ROLE OF EUXINIC CONDITIONS IN ADSORBING ARSENIC IN ORGANIC MATTER AND PYRITE PRESERVED IN THE LOCKATONG FORMATION OF NEWARK: IMPLICATION TO THE QUALITY OF GROUNDWATER

2016 ◽  
Author(s):  
Larbi Rddad ◽  
Keyword(s):  
2002 ◽  
Vol 59 (10) ◽  
pp. 1606-1615 ◽  
Author(s):  
Martin Kainz ◽  
Marc Lucotte ◽  
Christopher C Parrish

Pathways of methyl mercury (MeHg) accumulation in zooplankton include ingestion of organic matter (OM). We analyzed fatty acid (FA) biomarkers in zooplankton to (i) investigate the effect of allochthonous and autochthonous OM ingestion on MeHg concentrations ([MeHg]) in zooplankton and (ii) examine how algal and bacterial food sources affect MeHg bioaccumulation. We partitioned bulk zooplankton samples (i.e., >500, 202, 100, and 53 μm) from Lake Lusignan (Québec) and measured [MeHg] and [FA] in each fraction. [MeHg] increased with increasing body size and was significantly higher in pelagic than in littoral macrozooplankton (>500 μm). The amount of the ingested terrestrial FA biomarker 24:0 indicated that less than 1% of the total FA in zooplankton was derived from allochthonous sources. More than 60% of the ingested FA originated from algal biomarkers and <10% from bacterial biomarkers. Relative amounts of algal-derived essential FA and bacterial FA were not associated with [MeHg] in any size fraction. In pelagic zones, the amount of MeHg in zooplankton related positively to the number of large organisms such as Calanoid copepods and Daphnia. We propose that the accumulation of MeHg in lacustrine zooplankton depends on the zooplankton habitat rather than on the quality of ingested food.


2017 ◽  
Vol 53 ◽  
pp. 253-268 ◽  
Author(s):  
Larbi Rddad

The Byram and Walls Island members in the lower and upper sections, respectively, of the Lockatong Formation in the Newark basin near the border between Pennsylvania and New Jersey were chosen to assess (i) the role of euxinic/anoxic conditions in sequestering arsenic (As) and other trace elements and (ii) the redistribution of these elements during catagenetic transformations. ἀese members are rich in organic matter and host pyrite which occurs as disseminations, small patches, and subparallel veins. ἀe sulfur isotope values of pyrite samples range between -7.5 and 0.5 ‰CDT (average = -3.5‰CDT). ἀe negative δ34S values are indicative of Bacterial Sulfate Reduction (BSR) under low temperature and euxinic/anoxic conditions. ἀe total organic carbon (TOC) values in this member ᴀuctuate between 0.5 and 2.1%. ἀese euxinic/anoxic conditions enhanced the incorporation of As and other trace elements in both organic matter and pyrite. ἀe As concentrations range from 13 to 800 mg/kg and from 1.4 to 34 mg/kg in pyrite and black shale samples, respectively. Rock Eval analyses reveal that organic matter is over-mature which altered the correlation between TOC and As. ἀe thermal cracking of organic matter resulted in the removal of these elements from organic matter and their subsequent incorporation in pyrite and bitumen. Organic matter- and pyrite-rich anoxic black shale layers and bitumen veins are potential sources of arsenic in groundwater in the Newark basin, with arsenic values that reach up to 215 μg/L.


2013 ◽  
Vol 24 (2) ◽  
pp. 127-130
Author(s):  
Elisabeta Chirila ◽  
Naliana Lupascu ◽  
Simona Raicu

Abstract Researches on the use of waste vegetable (tomatoes, peppers) and fruits (apples, plums) in order to improve the nutritional quality of the soil have been performed. The content in nitrogen, phosphorus, potassium, humus, organic matter have been analyzed in fruits and vegetable waste and also in soil before and after mixing with each waste at a ratio of 1:2.5. Analyses were done by using current analytical methods (chemical and absorption molecular spectrometry) after previous mineralization of samples with appropriate reagents. To investigate the effect of vegetable wastes on the plants growth, wheat has been planted in the witness soil sample and in the mixed soil with wastes. The nutrients concentration in vegetable waste was higher than in fruit waste (33-75%). Available phosphorus concentration increased about two times in soil with fruit waste while in the soil with vegetable the increase was of about 3 times. Potassium concentration increased about three times in soil mixed with both types of waste. Although potassium and organic matter have higher values in the soil amended with fruit waste than in the witness soil, the height of the wheat was similar with those in the control soil due to the limiting role of phosphorus.


