کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
4725708 1639955 2015 24 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Legacy effects on sediments in river corridors
ترجمه فارسی عنوان
اثرات میراث بر رسوبات در رودخانه های رودخانه
کلمات کلیدی
رسوب میراث، سد، کشاورزی، چوب اکتشاف، خروس ها، آلاینده ها
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات زمین شناسی
چکیده انگلیسی

Legacy effects on river sediments are those which alter the location and volume of sediments and/or presence of contaminants within the sediments as a result of human activities. This review broadens the typical definition of legacy sediments and discusses human activities that create legacy effects on sediments in terms of three categories: activities that reduce sedimentation within river corridors — defined as channels, floodplains and riparian zones, and hyporheic zones; activities that enhance sedimentation in river corridors; and activities that contaminate river sediments with diverse pollutants. People reduce sedimentation within river corridors via three basic mechanisms: reducing sediment supply to the river corridor through changes in land cover or by trapping and storing sediment within the river corridor; increasing the ability of a river to transport sediments downstream by either increasing water supply to the channel or reducing physical channel complexities that promote flow separation, hydraulic resistance, and sedimentation; and disconnecting channels from floodplains, which are typically sediment storage zones and sediment sources for the channel. Conversely, enhanced sedimentation within river corridors results from increased sediment supply from uplands or upstream river segments and from decreased ability of a river to transport sediments downstream. Contamination of river sediments can result from nearly every conceivable human activity within a drainage basin (e.g., deforestation, agriculture, urbanization, industrial facilities, wastewater treatment). Contaminants can also enter a drainage basin from sources outside the basin boundaries because of contaminant transport within the tissues of migratory animals and via atmospheric deposition. Because many contaminants travel adsorbed to sediments, these pollutants can be concentrated within river corridors by activities that enhance sediment deposition. Legacy effects on sediments are now ubiquitous and abundant within river corridors around the world and can continue to alter river form and function long after cessation of the human activity that created the legacy. River management must be informed by accurate knowledge of the distribution and characteristic of legacy effects on sediments and geoscientists can contribute specialized knowledge to understanding and managing these sediments.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Earth-Science Reviews - Volume 147, August 2015, Pages 30–53
نویسندگان
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