scholarly journals Metabolism of a subtidal rocky mussel reef in a high-temperate setting: pathways of organic C flow

2020 ◽  
Vol 645 ◽  
pp. 41-54 ◽  
Author(s):  
KM Attard ◽  
IF Rodil ◽  
P Berg ◽  
AOM Mogg ◽  
M Westerbom ◽  
...  
Keyword(s):  
Light Intensity ◽  
Baltic Sea ◽  
Food Supply ◽  
Gross Primary Production ◽  
Abundant Species ◽  
Mytilus Trossulus ◽  
Organic C ◽  
Transport And Transformation ◽  
Eddy Fluxes

Mytilid mussels form abundant, species-rich reefs on rocky substrates, but the role of this key habitat in carbon (C) cycling remains poorly understood. We performed a seasonal study on a 5 m deep photic Mytilus trossulus reef in the Central Baltic Sea to investigate pathways and rates of organic C flow. Reef gross primary production (GPP) and respiration (R) were estimated seasonally using underwater O2 eddy covariance on hourly and daily timescales. Photogrammetry and biotic sampling were used to quantify reef rugosity and mussel coverage, and to derive mussel filtration and biodeposition. Mussels were highly abundant, reaching ~50000 ind. m-2, and the reef structure increased the seabed surface area by 44%. GPPhourly was up to 20 mmol O2 m-2 h-1 and GPPdaily was up to 107 mmol O2 m-2 d-1, comparable to a nearby seagrass canopy. Hourly eddy fluxes responded linearly to light intensity and flow velocity, with higher velocities enhancing reef O2 uptake at night. Reef Rdaily exceeded GPPdaily on 12 of 13 measurement days, and Rannual (29 mol O2 m-2 yr-1) was 3-fold larger than GPPannual. The reef sustained a productive community of microbes and fauna whose activities accounted for ~50% of Rannual. Horizontal water advection promoted food supply to the reef and likely facilitated substantial lateral C export of mussel biodeposits. Our analyses suggest that a reduction in mussel reef extent due to ongoing environmental change will have major implications for the transport and transformation of C and nutrients within the coastal Baltic Sea.

scholarly journals Mosquito Vector Production across Socio-Economic Divides in Baton Rouge, Louisiana

2021 ◽  
Vol 18 (4) ◽  
pp. 1420
Author(s):  
Rebeca de Jesús Crespo ◽  
Madison Harrison ◽  
Rachel Rogers ◽  
Randy Vaeth
Keyword(s):  
Low Income ◽  
Baton Rouge ◽  
Habitat Preferences ◽  
Abundant Species ◽  
Mosquito Larvae ◽  
Mosquito Vector ◽  
Mosquito Vectors ◽  
Low Income Groups ◽  
Socio Economic Factors

We investigated the role of socio-economic factors in the proliferation of mosquito vectors in two adjacent but socio-economically contrasting neighborhoods in Baton Rouge, LA, USA. We surveyed mosquito larvae habitat, mosquito larvae, and adult mosquitoes during the summer of 2020. We also evaluated the number of requests for mosquito abatement services in the years preceding the study for each area. While we did not find differences in terms of the most abundant species, Culex quinquefasicatus (F1,30 = 0.329, p = 0.57), we did find a higher abundance of mosquito habitats, particularly discarded tires, as well as larvae (z = 13.83, p < 0.001) and adults (F1,30 = 4.207, p = 0.049) of the species Aedes albopictus in the low-income neighborhood. In contrast, mosquito abatement requests were significantly higher in the high socio-economic neighborhood (z = −8.561, p < 0.001). This study shows how factors such as adjudicated properties, discarded tires and pest abatement requests can influence the abundance of mosquito vectors, disproportionately affecting low-income groups. This study also highlights how Aedes spp. may be better indicators than Culex spp. of socio-economic differences between nearby neighborhoods, due to their short flight range and habitat preferences, and this should be considered in future studies attempting to detect such disparities in the future.

scholarly journals Species functional traits and abundance as drivers of multiplex ecological networks: first empirical quantification of inter-layer edge weights

