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ضرر سنگینی که “فرسایش خاک” تحمیل می‌کند

ضرر سنگینی که “فرسایش خاک” تحمیل می‌کند

ایسنا/خوزستان استاد گروه خاک‌شناسی دانشگاه شهید چمران اهواز با بیان اینکه خسارات ناشی از فرسایش خاک بسیار جدی و قابل توجه است، گفت: در این خصوص یک برآورد در کشور صورت گرفته که مشخص کرده تا حدود ۲ تا ۴ میلیارد تن خاک بر اثر فرسایش از دست خواهیم داد که ۵۴ میلیارد دلار زیان حاصل از

ضرر سنگینی که "فرسایش خاک" تحمیل می‌کند

ایسنا/خوزستان استاد گروه خاک‌شناسی دانشگاه شهید چمران اهواز با بیان اینکه خسارات ناشی از فرسایش خاک بسیار جدی و قابل توجه است، گفت: در این خصوص یک برآورد در کشور صورت گرفته که مشخص کرده تا حدود ۲ تا ۴ میلیارد تن خاک بر اثر فرسایش از دست خواهیم داد که ۵۴ میلیارد دلار زیان حاصل از این فرسایش صورت گرفته و بیش از درآمد نفتی کشور ما است.

احمد لندی در گفت‌وگو با ایسنا، اظهار کرد: پدیده فرسایش خاک باعث تخریب سنگ‌ها و تشکیل خاک می‌شود. این پدیده ممکن است بر اثر عوامل طبیعی نیز رخ دهد اما نگرانی بیشتر در خصوص فرسایشی است که به دلیل دخالت‌ها و ندانم‌کاری‌های بشر رخ می‌دهد؛ از جمله قطع درختان، چرای بی‌رویه دام‌ها، تبدیل زمین‌های شیب‌دار به اراضی کشاورزی، احداث جاده بدون توجه به نکات مهندسی و ایجاد تاسیسات یا عدم ایجاد موانعی که بتواند از فرسایش هنگام ایجاد تاسیسات جلوگیری کند.

وی با اشاره به انواع فرسایش خاک، تصریح کرد: ما دو نوع فرسایش داریم که شامل فرسایش آبی و فرسایش بادی است؛ فرسایش آبی به دلیل جریانات آب رخ می‌دهد و فرسایش بادی نیز باعث جابه‌جا شدن ذرات خاک از مکانی به مکان دیگر می‌شود که ما هر دو این پدیده را در استان خوزستان تجربه کرده‌ایم.

عوارض فرسایش بادی خاک در خوزستان

استاد گروه خاک شناسی دانشگاه شهید چمران اهواز با بیان اینکه آثار فرسایش بادی را در سال‌های اخیر به وضوح در استان خوزستان مشاهده کردیم، گفت: فرسایش بادی را در استان به وضوح مشاهده کردیم که باعث مختل شدن فعالیت‌ها. ایجاد بیماری‌های تنفسی، آلایندگی، ضربه زدن به تاسیسات، عدم فتوسنتز خوب گیاهان، کاهش کاشت محصولات و از بین رفتن برخی موجودات مانند زنبورها از عوارض فرسایش بادی بود.

خسارات ناشی از فرسایش خاک بسیار جدی است

لندی با بیان اینکه خسارات ناشی از فرسایش خاک بسیار جدی و قابل توجه است، تاکید کرد: حدود ۷۰۰ هزار هکتار زمین در استان خوزستان وجود دارد که در معرض فرسایش بادی قرار دارند که از این تعداد حدود ۲۰۰ هزار هکتار تپه‌های ماسه‌ای و شنی و مابقی کانون‌های گرد و غبار هستند.

اثرات منفی فرسایش آبی خاک

وی با اشاره به عوارض فرسایش خاک توسط آب، ادامه داد: فرسایش آبی نیز به هنگام بارش باران به راحتی در رودخانه کارون دیده می‌شود، به این ترتیب که آب رودخانه کاملا گل‌آلود و باعث ایجاد رسوب و جزیره‌هایی در بستر رودخانه می‌شود.

عضو هیات علمی گروه خاک شناسی دانشگاه شهید چمران اهواز ادامه داد: فرسایش خاک طبیعتا مضرات زیادی برای طبیعت و محیط زیست دارد. در فرسایش آبی با کاهش حاصلخیزی زمین، از بین رفتن خاک سطحی، تخریب برخی جاده‌ها‏ و… روبرو خواهیم بود و در درازمدت ممکن است باعث جابه‌جایی محل سکونت در منطقه‌ای شود.

زیان ۵۴ میلیارد دلاری بر اثر فرسایش خاک 

وی ادامه داد: در این خصوص یک برآورد در کشور صورت گرفته که مشخص کرده تا حدود ۲ تا ۴ میلیارد تن خاک بر اثر فرسایش از دست خواهیم داد که ۵۴ میلیارد دلار زیان حاصل از این فرسایش صورت گرفته و بیش از درآمد نفتی کشور ما است.

عدم توجه مسئولان باعث تشدید فرسایش خاک شده است

استاد گروه خاک شناسی دانشگاه شهید چمران اهواز با بیان اینکه رسوبات پشت سدها نیز باعث ایجاد مشکلاتی برای نگهداری آب در پشت سد می‌شود، گفت: با توجه به اینکه فرسایش خاک به مرور زمان اتفاق می‌افتد و اگر به جاده‌ها و روستاها لطمه وارد نکند، به وضوح قابل دیدن نیست؛ بنابراین کارگزاران توجه زیادی به این پدیده نمی‌کنند و در نتیجه این مساله باعث تشدید فرسایش خاک در سال‌های اخیر شده است.

اگر فرسایش خاک جدی گرفته نشود، به منابع خاک ضربه وارد می‌شود

وی با اشاره به راه‌کارهایی برای جلوگیری از از وقوع این پدیده، تصریح کرد: باید علل این پدیده شناسایی شود؛ به عنوان مثال از قطع درختان، چرای بی‌رویه دام در مراتع، کشت در زمین‌های شیب‌دار و … جلوگیری شود.

لندی در پایان با بیان اینکه اگر این مساله جدی گرفته نشود، ضربه‌ای به منابع خاک وارد می‌شود، گفت: با توجه به اینکه استان خوزستان منطقه خشک و نیمه خشک است، بنابراین باید به پوشش گیاهی اجازه بازسازی داد و اگر فرصت کافی داده نشود، خاک بر اثر جریانات باد و آب دچار فرسایش می‌شود.

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منبع:ایسنا

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