NATURAL ABUNDANCE OF delta C-13 AND delta N-15 IN MANAGEMENT SYSTEMS CONSERVATION IN THE CERRADO

作者：Loss Arcangelo^*; Pereira Marcos Gervasio; Perin Adriano; Cunha dos Anjos Lucia Helena

来源：Bioscience Journal, 2014, 30(3): 604-615.

• Isotopic composition
• No-tillage system
• Crop-livestock integrated system
• Soil organic matter

Different land use systems and soil management modify the isotopic signal of soil delta C-13 and delta N-15. The objective of this study was to evaluate the natural abundance the delta C-13 and delta N-15 in the soil profile in areas with different land use systems in the Cerrado of Goias State, Brazil. We evaluated two systems with crop rotation: croplivestock integration - CLI (corn + brachiaria/beans/cotton/soybean) and no-tillage system - NTS (sunflower/millet/soybean/corn). An area of natural Cerrado (Cerradao) was taken as the original condition of the soil. Soil samples were collected in layers of 0.0 to 10.0, 10.0 to 20.0, 20.0 to 30.0, 30.0 to 40.0, 40.0 to 50.0, 50.0 to 60.0, 60.0 to 80.0 and 80.0 to 100.0 cm, and the measured the delta N-15 and delta C-13 of the soil by mass spectrometer. Regarding delta C-13, it was found predominantly in the C-3 plant Cerrado influence plant and C-4 in the areas of NTS and CLI. The values presented delta N-15 an isotopic enrichment according to the increase in depth, with higher values of delta N-15 observed in cultivated areas. The replacement of the original vegetation of Cerrado for implantation of NTS and CLI led to changes in delta C-13, i.e., after 17 years of cultivation, the incorporation of carbon from grasses in these areas resulted in an increase in delta C-13 signal.. Isotopic analysis of delta N-15 indicated greater mineralization of soil organic matter with increasing soil depth and with higher rates in cultivated areas.

• 出版日期2014-6