Effects of peat drainage on labile organic carbon and water repellency in NE Poland

Authors : Barbara KALISZ, Andrzej LACHACZ, Roman GLAZEWSKI

Pages : 20-27

Doi:10.3906/tar-1402-66

View : 15 | Download : 9

Publication Date : 2015-02-01

Article Type : Research Paper

Abstract :Hot and cold water-extractable organic carbon insert ignore into journalissuearticles values(HWC and CWC, respectively); fractions, as good indicators of organic matter quality, as well as water repellency insert ignore into journalissuearticles values(WDPT test); and state of secondary humification were analyzed in topsoil samples of peatland drained for agricultural purposes 160 years ago. The examined sites insert ignore into journalissuearticles values(drained and used as grassland); at the peatland had been affected by the moorsh-forming process. During this process, intense mineralization and secondary humification of organic matter took place. The state of transformation of organic soils varied from weak to complete degradation. The HWC contents ranged between 2.623 and 3.572 g kg-1 in field-moist samples and 3.999 and 6.074 g kg-1 in air-dried soil samples. The CWC contents were generally lower than HWC and ranged between 0.411 and 0.535 g kg-1 in field-moist samples and 0.696 and 0.939 g kg-1 in air-dried soil samples. The examined soils were extremely water repellent when dried. The measures of transformation of peat after drainage and WDPT were not significantly correlated, but a tendency for higher values of water repellency at the site regarded as degraded was noted. Deep drainage caused an increase of HWC fraction, which in light of the moorsh-forming process should be regarded as negative. The topsoil of the peatland became dry and resistant to rewetting. However, when the ground water level is maintained at not deeper than 0.50 m, the changes in peat matter do not lead to degradation. HWC is a good measure to show differences occurring within the ecosystem. Given its correlation with state of transformation insert ignore into journalissuearticles values(W1 index); and water repellency insert ignore into journalissuearticles values(WDPT test);, HWC is a good measurement of peat quality. HWC and WDPT measurements may be helpful in determining degradation of peat soil after drainage.
Keywords : Dissolved organic carbon, fens, grasslands, moorsh forming process, hydrophobicity