SEASONAL CHANGES IN BACKGROUND LEVELS OF MERCURY IN SURFACE HORIZONS OF FORESTED SOILS IN ALBERTA

1983 ◽  
Vol 63 (2) ◽  
pp. 397-400 ◽  
Author(s):  
M. J. DUDAS ◽  
K. CANNON

Content of mercury in organic soil horizons was monitored to ascertain seasonal changes in background levels. L, F, and H horizons were relatively enriched in mercury in early spring. Levels then diminished and reached seasonal low values in August. Content of mercury then increased twofold during September after which levels declined to summer values. F horizons had the highest content of mercury and H horizons had the lowest. Key words: Mercury cycling, mercury dynamics, heavy metal

Soil Science ◽  
1992 ◽  
Vol 154 (5) ◽  
pp. 420-425 ◽  
Author(s):  
M. M. HARRIS ◽  
L. O. SAFFORD

2018 ◽  
Vol 141 (2) ◽  
pp. 167-181 ◽  
Author(s):  
Christine Heuck ◽  
Georg Smolka ◽  
Emily D. Whalen ◽  
Serita Frey ◽  
Per Gundersen ◽  
...  

2020 ◽  
Vol 27 (2) ◽  
pp. 195-210
Author(s):  
Paweł Świsłowski ◽  
Jan Kříž ◽  
Małgorzata Rajfur

AbstractIn the year 2016, passive biomonitoring studies were conducted in the forest areas of southern and north-eastern Poland: the Karkonosze Mountains (Kark), the Beskidy Mountains (Beskid), Borecka Forest (P. Bor), Knyszynska Forest (P. Kny), and Białowieza Forest (P. Bia). This study used bark from the tree, Betula pendula Roth. Samples were collected in spring (Sp), summer (Su), and autumn (Au). Concentrations of Mn, Fe, Ni, Cu, Zn, Cd, and Pb were determined for the samples using the atomic absorption spectrometry method with flame excitation (F-AAS). Based on the obtained results, the studied areas were ranked according to level of heavy-metal deposition: forests of southern Poland > forests of north-eastern Poland. Some seasonal changes in the concentrations of metals accumulated in bark were also indicated, which is directly related to their changing concentrations in the air during the calendar year, for instance, the winter heating season produces higher concentrations of heavy metals in the bark samples taken in spring. When deciding to do biomonitoring studies using bark, but also other biological materials, it is necessary to take into account the period in which the conducted research is done and the time when the samples are taken for analysis, because this will have a significant impact on the obtained results.


2015 ◽  
Vol 18 (1) ◽  
Author(s):  
Endang Supriyantini ◽  
Hadi Endrawati

Logam berat Fe merupakan logam berat essensial yang keberadaannya dalam jumlah tertentu sangat dibutuhkan oleh organisme hidup, namun dalam jumlah yang berlebih dapat menimbulkan efek racun.Penelitian ini bertujuan untuk menganalisis kandungan dan tingkat pencemaran logam berat Fe pada air, sedimen, dan kerang hijau (Perna viridis) di perairan Tanjung Emas Semarang. Penelitian ini dilaksanakan pada tanggal 7 November dan 7 Desember 2013 dengan metode penelitian deskriptif. Logam berat Fe dalam sampel air, sedimen dan kerang hijau dianalisis di Laboratorium Balai Besar Teknologi Pencegahan Pencemaran Industri (BTPPI) Semarang dengan menggunakan metode AAS (AtomicAbsorption Spectrophotometry). Hasil penelitian menunjukkan bahwa perairan Tanjung Emas masih dalam taraf terkontaminasi logam Fe. Sedangkan pada sedimen dan pada kerang hijau (Perna viridis) sudah terindikasi tercemar logam Fe.Meskipun demikian variasi faktor lingkungan seperti suhu, salinitas, pH, kecepatan arus dan jenis sedimen juga memberikan kontribusi yang cukup penting terhadap kandungan logam Fe.Kata Kunci: logam Fe, Air, Sedimen, Perna viridis, metode AAS Heavy metalsiron(Fe) is anessentialheavy metalswhose presencein a certain amountis neededby living organisms, but inexcessiveamountscan causetoxic effects.The aims of the research is to analyze the heavy metals coccentration and the pollution level of Fe in water, sediment, and green mussels (Perna viridis) at Tanjung Emas Semarang. This research was conducted from 7 November and 7 December 2013 using the Atomic Absorption Spectrophotometry (AAS) and research methodswithdescriptive. The results showed that the waters of the Tanjung Emas is still in the stage of heavy metals contaminated iron (Fe). Sediment and green mussels (Perna viridis)already indicated heavy metal contaminatediron. However, variations inenvironmental factorssuch astemperature, salinity, pH, flow velocity an dsediment types also providean important contributionto heavy metal contentof iron(Fe).Key Words: Fe, water, sediment, Perna viridis, metode AAS


