The relationship between the vertical distribution and seasonal variation of limnetic species of Daphnia

1964 ◽  
Vol 15 (2) ◽  
pp. 684-690
Author(s):  
John Langdon Brooks
Keyword(s):  
Seasonal Variation ◽  
Vertical Distribution ◽  
The Relationship ◽  
The Vertical Distribution

scholarly journals Distribusi Vertikal Logam Pb, Zn, Cr dan Keterkaitannya Terhadap Karbon Organik Sedimen di Pantai Marunda, Jakarta

2020 ◽  
Vol 9 (2) ◽  
pp. 125-132
Author(s):  
Triyanti Nurhidayah ◽  
Lilik Maslukah ◽  
Sri Yulina Wulandari ◽  
Kurnia Kurnia
Keyword(s):  
Heavy Metals ◽  
Vertical Distribution ◽  
Lower Layer ◽  
Middle Layer ◽  
Average Concentration ◽  
Anthropogenic Activity ◽  
Sediment Texture ◽  
The Relationship ◽  
The Vertical Distribution ◽  
Very High

Pantai Marunda terletak di Teluk Jakarta dan berdekatan dengan muara Sungai Tiram. Kegiatan antropogenik di sekitar Pantai Marunda sangat tinggi, sehingga dapat menyumbang limbah yang mengandung logam berat Pb, Zn dan Cr. Limbah logam berat yang terakumulasi dalam perairan, akan  mengendap dalam sedimen dan seiring berjalannya waktu akan mengalami peningkatan. Tujuan dari penelitian ini, untuk mengetahui konsentrasi Pb, Zn, dan Cr berdasarkan kedalaman vertikal, hubungannya dengan karbon organik total (KOT) dan ukuran butir sedimen di Pantai Marunda. Sampel sedimen diambil menggunakan polietylen sediment core dan dipisahkan berdasarkan kedalamannya (1-3 cm, 4-6 cm, dan 7-9 cm). Logam berat dalam sedimen dianalisis menggunakan metode destruksi asam dan diukur nilai absorbansinya menggunakan AAS, karbon organik total menggunakan metode loss of ignition (LOI) dan analisa tekstur sedimen dengan metode pengayakan dilanjutkan pemipetan. Hasil menunjukkan bahwa konsentrasi rerata logam berat Pb, Zn, Cr secara berurutan pada lapisan atas sebesar 5,14; 107,19; dan 12,79 ppm, lapisan tengah sebesar 4,41; 100,20; 12,28  ppm serta lapisan bawah sebesar 4,8; 101,30; 14,10 ppm. Logam berat Zn dan Cr berkorelasi positif kuat terhadap KOT dan persentase lumpur, sedangkan terhadap Pb berkorelasi negatif. Hasil penelitian ini menggambarkan bahwa distribusi logam berat Pb, Zn dan Cr secara vertikal menunjukkan konsentrasi tinggi pada lapisan permukaan yaitu pada kedalaman sedimen 1-3 cm dan keberadaanya ditentukan oleh konsesntrasi  KOT dan fraksi sedimen jenis lumpur. The Marunda Beach is located on the Jakarta Bay and adjacent to the mouth of the Tiram River. Anthropogenic activity around Marunda Beach is very high, so it can contribute the heavy metals such as Pb, Zn and Cr. The heavy metal will accumulate in the sediment and over time will be increase. The purpose of this study was to determine the vertical distribution of Pb, Zn, Cr, and their relationship to total organic carbon (TOC) and the grain size. Sediment samples were taken using polyethylene cores and this sample separated based on their depth (1-3 cm, 4-6 cm, and 7-9 cm). The heavy metals were analyzed using acid destruction and absorbance values were measured using AAS, TOC using the loss of ignition (LOI) and sediment texture with a sifting method, followed by pipetting. The results showed that the average concentration of Pb, Zn, Cr in the upper layer was 5.14; 107.19; 12.79 ppm, in the middle layer of 4.41; 100.20; 12.28 ppm and in the lower layer 4.8; 101.30; 14.10 ppm, respectively. Zn and Cr are strongly positively correlated to TOC and mud, and vice versa, the relationship to Pb is negative. The results of this study found that the vertical distribution of Pb, Zn and Cr was high in the surface layer (1-3 cm) and their presence was determined by TOC concentration and mud fraction.

