Cezary Kabała, Jarosław Waroszewski, Adam Bogacz and Beata Łabaz
Bartłomiej Glina, Jarosław Waroszewski and Cezary Kabała
The aim of work was to characterize the water retention in the silt-textured Luvisols with lamellic illuvial horizon (argic) that occur in the loess covered northern part of the Silesian Lowland. Soil pits were localized on the Trzebnica Hills near the villages: Machnice (profile 1), Skarszyn (profile 2) and Zaprężyn (profile 3 and 4). Profiles Machnice 1 and Skarszyn 2 were situated in the upper parts of the hills covered with beech stands with an admixture of oak, linden and maple. Profiles Zaprężyn 3 and 4 were situated in the central and lower parts of the arable slope. During the field work conducted in April 2011, 29 soil samples were collected for texture, bulk density and water properties analysis. The soils under study were characterized by texture of silt loam with lower clay content in humus horizons (.loamy silt. according to Polish classification), and higher clay content (.clayey silt.) in the illuvial and subsoil horizons. The texture of all examined profiles was dominated by the „loess“ fractions. Variable abundance of the massive lamellae causes variations in water properties of the illuvial (sub-)horizons. It was found that lamellic illuvial horizons in the loess-derived Luvisols have higher field water capacity than the homogenous illuvial horizons, apart of the clay content. There was no apparent effect of the horizon kind (homogeneous versus lamellic) on the soil bulk density. These properties mainly depended on the total clay content in a particular horizon (sub-horizon).
Katarzyna Szopka, Cezary Kabała, Anna Karczewska, Paweł Jezierski, Adam Bogacz and Jarosław Waroszewski
Differentiation of soil organic carbon (SOC) concentrations and pools in topsoil horizons of forest soils in the Karkonosze Mountains was examined in relation to environmental and human-induced factors, with special focus on altitudinal gradient, related climatic conditions, and a zonality of vegetation. The samples were collected from the forest litter and soil layers 0–10 cm and 10–20 cm, in 621 plots arranged in a regular network of monitoring established in the Karkonosze National Park. The concentrations of SOC were determined in laboratory and used for calculation of SOC pools. Four elevation zones were distinguished for analysis: 500–750 m, 750–1000 m, 1000–1250 m, and >1250 m. The concentrations of SOC in forest litter (38.3–44.1%) showed an insignificant increasing trend with altitude. The concentrations of SOC in the layers 0–10 cm and 10–20 cm, were in a very broad range 0.27–47.6%, thus indicating a high differentiation, and also tended to insignificantly increase along with altitude. The largest share of accumulated SOC pools was proved to be present in the layer 0–10 cm, except for the highest zone >1250 m in which forest litter contains slightly larger amounts of SOC. The pools of SOC accumulated in the 20 cm thick topsoil and forest litter turned out to vary considerably (3.6–58.2 kg·m−2), but the mean values and medians in particular elevation zones fall in a narrow range 10.5–11.9 kg·m−2, close to the values reported from the Alps. The lack of statistical significance of reported tendencies was explained by a monitoring sites-oriented random soil sampling, i.e. in forest stands of various age, species-composition and degradation degree.