Angebotene Diplomarbeit

Terra Preta

Bruno Glaser (08/2007-12/2007)

Betreuer: Bruno Glaser, Jago Birk

We study how pre-Colombian Anthrosols are formed and how this agricultural practices can be applied to present agriculture. Within our projects master, bachelor and diploma theses are available ranging from soil survey to soil ecology/microbiology and archaeometry. Methods include field experiments and tests, laboratory experiments, determination of soil fertility in the laboratory, biomarker analyses and compound-specific stable isotope analyses.

Wide areas of the humid tropics are dominated by highly weathered nutrient poor soils with low cation exchange capacity. In these regions slash-and-burn (shifting cultivation) is the preferential way for land clearing to convert tropical forest into agricultural fields. This procedure disturbs the nutrient cycle, leading to irreversible soil degradation within a few years. However, in Amazon more and more signs are found indicating that an intensive and sustainable agriculture was practiced during pre-Columbian periods. The most famous examples are Terra Preta soils. Terra Preta soils contain on average three times higher soil organic matter contents, 70 times more charcoal, and two to three times higher nutrient levels and a better nutrient retention capacity than surrounding infertile soils. Terra Preta soils have been under continuous agricultural use for centuries but the traditional knowledge how these soils are made is lost. Reinvention of forgotten pre-Colombian agricultural practices could be the basis for sustainable agriculture in the 21st Century to produce food for billions of people, leading to attain three Millennium Development Goals, (i) to combat desertification, (ii) to sequester atmospheric CO2 in the long term, and (iii) to maintain biodiversity hotspots such as tropical rain forests.