Changes in land use can significantly affect aggregate distribution and water
stability of structural aggregates. This study was conducted in the Kolubara
River Valley, Western Serbia, to determine the effects of land use changes on
composition and water stability of aggregates in humus horizons (0-30 cm) of
noncarbonated Gleyic Fluvisols. This study was conducted at nine sites, where
each site contained two adjacent land uses of natural grassland and arable
land which underwent crop rotation for >100 years. Soil samples were taken
from depths of 0-10, 10-20 and 20-30 cm for each land use. When the grassland
was converted into arable land, the content of the agronomically most
valuable aggregates (0.25-10 mm) of cultivated soils for a depth of 0-30 cm
was significantly reduced by 22-40%, while the percentage of cloddy
aggregates (>10 mm) increased by 41-68%, compared to grassland. In addition,
the long-term arable soil had significantly (p<0.05) lower aggregate
stability, determined by wet sieving, than grassland. The lowest aggregate
stability was found in aggregates > 3 mm. Their content is ? 2.3 times lower
in arable soil (12.6%) than in grassland (28.6%) at a depth of 0-10 cm. In
addition, meanweight diameters of dry and wetstable aggregates and structure
coefficient showed significant differences between land use at a depth of
0-30 cm. The results showed that the conversion of natural grassland to
arable land in the lowland ecosystems of Western Serbia degraded aggregate
distribution and stability.
Long-term effects of land use/land cover change on surface runoff in urban areas of Beijing, China
