (motivation and communication) have significant positive effects to job satisfaction with p-value of 0.00. This value is less than alpha value (5%). Coefficient determination (R2) is of 0.741. This means that motivation and communication can explain the diversity of job satisfaction as high as 74.1% and the rest, which is of 25.9%, explains by other factors that are not used in this research. Independent variables (motivation, communication and job satisfaction) have significant positive effects to performance with p-value of 0.00. The coefficient determination (R2) is of 0.574. This means that motivation, communication, and job satisfaction can explain performance as high as 57.4% and the rest, which is of 42.6%, explains by other factors.

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