go to

Upozornění:
Používáte prohlížeč IE verze 6. Od 1. června 2012 nebude možné se s tímto prohlížečem do prostředí eAGRI přihlásit. Proveďte upgrade na IE verze min. 7 nebo použijte jiný prohlížeč (např. Mozilla Firefox nebo Google Chrome). Další informace zde.

Background and goals

 Logo projektu
   
 Logo EU  Logo EU
   


Functions of soil organic matter
Although cultivated soils in temperate region contains only around 5% of organic matter,  soil organic matter (SOM) play a key role in most soil properties and processes. It has a positive influence on water retention, soil aggregation, aeration status (soil physics), cation exchange capacity, buffer capacity for pollutants and pH and it is a source of nutrients (soil chemistry) and supports biological functioning and biodiversity (soil biology). SOM also affects the water quality because of filtering of soil leachates and influences the composition of atmosphere since SOM transformation may lead to emission of greenhouse gases (GHG), namely CO2, N2O and CH4.

Composition of SOM
SOM is composed from various fractions which have different residence time from months to centuries. It results from the fact that SOM consists of such variable materials like decomposing fresh organic matter (e.g. plant residues), microorganisms and microflora, soluble organic compounds (e.g.amino acids, carbohydrates) and colloidal organic compounds (proteins, polysacharides, humic compounds). Moreover, SOM may be bound to mineral particles which slows down its decomposition. Analytical separation and estimation of various fractions is thus important for assessment of various roles of SOM in soil functioning.

   1    2

Lack of SOM threatens soil quality
The status of SOM is influenced by natural conditions (e.g. climate, soil type, vegetation) and by human activities (e.g. soil management). According to Soil Thematic Strategy (STS, 2004), the low content of SOM along with its fast depletion, detected in many areas across Europe, presents one of the most import threats to soil quality. The document openly says that every effort has to be done to reverse this alarming trend.

Exogenous organic matter
Apart from appropriate soil management practices, application of exogenous organic matter (EOM), which includes various kinds of biowastes, was proposed as an effective tool how to increase the content of SOM. At the same time STS pointed out that application of EOM on soil has to be done under strict control. If the adverse effects of EOM on soil quality are to be minimalized, it is necessary (i) to avoid contamination of soil with heavy metals and organic pollutants potentially presents in EOM, (ii) to assure that added materials have suitable ratios among nutrients, (iii) to avoid negative effects of labil substrate surplus on soil biodiversity and (iv) to avoid increasing emission of GHGs. It is worth mentioning, that the final effect of EOM on indigenous SOM is a result of interactions among EOM composition and abiotic and biotic conditions of a given location.

 3    4    5

Overall goals of the project
Previous analysis of SOM in the Czech-Polish borderland showed the lack of SOM in arable soils. The aim of this project is to assess the current status of SOM in the region, to evaluate the amount and quality of produced EOM and to propose a set of analytical tools which can be routinely used for safe and effective application of EOM on soil.

Reference
Soil Thematic Strategy, the report of the technical working group on organic matter:
Van-Camp. L., Bujarrabal, B., Gentile, A-R., Jones, R.J.A., Montanarella, L., Olazabal, C. and Selvaradjou, S-K. (2004). Reports of the Technical Working Groups Established under the Thematic Strategy for Soil Protection. EUR 21319 EN/3, 872 pp. Office for Official Publications of the European Communities, Luxembourg.