کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
6309436 1645519 2014 6 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
A new mechanism of macrophyte mitigation: How submerged plants reduce malathion's acute toxicity to aquatic animals
ترجمه فارسی عنوان
یک مکانیسم جدید کاهش تدریجی ماکروفیت: چگونه گیاهان غرق شده سمیت حاد مالاتیون را به حیوانات آبزی کاهش می دهند
کلمات کلیدی
فیزیوتراپی، مقابله با حشره کش ها، پوشش گیاهی آب زیرزمینی، مکروفیدها، سم شناسی زیست محیطی،
موضوعات مرتبط
علوم زیستی و بیوفناوری علوم محیط زیست شیمی زیست محیطی
چکیده انگلیسی
A growing body of evidence suggests that aquatic plants can mitigate the toxicity of insecticides to sensitive aquatic animals. The current paradigm is that this ability is driven primarily by insecticide sorption to plant tissues, especially for hydrophobic compounds. However, recent work shows that submerged plants can strongly mitigate the toxicity of the relatively hydrophilic insecticide malathion, despite the fact that this compound exhibits a slow sorption rate to plants. To examine this disparity, we tested the hypothesis that the mitigating effect of submerged plants on malathion's toxicity is driven primarily by the increased water pH from plant photosynthesis causing the hydrolysis of malathion, rather than by sorption. To do this, we compared zooplankton (Daphnia magna) survival across five environmentally relevant malathion concentrations (0, 1, 4, 6, or 36 μg L−1) in test containers where we chemically manipulated water pH in the absence of plants or added the submerged plant (Elodea canadensis) but manipulated plant photosynthetic activity via shading or no shading. We discovered that malathion was equally lethal to Daphnia at all concentrations tested when photosynthetically inactive (i.e. shaded) plants were present (pH at time of dosing = 7.8) or when pH was chemically decreased (pH = 7.7). In contrast, when photosynthetically active (i.e. unshaded) plants were present (pH = 9.8) or when pH was chemically increased (pH = 9.5), the effects of 4 and 6 μg L−1 of malathion on Daphnia were mitigated strongly and to an equal degree. These results demonstrate that the mitigating effect of submerged plants on malathion's toxicity can be explained entirely by a mechanism of photosynthesizing plants causing an increase in water pH, resulting in rapid malathion hydrolysis. Our findings suggest that current ecotoxicological models and phytoremediation strategies may be overlooking a critical mechanism for mitigating pesticides.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Chemosphere - Volume 108, August 2014, Pages 405-410
نویسندگان
, ,