بررسی تأثیر گیاهان آبزی در کاهش فسفر و هدایت الکتریکی پساب شهری

نوع مقاله : مقاله پژوهشی

نویسندگان

1 کارشناس ارشد خاکشناسی، دانشگاه شاهرود

2 استادیار گروه آب و خاک، دانشکده کشاورزی، گروه پژوهشی زیست فناوری، دانشگاه شاهرود

چکیده

فسفر یک عنصر غذایی برای موجودات زنده محسوب می‌شود, اما مقادیر زیاد آن در آبهای زیرزمینی و سطحی سبب بروز مشکلات محیط زیستی نظیر پدیده پرغذایی می‌گردد. لذا باید قبل از تخلیه پساب به منابع آبی مقدار فسفر آن تا حد امکان کاهش یابد. از‌ روشهای مؤثر برای پالایش آبهای آلوده استفاده از گیاهان آبزی است. آزمایشی بر روی دو گیاه الودئا و عدسک ‌آبی با چهار تیمار در سه تکرار در پایلوت‌های آزمایشی با جریان بسته انجام ‌شد. تیمارها شامل: پساب اولیه همراه و بدون گیاه و پساب رقیق ‌شده (با درجه رقت‌2/1) همراه و بدون گیاه بود. مقدار pH ، EC و فسفر کل محلول در زمان ماندهای 8، 16 و 24 روز در نمونه‌های پساب ‌اندازه‌گیری ‌شد. نتایج نشان ‌داد که مقدار pH پساب در طول زمان تا 2/0 واحد کاهش یافت، اما بین تیمارها تفاوت معنی‌داری (05/0 p≤) در مقدارpH  مشاهده نشد. گیاهان، EC پساب را پس از 24 روز 7 درصد نسبت به شاهد کاهش دادند. غلظت فسفر کل محلول در تمام تیمارها با گذشت زمان روند کاهشی داشت و مقدار کاهش فسفر در تیمارهای عدسک ‌آبی و الودئا به‌ترتیب 49 و 7 درصد بود. به‌طور کلی عدسک آبی نسبت به الودئا توانایی بیشتری در کاهش فسفر پساب داشت.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Effect of Aquatic Plants on Phosphorus Removal and Electrical Conductivity Decrease in Municipal Effluent

نویسندگان [English]

  • Sara Samimi Loghmani 1
  • Ali Abbaspour 2
2 Shahrood university of technology
چکیده [English]

Phosphorus (P) is one of essential elements for living organisms, though its critical concentration in surface and ground waters impose a serious problem such as eutrophication. So treatment of polluted waters is required before discharging to water resources. One of effective ways to decrease water pollution is using aquatic plants. An experiment was conducted in pilots with a closed flowing system on two plants, elodea (egria densa) and duck weed (lemna minor) with four treatments and three replications. Data were analyzed in a factorial completely randomized design. Treatments included effluent with and without the plants, and effluent diluted (dilution grade 1/2) with and without the plants. Total dissolved P, electrical conductivity (EC) and pH value were measured after 8, 16 and 24 days in effluent samples. The results showed that pH value decreased up to 0.2 units during of 24 days of the experiment, but there was found no significant difference (p≤0.05) in pH values among the treatments. Both plants decreased EC about 7 % relative to the control (without plant) after 24 days. The plants were also effective in reducing total dissolved phosphorus, so that duck weed and elodea decreased total dissolved P in the effluent about 49 and 7%, respectively. It is concluded that duck weed is more effective in the P removal from the effluent than the other plant.

کلیدواژه‌ها [English]

  • Duck Weed
  • Elodea
  • Eutrophication
  • Effluent
  • Water Pollution
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