نتایج جستجو برای: water and wind erosion

تعداد نتایج: 16955916  

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In the long-term, wind erosion has considerable impact on rangelands. The aim of this study is to understand the changes of Hanitiyeh Rangelands located 30 kilometers east of Ahvaz and its function. Two transects, 42 meters in length, in wind gradient, patch and inter patch with 5 repeats that included shrub log complex, bush, grass, shrub, shrub-grass and bare open soil were measured. In addit...

Journal: :Environmental Modelling and Software 2001
Hua Lu Yaping Shao

In this paper, we present an integrated wind-erosion modelling system which couples a physically based wind-erosion scheme, a high-resolution atmospheric model and a dust-transport model with a geographic information database. This system can be used to determine the pattern and intensity of wind erosion, in particular, dust emission from the surface and dust concentration in the atmosphere. Th...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه اراک - دانشکده علوم 1392

the history of plant’s used for mankind is as old as the start of humankind. initially, people used plants for their nutritional proposes but after the discovery of medicinal properties, this natural ?ora became a useful source of disease cure and health improvement across various human communities. berberis vulgaris is one of the medicinal plants used in iranian traditional medicine. berberis ...

Journal: :جغرافیا و مخاطرات محیطی 0
منیژه قهرودی تالی بهاره میرزاخانی آتنا عسگری

introduction desertification phenomena is a critical problem in dry climates. everglades, playas and shallow lakes are the main landscapes in the closed basins of iran, which are formed under tectonic and climatic influences during the pleistocene and holocene periods. duo to climate changes, lack of precipitation, human activity and mismanagement of water resources, entering water has been red...

2013
Weimin Gao Zhiren Wu Zhishen Wu

A novel hydrophilic polyurethane (abbreviated as W-OH) was developed and applied as a sustainable sand-fixing material. This paper on the chemical sand fixation mechanism of W-OH discusses the adhesive force between the W-OH solid and sand particles. The solidification mechanism was investigated and the solidifying time was tested. And then the thickness and porosity of the W-OH sand-fixing lay...

2017
Arash Karimpour Qin Chen Robert R. Twilley

Wetland dominated estuaries serve as one of the most productive natural ecosystems through their ecological, economic and cultural services, such as nursery grounds for fisheries, nutrient sequestration, and ecotourism. The ongoing deterioration of wetland ecosystems in many shallow estuaries raises concerns about the contributing erosive processes and their roles in restraining coastal restora...

Journal: :مرتع و آبخیزداری 0
طیبه مصباح زاده استادیار گروه احیای مناطق خشک و کوهستانی، دانشکدة منابع طبیعی، دانشگاه تهران حسن احمدی استاد دانشگاه آزاد اسلامی، واحد علوم تحقیقات، تهران غلامرضا زهتابیان استاد گروه احیای مناطق خشک و کوهستانی، دانشکدة منابع طبیعی، دانشگاه تهران فریدون سرمدیان استاد گروه مهندسی خاک، دانشکدة مهندسی خاک، دانشگاه تهران فیروزه مقیمی نژاد کارشناس ارشد مرتعداری، دانشکدة منابع طبیعی، دانشگاه تهران

desertification is specific phenomenon of arid, semi-arid, dry sub humid regions. this phenomenon has a high rate in developing countries such as iran. the main objective of this research was calibration of imdpa model in abuzeidabad (kashan) region with emphasis on land criteria. imdpa model, introduced by iranian researchers to assess desertification intensity in iran. before application, the...

2003
SIMON J. VAN DONK EDWARD L. SKIDMORE

The Wind Erosion Prediction System (WEPS) includes submodels to simulate soil erosion by wind, roughness degradation and residue decomposition. These WEPS submodels were tested using data measured on a 600 m by 415 m farmer’s field, planted with winter wheat, near Burlington, Colorado, USA. Big Spring Number Eight (BSNE) samplers were used to measure wind blown sediment flux and automated devic...

Journal: :Environment international 2003
R Lal

Soil erosion is the most widespread form of soil degradation. Land area globally affected by erosion is 1094 million ha (Mha) by water erosion, of which 751 Mha is severely affected, and 549 Mha by wind erosion, of which 296 Mha is severely affected. Whereas the effects of erosion on productivity and non-point source pollution are widely recognized, those on the C dynamics and attendant emissio...

ژورنال: علوم آب و خاک 2020

In semi-arid regions, soils are weakly aggregated and subjected to water erosion processes especially rill and interrill erosion. There is no information on the rate of these water erosion types in semi-arid soils located in the hillslopes. Therefore, this study was conducted to determine the soils susceptibility to these erosion types in semi-arid region. A laboratory experiment was done in ei...

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