Total mercury in terrestrial systems (air-soil-plant-water) at the mining region of San Joaquín, Queretaro, Mexico

Abstract Dragonflies (Order Odonata) are often considered to be biosentinels of environmental contamination. Dragonflies (n = 439) belonging to 15 species of eight genera were collected from an abandoned mercury (Hg) mining region in China to investigate the bioaccumulation of total Hg (THg) and methylmercury (MeHg). The THg and MeHg concentrations in dragonflies varied widely within ranges of 0.06–19 mg/kg and 0.02–5.7 mg/kg, respectively. THg and MeHg were positively correlated with bodyweight (THg: r2 = 0.10, P = 0.000; MeHg: r2 = 0.09, P = 0.000). Significant variations were observed among species, with the highest MeHg value (in Orthetrum triangulare) being 5-fold higher than the lowest (in Pantala flavescens). These variations were consistent with those of nitrogen isotope (δ15N) values. A health risk assessment found hazard quotients for specialist dragonfly-consuming birds of up to 7.2, which is 2.4 times greater than the permissible limit of 3, suggesting a potential health risk of exposure.

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Cheratte-Visé: a Muslim village in Wallonia

MIGRATION LETTERS ◽

10.33182/ml.v2i3.41 ◽

2005 ◽

Vol 2 (3) ◽

pp. 308-344

Author(s):

Christophe Parthoens ◽

Dina Sensi ◽

Altay Manco

Keyword(s):

Social Integration ◽

Host Country ◽

Local Authority ◽

Working Population ◽

Mining Region ◽

The Sixties ◽

Local Councillors ◽

Turkish Community

This article aims to describe the processes leading to social integration of a Turkish community at the beginning of the sixties who were resident in a mining region in Belgium. The stages through which this immigrant working population had to go through are described here: and how it managed, within a third of century, to become established in the district, to structure itself in associations, to be recognized by the local authority and the institutional fabric of the host country, and finally, to sit down at the same table with the local councillors.

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Detection of Plant Water Content with Needle-Type In-Situ Water Content Sensor

IEEJ Transactions on Sensors and Micromachines ◽

10.1541/ieejsmas.130.452 ◽

2010 ◽

Vol 130 (9) ◽

pp. 452-453

Author(s):

Hitoshi Katayanagi ◽

Norihisa Miki

Keyword(s):

Water Content ◽

Plant Water ◽

Needle Type

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The Method of Plant Water Status Measurement in Sweet Potato (Ipomoea Batatas (L) Lam.)

Beccariana Botanical Research Bulletin ◽

10.30862/bbrp.v7i1.274 ◽

2010 ◽

Vol 7 (1) ◽

Author(s):

Saraswati Prabawardani

Keyword(s):

Water Content ◽

Sweet Potato ◽

Relative Water Content ◽

Water Status ◽

Plant Water Status ◽

Equilibration Time ◽

Plant Water ◽

Font Size ◽

Potato Leaf ◽

Relative Water

The measurement of plant water status such as leaf water potential (LWP) and leaf relative water content (RWC) is important part of understanding plant physiology and biomass production. Preliminary study was made to determine the optimum amount of leaf abrasion and equilibration time of sweet potato leaf inside the thermocouple psychrometer chambers. Based on the trial, the standard equilibration time curve of a Peltier thermocouple for sweet potato leaf was between 2 and 3 hours. To increase the water vapour conductance across the leaf epidermis the waxy leaf cuticle should be removed or broken by abrasion. The result showed that 4 times leaf rubbings was accepted as the most effective way to increase leaf vapour conductance of sweet potato in the psychrometer chambers. In calculating the leaf relative water content, unstressed water of sweet potato leaves require 4 hours imbibition, whereas water stressed of sweet potato leaves require 5 to 6 hours to reach the saturation time. Either leaf water potential or relative water content can be used as a parameter for plant water status in sweet potato.

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