Excitation−emission matrix (EEM) fluorescence spectroscopy has been widely used to characterize dissolved organic matter (DOM) in water and soil. However, interpreting the >10,000 wavelength-dependent fluorescence intensity data points represented in EEMs has posed a significant challenge. Fluorescence regional integration, a quantitative technique that integrates the volume beneath an EEM, was developed to analyze EEMs. EEMs were delineated into five excitation−emission regions based on fluorescence of model compounds, DOM fractions, and marine waters or freshwaters. Volumetric integration under the EEM within each region, normalized to the projected excitation−emission area within that region and dissolved organic carbon concentration, resulted in a normalized region-specific EEM volume (Φi,n). Solid-state carbon nuclear magnetic resonance (13C NMR), Fourier transform infrared (FTIR) analysis, ultraviolet−visible absorption spectra, and EEMs were obtained for standard Suwannee River fulvic acid and 15 h...

Fluorescence excitation-emission matrix regional integration to quantify spectra for dissolved organic matter.

Biochar as a sorbent for contaminant management in soil and water: a review.

Characterization of marine and terrestrial DOM in seawater using excitation-emission matrix spectroscopy

Climate change 2014 - Synthesis Report

Rapid turnover of organic matter leads to a low efficiency of organic fertilizers applied to increase and sequester C in soils of the humid tropics. Charcoal was reported to be responsible for high soil organic matter contents and soil fertility of anthropogenic soils (Terra Preta) found in central Amazonia. Therefore, we reviewed the available information about the physical and chemical properties of charcoal as affected by different combustion procedures, and the effects of its application in agricultural fields on nutrient retention and crop production. Higher nutrient retention and nutrient availability were found after charcoal additions to soil, related to higher exchange capacity, surface area and direct nutrient additions. Higher charring temperatures generally improved exchange properties and surface area of the charcoal. Additionally, charcoal is relatively recalcitrant and can therefore be used as a long-term sink for atmospheric CO2. Several aspects of a charcoal management system remain unclear, such as the role of microorganisms in oxidizing charcoal surfaces and releasing nutrients and the possibilities to improve charcoal properties during production under field conditions. Several research needs were identified, such as field testing of charcoal production in tropical agroecosystems, the investigation of surface properties of the carbonized materials in the soil environment, and the evaluation of the agronomic and economic effectiveness of soil management with charcoal.

http://www.css.cornell.edu/faculty/lehmann/publ/BiolFertSoils%2035,%20219-230,%202002%20Glaser.pdf

Ameliorating physical and chemical properties of highly weathered soils in the tropics with charcoal – a review

Summary

Soil organic matter fractions were isolated from three soils by the application of a sequential extraction procedure employing a series of 10 mild organic solvents of different polarity.



The isolated organic materials were characterized by elemental, infrared and electron spin resonance analyses. They showed different chemical and structural properties which varied according to the progression of the solvent series, with some similarities between two successive extracts. The corresponding fractions extracted from the three soils were substantially similar to each other in chemical character. Along each series of extracts aliphaticity appeared to decrease, whilst aromaticity, polar oxygenated and nitrogenated functional groups, transition metal ion content and organic free radical concentrations increased. ESR spectra were structured and were put in four different classes, according to their characteristic resonances.



Although the yields of extracted organic material were not high, the fractions could be considered representative of the soil organic matter composition and furnish new chemical information on its nature and properties.

Chemical and spectroscopic characterization of soil organic matter fractions isolated by sequential extraction procedure.

Fluorescence Quenching and Copper Complexation by a Chestnut Leaf Litter Extract: Spectroscopic Evidence

The potential utility of fluorescence spectroscopy as a sensitive and relatively simple tool for studying the structural and functional chemistry of humic substances (HS) has been emphasized recently. The present paper is intended to provide a review, enriched with recent, unpublished data of the author and collaborators, on the status of fluorescence spectroscopy in the chemistry of HS originated from soil and related materials, such as soil organic amendants, and HS synthesized by soil microorganisms.

Fluorescence spectroscopy applied to the study of humic substances from soil and soil related systems: A review

The purpose of this presentation is to firstly provide a general survey on the various phenomena that anthropogenic organic pollutants of various nature and origin are subjected in soils and on the specific role exerted by humic substances on these processes. The presentation will then focus on adsorption/desorption of two important classes of organic pollutants, that are some representative pesticides possessing endocrine disruptor activity and some properly active endocrine disruptor compounds (EDCs), onto soil humic acids (HAs) that are the most chemically and biochemically active fractions of humic substances and natural soil organic matter.

/pdf/the-fate-of-anthropogenic-organic-pollutants-in-soil-2j6qqtzc5y.pdf

The Fate of Anthropogenic Organic Pollutants in Soil: Adsorption/Desorption of Pesticides Possessing Endocrine Disruptor Activity by Natural Organic Matter (Humic Substances)

Molecular weight distribution, analytical and spectroscopic characterization of humic fractions sequentially isolated by organic solvents from a brown coal humic acid

Nicola Senesi

Papers

Chemical and spectroscopic characterization of soil organic matter fractions isolated by sequential extraction procedure.

Fluorescence Quenching and Copper Complexation by a Chestnut Leaf Litter Extract: Spectroscopic Evidence

Fluorescence spectroscopy applied to the study of humic substances from soil and soil related systems: A review

The Fate of Anthropogenic Organic Pollutants in Soil: Adsorption/Desorption of Pesticides Possessing Endocrine Disruptor Activity by Natural Organic Matter (Humic Substances)

Molecular weight distribution, analytical and spectroscopic characterization of humic fractions sequentially isolated by organic solvents from a brown coal humic acid