The Influence of the Chemical Composition of Typha Domingensis and Nymphaea Ampla Detritus on Invertebrate Colonization During Decomposition in a Brazilian Coastal Lagoon

The aim of this study was to evaluate methane concentration in water column and pore water at limnetic and littoral regions of a coastal lagoon. At the littoral region samples were taken from three monospecific macrophytes stands (Typha domingensis, Eleocharis interstincta and Potamogeton stenostachys). The methane concentration in the pore water at the littoral region was higher than the concentration found at the limnetic region in each fraction of the sediment. The higher methane concentration in the superficial fraction of the sediment (0-2 cm) was shown at the P. stenostachys stand (3.7 mM). It was the only significantly different (p<0.05) from the limnetic region. The pore water methane concentration increased with depth at the aquatic macrophytes stands. The methane concentration in the water column did not vary significantly among the sampling sites (p>0.05). It could be concluded that there was a high influence of aquatic macrophytes on the pore water methane concentration.

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Succession and diversity of Chironomidae in detritus of Typha domingensis in a coastal lagoon (Parque Nacional da Restinga de Jurubatiba, State of Rio de Janeiro, Brazil)

SIL Proceedings 1922-2010 ◽

10.1080/03680770.1998.11901665 ◽

2000 ◽

Vol 27 (4) ◽

pp. 2374-2377

Author(s):

J. F. Gonçalves ◽

F. A. Esteves ◽

M. Callisto

Keyword(s):

Coastal Lagoon ◽

Rio De Janeiro ◽

Typha Domingensis

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Chemical change of leaves during breakdown affects associated invertebrates in a subtropical stream

Acta Limnologica Brasiliensia ◽

10.1590/s2179-975x2014000300003 ◽

2014 ◽

Vol 26 (3) ◽

pp. 235-244 ◽

Cited By ~ 1

Author(s):

Alan Mosele Tonin ◽

Rozane Maria Restello ◽

Luiz Ubiratan Hepp

Keyword(s):

Regression Analysis ◽

Chemical Composition ◽

Chemical Change ◽

Total Density ◽

Riparian Ecosystems ◽

Biological Communities ◽

Colonization Process ◽

Subtropical Stream ◽

The Relationship ◽

Invertebrate Colonization

AIMS: Our objective was assess the effects of leaf chemical change during breakdown on the associated invertebrates. METHODS: We evaluate the chemical composition of leaves (of two tree species; Sebastiania brasiliensis and Campomanesia xanthocarpa) and the density of invertebrates during leaf breakdown (on four incubation times; 3, 7, 14 and 22 days) in a subtropical stream. Linear multiple regression analysis were performed to evaluate the relationship between invertebrate density and changes in leaf chemical during breakdown. RESULTS: Density of invertebrates was related to the chemical composition of leaves. There was a positive correlation of K (β = 3.48) and a negative of C:N (β = -0.34), polyphenols (β = -0.16), Ca (β = -2.98) and Mg (β = -2.58) with the total density of invertebrates. Density of invertebrates on leaves reached 38 ± 9 and 192 ± 31 individuals g-1 leaf DM during the first 3 and 7 days of incubation, had decreased by the 14th day (117 ± 18) and then increased after 22 days (270 ± 41). CONCLUSIONS: We conclude that changes in the chemistry of decomposing leaves affect invertebrate colonization process. This conclusion reinforce the importance of understand the dynamic of energy and nutrients and its association with the biological communities of tropical riparian ecosystems.

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The Origin of the Moon

Symposium - International Astronomical Union ◽

10.1017/s0074180900178209 ◽

1962 ◽

Vol 14 ◽

pp. 149-155 ◽

Cited By ~ 1

Author(s):

E. L. Ruskol

Keyword(s):

Chemical Composition ◽

Solar System ◽

The Moon ◽

The Earth ◽

The Difference ◽

Origin Of The Moon

The difference between average densities of the Moon and Earth was interpreted in the preceding report by Professor H. Urey as indicating a difference in their chemical composition. Therefore, Urey assumes the Moon's formation to have taken place far away from the Earth, under conditions differing substantially from the conditions of Earth's formation. In such a case, the Earth should have captured the Moon. As is admitted by Professor Urey himself, such a capture is a very improbable event. In addition, an assumption that the “lunar” dimensions were representative of protoplanetary bodies in the entire solar system encounters great difficulties.

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On the Inhomogeneity of Chemical Composition over the Surface of 21 Per

International Astronomical Union Colloquium ◽

10.1017/s0252921100080659 ◽

1976 ◽

Vol 32 ◽

pp. 343-349

Author(s):

Yu.V. Glagolevsky ◽

K.I. Kozlova ◽

V.S. Lebedev ◽

N.S. Polosukhina

Keyword(s):

Chemical Composition ◽

Spectral Line ◽

Variable Star ◽

Radial Velocities ◽

Crimean Astrophysical Observatory ◽

Line Intensities ◽

Magnetic Variable

SummaryThe magnetic variable star 21 Per has been studied from 4 and 8 Å/mm spectra obtained with the 2.6 - meter reflector of the Crimean Astrophysical Observatory. Spectral line intensities (Wλ) and radial velocities (Vr) have been measured.

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Structural Studies on Mitotic Spindle Fibres

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100070345 ◽

1978 ◽

Vol 36 (3) ◽

pp. 615-626

Author(s):

J.R. Mcintosh

Keyword(s):

Chemical Composition ◽

Mitotic Spindle ◽

Structural Studies ◽

Mitotic Apparatus ◽

Chemical Studies ◽

Medical Interest ◽

Spindle Fibres

The mitotic apparatus is a structure of obvious biological and medical interest, but it has proved to be a difficult cellular machine to understand. The chemical composition of the spindle is only slightly elucidated, largely because of the difficulties in preparing useful isolates of the structure. Chemical studies of the mitotic spindle have been reviewed elsewhere (Mcintosh, 1977), and will not be discussed further here. One would think that structural studies on the mitotic apparatus (MA) in situ would be straightforward, but even with this approach there is some disagreement in the results obtained with various methods and by different investigators. In this paper I will review briefly the approaches which have been used in structural studies of the MA, pointing out the strengths and problems of each approach. I will summarize the principal findings of the different methods, and identify what seem to be fruitful avenues for further work.

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