Modelling the distribution and density of the invasive seaweed Sargassum muticum (Fucales, Sargassaceae) in shallow subtidal areas

The present study describes the distribution and density of Sargassum muticum in shallow subtidal areas of the Marine Fishery Reserve (MFR) ‘Os Miñarzos’ (Galicia, north-western Spain) by using a data-collection strategy and a statistical approach fairly unused in literature. Our surveys showed a rapid spread of the invasive alga in the study area, where the number of patches increased more than 50% between 2008 and 2009. A model-selection approach was used to test the goodness of fit of Sargassum density data and the zero-inflated Poisson (ZIP) appeared to be the best model. The ZIP model quantified a probability of 22% of finding at least one Sargassum plant in a randomly placed quadrat within 11-m depth, demonstrating that a large part of the MFR has been invaded. In particular, the ZIP model showed that season, richness of macroalgal community, and abiotic factors, such as wave exposure and depth, are essential drivers for the establishment of S. muticum thalli in subtidal areas. Our results showed that the invasion of subtidal areas often follows patterns similar to the intertidal areas. The present study also demonstrated the usefulness of zero-inflated models to assess early and mid-stages of a seaweed invasion.

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Enhancing Methane Production from Spring-Harvested Sargassum muticum

Springer Proceedings in Energy - Energy and Sustainable Futures ◽

10.1007/978-3-030-63916-7_15 ◽

2021 ◽

pp. 117-123

Author(s):

Supattra Maneein ◽

John J. Milledge ◽

Birthe V. Nielsen

Keyword(s):

Anaerobic Digestion ◽

Pharmaceutical Industry ◽

Brown Seaweed ◽

Sargassum Muticum ◽

Biofuel Production ◽

Biochemical Methane Potential ◽

Seaweed Species ◽

Invasive Seaweed ◽

Methane Potential ◽

Aqueous Meoh

AbstractSargassum muticum is a brown seaweed which is invasive to Europe and currently treated as waste. The use of S. muticum for biofuel production by anaerobic digestion (AD) is limited by low methane (CH4) yields. This study compares the biochemical methane potential (BMP) of S. muticum treated in three different approaches: aqueous methanol (70% MeOH) treated, washed, and untreated. Aqueous MeOH treatment of spring-harvested S. muticum was found to increase CH4 production potential by almost 50% relative to the untreated biomass. The MeOH treatment possibly extracts AD inhibitors which could be high-value compounds for use in the pharmaceutical industry, showing potential for the development of a biorefinery approach; ultimately exploiting this invasive seaweed species.

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The Effects of the Invasive Seaweed Asparagopsis Armata on Native Rock Pool Communities: Evidences from Experimental Exclusion

10.20944/preprints202010.0089.v1 ◽

2020 ◽

Cited By ~ 1

Author(s):

Carla Silva ◽

Marco Lemos ◽

Rui Gaspar ◽

Carlos Gonçalves ◽

João Neto

Keyword(s):

Algal Species ◽

Taxonomic Composition ◽

Habitat Destruction ◽

Rock Pools ◽

Red Macroalgae ◽

Invasive Seaweed ◽

Shallow Subtidal ◽

Intertidal Seaweed ◽

Macroalgal Assemblage ◽

Asparagopsis Armata

Biological invasions represent a threat to ecosystems, through competition and habitat destruction, which may result in significant changes of the invaded community. Asparagopsis armata is a red macroalgae (Rodophyta) globally recognized as an invasive species. It is found from the intertidal to shallow subtidal areas, on rock or epiphytic, forming natural vegetation belts on exposed coasts. This study evaluated the variations on native intertidal seaweed and macroinvertebrate assemblages inhabiting rock pools with and without the presence of the invasive macroalgae A. armata. To achieve this, manipulation experiments on Atlantic (Portugal) rock pools were done. Three rock pools were maintained without A. armata by manual removal of macroalgae, and three others were not experimentally manipulated during the study period and A. armata was freely present. In this study the variations between different rock pools were assessed. Results showed different patterns in the macroalgae composition of assemblages but not for the macrobenthic communities. Ellisolandia elongata was the main algal species affected by the invasion of A. armata. Invaded pools tended to show less species richness, showing a more constant and conservative structure, with lower variation of its taxonomic composition than the pools not containing A. armata, where the variability between samples was always higher. Despite the importance of the achieved results, further data based on observation of long-term series are needed, in order to further understand more severe effects of the invader A. armata on native macroalgal assemblage.

