نتایج جستجو برای: sediment and soil erosion in watersheds although

تعداد نتایج: 21772706  

Journal: :مرتع و آبخیزداری 0
نسیم آرمان استادیار دانشکده منابع طبیعی، دانشگاه تهران علی سلاجقه استاد دانشکده منابع طبیعی، دانشگاه تهران سادات فیض نیا استاد دانشکده منابع طبیعی، دانشگاه تهران حسن احمدی استاد دانشکده منابع طبیعی، دانشگاه تهران جمال قدوسی استادیار گروه آبخیزداری، دانشگاه آزاد واحد علوم و تحقیقات تهران علی کیانی راد استادیار مؤسسه پژوهش های اقتصادی وزارت جهاد کشاورزی

identification of homogenous watershed sub basins allows generalization of environmental study results. for this purpose, first available data for 27 selected watersheds in north alborz regarding 21 variables including physiographic and climatic characteristics was gathered. the most important factors impacting upon soil erosion and sediment yield were equivalent rectangular length, mean annual...

Journal: :محیط زیست طبیعی 0
علی اکبرزاده دانش آموخته کارشناسی ارشد، پردیس کشاورزی و منابع طبیعی، دانشگاه تهران، ایران منوچهر گرجی استادیار پردیس کشاورزی و منابع طبیعی، دانشگاه تهران، ایران حسینقلی رفاهی استاد پردیس کشاورزی و منابع طبیعی، دانشگاه تهران، ایران حسن روحی پور دانشیار پژوهشی بخش بیابان موسسه تحقیقات جنگلها و مراتع کشور، ایران

today's, adverse effects of off-site erosion, namely damages received from sediment, is a serious bioenvironmental problem. one of the methods for temporary soil stabilization before permanent rehabilitation of vegetation cover, especially on slopes, for mitigating of bioenvironmental contaminants, is using materials having property to cementate the dispersed particles on the soil surface....

Journal: :مرتع و آبخیزداری 0
حمزه نور دانشجوی دکتری آبخیزداری، دانشگاه ترتیب مدرس، ایران سیدخلاق میرنیا دانشیار دانشگاه تربیت مدرس، ایران ملیحه سادات ظریف معظم کارشناس ارشد آبخیزداری، دانشگاه تربیت مدرس، ایران

some contaminants associate with soil particles and, thus, their transport and fate in the environment is determined by the soil erosion processes. eutrophication, low oxygen levels and high nutrient (nitrogen and phosphorus) concentrations in reservoirs, canals and other water courses, is a common water pollution feature. phosphorus (p) is one of the major plant nutrients and also the major nu...

2010
Leslie M. Reid Nicholas J. Dewey Thomas E. Lisle Susan Hilton

a r t i c l e i n f o The distribution and morphological characteristics of channels were mapped in a redwood forest at Caspar Creek, California, USA, to evaluate the extent to which recent logging has influenced channel conditions in the area. In the North Fork Caspar Creek watershed, second-cycle logging of the early 1990s appears to have triggered increased coalescence of discontinuous gulli...

2004
Elena Amore Carlo Modica Mark A. Nearing Vincenza C. Santoro

Accurate estimation of soil erosion due to water is very important in several environmental contexts, such as the assessment of potential soil loss from cultivated lands and the evaluation of the loss of water storage capacity in reservoirs due to sediment deposition. Several studies have been carried out to build models suitable to quantify the results of erosion processes. These models, calib...

2015
Preksedis Marco Ndomba

The main objective of this paper is to report on the preliminary validation results of the Global Assessment of Soil Degradation (GLASOD) as a tool for mapping sediment sources in Tanzania. This study was carried out in a well studied catchment, the Nyumba Ya Mungu (NYM) reservoir catchment located in the upstream of Pangani River Sub-basin. Previous studies in the same catchment used quantitat...

Journal: :تحقیقات جغرافیایی 0
علیرضا فرید حسینی دانشگاه فردوسی مشهد علیرضا زارعی شرکت مشاور طوس آب فرید فریدانی بردسکن دانشگاه فردوسی مشهد امین علیزاده دانشگاه فردوسی مشهد

soil erosion is the most important threat to the soil and water resources among the soil degradation processes in arid and semi-arid regions. this study was conducted in shirin-darreh basin, a semi-arid region in north-eastern iran, to evaluate the performance of erosion potential method (epm) and hydro-physical method (csy) in generating erosion potential and sediment load maps via geographic ...

2002
Yang Qinke Li Rui

Astract: This paper shows how recent situation of soil erosion evaluation and prediction on a regional scale based on the techniques of spatial information. The study, which was carried out in central China, identified sediment discharge, precipitation, soil composition, gully density and land use as erosion factors at the regional level. It showed that soil erosion can be assessed and predicte...

Extended abstract   1-Introduction Erosion is a geomorphologic and natural process that is always seen across the world, but this process is triggered by human activities, such as road construction, resulting in a significant negative impact on water resources, soil, environment and national economy. According to the above, preventing soil erosion is an important target in the management and...

2013
Adam J. Heathcote Christopher T. Filstrup John A. Downing

Agricultural soil loss and deposition in aquatic ecosystems is a problem that impairs water quality worldwide and is costly to agriculture and food supplies. In the US, for example, billions of dollars have subsidized soil and water conservation practices in agricultural landscapes over the past decades. We used paleolimnological methods to reconstruct trends in sedimentation related to human-i...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید