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Effects of nitrate concentration in interstitial water on the bioremediation of simulated oil-polluted shorelines

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Journal of Environmental Sciences 2007年第12期19卷 1491-1495页

作者： XIA Wen-xiang LI Jin-cheng SONG Zhi-wen SUN Ying-jie Department of environmental engineering Qingdao Technological University Qingdao 266033 China.

Nutrient addition has been proved to be an effective strategy to enhance oil biodegradation in marine shorelines. To determine the optimal range of nutrient concentrations in the bioremediation of oil-polluted beaches, nitrate was added to the simulated shoreline models in the initial concentration of 1, 5 and 10 mg/L. Whenever the NO3-N concentration declined to 70% of its original value, additional nutrients were supplemented to maintain a certain range. Results showed adding nutrients increased the oil biodegradation level, the counts of petroleum degrading bacteria （PDB） and heterotrophic bacteria （HB）, and the promoted efficiency varied depending on the concentration of nitrate. Oil degradation level in 5 mg/L （NO3-N） group reached as much as 84.3% accompanied with the consistently highest counts of PDB; while in l mg/L group oil removal efficiency was only 35.2%, and the numbers of PDB and HB were relatively low compared to the other groups supplemented with nutrients. Although counts of HB in the 10 mg/L group were remarkable, lower counts of PDB resulted in poorer oil removal efficiency （70.5%） compared to 5 mg/L group. Furthermore, it would need more NO3-N （0.371 mg） to degrade 1 mg diesel oil in the 10 mg/L group than in the 5 mg/L group （0.197 mg）. In conclusion, Nitrate concentration in 5 mg/L is superior to l and 10 mg/L in the enhancement of diesel oil biodegradation in simulated shorelines.

关键词： diesel oil 0# bioremediation nutrient concentration interstitial water

Nutrient profiles in interstitial water and flux in water-sediment interface of the Zhujiang Estuary of China in summer

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Acta Oceanologica Sinica 2001年第4期20卷 523-533页

作者：潘建明周怀阳刘小涯扈传昱董礼先张美 Key Lab of Ocean Dynamic Processes and Satellite Oceanography Second Institute of Oceanography State Oceanic Administration Hangzhou 310012 China Center of Coastal and Atmosphere Research HKUST Hong Kong Clear Water Bay Hong Kong

The profiles of nutrient salts in the interstitial water of sediment were analyzed in the Zhu- jiang Estuary in the summer of 1999, and based on the profiles of content and characteristic of nutri- ents, the relationship between nutrients in the interstitial water and organic matter decomposition in sediment was discussed. The results showed that ammonium with high content was the main existence form of nutrients in the interstital water of sediment, and the organic matter decomposition was com- pleted in anaerobic condition. The increase of ammonium content in the bottom water resulted from the decomposition of organic matter and release of metabolic production, and the ammonium bottom flux was an important resource for nutrients geochemistry in the Zhujiang Estuary.

关键词： The Zhujiang Estuary sediment interstitial water nutrient salts

Impact of environmental variables on spatial and seasonal internal phosphorus loading in a mesoeutrophic lake

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International Journal of Sediment Research 2019年第1期34卷 14-26页

作者： Katarzyna Kowalczewska-Madura Ryszard Go?dyn Julia Bogucka Katarzyna Strzelczyk Department of water Protection Faculty of BiologyAdam Mickiewicz University

Strzeszynskie Lake was formerly a slightly eutrophic（meso-eutrophic） water body. The aim of the current research was to define variables on both spatial and seasonal internal phosphorus loading from bottom sediments at five stations located in zones varying in depth, oxygenation, macrophyte presence,and uses of the neighboring catchment area. Ex situ experiments done with the use of intact bottom sediment cores have shown that the highest phosphorus release occurred in the deepest part of the lake and reached 3.6 mg P/m2d under anoxic conditions during summer thermal stratification. In turn, the internal loading from littoral sediments, which were well aerated all year round, was clearly ***, phosphorus accumulation in the bottom sediment was observed to reach a maximum of 1.45 mg P/m2d in autumn. A comparison of the internal loading intensity in lake zones with different land uses of the neighboring catchment area has shown slightly higher values at stations adjacent to the forest catchment area than those used for recreation. Changes in the land use of the catchment area of Strzeszynskie Lake, especially the increase in impermeable surfaces, have led to an increased inflow of external loads after heavy rains, resulting in deterioration in water quality and a delayed increase in internal loading.

关键词： Bottom sediments interstitial water Bottom water Internal loading Sediment-water interface

REE distribution in water-sediment interface system at deep ocean floor

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Acta Oceanologica Sinica 1994年第4期13卷 519-526页

作者： Zhang Lijie Liu Jihua and Yao De ( Institute of Marine Geology, MGMR, Qingdao 266071, China)

REE concentrations and distribution patterns in the different phases of water-sediment interface system at deep ocean floor were studied on the basis of samples of bottom water, sediments, interstitial water and polymetallic nodules collected from the East Pacific Basin by R/V Haiyang 4 during HY4-871 and HY4-881Cruises. It is suggested that REE concentrations in oxic interstitial water are lower than that in bottom weter,REE contents of polymetallic nodules, except Ce, are similar to that of sediments. Bottom water, sediments and interstitial water are almost the same in REE distribution patterns. MREE enrichment relative to LREE and HREE and negative Ce anomalies, MREE earichment has been found in polymetallic nodules,and Ce shows positive anomalies. REE contents in sediments increase with depth, and the vacations of distribution patterns with depth have not been found.

关键词： The East Pacific Basin water-sediment inter face system interstitial water rare earth elements

Contents and benthic fluxes of nutrients in sediment pore water of the Southern Ocean

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Chinese Journal of Polar Science 2009年第1期20卷 40-47页

作者：扈传昱薛斌刘小涯潘建明 Lab of Marine Ecosystem and Biogeochemistry SOA.Second Institute of OceanographySOA China University of Geosciences

The concentration and profile characters of nutrients in sediment pore water of the South Ocean, sampled during the cruise of CHINARE-18 of the austral summer 2001/02 were determined. The results show that the content of SiO3-Si and NH4- N were much higher than other nutrients. The profile of SiO3-Si was characterized with sharp gradients near the sediment-water interface, profile distribution of silicate show that during the diagenetie reaction of silicate, dissolution was the main part. The organic matter decomposition was occurred under the anaerobic condition. Benthic fluxes of SiO3-Si, NH4-N were from pore water to overlying water, and regeneration of silicate and ammonium were the main part of the nutrient regeneration from the pore water of the study area.

关键词： nutrient interstitial water sediment the South Ocean.