Daily inundation induced seasonal variation in the vertical distribution of soil water salinity in an estuarine mangrove forest under a tropical monsoon climate

2020 ◽  
Vol 35 (4) ◽  
pp. 638-649
Author(s):  
Akira Komiyama ◽  
Sasitorn Poungparn ◽  
Suthathip Umnouysin ◽  
Chadtip Rodtassana ◽  
Shogo Kato ◽  
...  
Keyword(s):  
Seasonal Variation ◽  
Vertical Distribution ◽  
Soil Water ◽  
Mangrove Forest ◽  
Water Salinity ◽  
Monsoon Climate ◽  
Tropical Monsoon ◽  
The Vertical Distribution

scholarly journals Seasonal variation in the vertical distribution of zone over Oakshin Gangotri, Antarctica

MAUSAM ◽  
2021 ◽  
Vol 42 (3) ◽  
pp. 275-278
Author(s):  
A.L. KOPPAR ◽  
S.C. NAGRATH
Keyword(s):  
Seasonal Variation ◽  
Vertical Distribution ◽  
Early Spring ◽  
The Other ◽  
Late Winter ◽  
Double Peak ◽  
The Vertical Distribution

Ozone soundings made from Dakshin Gangotri, Antarctica during 1987 are presented. The vertical distribution of ozone over Antarctica is characterised by a double peak profile, one around 200-150 hPa and the other around 50 hPa. During late winter-early spring the upper peak is considerably depleted. Tropospheric ozoe remains low and nearly constant throughout the year.  

Vertical distribution of forms of potassium in major soil series of Tamil Nadu

2003 ◽  
Vol 51 (3) ◽  
pp. 339-346 ◽  
Author(s):  
S. Natarajan ◽  
A. Renukadevi
Keyword(s):  
Organic Carbon ◽  
Vertical Distribution ◽  
Tamil Nadu ◽  
Water Soluble ◽  
The Other ◽  
Soil Series ◽  
Exchangeable K ◽  
The Relationship ◽  
The Vertical Distribution ◽  
Total Potassium

Fifteen major soil series at the rate of three for each soil group, namely red non-calcareous, red calcareous, black calcareous, brown calcareous and alluvial soils, were studied for the vertical distribution of different forms of potassium. The total potassium content varied from 515-5513 ppm and generally increased with depth. It was positively related with clay, silt, CaCO3, CEC and total Ca. Non-exchangeable K ranged from 340-1326 ppm and did not exhibit any uniformity in its distribution in soil profiles. The exchangeable K varied from 45-684 ppm and was positively related to organic carbon. NH4OAc-K ranged from 15-298 ppm. Soil properties like clay, silt, CaCO3 and organic matter were positively related to available K. Water-soluble K varied from 2-33 ppm and was found to decrease with the depth of the soil profile. It was positively correlated with organic carbon and negatively related to clay plus silt. Studies on the relationship between the above forms of potassium indicate that, except for total K, the other forms were closely related, indicating the possibility of predicting one from the other.

Vertical distribution, seasonality and troposphericity of ice-supersaturated air masses in the northern mid-latitudes from regular in-situ observations by passenger aircraft

2020 ◽  
Author(s):  
Andreas Petzold ◽  
Susanne Rohs ◽  
Mihal Rütimann ◽  
Patrick Neis ◽  
Berkes Florian ◽  
...  
Keyword(s):  
Seasonal Variation ◽  
Vertical Distribution ◽  
North Atlantic ◽  
Observation Data ◽  
European Research ◽  
Air Masses ◽  
The North ◽  
The North Atlantic ◽  
Passenger Aircraft ◽  
The Vertical Distribution

<p>The vertical distribution and seasonal variation of water vapour volume mixing ratio (H<sub>2</sub>O VMR), relative humidity with respect to ice (RH<sub>ice</sub>) and particularly of regions with ice-supersaturated air masses (ISSR) in the extratropical upper troposphere and lowermost stratosphere are investigated at northern mid-latitudes over the regions Eastern North America, the North Atlantic and Europe for the period 1995 to 2010.</p><p>Observation data originate from regular and continuous long-term measurements of H<sub>2</sub>O VMR, temperature and RH<sub>ice</sub> by instrumented passenger aircraft in the framework of the European research program MOZAIC which is continued as European research infrastructure IAGOS (from 2011; see www.iagos.org). The observation data are analysed with respect to the thermal and dynamical tropopauses, as provided by ERA-Interim. Additionally, collocated O<sub>3</sub> observations from MOZAIC are used as tracer for stratospheric air masses.</p><p>Our key results provide in-depth insight into seasonal and regional variability and tropospheric nature of ice-supersaturated air masses at various distances from the tropopause layer. For the vertical distribution and seasonal variation of ISSR occurrence we show a comparison of our results to radio soundings and to satellite observations of cirrus cloud occurrence from AIRS and TOVs Path B instruments. Finally, for all three regions, we investigate the trends and the dependencies of ISSR occurrence on the North Atlantic Oscillation (NAO) index.</p>

scholarly journals Seasonal variation of the crustacean fauna in the belowground and aboveground strata in a Halodule wrightii meadow of northeastern Brazil

