We assessed the eVect of whole-stream nitrate enrichment on decomposition of three substrates diVering in nutrient quality (alder and oak leaves and balsa veneers) and associated fungi and invertebrates. During the 3-month nitrate enrichment of a headwater stream in central Portugal, litter was incubated in the reference site (mean NO3-N 82 g l ¡1) and four enriched sites along the nitrate grad...

Observation of nighttime nitrate radical (NO3) was performed by using long path differential optical absorption spectroscopy (LP-DOAS), on the outskirts of Hefei, China. The time series of NO3 and supporting parameters were simultaneously measured for a week (31 May-7 June 2006). The results indicated that the average concentration of NO3 was 15.6 pptv with an average lifetimes of 96 s, whereas...

[1] Longitudinal and diel measurements of dual isotope composition (dN and dO) in nitrate (NO3-N) were made in the Ichetucknee River, a large ( 8 m s ), entirely spring-fed river in North Florida, to determine whether isotopic variation can deconvolve assimilatory and dissimilatory removal. Comparing nitrate concentrations and isotope composition during the day and night we predicted (1) daytim...

Several collocated semicontinuous instruments measuring particulate matter with particle sizes < or =2.5 microm (PM2.5) sulfate (SO4(2-)) and nitrate (NO3-) were intercompared during two intensive field campaigns as part of the PM2.5 Technology Assessment and Characterization Study. The summer 2001 urban campaign in Queens, NY, and the summer 2002 rural campaign in upstate New York (Whiteface M...

Nitrate (NO3-) pollution in aquatic system is a worldwide problem. The temporal distribution pattern and sources of nitrate are of great concern for water quality. The nitrogen (N) cycling processes in a subtropical watershed located in Changxing County, Zhejiang Province, China were greatly influenced by the temporal variations of precipitation and temperature during the study period (Septembe...

A high concentration of nitrate (NO3) in surface water threatens aquatic systems and human health. Revealing nitrate characteristics and identifying its sources are fundamental to making effective water management strategies. However, nitrate sources in multi-tributaries and mix land use watersheds remain unclear. In this study, based on 20 surface water sampling sites for more than two years’ ...

In the framework of understanding the transport mechanism that governs the filtration of NO3- solution through a γ-Al2O3 membrane with a nominal pore size of 5 nm at low ultrafiltration, a series of various types of nitrate solutions and operating conditions were investigated. The effect of filtration parameters such as pH, applied pressure and NO3- concentration on the selectivity and permeabi...

Agricultural-induced increase of nitrate (NO3) loading in groundwater is a worldwide problem. This study investigates the impacts of agricultural activities on groundwater NO3 pollution in a Yellow River irrigated region. The agricultural land use patterns are dependent on the land and water conditions. Besides wheat–maize rotation, the most popular cultivation pattern, other patterns with high...

Under low growth-irradiance and/or excessive nitrogen (N) fertilization, the roots of leafy vegetables could take up nitrate (NO3) faster than the plant can convert it to organic nitrogen compounds. NO3 is suspected to have carcinogenic effect in human when eaten in high quantity. In this study, lettuce plants were first grown in an aeroponics system with full nutrients (full NO3) under full su...

Mercury (Hg) is one of the most dangerous pollutant heavy metals to environment, which causes several toxic effects in plants upon accumulation, such as induction oxidative stress. Nitrate (NO3) prevalent form incorporate nitrogen (N) higher plants, through its reduction nitrite (NO2) by enzyme nitrate reductase (NR). We studied physiological alterations caused Hg (0, 6 and 30 µM) alfalfa grown...