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The trophic significance of the invasive seaweed Sargassum muticum in sandy beaches

Journal of Sea Research ◽

10.1016/j.seares.2009.09.005 ◽

2010 ◽

Vol 63 (1) ◽

pp. 52-61 ◽

Cited By ~ 17

Author(s):

Francesca Rossi ◽

Celia Olabarria ◽

Mónica Incera ◽

Josefina Garrido

Keyword(s):

Sandy Beaches ◽

Sargassum Muticum ◽

Invasive Seaweed

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Macrobenthic fauna in the Ensenada de San Simón (Galicia, north-western Spain)

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315408000660 ◽

2008 ◽

Vol 88 (2) ◽

pp. 237-245 ◽

Cited By ~ 10

Author(s):

E. Cacabelos ◽

L. Gestoso ◽

J. Troncoso

Keyword(s):

Grain Size ◽

Qualitative Composition ◽

Zostera Noltii ◽

Intertidal Sediments ◽

Macrobenthic Fauna ◽

Shallow Subtidal ◽

Soft Bottoms ◽

Characteristic Species ◽

Western Spain ◽

North Western

Distribution and abundance of the macrobenthic fauna was studied in the intertidal and subtidal soft-bottoms of the Ensenada de San Simón (north-western Spain). Depth and grain size were the most important factors in determining patterns of distribution of the macrozoobenthos. A reduced Macoma community was present in the inner area of the inlet structured in two facies subdivision in the community that does not affect its qualitative composition: the first one was in intertidal areas associated with meadows of the sea grasses Zostera noltii and Z. marina and defined by the dominance of Hydrobia ulvae; the second facies in intertidal sediments was characterized by the dominance of Tubificidae and nematodes and Pseudopolydora paucibranchiata. The poverty of these bottoms in number of species can be due to salinity fluctuations and human activities developed in the area. Subtidal bottoms were characterized by a Syndosmya(=Abra)alba community. Two facies were detected: one facies located in shallow subtidal bottoms with H. ulvae and Thyasira flexuosa as characteristic species, and a second facies in deeper areas, characterized by the polychaetes Ampharete finmarchica, P. paucibranchiata, Aphelochaeta marioni, Melinna palmata and Paradoneis lyra.

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Remarkable differences in the presence of the acanthocephalan parasite Echinorhynchus truttae in brown trout (Salmo trutta) captured in two adjacent river basins in Galicia (NW Spain)

Parasitology Open ◽

10.1017/pao.2017.24 ◽

2018 ◽

Vol 4 ◽

Author(s):

Seila Couso-Pérez ◽

Antonio Cañizo-Outeiriño ◽

Rainer Campo-Ramos ◽

Elvira Ares-Mazás ◽

Hipólito Gómez-Couso

Keyword(s):

Brown Trout ◽

Salmo Trutta ◽

Anthropogenic Activities ◽

Abiotic Factors ◽

River Basins ◽

Brown Trout Salmo Trutta ◽

Western Spain ◽

Acanthocephalan Parasite ◽

North Western ◽

Crustacean Host

Abstract This is the first report on the presence of acanthocephalan parasite Echinorhynchus truttae in brown trout (Salmo trutta) from Spain. A total of 343 fish were captured by local anglers from 19 rivers in the adjacent Tambre and Ulla watersheds in Galicia (north-western Spain). Macroscopic and microscopic analyses of the intestinal contents revealed the presence of adults and/or eggs of E. truttae in 53 of the 123 trout from Tambre river basin (43.1%). By contrast, parasitic forms of this acanthocephalan were only observed in eight of the 220 fish from Ulla basin (3.6%), showing significant differences between the prevalences obtained in two adjacent watersheds (P < 0.001, odds ratio 19.0). Prevalence was significantly higher in specimens >3 years (length >26.0 cm) than in younger specimens (P < 0.05). The absence of Gammarus pulex in the region suggests that native gammarid species in Galicia (Echinogammarus lusitanicus and Echinogammarus beriyoni) may act as intermediate host in the life cycle of E. truttae. Different prevalences of E. truttae indicate that the presence/abundance of the intermediate crustacean host may be different in the two river basins, probably as a consequence of various abiotic factors and anthropogenic activities.

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Assessing site form as an indicator of site quality in even-aged Pinus radiata D. Don stands in north-western Spain

Annals of Forest Science ◽

10.1007/s13595-019-0904-1 ◽

2019 ◽

Vol 76 (4) ◽

Cited By ~ 1

Author(s):

Juan Alberto Molina-Valero ◽

Ulises Diéguez-Aranda ◽

Juan Gabriel Álvarez-González ◽

Fernando Castedo-Dorado ◽

César Pérez-Cruzado

Keyword(s):

Pinus Radiata ◽

Goodness Of Fit ◽

Model Fitting ◽

Site Index ◽

Site Quality ◽

Stand Age ◽

Fit Statistics ◽

Dominant Height ◽

Western Spain ◽

North Western

Abstract Key message Site form and site index have shown similar precision for estimating site quality in even-agedPinus radiataD. Don stands in north-western Spain. Additionally, SF presents the advantage that it does not require stand age information and can therefore be used in a wider set of situations in the forestry practice. Context Estimation of site quality is essential for characterizing, monitoring and predicting forest resources. Site index (i.e. the dominant height of the stand at a reference age) is ordinarily used to estimate site quality; however, this index is only useful for even-aged stands of known age. By contrast, SF is age-independent as it uses the dominant height of the stand at a reference dominant diameter. Aims The aim of this study was to compare the performance of SF and SI for site quality estimation in even-aged P. radiata stands. Methods Dynamic equations derived with the Generalized Algebraic Difference Approach (GADA) from the Hossfeld IV base model were fitted to predict site quality with both SI and SF. SF predictions were compared with SI regarding variability within the same plot and consistency in site quality predictions, using the observed maximum mean annual volume increment (MAI) as a direct measure of site quality. Results Both approaches showed good performance in model fitting and provided similar goodness-of-fit statistics and variability in the predictions. However, SI performed slightly stronger when related to MAI. Conclusion SF performed adequately in estimating site quality for even-aged P. radiata stands, with results comparable to those obtained using traditional SI.

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Bioenvironmental characteristics of Robinia pseudoacacia steppe plantations in dependence to changes in some climatic factors

Питання степового лісознавства та лісової рекультивації земель ◽

10.15421/442101 ◽

2021 ◽

Vol 50 ◽

pp. 3-11

Author(s):

L. V. Dotsenko ◽

V. I. Chorna ◽

Yu. I. Hrytsan ◽

N. V. Voroshylova ◽

V. V. Katsevych

Keyword(s):

Climatic Factors ◽

Abiotic Factors ◽

Robinia Pseudoacacia ◽

Great Majority ◽

Tree Plantations ◽

Limiting Factor ◽

Age Composition ◽

Plant Associations ◽

Precipitation Decrease ◽

Rapid Spread

Сlimatic factors play the most important role in the plant associations formation. Sunlight is one of the leading factors that determine the appearance of a particular community and very often plays the limiting factor role. In the conditions of the Steppe Dnipro Region, its limiting role can be expressed only in its excess. The great majority of autochthonous steppe flora plant species has strongly pronounced adaptations to excessive solar insolation. With the development of forest biogeocenology and steppe forestry, more and more attention is paid to the issues of forest climatology. It is shown that climatic factors have an imperative effect on the formation of soils, plant associations, fauna and ecosystems in general. Artificial plantations consisting of fast-growing hardwoods, such as Robinia pseudoacacia, have been studied. The complex of abiotic factors in robinia plantations and in open areas has its own characteristics. The processes of reflection, transformation and accumulation of solar energy in tree plantations have a slightly different character than in forest-free areas. In the Dnipropetrovsk region, the populations of Robinia pseudoacacia are represented mainly by young plants that have already entered the phase of active fruiting. No plants older than 100 years were found in the populations. Thus, the price spectrum of the age composition of the population of Robinia pseudoacacia in the Dnipropetrovsk region has a pronounced left-sided character, ie shifted towards young individuals that are actively fruiting. This indicates that the processes of expansion of Robinia pseudoacacia to natural biogeocenoses will be actively continued. Despite the fact that this breed has a number of positive qualities (excellent medonis, root mycorrhiza with azotobacter, high gas resistance, etc.), the processes of uncontrolled active settlement of this species is a matter of serious concern. This breed is capable of rapid spread and disruption of successional processes occurring in the area. In the conditions of the forecasted climate changes towards temperature increase and precipitation decrease this breed receives more and more advantages.

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Chemical Control of Corythucha arcuata (Say, 1832), an Invasive Alien Species, in Oak Forests

Forests ◽

10.3390/f12060770 ◽

2021 ◽

Vol 12 (6) ◽

pp. 770

Author(s):

Flavius Bălăcenoiu ◽

Constantin Nețoiu ◽

Romică Tomescu ◽

Dieter Carol Simon ◽

Andrei Buzatu ◽

...

Keyword(s):

Alien Species ◽

Invasive Alien Species ◽

Abiotic Factors ◽

Systemic Insecticide ◽

Lace Bug ◽

Oak Trees ◽

Rapid Spread ◽

Treatment Volume ◽

Low Volume ◽

Insecticide Sprays

In addition to the classic biotic and abiotic factors that have disrupted the health of forests throughout history, lately, the balance of forest ecosystems has been disturbed by different phenomena such as climate change, pollution, and, especially, biological invasions of invasive alien species. One of the alien species that has invaded Europe relatively quickly is an insect species of North American origin, the oak lace bug (Corythucha arcuata Say, 1832 Heteroptera: Tingidae). In the context of the rapid spread of infestations and the severity of attacks on oak trees in infested forests, this paper aims to assess measures to manage this species in the future. Namely, the effect of aerial chemical treatments on oak lace bug has been investigated with two influencing factors: the mode of insecticide action (contact and systemic) and the treatment volume (low volume and ultra-low volume). The experiment was conducted in two forests over a total area of 350 hectares. The results show that the reduction of the nymph population varied from 91% to 96%. However, the residual population was sufficient to allow differentiated re-infestations over time, more quickly after contact insecticide sprays (22 days after treatment) and slowly after systemic insecticide sprays (more than a month after treatment). This re-infestation time difference had implications on attack intensity as well, with stronger leaf discoloration observed in areas treated with a contact insecticide compared with those treated with a systemic insecticide.

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