نتایج جستجو برای: sediment

تعداد نتایج: 36882  

2015
Renata Gruca-Rokosz Janusz A. Tomaszek

The estimated diffusion fluxes of methane (CH4) and carbon dioxide (CO2) at the sediment-water interface in the Rzeszów Reservoir in southeastern Poland are presented. The relevant studies were conducted during 2009, 2010, and 2011. Calculated fluxes ranged from 0.01 to 2.19 mmol m-2 day-1 and from 0.36 to 45.33 mmol m-2 day-1 for methane and carbon dioxide, respectively. While the values for c...

2015
Shimin Lu Xingguo Liu Zhuojun Ma Qigen Liu Zongfan Wu Xianlei Zeng Xu Shi Zhaojun Gu

Pond aquaculture is the major freshwater aquaculture method in China. Ammonia-oxidizing communities inhabiting pond sediments play an important role in controlling culture water quality. However, the distribution and activities of ammonia-oxidizing microbial communities along sediment profiles are poorly understood in this specific environment. Vertical variations in the abundance, transcriptio...

Journal: :Marine pollution bulletin 2017
Graham K P Muir Kieran M Tierney Gordon T Cook Gillian MacKinnon John A Howe Johanna J Heymans David J Hughes Sheng Xu

Ecosystem uptake and transfer processes of Sellafield-derived radiocarbon (14C) within the Irish Sea were examined. Highly variable activities in sediment, seawater and biota indicate complex 14C dispersal and uptake dynamics. All east basin biota exhibited 14C enrichments above ambient background while most west basin biota had 14C activities close to background, although four organisms includ...

Journal: :Environmental science and pollution research international 2016
Hossein Arfaeinia Iraj Nabipour Afshin Ostovar Zahra Asadgol Ehsan Abuee Mozhgan Keshtkar Sina Dobaradaran

Sediment samples from the coastal area of Asaluyeh harbor were collected during autumn and spring 2015. The acid-volatile sulfide (AVS) and simultaneously extracted metals (SEMs) were measured to assess the sediment quality and potential ecological risks. The average concentrations (and relative standard deviation (RSD)) of AVS in the industrial sediments were 12.32 μmol/g (36.91) and 6.34 μmol...

2013
Sun Jichao Wang Guangqian

Studies about sediment erosion were mainly concentrated on the river channel sediment, the terrestrial sediment, and the underground sediment. The transport process of underground sediment is studied in the paper. The concept of the flush potential sediment is founded. The transport equation with stable saturated seepage is set up, and the relations between the flush potential sediment and wate...

Abstract The forest road is most important sediment sours in the forest regions. the forest roads with remove vegetation cover and disorder hydraulic behavior regions, causes sediment product and problems due of sediment. This study has been done to surveying sediment factors roll in the sediment producing in the northern forest road. For this goal were selected purpose road sections by using h...

Journal: :Marine pollution bulletin 2006
Michael H Bothner Richard L Reynolds Michael A Casso Curt D Storlazzi Michael E Field

Sediment traps were used to evaluate the frequency, cause, and relative intensity of sediment mobility/resuspension along the fringing coral reef off southern Molokai (February 2000-May 2002). Two storms with high rainfall, floods, and exceptionally high waves resulted in sediment collection rates>1000 times higher than during non-storm periods, primarily because of sediment resuspension by wav...

The variable and complex nature of the sediment load of rivers has led that the estimation of sediment entering the reservoirs and the production of long term sediment, for determining the lifetime of the structures encounter with the problem. Application of sediment rating curves is one of the most common methods for estimating the suspended sediment load of rivers. Regardless of the accuracy ...

Journal: :Science 1954
B R Colby C H Hembree

A natural chute in the Niobrara River near Cody, Nebr., constricts the flow of the river except at high stages to a narrow channel in which the turbulence is sufficient to suspend nearly the total sediment discharge. Because much of the flow originates in the sandhills area of Nebraska, the water discharge and sediment discharge are relatively uniform. Sediment discharges based on depth-integra...

Journal: :Marine pollution bulletin 2014
P S Akhil C H Sujatha

This paper presents the first detailed investigation on the residual levels of organochlorine insecticide (OCI) concentrations in the Cochin estuarine sediment. It aims in elucidate their distribution and ecological impact on the aquatic system. Concentrations of persistent organochlorine compound (OC) were determined for 17 surface sediment samples which were collected from specific sites of C...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید