Interactive effects of light and nutrients on stream algal growth modified by forest management in boreal landscapes

The effects of three common agrochemicals, lindane, methyl parathion and atrazine, on crustacean Daphnia magna, alga Selenastrum capricornutum and marine bacterium Vibrio fischeri were investigated in this study. Methyl parathion was the most toxic compound towards all three organisms, while lindane was more toxic to Daphnia magna and Vibrio fischeri than atrazine, and atrazine was more toxic to Selenastrum capricornutum than lindane. Among the three aquatic organisms, Selenastrum capricornutum was most sensitive in detecting lindane and atrazine toxicity, while Daphnia magna was most sensitive in detecting methyl parathion toxicity. The interactive effects of the pesticides were also investigated. The interactive effect between lindane and methyl parathion on survival of Daphnia magna was synergistic, while the ones between lindane and atrazine and between methyl parathion and atrazine were generally additive. The interactive effect of the three pesticides applied together on Daphnia magna was synergistic. The interactive effect of the three pesticides on the growth of Selenastrum capricornutum was antagonistic with few cases of addition, while the effect of all the three pairs of pesticides on algal growth was also antagonistic. The interactive effect of lindane and methyl parathion on Vibrio fischeri was additive.

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Increased light availability enhances tolerance against ocean acidification stress in Halimeda opuntia

10.1101/2020.10.09.333799 ◽

2020 ◽

Author(s):

Zhangliang Wei ◽

Chao Long ◽

Yating Zhang ◽

Yuanzi Huo ◽

Fangfang Yang ◽

...

Keyword(s):

Ocean Acidification ◽

Stress Resistance ◽

Organic Molecules ◽

Light Availability ◽

Algal Growth ◽

Interactive Effects ◽

Carotenoid Content ◽

Metabolic Enzyme ◽

Soluble Carbohydrate ◽

List Type

AbstractAlthough the adverse impacts of ocean acidification (OA) on marine calcifiers have been investigated substantially, the anti-stress abilities regulated by increased light availability are unclear. Herein, the interactive effects of three light levels combined with two pCO2 concentrations on the physiological acclimation of the calcifying macroalga Halimeda opuntia were investigated using a pCO2–light coupling experiment. The results indicate that OA exhibits an adverse role in influencing algal growth, calcification, photosynthesis and other physiological performances in H. opuntia. The relative growth rate in elevated pCO2 significantly declined by 13.14%–41.29%, while net calcification rates decreased by nearly three-fold under OA. Notably, increased light availability could enhance stress resistance by the accumulation of soluble organic molecules, especially soluble carbohydrate, soluble protein and free amino acids, and in combination with metabolic enzyme-driven activities alleviated OA stress. Carotenoid content in low light conditions accumulated remarkably and rapid light curves for relative electron transport rate was significantly enhanced by increasing light intensities, indicating that this new organization of the photosynthetic machinery in H. opuntia accommodated light variations and elevated pCO2 conditions. Taken together, the results describe stress resistance by the enhancement of metabolic performance in marine calcifiers to mitigate OA stress.One sentence summaryIncreased light availability enhances stress resistance in Halimeda opuntia by the accumulation of soluble organic molecules and enzyme-driven activities to alleviate ocean acidification stress.Credit authorship contribution statementFangfang Yang and Lijuan Long conceived and designed the experiments. Zhangliang Wei performed the experiments and wrote the paper. Yuanzi Huo analyzed the data, while Chao Long and Yating Zhang contributed materials and analysis tools. Lijuan Long agrees to serve as the author responsible for contact and communication.HighlightsElevated pCO2 adversely affects the physiological performance of Halimeda.Moderately high light increases soluble organic molecules and enzymatic-driven activities.Increased light availability enables H. opuntia to alleviate the negative effects of ocean acidification.

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Assessment of long term interaction between the endemic seagrass P. oceanica and the exotic green alga C. cylindracea in the South Eastern coast of Spain (Murcia Region)

10.7287/peerj.preprints.1065 ◽

2015 ◽

Author(s):

Jaime Bernardeau-Esteller ◽

Rocio García-Muñoz ◽

Lázaro Marín-Guirao ◽

Jose Miguel Sandoval-Gil ◽

Ruiz Juan Fernandez

Keyword(s):

Green Alga ◽

Algal Growth ◽

Interactive Effects ◽

Limiting Factors ◽

Eastern Coast ◽

Future Research ◽

The South ◽

South Eastern ◽

Leaf Canopy

The green alga Caulerpa cylindracea has rapidly spread throughout the Western Mediterranean during the last 20 years. Compared with other native benthic communities, Posidonia oceanica meadows seems to be highly resistant to the colonization by the alga. Nonetheless, it is suggested that in the long-term C. cylindracea could affect the seagrass altering its vitality, structure and functions, however little is known about the interactive effects between these two structuring species. To this end, the abundance of both macrophytes was quantified and monitored in invaded and non-invaded localities of the South Eastern coast of Spain (Murcia Region) over an 8-year period (2007-2014). Results indicate that no differences were highlighted between invaded and no invaded meadows and all the monitored meadows showed stable or progressive trends in shoot density, meadow cover and net population growth. Regardless of the depth, in all of the invaded localities C. cylindracea biomass present inside the seagrass leaf canopy was about 10 to 50–fold lower than that measured just outside the leaf canopy. In summary, our results do not support the existence of a long-term competitive interaction between the invasive alga and the native seagrass, at least in the studied meadows and at the meadow level. C. cylindracea forms huge biomass gradients associated to the seagrass meadow edges that are stable with time, which suggests the existence of highly limiting conditions for algal growth and survival under the P. oceanica leaf canopy. Future research on such limiting factors could help us to understand the invasive capacity of the alga and the factors involved in the resistance of native habitats to bioinvasions.

