نتایج جستجو برای: surface sediments

تعداد نتایج: 658804  

ژورنال: فیزیک زمین و فضا 2020

In the old Lut playa underneath the hills of nebkhas, the deepening of the waterways and the extent of the expansion of the cones and the nebkha morphometry are evidences of environmental changes. To study the above-mentioned factors, it is necessary to rebuild the morphodynamic conditions of the region. In this research, the changes in environmental conditions of the area are investigated and ...

2008
D. Alexakis

Geochemistry of surface hyporheic stream sediments, multivariate statistics and GIS database proved successful tools for assessing toxic element contamination in East Attica region. The objectives of this study were to assess the degree of contamination and to describe the surface hyporheic stream sediment geochemical variations in relation to geology, lithology and anthropogenic activities of ...

2000
J. P. Sweerts John W. M. Rudd C. A. Kelly

Parts of the sandy littoral sediment of a Precambrian shield lake (Lake 302s) were intermittently covered with a layer of flocculent organic-rich material l-20 mm thick. Sandy sediments with flocculent surface sediment had higher rates of respiration (31-105%) and photosynthesis (37224%) than those without. Densities of invertebrate macrofauna were 10 times higher in the flocculent surface sedi...

Homira Agah, Neda Sheijooni Fumani, Shirin Rahmanpour,

Total organic carbon has a major influence on both the chemical and biological processesthat take place in sediments. Algal bloom is one of the organic carbon levels in aquatic ecosystems. In 2009 algal bloom occurred in the Hormozgan province and prolonged for months, which finally setteled down in 2010. In this study the variations of total organic carbon (TOC), organic matter (TOM) and tot...

2009
Juan L. Bouzat

Bacteria exhibit the ability to metabolize a wide array of contaminants and, as a result, reduce their toxicity to wildlife and humans. The general goal of this project was to design and evaluate, as a proof-of concept, a DNA microarray assay to evaluate bacterial detoxification mechanisms in contaminated sediments. The assay consists of 100 probes that measure activity of bacterial remediation...

2007
T. S. Yun J. C. Santamarina C. Ruppel

[1] The mechanical behavior of hydrate-bearing sediments subjected to large strains has relevance for the stability of the seafloor and submarine slopes, drilling and coring operations, and the analysis of certain small-strain properties of these sediments (for example, seismic velocities). This study reports on the results of comprehensive axial compression triaxial tests conducted at up to 1 ...

Journal: :مرتع و آبخیزداری 0
محسن پادیاب دانشجوی دکتری آبخیزداری دانشکدة منابع طبیعی، دانشگاه تهران سادات فیض نیا استاد دانشکده منابع طبیعی دانشگاه تهران حسن احمدی استاد گروه آبخیزداری، دانشگاه آزاد اسلامی واحد علوم و تحقیقات تهران اردشیر شفیعی عضو هیئت علمی مرکز تحقیقات کشاورزی و منابع طبیعی استان کهکیلویه و بویراحمد

small precipitation with temporal and spatial variation of rainfall is the main responsible factors on flood occurrence in arid and semi arid regions. floods in their regions usually contain high concentration of sediments which when they are deposited on the surface of lands, they change the properties of soils of the area. in this research, the effect of floodwater spreading on physic-chemica...

Journal: :Journal of environmental quality 2005
W James Catallo T Junk

Benzothiazole (BT) is a natural and synthetic compound occurring in aquatic sediments and wastewater. The purpose of this work was to investigate BT biogeochemistry in controlled Eh/pH microcosms (CEPMs) containing estuarine sediments of different particle sizes (coarse, intermediate, fine) under oxidized and reduced conditions vs. killed controls, and tide simulation mesocosms (TSMs) containin...

2016
Long Ma Jinglu Wu Jilili Abuduwaili

Particle size analysis of lacustrine core sediments and atmospheric natural dust were conducted in the drainage area of Ebinur Lake in arid northwest China. Using a combination of (137)Cs and (210)Pb dating, a continuous record of aeolian transportation to the lake sediments and related factors over about the past 150 years was analyzed. Factor analysis revealed the particle-size distributions ...

2014
Mohsen Shahriari Moghadam Gholamhossein Ebrahimipour Behrooz Abtahi Alireza Ghassempour Mehri Seyed Hashtroudi

Polycyclic aromatic hydrocarbons (PAHs) biodegradation in contaminated sediment is an attractive remediation technique and its success depends on the optimal condition for the PAH-degrading isolates. The aims of the current study was to isolate and identify PAHs-degrading bacteria from surface sediments of Nayband Bay and to evaluate the efficiency of statistically based experimental design for...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید