Water stability of soil aggregates and their ability to sequester carbon in soils of vineyards in Slovakia

Abstract

Soil water-stable aggregation is an important process for carbon sequestration and is a key factor controlling soil sustainability and resilience; therefore, the objectives of the present study were to (1) evaluate the differences in soil organic matter state, its specific and labile fractions and their importance in the formation of water-stable aggregates in vineyard soils differing in their genesis and texture under different soil management (vineyard rows – tilled and grassed in-between strips), and (2) estimate the ability of the vineyard soils to sequester soil organic carbon (SOC) into water-stable macro-aggregates (WSA_ma). The results showed that the WSA_ma content of the soils ranged from 47% to 97%. Soils with grasses had a higher SOC and labile carbon (C_L) contents than the bulk soil and, as a result, the higher total WSA_ma content. Soils ranged in a decreasing order in their ability to sequester SOC and C_L from bulk soil to WSA_ma: Haplic and Stagni-Haplic Luvisols > Calcaric Fluvisol = Rendzic Leptosol > Haplic and Luvi-Haplic Chernozem > Dystric and Eutric Cambisols. Our results showed that the maximum ratio of SOC content in WSA_ma to that in bulk soil was 1.0 at the maximum WSA_ma content regardless of the soil type. An increase in the ratio above this threshold value (1.0) resulted in a decrease in WSA_ma content.

Keywords:

• vineyards
• water-stable macro-aggregates
• soil organic matter
• carbon sequestration
• threshold limit

Acknowledgement

We thank Dr K. E. Dobbie from the Scottish Environment Protection Agency (SEPA) for her useful comments and help with English-language correction.

Additional information

Funding

The project was supported by the Scientific Grant Agency of the Ministry of Education of the Slovak Republic, the Slovak Academy of Sciences [grant number 2/0040/12] and the Slovak Research and Development Agency under the contract [grant number APVV-0512-12].