2019 ◽  
Vol 4 (1) ◽  
pp. 1
Author(s):  
Reginawanti Hindersah ◽  
Sondi Kuswaryan

ABSTRAKSebagian sawah di  Kecamatan Sukaratu, Kabupaten Tasikmalaya tertimbun material letusan Gunung Galunggung pada 1982 sehingga kualitas sawah tidak sebaik sebelum letusan. Peningkatan kualitas tanah sawah dapat dilakukan dengan bahan organik dan pupuk hayati. Tujuan Pengabdian kepada Masyarakat ini adalah memberikan pengetahuan dasar tentang pupuk hayati kepada petani di desa Sinagar dan Linggajati serta meningkatkan keterampilan petani dalam aplikasi pupuk hayati disertai kompos. Untuk mencapai tujuan tersebut, telah dilakukan diskusi kelompok terfokus dan penyuluhan mengenai pupuk hayati, praktek pembuatan kompos dan apliksi pupuk hayati konsorsium di sawah. Hasil kegiatan ini adalah 20 orang petani memahami  peran mikroba dan pupuk kotoran ternak serta komps dalam produksi tanaman; tetapi  mereka belum mampu membuat pupuk organik sesuai standard. Hanya satu orang petani yang mengaplikasikan pupuk hayati disertai penambahan kompos di tanah sawah sehingga meningkatkan produksi sebesar 1%.  Program ini memberikan gambaran bahwa teknologi pupuk hayati dapat diadopsi oleh petani di Kecamatan Sukaratu.Kata kunci: bahan Organik;  kotoran ternak; padi sawah; pupuk hayati.ABSTRACTSome of the paddy fields in Sukaratu Sub-district, Tasikmalaya Regency were buried by Mount Galunggung's eruption material in 1982 so that the quality of soil was worse than that before the eruption. Improving the quality of paddy soil can be established with biological fertilizers. The purpose of this community service was to introduce the basic knowledge about biofertilizer to farmers in the Sinagar and Linggajati Village; and to improve farmers' skills in the application of biological fertilizers and compost. To achieve the goals, we conducted a focused group discussion, short extension program on biological fertilizers, compost production, and consortium biofertilizer application in paddy fields. The result verified that 20 farmers has knowledge about the role of beneficial microbes, manure and compost for plant production but they did not able to prepare standardized organic matter. However one farmer was interested to apply biofertilizers along with compost to paddy fields. This program illustrates that biofertilizer technology can be adopted by farmer in Sukaratu Sub-district.Key Words: biofertilizer; cattle manure; organic matter; paddy soil


2021 ◽  
Author(s):  
Marta Sebastian ◽  
Pablo Sanchez ◽  
Guillem Salazar ◽  
Xose A Alvarez-Salgado ◽  
Isabel Reche ◽  
...  

The bathypelagic ocean (1000-4000 m depth) is the largest aquatic biome on Earth but it is still largely unexplored. Due to its prevalent low dissolved organic carbon concentrations, most of the prokaryotic metabolic activity is assumed to be associated to particles. The role of free-living prokaryotes has thus been mostly ignored, except that of some chemolithoautotrophic lineages. Here we used a global bathypelagic survey of size-fractionated metagenomic and 16S (genes and transcripts) data and performed a differential abundance analysis to explore the functional traits of the different prokaryotic life-strategies, their contribution to the active microbiome, and the role that the quality of the dissolved organic matter (DOM) plays in driving this contribution. We found that free-living prokaryotes have limited capacity to uplift their metabolism in response to environmental changes and display comparatively lower growth rates than particle associated prokaryotes, but are responsible for the synthesis of vitamins in the bathypelagic. Furthermore, their contribution to the active prokaryotic microbiome increased towards waters depleted of labile DOM, which represented a large fraction of the tropical and subtropical ocean sampled stations. This points to a relevant yet overlooked role of free-living prokaryotes in DOM cycling in the vast bathypelagic desert.


2013 ◽  
Vol 21 (1) ◽  
pp. 24-33 ◽  
Author(s):  
Anne Eschen ◽  
Franzisca Zehnder ◽  
Mike Martin

This article introduces Cognitive Health Counseling 40+ (CH.CO40+), an individualized intervention that is conceptually based on the orchestration model of quality-of-life management ( Martin & Kliegel, 2010 ) and aims at improving satisfaction with cognitive health in adults aged 40 years and older. We describe the theoretically deduced characteristics of CH.CO40+, its target group, its multifactorial nature, its individualization, the application of subjective and objective measures, the role of participants as agents of change, and the rationale for choosing participants’ satisfaction with their cognitive health as main outcome variable. A pilot phase with 15 middle-aged and six older adults suggests that CH.CO40+ attracts, and may be particularly suitable for, subjective memory complainers. Implications of the pilot data for the further development of the intervention are discussed.


Sign in / Sign up

Export Citation Format

Share Document