Chemical Analysis for Ecology Department

Presentation

Le Service Commun Analysis Cfor theEcology (ACE) is located on the Star campus (Saint-Jérôme). It was set up in 2018 to provide technical and logistical support to the unit's researchers in answering ecological questions such as the impact of the anthropisation of environments or the impact of stress on the environment.

 In particular, this service uses chromatographic analysis to assess :
- the health status of environmental matrices such as water and soils by determining the ionic charge
- the potential for decomposition of organic matter from elementary analysis (C, N),
- the effect of inputs (pollutants, amendments, etc.) on the activity of micro-organisms in soils by gas chromatography (respirometry),
- the consumption of sugars, or the production of acids and ethanol, for the characterisation of biostimulants by high-pressure liquid chromatography on a specific column.

This service also offers spectrophotometric assay methods (visible) chlorophylls (a, b and c) and pheopigments for monitoring algal biomass.  

Various physico-chemical measurements (pH, conductimetry, water hardness) are also carried out by this service.

The ACE service team offers :

  • advice on sampling, sample preparation and analytical protocols,
  • the provision of equipment for carrying out routine environmental analyses,
  • training in the use of analytical equipment,
  • technology watch, with the development and optimisation of methods in line with research themes/programmes,
  • preliminary assistance in setting up scientific projects (technical feasibility, costs, etc.).

 



Instruments and techniques

The Team

Scientific manager of the ACE department
MCF-Maitre de Conferences
Technical manager of the ACE department
ITA-Engineer Administrative Technician
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Sandrine Amat
ITA-Engineer Administrative Technician
Isabelle Bombarda
MCF-Maitre de Conferences
Loris Cagnacci
ITA-Engineer Administrative Technician
Lisa Foli
ITA-Engineer Administrative Technician
Martine Martinez
ITA-Engineer Administrative Technician
Cassandra Saignol
ITA-Engineer Administrative Technician

Photo gallery

In order to guarantee the analysis of a representative fraction of a sample (soil, plant), it must be dried and then ground. For this purpose, the ACE joint service has a freeze-dryer and grinders of varying capacities.

  • Freeze-dryer

Freeze-drying removes water from samples by sublimation. This low-temperature drying process ensures that the samples are better preserved (avoiding degradation in the presence of water).

  • Ball Mill

After the freeze-drying stage, the ball mill is used to reduce the samples to powder. There are different types of bowl depending on the sample (soil, sediment, plants) and the quantity to be ground.

  • Freezer -80°C
  • Cold room 4°C

Water quality control uses a combination of techniques physico-chemical, biological, bacteriological and technological. The use of several methods provides an overview of water quality, possible sources of pollution, and potential impacts on the environment and human health. These complementary approaches guarantee rigorous monitoring and better management of water resources.

  • Determination of ion content (chloride, fluoride, phosphate, sulphate, nitrate, nitrite, calcium, ammonium, magnesium, sodium, potassium) and silica by ion chromatography (make & model: Metrohm 930 Compact IC Flex, detector: conductivity meter)

 Application examples The following are some of the most important findings: evidence of pollution due to industrial discharges; disruption of the water cycle due to poor oxygenation; changes in the algal community.

  • Determination of chlorophyll content by UV-Visible Spectrometry (make & model : Jasco V 630 double beam spectrophotometer)

Application examples Determination of chlorophylls (a, b and c) and pheopigments - algal biomass indicator, salt stress indicator.

  • Physical and chemical analyses by pHmetry, conductimetry and volumetric dosing 

Application examples Water hardness measurement

Soil health is assessed by various indicators relating to the quality of soil organic matter and the biological state of the soil. The quality of soil organic matter is traditionally assessed by determining the organic carbon and nitrogen (C/N) content of samples using gas chromatography. The biological state of the soil is assessed by measuring the activity of organisms using respirometry. In addition, near-infrared analysis of soil samples provides a better understanding of their chemical composition. This technique requires extensive sampling and statistical analysis of the data collected.

  • Determination of C and N - content Elemental Analyser (make & model : ThermoScientific FlashEA 1112 , detector : catharometer (TCD))

Application examples To determine the potential for soil degradation, the level of soil fertility, the contribution to biogeochemical cycles and the impact on ecosystem productivity.

  • Respirometry (O2/CO2) by gas chromatography (make & model : Agilent 8860 - detector: catharometer (TCD)).

Application examples Determination of microbial biomass and microbial activity in the soil, Effect of inputs on the activity of micro-organisms.

  • Qualitative and quantitative analysis of organic matter (proteins, carbohydrates, hydrocarbons, organic compounds) or inorganic. Field Near Infrared Spectrophotometer (ARCoptix Rocket) (11000 to 4000 cm-1), ARCSpectro software)

Determination of sugars, organic acids and light alcohols using high-performance liquid chromatography aims to provide valuable information on the dynamics of organic matter, the quality of the substrate for micro-organisms, and the contribution of biological processes to the cycles of essential elements. This enables an accurate assessment of ecological processes and soil fertility with a view to maximising the production of biostimulants. The aim is to take advantage of these biological processes to create products that improve plant growth and soil quality, thereby contributing to sustainable agricultural practices.

  • HPLC (make & model : Agilent 1200 series spectrophotometer, 3 detectors : DAD diode array detector (190-950nm), fluorimeter, refractometer)

Example of application Kinetic study of the consumption of sugars and the production of acids and light alcohol during the activation of fermented forest litter (LiFoFer) for the production of a biostimulant.