کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
4525406 1625623 2016 12 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Effects of macro-pores on water flow in coastal subsurface drainage systems
ترجمه فارسی عنوان
اثرات منافذ کلان بر جریان آب در سیستم های زهکشی زیرزمینی ساحلی
کلمات کلیدی
منافذ عمیق، اشباع نمک، جریان ترجیحی زه کشی، ناهمگنی خاک
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات فرآیندهای سطح زمین
چکیده انگلیسی


• Macro-pores significantly reduce the leaching efficiency.
• The time and amount of water required for leaching increase remarkably under the influence of macro-pores.
• Leaching efficiency is affected by the distribution of macro-pores.

Leaching through subsurface drainage systems has been widely adopted to ameliorate saline soils. The application of this method to remove salt from reclaimed lands in the coastal zone, however, may be impacted by macro-pores such as crab burrows, which are commonly distributed in the soils. We developed a three-dimensional model to investigate water flow in subsurface drainage systems affected by macro-pores distributed deterministically and randomly through Monte Carlo simulations. The results showed that, for subsurface drainage systems under the condition of continuous surface ponding, macro-pores increased the hydraulic head in the deep soil, which in turn reduced the hydraulic gradient between the surface and deep soil. As a consequence, water infiltration across the soil surface was inhibited. Since salt transport in the soil is dominated by advection, the flow simulation results indicated that macro-pores decreased the efficiency of salt leaching by one order of magnitude, in terms of both the elapsed time and the amount of water required to remove salt over the designed soil leaching depth (0.6 m). The reduction of the leaching efficiency was even greater in drainage systems with a layered soil stratigraphy. Sensitivity analyses demonstrated that with an increased penetration depth or density of macro-pores, the leaching efficiency decreased further. The revealed impact of macro-pores on water flow represents a significant shortcoming of the salt leaching technique when applied to coastal saline soils. Future designs of soil amelioration schemes in the coastal zone should consider and aim to minimize the bypassing effect caused by macro-pores.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Advances in Water Resources - Volume 87, January 2016, Pages 56–67
نویسندگان
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