scholarly journals Differences in the decomposition of green and senescent leaves in streams of Reserva Florestal Adolpho Ducke (Amazonas, Brazil)

2018 ◽  
Vol 12 (01) ◽  
pp. 1-10
Author(s):  
Bianca Maíra de Paiva Ottoni-Boldrini

Leaves are considered the main energetic resource supply among all the allochthonous organic material available for the small shaded streams. However, their processing is limited by the physical and chemical characteristics of the leaves. Therefore, this research aimed to: i) evaluate the difference in decomposition coefficients between green and senescent leaves; ii) compare richness and density of aquatic invertebrates colonizing decomposing green and senescent leaves.  Between November 2012 and January 2013, 12 leaf packages (6 senescent and 6 green) of 14 plant species were installed in 3 streams of the Reserva Florestal Adolpho Ducke (Manaus/AM - Brazil). After 15, 30 and 60 days the submerged packages were removed. The collected material was taken to the laboratory for analyzes of: aquatic invertebrates and leaves' mass remnants. Paired t-test was performed to verify if the decomposition coefficients (k) differed. ANCOVAs were performed to compare: the remaining mass (%), richness and density of aquatic invertebrates between leaf type over time. The green leaves presented higher leaf decomposition rates than in senescent ones. The leaf type influenced the average invertebrates densities. Therefore, green leaves were more susceptible to the colonization of aquatic invertebrates associated with the leaf decomposition process in small Amazonian streams. 

1978 ◽  
Vol 50 (3) ◽  
pp. 276-284
Author(s):  
Maija-Liisa Salo

61 samples of barley with a volume weight of 38—75 kg/hl, and 49 oat samples with a volume weight of 40—65kg/hl were analyzed for physical and chemical characteristics. The approximate metabolizable energy (ME) value was calculated from the composition. The physical characteristics varied more, but the starch content less, in barley than in oats. There was also a negative correlation between starch and crude protein, and ether extract level in barley, but not in oats. Therefore the difference between the ME values of the best and the poorest samples was only 12% for barley, but 27 % for oats. Both the starch and the crude protein content predicted the ME value well: R2 of starch was 78—94 %, and that of crude fibre 55—84 %. The volume weight still gave a good indication for barley, but not at all for oats.


1983 ◽  
Vol 34 (5) ◽  
pp. 537 ◽  
Author(s):  
JR Donnelly ◽  
FHW Morley ◽  
GT McKinney

Spring-lambing Merino and crossbred ewes grazing on dryland lucerne pastures were generally heavier throughout the year than ewes grazing on phalaris and subterranean clover pastures, even though they experienced greater weight losses during winter. These losses were mostly eliminated by compensatory gains in spring. Annual fleece weights of the Merino ewes grazing on lucerne or phalaris and subterranean clover pastures declined linearly by 146 and 64 g respectively for each additional ewe carried over a range of stocking rates from 9 to 18 ha-1. Corresponding figures for crossbred ewes were 114 and 46 g. In each case the difference between pasture species was significant (P < 0.02). Only at the lowest stocking rates were fleeces from ewes on lucerne heavier (by c. 500 g) than those from ewes on phalaris. At the highest stocking rates, there were no advantages in terms of wool production from grazing breeding ewes on lucerne. Not only was there a greater need for supplementary feed during late pregnancy to avoid losses from pregnancy toxaemia, but the lucerne pastures at all stocking rates proved more sensitive to unfavourable physical and chemical characteristics of soils than did phalaris and subterranean clover pastures. The fleece weights of Merino and crossbred ewes declined, on average, by 70 and 50 g per year for ewes aged between 1+ and 6+ years. Pregnancy reduced fleece weights by 5-10% in Merinos and 5-21% in crossbred ewes, depending on seasonal conditions which varied from year to year. For Merinos only, dry ewes grew about 4% more wool than lactating ewes. No other effects of reproduction on fleece weights were observed.


