کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
4687496 1635593 2006 28 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Urban transformation of river landscapes in a global context
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات فرآیندهای سطح زمین
پیش نمایش صفحه اول مقاله
Urban transformation of river landscapes in a global context
چکیده انگلیسی

Over the past 50 years considerable progress has been made in understanding the impacts of urban development on river processes and forms. Such advances have occurred as urban population growth has accelerated around the world. Using a compilation of research results from more than 100 studies conducted in a range of areas (58 addressing morphological change), this paper describes how urbanization has transformed river landscapes across Earth’s surface, emphasizing the distribution of impacts in a global comparative context. Urban development induces an initial phase of sediment mobilization, characterized by increased sediment production (on the order of 2–10 times) and deposition within channels, followed by eventual decline that couples with erosion from increased runoff to enlarge channels. Data from humid and temperate environments around the world indicate that channels generally enlarge to 2–3 times and as much as 15 times the original size. Although research has emphasized temperate environments, recent studies of tropical areas indicate a tendency for channel reduction resulting from strong sediment erosion and deposition responses because of intense precipitation and highly weathered soils. Embryonic research in arid environments further suggests variable river responses to urbanization that are characterized by rapid morphological change over short distances. Regardless of location, the persistence of the sediment production phase varies from months to several years, whereas several decades are likely needed for enlarging channels to stabilize and potentially reach a new equilibrium. Urbanizing streams pose particular challenges for management given an inherent changing nature. Successful management requires a clear understanding of the temporal and spatial variations in adjustment processes.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Geomorphology - Volume 79, Issues 3–4, 30 September 2006, Pages 460–487
نویسندگان
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