2020 ◽  
Vol 287 (1939) ◽  
pp. 20202127
Author(s):  
S. Hervías-Parejo ◽  
C. Tur ◽  
R. Heleno ◽  
M. Nogales ◽  
S. Timóteo ◽  
...  
Keyword(s):  
Species Traits ◽  
Abundant Species ◽  
Modular Organization ◽  
Vertebrate Species ◽  
Multilayer Network ◽  
Functional Roles ◽  
Different Types ◽  
Seed Dispersers ◽  
Natural Communities

Many vertebrate species act as both plant pollinators and seed-dispersers, thus interconnecting these processes, particularly on islands. Ecological multilayer networks are a powerful tool to explore interdependencies between processes; however, quantifying the links between species engaging in different types of interactions (i.e. inter-layer edges) remains a great challenge. Here, we empirically measured inter-layer edge weights by quantifying the role of individually marked birds as both pollinators and seed-dispersers of Galápagos plant species over an entire year. Although most species (80%) engaged in both functions, we show that only a small proportion of individuals actually linked the two processes, highlighting the need to further consider intra-specific variability in individuals' functional roles. Furthermore, we found a high variation among species in linking both processes, i.e. some species contribute more than others to the modular organization of the multilayer network. Small and abundant species are particularly important for the cohesion of pollinator seed-dispersal networks, demonstrating the interplay between species traits and neutral processes structuring natural communities.

scholarly journals Casting Activity ofScherotheca gigasin No-Till Mediterranean Soils: Role in Organic Matter Incorporation and Influence of Aridity

2010 ◽  
Vol 2010 ◽  
pp. 1-6 ◽  
Author(s):  
Paloma Bescansa ◽  
Iñigo Virto ◽  
Oihane Fernández-Ugalde ◽  
María José Imaz ◽  
Alberto Enrique
Keyword(s):  
Organic Matter ◽  
Agricultural Soils ◽  
Nw Spain ◽  
Organic C ◽  
No Till ◽  
Physico Chemical ◽  
C Stocks ◽  
Casting Activity ◽  
Total Organic C

The behaviour of earthworms, their role in organic matter incorporation into the soil, and the influence of aridity in such processes in arid and semiarid regions have scarcely been studied. In this study, physico-chemical analyses of the casts and the surrounding no-till agricultural soils of three experimental sites representing an aridity gradient in Navarre (NW Spain) were done. The casts were formed by the activity of the only anecic species,Scherotheca gigas(Dugès, 1828), ubiquitous in no-till soils in this region. We observed a significant depletion of clay and higher concentration of total organic C and labile C in the form of particulate organic matter (POM) in the casts as compared to the surrounding soil, suggesting selective ingestion of soil byS. gigas. This, together with the observation of increased concentration in POM with increasing aridity, suggests a major role of this species in the observed progressive gains of organic C stocks in no-till soils in the region.

Influence of soil organic matter on sulfate retention in two Podzols in Quebec, Canada

1999 ◽  
Vol 79 (1) ◽  
pp. 103-109 ◽  
Author(s):  
F. Courchesne ◽  
J.-F. Laberge ◽  
A. Dufresne
Keyword(s):  
Organic Matter ◽  
Soil Organic Matter ◽  
Ammonium Oxalate ◽  
X Ray Diffraction ◽  
Weighted Mean ◽  
Fine Silt ◽  
Mineral Horizon ◽  
Organic C ◽  
X Ray

The role of soil organic matter (OM) on SO4 retention was investigated by comparing OM content, SO4 retention, and the distribution of Fe, Al and Si compounds in OM-poor (Grands-Jardins, PGJ) and OM-rich (Hermine, HER) Podzols from Québec, Canada. At both sites, four pedons were sampled by horizon; soil pH in H2O, organic C, phosphate-extractable SO4 and, sodium pyrophosphate, acid ammonium oxalate and dithionite-citrate-bicarbonate (DCB) extractable Fe, Al and Si were measured for each mineral horizon. The mineralogy of the clay (<2 µm) and fine silt (2–20 µm) fractions of selected horizons was determined by X-ray diffraction (XRD) and infrared spectroscopy (IR). Weighted mean organic C and pyrophosphate extractable Fe and Al contents were significantly higher in the HER than in the PGJ sola, while the PGJ soils were richer in amorphous inorganic Al. No trends were observed for inorganic Fe compounds. Chemical dissolution and IR allowed the identification of short-range ordered aluminosilicates, probably allophane, in the OM-poor and slightly acidic to neutral PGJ soils. These materials were absent from the OM-rich and acidic HER soils. Phosphate extractions showed that the weighted mean native SO4 content was five times higher in the PGJ than in the HER soil. Finally, native SO4 was strongly related to inorganic Fe, Al and Si (associated with allophane) at PGJ but only to inorganic Fe at HER. These results indicate that OM indirectly affects SO4 sorption through the influence organic substances exerts on the nature and distribution of pedogenic Fe, Al and Si compounds, such as allophane, in Podzolic profiles. Key words: Organic matter, sulfate, imogolite, allophane, silica, Podzol