2017 ◽  
Vol 21 (2) ◽  
pp. 123-128 ◽  
Author(s):  
Nirmala Juita ◽  
. Iskandar ◽  
. Sudarsono

One of factors that is interasting from Vertisol to be investigated beside the management of the soil fertility was color variations which can vary from gray to brown and brownish red. Exclusive characteristics of Vertisol are shrink swell capacity with clay dominant clay that make agricultural activities in the Jeneponto area less productive. The purpose of this study was to assess the differences of physical and chemical characteristics of black and red Vertisol in Jeneponto R.egency. The research location was based on the difference and overlaying of soil color. Black soils were taken from the village Bontomarannu and Tonrokassi Timur while red soil and overlaying colors of red and black soil were taken from the village Sarroanging. Results showed that one of the chemical characteristic which was very differences between black and red soils were calcium carbonate and base saturation. Generally CaCO3 on black soil was higher (ranged of 13.20-36.73%) than  red soil (ranged of 2.21-13.86%). As for overlaying colors of red and black soil were ranged of 2.62-3.88%. The highest base saturation was found in the black soil that was> 100%, red soil between 40-89% and overlaying colors red and black soil between 80-83%.  While Fe, Mn and Al concentrations were highest with citrate dithionite bicarbonate extracts followed by oxalate and pyrophosphate extracts. Clay montmorillonite minerals were present in all profiles observed.


2021 ◽  
Vol 5 (2) ◽  
pp. 63
Author(s):  
Dwi Eva Nirmagustina

Brown rice has physical and sensory characteristics that are less favorable despite its high content of nutrition and phytochemical. The germination process is one way to improve and increase the acceptance of brown rice. The objective research was to determine germination time and varieties of brown rice on the physical and chemical characteristics of germinated brown rice. The research was conducted in RAL with 2 factors, germination time (24, 48, and 72 hours) and rice varieties (Mentik susu, Ciherang, and Pandan wangi). The data obtained were processed with analysis of variance to determine the effect of treatment on the parameters tested. If the effect is significant, then to determine the difference between treatments, a Tukey test is performed. Germination time of 24, 48, and 72 hours affected the color, germination, weight, dimensions of lenght, width, and thickness, bulk density, hydration capacity and swelling of germinated brown rice var. Mentik susu, Ciherang, and Pandan wangi. Germination time of 24, 48, 72 hours affected the chemical composition of BCG var. Mentik susu, Ciherang, and Pandan wangi. Based on observations of the physical and chemical characteristics of BCG var. Mentik susu, Ciherang, and Pandan wangi, germination time of 48 hours is recommended to do the germination with germination time of 48 hours compared to germination time of 24 and 72 hours.


Author(s):  
C. Goessens ◽  
D. Schryvers ◽  
J. Van Landuyt ◽  
A. Verbeeck ◽  
R. De Keyzer

Silver halide grains (AgX, X=Cl,Br,I) are commonly recognized as important entities in photographic applications. Depending on the preparation specifications one can grow cubic, octahedral, tabular a.o. morphologies, each with its own physical and chemical characteristics. In the present study crystallographic defects introduced by the mixing of 5-20% iodide in a growing AgBr tabular grain are investigated. X-ray diffractometry reveals the existence of a homogeneous Ag(Br1-xIx) region, expected to be formed around the AgBr kernel. In fig. 1 a two-beam BF image, taken at T≈100 K to diminish radiation damage, of a triangular tabular grain is presented, clearly showing defect contrast fringes along four of the six directions; the remaining two sides show similar contrast under relevant diffraction conditions. The width of the central defect free region corresponds with the pure AgBr kernel grown before the mixing with I. The thickness of a given grain lies between 0.15 and 0.3 μm: as indicated in fig. 2 triangular (resp. hexagonal) grains exhibit an uneven (resp. even) number of twin interfaces (i.e., between + and - twin variants) parallel with the (111) surfaces. The thickness of the grains and the existence of the twin variants was confirmed from CTEM images of perpendicular cuts.


Author(s):  
Galen Strawson

This chapter examines the difference between John Locke's definition of a person [P], considered as a kind of thing, and his definition of a subject of experience of a certain sophisticated sort [S]. It first discusses the equation [P] = [S], where [S] is assumed to be a continuing thing that is able to survive radical change of substantial realization, as well as Locke's position about consciousness in relation to [P]'s identity or existence over time as [S]. It argues that Locke is not guilty of circularity because he is not proposing consciousness as the determinant of [S]'s identity over time, but only of [S]'s moral and legal responsibility over time. Finally, it suggests that the terms “Person” and “Personal identity” pull apart, in Locke's scheme of things, but in a perfectly coherent way.


Food Industry ◽  
2018 ◽  
Vol 3 (4) ◽  
Author(s):  
Nataliia V. Nepovinnykh ◽  
Yuri A. Kodatsky ◽  
Oksana N. Klyukina ◽  
Nataliia M. Ptichkin ◽  
Samira Yeganehzad

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