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Ecosystem-level regulation of boreal lake phytoplankton by ultraviolet radiationThis paper is part of the series “Forty Years of Aquatic Research at the Experimental Lakes Area”.

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f09-119 ◽

2009 ◽

Vol 66 (11) ◽

pp. 2002-2010 ◽

Cited By ~ 10

Author(s):

Marguerite A. Xenopoulos ◽

Peter R. Leavitt ◽

David W. Schindler

Keyword(s):

Community Composition ◽

Algal Growth ◽

Interactive Effects ◽

Algal Community ◽

Humic Lakes ◽

Experimental Lakes Area ◽

Planktonic Diatoms ◽

Algal Groups ◽

Algal Abundance ◽

Uvb Exposure

Unique and interactive effects of ultraviolet radiation (UVR), temperature, and water column mixing on phytoplankton abundance and community composition were quantified using regression and multivariate analysis for lakes of differing transparencies and UVR exposure regimes located at the Experimental Lakes Area in Canada. Abundance of planktonic diatoms and chrysophytes (as fucoxanthin) and total algae (as chlorophylls) were negatively correlated with UVB exposure (R2 = 0.57 and R2 = 0.64, respectively) in slightly stained lakes. In contrast, concentrations of both filamentous Cyanobacteria and dinoflagellates were positively correlated with UVB levels in eutrophic and humic lakes (dissolved organic carbon >9 mg·L–1) (R2 = 0.23 and R2 = 0.27), whereas all algal groups were uncorrelated with UVB in oligotrophic ecosystems. Although univariate analyses suggested that surface water temperature explained more variation in algal abundance than UVB, principal components analyses revealed that the two factors often covaried and could not be statistically disentangled. Instead, it appears that strong UVB effects on lake algal communities occur commonly when optical and thermal properties interact to maximize exposure to high irradiances. Unexpectedly, UVR could either suppress or stimulate surface algal growth depending on the precise combination of lake parameters and algal community composition.

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Forest management to increase carbon sequestration in boreal Pinus sylvestris forests

Plant and Soil ◽

10.1007/s11104-021-05038-0 ◽

2021 ◽

Author(s):

Karolina Jörgensen ◽

Gustaf Granath ◽

Björn D. Lindahl ◽

Joachim Strengbom

Keyword(s):

Forest Management ◽

Pinus Sylvestris ◽

Boreal Forests ◽

Management Practices ◽

C Sequestration ◽

Interactive Effects ◽

Forest Sites ◽

C Stocks ◽

C Stock ◽

Natural Climate

Abstract Background and aims Forest management towards increased carbon (C) sequestration has repeatedly been suggested as a “natural climate solution”. We evaluated the potential of altered management to increase C sequestration in boreal Pinus sylvestris forest plantations. Methods At 29 forest sites, distributed along a 1300 km latitudinal gradient in Sweden, we studied interactive effects of fertilization and thinning on accumulation of C in standing biomass and the organic horizon over a 40 year period. Results Abstention from thinning increased the total C stock by 50% on average. The increase was significant (14% on average) even when C in the removed timber was included in the total ecosystem C pool. Fertilization of thinned stands increased stocks similarly regardless of including (11%) or excluding (12%) removed biomass, and fertilization combined with abstention from thinning had a synergistic effect on C stocks that generated an increase of 79% (35% when removed timber was included in the C stock). A positive effect of fertilization on C stocks was observed along the entire gradient but was greater in relative terms at high latitudes. Fertilization also reduced soil respiration rates. Conclusion Taken together, our results suggest that changed forest management practices have major potential to increase the C sink of boreal forests. Although promising, these benefits should be evaluated against the undesired effects that such management can have on economic revenue, timber quality, biodiversity and delivery of other ecosystem services.

