نتایج جستجو برای: erosion and sedimentation

تعداد نتایج: 16833835  

Journal: :مدیریت خاک و تولید پایدار 0
مارال خدادادی دانشجوی دکتری/دانشگاه تهران منوچهر گرجی دانشیار/ دانشگاه تهران محمد قنادی مراغه پژوهشگاه علوم و فنون هسته ای، سازمان انرژی اتمی ایران علی سامانی بهرامی پژوهشگاه علوم و فنون هسته ای، سازمان انرژی اتمی ایران میر حسین میر سید حسینی دانشیار/ گروه مهندسی و علوم خاک، پردیس کشاورزی و منابع طبیعی، دانشگاه تهران قوام الدین زاهدی امیری دانشیار/ دانشکده جنگلداری و اقتصاد جنگل، پردیس کشاورزی و منابع طبیعی، دانشگاه تهران معین مفتاحی

over the past decades, the fallout radionuclides 137cs, 210pbex and 7be are increasingly being used to quantify soil erosion and sedimentation rates. although studies using 137cs and to some extent 210pbex are now well-documented, there is a need for further work aimed at exploring the use of 7be, particularly in arid and semi-arid areas. investigating soil erosion processes occurring over shor...

2006
Julien Charreau Stuart Gilder Yan Chen Stéphane Dominguez Jean-Philippe Avouac Sevket Sen Marc Jolivet Yongan Li Weiming Wang

We report a magnetostratigraphic and rock magnetic study of the Yaha section, located on the southern flank of the central Tian Shan mountains, Asia. Our results show a twofold increase in sedimentation rate as well as marked changes in rock magnetic characteristics ca. 11 Ma. After 11 Ma, sedimentation rate remained remarkably constant until at least 5.2 Ma. These findings are consistent with ...

2005
René H. Germain

Harvest access systems (forest roads, skid trails, and landings) account for 90% of the erosion and sedimentation during harvesting activities. A well-planned harvest access system can reduce the surface area disturbed by logging, thereby decreasing the potential for erosion and sedimentation. Most Best Management Practices (BMP) guidelines suggest that the area disturbed by the harvest access ...

Journal: :مرتع و آبخیزداری 0
علی اکبر نظری سامانی استادیار دانشکده منابع طبیعی، دانشگاه تهران حسام هروی کارشناس ارشد آبخیزداری، دانشکده منابع طبیعی، دانشگاه تهران مهدی پناهی استادیار گروه مهندسی آب، دانشگاه زنجان مسعود جعفری شلمزاری دانشجوی دکتری بیابان زدایی دانشگاه علوم کشاورزی و منابع طبیعی گرگان

natural landscape alternation is a problem that has been under debate for a long time. landutilization techniques like agriculture, forest and rangelands, residential and urban are amonginfluential criteria affecting erosion severity and sediment yield in a given region. in this respect,land management is a promising option to mitigate it. thus, acquaintance with quantitative soilerosion owing ...

2005
Benjamin Neidhold Markus Wacker Oliver Deussen

Realistically eroded terrain is a base of almost every outdoor visualization for simulators or computer games. In order to achieve convincing results physically based erosion algorithms are necessary. We present a new method that combines a non-expensive fluid simulation with an erosion algorithm. Both parts are running at interactive rates so the artist is able to influence the erosion process...

2011
G. D. Betrie Y. A. Mohamed A. van Griensven

Soil erosion/sedimentation is an immense problem that has threatened water resources development in the Nile river basin, particularly in the Eastern Nile (Ethiopia, Sudan and Egypt). An insight into soil erosion/sedimentation mechanisms and mitigation methods plays an imperative role for the sustainable water resources development in the region. This paper presents daily sediment yield simulat...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه تربیت مدرس - دانشکده علوم انسانی 1389

rivers and runoff have always been of interest to human beings. in order to make use of the proper water resources, human societies, industrial and agricultural centers, etc. have usually been established near rivers. as the time goes on, these societies developed, and therefore water resources were extracted more and more. consequently, conditions of water quality of the rivers experienced rap...

Journal: :تحقیقات جغرافیایی 0
موسی همتی مهدی احمدی مهدی احمدی شمس اله عسگری مرکز تحقیقات کشاورزی و منایع طبیعی استان ایلام

abstract ground water flow and skin is the most important phenomenon in the process streams are involved not only in the face of the whole earth, but also of the life of man on earth can. degradation of coastal erosion, lateral stability and continuity in iran and around the world each year destroys fertilized agricultural lands around the river, coastal installations, bridges, and is general h...

Journal: :iranian journal of earth science 0
kamal h karim department of geology, university of sulaimani, iraq zardasht a taha department of geology, university of sulaimani, iraq

new simplified tectonic models and depositional history of late cretaceous rocks are established in a part of zagros orogenic belt that is located in the northeastern iraq. these rocks constutes the most important cretaceous oil reservoir in the middle east. the dependent tools are petrography, field study and the concept of drowning phases. this concept is relatively new and accurate in explan...

2002
Grant A. Meyer Jennifer L. Pierce

Fire management addressing post-fire erosion and aquatic ecosystems tends to focus on shortterm effects persisting up to about a decade after fire. A longer perspective is important in understanding natural variability in post-fire erosion and sedimentation, the role of these processes in structuring habitat, and future expectations in light of a warming climate and environmental change. In coo...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید