Ashfaq Muhammad, Khan Muhammad Imran, Hanif Muhammad Asif
Department of Agri. Entomology, University of Agriculture, Faisalabad 38040, Pakistan.
Environ Entomol. 2009 Aug;38(4):1276-82. doi: 10.1603/022.038.0439.
This study focused on a 75-d microplot experiment to access lead (Pb) entrance into the terrestrial ecosystem using Morus alba (mulberry) and Bombyx mori (silkworm) as pollution indicator sources. The Pb(II) mobility in different systems was in the following order: synthetic effluents > soil > plant > larva > larva-fecal. The Pb(II) mobility from an inorganic source to different life forms was found to be highly dependent on soil pH and the concentration of Pb in synthetic effluents. At lower concentrations, Pb was less lethal to B. mori larvae. Fifth instars of B. mori were found to be more tolerant to toxicity caused by Pb compared with lower instars. M. alba was not a hyperaccumulator plant because Pb(II) concentration was <1,000 mg/kg at all soil pHs and Pb(II) concentrations in effluents. The maximum amount of Pb(II) detected in soil, mulberry leaves, silkworm larvae, and silkworm feces was 326.5 +/- 0.04, 42.78 +/- 0.02, 61.24 +/- 0.02, and 22.3 +/- 0.02 mg/kg, respectively.
本研究聚焦于一项为期75天的微区试验，以桑（桑树）和家蚕作为污染指示源，探究铅（Pb）进入陆地生态系统的情况。不同系统中Pb(II)的迁移性顺序如下：合成废水>土壤>植物>幼虫>幼虫粪便。发现从无机源到不同生命形式的Pb(II)迁移性高度依赖于土壤pH值和合成废水中Pb的浓度。在较低浓度下，Pb对家蚕幼虫的致死性较低。与低龄幼虫相比，发现家蚕五龄幼虫对Pb引起的毒性更具耐受性。桑树不是超富集植物，因为在所有土壤pH值和废水中Pb(II)浓度下，Pb(II)浓度均<1000 mg/kg。在土壤、桑叶、蚕幼虫和蚕粪便中检测到的Pb(II)最大量分别为326.5±0.04、42.78±0.02、61.24±0.02和22.3±0.02 mg/kg。
