Sensitivity of southern quebec lakes to acidic precipitation

Physico-chemical data from 258 Quebec lakes were collected during spring and summer 1980. These data are examined in order obtain a first general diagnosis of lake acidification in Quebec. The spatial variation of the mineralization of lakes is interpreted in relation to lithology and glacial deposits, allowing the identification of Shield areas particularly threatened by acid precipitation. A strong south-west to north-east gradient in sulphate concentration is observed and interpreted as a result of long range atmospheric transport of S and as an indication of increased sulphate levels in southern Quebec lakes. The frequency distribution of pH values and the relation between pH and sulphate are examined; the results obtained suggest that many Shield lakes are probably affected by acid precipitation. A comparison is made between spring and summer conditions; data obtained in spring show a substantial decrease in pH and alkalinity.     

First detection of Bursaphelenchus mucronatus (Nematoda: Aphelenchoididae) on Monochamus sutor (Coleoptera: Cerambycidae) in Romania

As a result of the detection of the pinewood nematode Bursaphelenchus xylophilus in Portugal, and its subsequent spread to Spain, intense surveys were conducted to screen for the presence of Bursaphelenchus species in Romania. Herein, we report recent surveys of insects potentially vectoring Bursaphelenchus species collected using trap trees or pheromone‐baited traps placed in the forest. Trap felled spruce trees (Picea abies) and pheromone‐baited traps were installed in six different counties in Romania (Bra?ov, Sibiu, Suceava, Hunedoara, Timi? and Dâmbovi?a). Ten different species of insects distributed among Curculionidae and Cerambycidae were obtained. Nematodes were extracted from insects and observed to validate the presence of Bursaphelenchus specimens. One female identified as Monochamus sutor was the only specimen carrying nematodes in the genus Bursaphelenchus. Nematodes were identified as B. mucronatus based on morphological and molecular features. This is the first detection and report of natural spread of B. mucronatus in Romania. The absence of B. xylophilus was confirmed in the areas of Romania surveyed in this work.     

Successful mechanical eradication of spotted bass (Micropterus punctulatus (Rafinesque, 1819)) from a South African river

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