水保所知识产出(1956---)知识库

Soil aggregate stability is a feasible and effective factor to understand the complex interactions between phys-
icochemical properties and soil structure. To reveal the distributions of soil aggregate stability and its influential
factors following land use change from apple orchards abandonment and development in the Nangou watershed
of the Loess Plateau, China, this study selected five ages of apple orchards and their planting years were 1 year, 3
years, 6 years, 8 years and 10 years, one 15-year grassland developed from an apple orchard, one 15- year
grassland developed from farmland, one natural grassland and one 15-year locust. Results showed that restored
vegetation had better soil aggregate stability, soil organic carbon (SOC), and nitrogen (N) than apple orchards,
and the composition of soil particles with the best aggregate stability was clay 6%, silt 8%, and sand 86%. At a
0–10 cm soil depth, soil aggregate stability had a significant positive correlation with SOC and soil total nitrogen
(STN), and a negative correlation with NO 3
−
and NH 4
+ . In addition, vegetation diversity and coverage only
affected the soil aggregate stability of the 0–10 cm soil depth; however, soil pH, bulk density, and soil aggregate-
associated inorganic nitrogen were the main influential factors that drove the soil aggregate stability of the 0–30
cm soil depth. Further research discovered that macro-aggregate associated NO 3
− and micro-aggregate associated
NH 4
+
may be the key factors affecting the soil aggregate stability. Therefore, it is essential to further explore the
effect of soil aggregate-associated inorganic nitrogen on soil aggregate stability.