Hansueli Pestalozzi

Bio: Hansueli Pestalozzi is an academic researcher. The author has contributed to research in topics: Soil fertility & Soil management. The author has an hindex of 1, co-authored 1 publications receiving 54 citations.

Sectoral Fallow Systems and the Management of Soil Fertility: The Rationality of Indigenous Knowledge in the High Andes of Bolivia

Abstract: In the High Andes of Bolivia, sectoral fallow systems are a common form of land use. Fields in the study area (Japo, Department of Cochabamba) are cultivated for 3 years with potatoes as the first crop and then lie fallow for 9 years. Despite the low nutrient content of the soil and the high elevation of the area (between 4000 and 4500 m above sea level), farmers achieve relatively high yields. This is explained by traditional knowledge about soil fertility management. The study focuses on nutrient dynamics over a 12-year cycle. A participatory research approach was applied to obtain information about indigenous knowledge. Soil nutrient content, phytomass, and yields were measured in 72 fields together with the farmers. Subterranean phytomass was identified as the key factor in nutrient storage during the fallow period. A multiple linear regression model shows three main factors that determine potato yields on cultivated fields. Farmers know about the nutrient dynamics of the fields; hence, culti...

Social learning towards a sustainable world

Abstract: This comprehensive volume - containing 27 chapters and contributions from six continents - presents and discusses key principles, perspectives, and practices of social learning in the context of sustainability. Social learning is explored from a range of fields challenged by sustainability including: organizational learning, environmental management and corporate social responsibility; multi-stakeholder governance; education, learning and educational psychology; multiple land-use and integrated rural development; and consumerism and critical consumer education. An entire section of the book is devoted to a number of reflective case studies of people, organizations and communities using forms of social learning in moving towards sustainability.

Geographies of Seed Networks for Food Plants (Potato, Ulluco) and Approaches to Agrobiodiversity Conservation in the Andean Countries

Abstract: This study is focused on the geographic structure of seed networks in the conservation-targeted Andean potato and ulluco crops. Results demonstrate that farmers of eastern Cuzco are dependent on multiscale networks of seed procurement that are spatially and socially differentiated at the levels of individual farmers and households, intracommunity farm units, the rural community, and groups of multiple communities. Scale-related differences exist in the seed provisioning roles of men and women farmers. Seed flows are shown to support access to diverse food plants and to shape the makeup of seed types as social-agroecological products. Negative impacts could be incurred through current approaches for in situ agrobiodiversity conservation since their models of farm zonation do not account for the multiscale geographies of seed flow in diverse Andean potatoes and ulluco.

Potato diversity at height: multiple dimensions of farmer-driven in-situ conservation in the Andes

Abstract: Botanical species and infraspecific morphological and molecular diversity represent different yet linked units of conservation. These units were used as the basis for the characterization and quantification of potato diversity at different scales of conservation: farmer family, community, geographically distanced, regional, in-situ and ex-situ subpopulations. Different methods and tools were combined for the characterization of native cultivars collected in the department of Huancavelica (Peru), including ploidy counts, morphological keys for species identification, morphological descriptor lists and genetic fingerprinting with microsatellite markers (SSR). Datasets were used for descriptive statistics, (dis)similarity analysis, dendrogram construction, cophenetic analysis, matrix correlations calculations (Mantel tests), and Analysis of Molecular Variance (AMOVA). Farmers in Huancavelica maintain high levels of species, morphological and molecular diversity. All cultivated potato species with the exception of S. phureja and S. ajanhuiri proved to be present. Tetraploid species were most abundant followed by diploids, triploids and pentaploids. Morphological characterization of 2,481 accessions belonging to 38 in-situ collections resulted in the identification of 557 morphologically unique cultivars. Genetic fingerprinting of 989 accessions belonging to 8 in-situ collections maintained by farmer families resulted in the identification of 406 genetically unique cultivars. The principal source of molecular variation is found within rather than between geographically distanced and farmer family subpopulations. The regional in-situ and a geographically restricted subset of CIP ́s core ex-situ population share 98.84% of allelic diversity. Yet, in-situ collections contain numerous unique genotypes. Species, morphological and molecular diversity of Andean potatoes in Huancavelica, central Peru