2017 ◽  
Vol 107 (0) ◽  
Author(s):  
Kcrishna V. S. Barros ◽  
Jesser F. Souza-Filho ◽  
Ricardo J. C. Paiva ◽  
Catarina L. Araújo-Silva ◽  
Alexandre O. Almeida ◽  
...  
Keyword(s):  
Spatial Distribution ◽  
Seasonal Variation ◽  
Vertical Distribution ◽  
The Other ◽  
Northeastern Brazil ◽  
Halodule Wrightii ◽  
The Vertical Distribution

ABSTRACT The different microhabitats provided by seagrasses and the habit of the species determinate the vertical distribution of crustaceans. This study verified the influence of the seasonality on the spatial distribution of the crustacean community associated with a Halodule wrightii meadow. From April 2006 to July 2007, we performed fifteen samplings in Goiabeiras Beach, Ceará State, each with five sectioned replicates in belowground and aboveground. Cumaceans and the amphipod Hyale media (Dana, 1853) had a higher frequency, density, and dominance than the other taxa, in both strata. The community exhibited gradual changes along the study, in both the belowground and aboveground strata, but the seagrass structure was not sufficient to explain the vertical distribution of the crustacean fauna along the time.

Travelling disturbances in the ionosphere

1950 ◽  
Vol 202 (1069) ◽  
pp. 208-223 ◽  
Keyword(s):  
Seasonal Variation ◽  
Vertical Distribution ◽  
Sudden Change ◽  
Frequent Occurrence ◽  
Vertical Movements ◽  
Short Period ◽  
The Mean ◽  
The Vertical Distribution

Methods have been developed for the examination of the horizontal and vertical movements of short-period disturbances in the ionosphere. It has been found that quasi-periodic travelling disturbances with periods of from 10 to 60 min. are of frequent occurrence in the F region by day. They appear as temporary variations in the vertical distribution of ionization which show a horizontal progression and a vertical progression downwards. The horizontal directions of travel have a well-defined mean direction on most days. The mean direction shows a marked seasonal variation with a sudden change at each equinox. The horizontal rate of travel is usually between 5 and 10 km./min., and the rate of vertical progression downwards is approximately half the horizontal rate. The disturbances are considered to be variations of a compressional type in the atmosphere resulting in changes in the distribution of ionization.

scholarly journals Distribusi Vertikal Asplenium nidus L. di Kawasan Hutan Imbowiari, Kepulauan Yapen, Papua (Vertical Distribution of Asplenium nidus L. in the Imbowiari Forest, Yapen Islands, Papua)

2020 ◽  
Vol 8 (3) ◽  
pp. 390
Author(s):  
Edoward Krisson Raunsay ◽  
Maik Akobiarek ◽  
Marthinus Yohanis Ruamba
Keyword(s):  
Vertical Distribution ◽  
Host Tree ◽  
Bird Nest ◽  
Host Trees ◽  
Asplenium Nidus ◽  
The Relationship ◽  
The Vertical Distribution

Asplenium nidus L. has an important role as one of the bio-indicators of the cenderawasih bird nest and is massively found in the Imbowiari Forest, Yapen Islands Regency, Papua. Until now, there is no study on the investigation of their vertical distribution. This study aimed to identify the vertical distribution of A. nidus and the relationship with the height of the host trees. The population and samples of this study were all A. nidus existing in the Imbowiari Forest, and the samples were all A. nidus that is in the observation plot. This study employed a track path method consisting of 3 transects containing 15 observation plots. The results revealed 63 A. nidus in the area of Imbowiari Forest with the total number of host trees of 49. The A. nidus and host tree relationship was shown by the equation Y = 0,014X + 1.016 with R2 = 0,058. There was no correlation between the height of host trees and the vertical distribution of A. nidus. Keywords:  Asplenium nidus, Imbowiari Forest, vertical distribution

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