2005 ◽  
pp. 55-67 ◽  
Author(s):  
Ratko Kadovic ◽  
Olivera Kosanin ◽  
Snezana Belanovic ◽  
Milan Knezevic

During the last decades, forest ecosystems have been strongly exposed to the effect of different harmful pollutants, especially from the atmosphere. Harmful substances from the air, in addition to the direct effect on forest trees, also deposit in the soil, and have an adverse effect on soil chemistry and pedogenetic processes. The results of previous studies in Serbia (Kadovic, Knezevic, 2002, 2004) show some specificities regarding the accumulation and migration of heavy metals in the soil. The highest concentrations were found in the layers of forest litter and in the surface organo-mineral horizons. This paper presents the results of the study of heavy metal contents (Zn, Mn, Cu, Fe, Cd, Pb, Ni and Cr) in the organic horizon (forest litter) of beech forests in Serbia. The study of the heavy metal content in the organic horizon (forest litter) is very significant primarily in the aim of monitoring the trend of their migration through the soil profile and the effect on the soil properties and genesis. The soil quality in beech forests in Serbia was assessed within the Project ICP Forest, Level I, by the methodology UN/ECE-EC, 2000.


1979 ◽  
Vol 57 (10) ◽  
pp. 2022-2027 ◽  
Author(s):  
A. Garbutt ◽  
J. F. Leatherland ◽  
A. L. A. Middleton

Serum triiodothyronine (T3) and thyroxine (T4) concentrations were measured in a population of ruffed grouse, held outdoors under natural conditions of photoperiod and temperature. Blood samples were collected at monthly intervals, and at the solstices and equinoxes to test for variation through the light period. No changes in T4 or T3 levels were found during the light period but levels of T3 and T4 showed marked seasonal changes. Lowest T4 and T3 levels were found in birds during the winter months, with an increase in the concentration of both hormones in early spring concomitant with gonadal development in the adults. A lowering of serum T4 and T3 values was associated with the period of molt.


1986 ◽  
Vol 108 (3) ◽  
pp. 385-391 ◽  
Author(s):  
R. W. Lea ◽  
P. J. Sharp ◽  
H. Klandorf ◽  
S. Harvey ◽  
I. C. Dunn ◽  
...  

ABSTRACT Seasonal changes in concentrations of plasma LH, prolactin, thyroxine (T4), GH and corticosterone were measured in captive male ring doves exposed to natural lighting at latitude 56 °N. Plasma LH levels decreased steeply in autumn when the daylength fell below about 12·5 h but increased in November as the birds became short-day refractory. In comparison with plasma LH concentrations in a group of short-day refractory birds exposed to 6 h light/day from the winter solstice, plasma LH levels in birds exposed to natural lighting increased further in spring after the natural daylength reached about 12·5 h. There were no seasonal changes in plasma prolactin concentrations and plasma T4 concentrations were at their highest during December, January and February, the coldest months of the year. The seasonal fall in plasma LH levels in September was associated with a transitory increase in plasma T4, a transitory decrease in plasma corticosterone and a sustained increase in plasma GH. It is suggested that in the ring dove, short-day refractoriness develops rapidly in November to allow the bird to breed when the opportunity arises, during the winter and early spring. The annual breeding cycle is synchronized by a short-day induced regression of the reproductive system in the autumn, the primary function of which may be to enable the birds to meet the energy requirements for the annual moult. The changes in plasma T4, corticosterone and especially of GH at this time of year are probably concerned with the control of moult or the associated changes in energy requirements. J. Endocr. (1986) 108, 385–391


2014 ◽  
Vol 48 ◽  
pp. 168-175 ◽  
Author(s):  
Vladislav Chrastný ◽  
Aleš Vaněk ◽  
Eva Čadková ◽  
Alice Růžičková ◽  
Ivana Galušková ◽  
...  

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