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Dissolved Organic Matter Quality and Biofilm Composition Affect Microbial Organic Matter Uptake in Stream Flumes

Water ◽

10.3390/w12113246 ◽

2020 ◽

Vol 12 (11) ◽

pp. 3246

Author(s):

Gabriele Weigelhofer ◽

Tania Sosa Jirón ◽

Tz-Ching Yeh ◽

Gertraud Steniczka ◽

Matthias Pucher

Keyword(s):

Organic Matter ◽

Dissolved Organic Matter ◽

Algal Growth ◽

Soluble Reactive Phosphorus ◽

Single Pulse ◽

Interactive Effects ◽

Nutrient Concentrations ◽

Cow Dung ◽

Organic Matter Quality ◽

Reactive Phosphorus

Agriculture delivers significant amounts of dissolved organic matter (DOM) to streams, thereby changing the composition and biodegradability of the aquatic DOM. This study focuses on the interactive effects of DOM quality and biofilm composition on the degradation of DOM in a laboratory flume experiment. Half of the flumes were exposed to light to stimulate algal growth, the other half was shaded. Leachates of deciduous leaves, maize leaves, and cow dung were added to the flumes in a single pulse and changes of DOC (dissolved organic carbon) and nutrient concentrations, DOM composition (absorbance and fluorescence data), chlorophyll-a concentrations, bacterial abundances, and enzymatic activities were recorded over a week. DOM was taken up with rates of 50, 109, and 136 µg DOC L−1 h−1 for dung, leaf, and maize leachates, respectively, in the light flumes and 37, 80, and 170 µg DOC L−1 h−1 in the dark flumes. DOC uptake correlated strongly with initial SRP (soluble reactive phosphorus) and DOC concentrations, but barely with DOM components and indices. Algae mostly stimulated the microbial DOC uptake, but the effects differed among differently aged biofilms. We developed a conceptual model of intrinsic (DOM quality) and external (environmental) controlling factors on DOM degradation, with the microbial community acting as biotic filter.

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Interactive effects of wildfire, forest management, and isolation on amphibian and parasite abundance

Ecological Applications ◽

10.1890/12-0316.1 ◽

2013 ◽

Vol 23 (2) ◽

pp. 479-492 ◽

Cited By ~ 10

Author(s):

Blake R. Hossack ◽

Winsor H. Lowe ◽

R. Ken Honeycutt ◽

Sean A. Parks ◽

Paul Stephen Corn

Keyword(s):

Forest Management ◽

Interactive Effects ◽

Parasite Abundance

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Interactive effects of a non-native invasive grassMicrostegium vimineumand herbivore exclusion on experimental tree regeneration under differing forest management

Journal of Applied Ecology ◽

10.1111/1365-2664.12356 ◽

2014 ◽

Vol 52 (1) ◽

pp. 210-219 ◽

Cited By ~ 11

Author(s):

Daniel J. Johnson ◽

S. Luke Flory ◽

Angela Shelton ◽

Cynthia Huebner ◽

Keith Clay

Keyword(s):

Forest Management ◽

Tree Regeneration ◽

Interactive Effects ◽

Herbivore Exclusion ◽

Native Invasive

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Interactive effects of past land use and recent forest management on the understorey community in temperate oak forests in South Sweden

Journal of Vegetation Science ◽

10.1111/jvs.12770 ◽

2019 ◽

Vol 30 (5) ◽

pp. 917-928 ◽

Cited By ~ 8

Author(s):

Leen Depauw ◽

Michael P. Perring ◽

Jörg Brunet ◽

Sybryn L. Maes ◽

Haben Blondeel ◽

...

Keyword(s):

Land Use ◽

Forest Management ◽

Interactive Effects ◽

Oak Forests ◽

South Sweden ◽

Past Land Use

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Assessment of long term interaction between the endemic seagrass P. oceanica and the exotic green alga C. cylindracea in the South Eastern coast of Spain (Murcia Region)

10.7287/peerj.preprints.1065v1 ◽

2015 ◽

Author(s):

Jaime Bernardeau-Esteller ◽

Rocio García-Muñoz ◽

Lázaro Marín-Guirao ◽

Jose Miguel Sandoval-Gil ◽

Ruiz Juan Fernandez

Keyword(s):

Green Alga ◽

Algal Growth ◽

Interactive Effects ◽

Limiting Factors ◽

Eastern Coast ◽

Future Research ◽

The South ◽

South Eastern ◽

Leaf Canopy

The green alga Caulerpa cylindracea has rapidly spread throughout the Western Mediterranean during the last 20 years. Compared with other native benthic communities, Posidonia oceanica meadows seems to be highly resistant to the colonization by the alga. Nonetheless, it is suggested that in the long-term C. cylindracea could affect the seagrass altering its vitality, structure and functions, however little is known about the interactive effects between these two structuring species. To this end, the abundance of both macrophytes was quantified and monitored in invaded and non-invaded localities of the South Eastern coast of Spain (Murcia Region) over an 8-year period (2007-2014). Results indicate that no differences were highlighted between invaded and no invaded meadows and all the monitored meadows showed stable or progressive trends in shoot density, meadow cover and net population growth. Regardless of the depth, in all of the invaded localities C. cylindracea biomass present inside the seagrass leaf canopy was about 10 to 50–fold lower than that measured just outside the leaf canopy. In summary, our results do not support the existence of a long-term competitive interaction between the invasive alga and the native seagrass, at least in the studied meadows and at the meadow level. C. cylindracea forms huge biomass gradients associated to the seagrass meadow edges that are stable with time, which suggests the existence of highly limiting conditions for algal growth and survival under the P. oceanica leaf canopy. Future research on such limiting factors could help us to understand the invasive capacity of the alga and the factors involved in the resistance of native habitats to bioinvasions.

Download Full-text