The role of light intensity in mediating ascorbic acid content during postharvest tomato ripening: A transcriptomic analysis

2021 ◽  
Vol 180 ◽  
pp. 111622
Author(s):  
Yating Zhang ◽  
Nikolaos Ntagkas ◽  
Dimitrios Fanourakis ◽  
Georgios Tsaniklidis ◽  
Jiantao Zhao ◽  
...  
Keyword(s):  
Ascorbic Acid ◽  
Light Intensity ◽  
Acid Content ◽  
Ascorbic Acid Content ◽  
Transcriptomic Analysis ◽  
Role Of Light

The Role of Binary and Ion Nucleation of Sulfuric Acid and Water Vapor in the Dynamics of Sulfate Aerosol Formation in the Atmosphere

2021 ◽  
pp. 53-60
Author(s):  
A. E. Aloyan ◽  
◽  
A. N. Yermakov ◽  
V. O. Arutyunyan ◽  
◽  
...  
Keyword(s):  
Water Vapor ◽  
Sulfuric Acid ◽  
Three Dimensional ◽  
Ionization Rate ◽  
Sulfate Aerosol ◽  
Aerosol Formation ◽  
Three Dimensional Model ◽  
Aerosol Composition ◽  
Transport And Transformation

The results of one-dimensional calculations of the height profiles of nucleated sulfate aerosol particles for the northern mid-latitudes and tropics in winter are presented. Numerical calculations were performed using a three-dimensional model of the transport and transformation of multicompo- nent gas and aerosol substances in the atmosphere, incorporating photochemistry, nucleation involving neutral molecules and ions, as well as condensation/evaporation and coagulation. It is found that the resulting dynamics of the formation of aerosol particle nuclei is not a simple sum of ion and binary (water vapor/sulfuric acid) nucleation rates. This dynamics is determined by the ratio of critical radii of nucleated particles due to binary and ion nucleation of these substances (rcr_bin and rcr_ion) depending on temperature, relative humidity, and ionization rate. This should be taken into account in modeling the gas and aerosol composition of the atmosphere and comparing calculated and observed data.

scholarly journals Siphonophora from the coast of Brazil (17ºS to 24ºS)

1991 ◽  
Vol 39 (1) ◽  
pp. 61-69 ◽  
Author(s):  
Catarina Ramis Nogueira ◽  
Sérgio dos Reis Oliveira Jr
Keyword(s):  
East Coast ◽  
Coastal Upwelling ◽  
Mesh Size ◽  
Abundant Species ◽  
Factorial Analysis ◽  
The Other ◽  
Trophic Interaction ◽  
Principal Axes ◽  
Bank System

This work is based on the analysis of 99 zooplankton samples collected during the Oceanographic Expedition "ESPÍRITO SANTO I", held along the east coast of Brazil, between Cabo Frio and Abrolhos Archipelago, an area characterized by the occurrence of coastal upwelling, from July to September 1984. Zooplankton was collected with vertical plankton net hauls of 250 µm mesh size in the upper 200 meters layer. A total of twenty one species of Siphonophora was observed, two of which were identified as being physonect and the other as calycophorans. Specific diversity close to the shore and at the neighborhood of the Vitória-Trindade Bank System, showed smaller values, in comparison with those in the oceanic regions. Factorial analysis was used in order to access the changes observed in the population of the eleven most abundant species. The first two principal axes represented the influence of the nearshore - offshore gradient and the role of trophic interaction, accounted for 60% of the total variance of the data.

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