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Precision mapping
(2000)
The nondestructive determination of plant total dry matter (TDM) in the field is greatly preferable to the harvest of entire plots in areas such as the Sahel where small differences in soil properties may cause large differences in crop growth within short distances. Existing equipment to nondestructively determine TDM is either expensive or unreliable. Therefore, two radiometers for measuring reflected red and near-infrared light were designed, mounted on a single wheeled hand cart and attached to a differential ...
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Root-induced increases in soil pH and nutrient availability to field-grown cereals and legumes on acid sandy soils of Sudano-Sahelian West Africa
(2000)
A field experiment with millet (Pennisetum glaucum L.), sorghum [Sorghum bicolor (L.) Moench], cowpea (Vigna unguiculata L.) and groundnut (Arachnis hypogeae L.) was conducted on severely P-deficient acid sandy soils of Niger, Mali and Burkina Faso to measure changes in pH and nutrient availability as affected by distance from
the root surface and by mineral fertiliser application. Treatments included three rates of phosphorus (P) and four levels of nitrogen (N) application. Bulk, rhizosphere and rhizoplane soils ...
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Mechanisms of residue mulch-induced cereal growth increases in West Africa
(2000)
The use of crop residues (CR) has been widely reported as a means of increasing crop yields across West Africa. However, little has been done to compare the magnitude and mechanisms of CR effects systematically in the different agro-ecological zones of the region. To this end, a series of field trials with millet (Pennisetum glaucum L.), sorghum [Sorghum bicolor (L.) Moench], and maize (Zea mays L.) was conducted over a 4-yr period in the Sahelian, Sudanian, and Guinean zones of West Africa. Soils ranged in pH from ...
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Merkmale "guter Supervision"
(2000)
Als Merkmale "guter Supervision" wurden in einer empirischen Studie vor allem die strikte Aufgabenorientierung der Supervisoren, die umfassende sozialwissenschaftliche Fundierung ihrer Interventionen, ihre Triangulierungskompetenz und die Ressourcenorientierung herausgearbeitet. Den Supervisionsexperten gelingt es, die Abstinenz in der Supervision und die Handhabung von Übertragung und Widerstand feldspezifisch und gegenstandsangemessen zu variieren. Erfolgreiche Supervisoren, so ließ sich zeigen, vereinen Fähigkeiten ...
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Maya Nadig im Gespräch
(2000)
Prof. Dr. Maya Nadig (Universität Bremen, Fachbereich Kulturwissenschaft) im Gespräch mit Dr. Wolfgang Hegener am 2. Mai 1998 in Berlin. Das Interview wurde zusammen mit Dr. Heidi Möller geplant und bearbeitet.