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Aufsatz
Causes of legume-rotation effects in increasing cereal yields across the Sudanian, Sahelian and Guinean zone of West Africa
(Horst, Walter J. (u.a.) (Hrsg.), 2001)
On-farm experiments and pot trials were conducted on eight West African soils to explore the mechanisms governing the often reported legume rotation-induced cereal growth increases in this region. Crops comprised pearl millet (Pennisetum glaucum L.), sorghum (Sorghum bicolor Moench), maize (Zea mays L.), cowpea (Vigna unguiculata Walp.) and groundnut (Arachis hypogaea L.). In groundnut trials the observed 26 to 85% increases in total dry matter (TDM) of rotation cereals (RC) compared with continuous cereals (CC) in ...
Dissertation
Effects of different tillage treatments on labile soil organic matter pools and stabilization processes
(2013-06-26)
An improved understanding of soil organic carbon (Corg) dynamics in interaction with the mechanisms of soil structure formation is important in terms of sustainable agriculture and reduction of environmental costs of agricultural ecosystems. However, information on physical and chemical processes influencing formation and stabilization of water stable aggregates in association with Corg sequestration is scarce. Long term soil experiments are important in evaluating open questions about management induced effects on ...
Aufsatz
Effects of changing water availability on land use in irrigated mountain oases of Al Jabal Al Akhdar, northern Oman
(2014)
In Oman, during the last three decades, agricultural water use and groundwater extraction has dramatically increased to meet the needs of a rapidly growing population and major changes in lifestyle. This has triggered agricultural land-use changes which have been poorly investigated. In view of this our study aimed at analysing patterns of shortterm land-use changes (2007-2009) in the five irrigated mountain oases of Ash Sharayjah, Al’Ayn, Al’Aqr, Qasha’ and Masayrat ar Ruwajah situated in the northern Oman Hajar ...
Aufsatz
Cereal/legume rotations affect chemical properties and biological activities in two West African soils
(2001)
A more widespread use of cereal/legume rotations has been suggested as a means to sustainably meet increasing food demands in sub-Saharan West Africa. Enhanced cereal yields following legumes have been attributed to chemical and biological factors such as higher levels of mineral nitrogen (Nmin) and arbuscular mycorrhizae (AM) but also to lower amounts of plant parasitic nematodes. This study was conducted under controlled conditions to examine the relative contribution of AM, plant parasitic nematodes and increased ...
Aufsatz
Changes in amino acid enantiomers and microbial performance in soils from a subtropical mountain oasis in Oman abandoned for different periods
(2003)
An important feature of maintaining the agricultural stability in millennia-old mountain oases of northern Oman is the temporary abandonment of terraces. To analyse the effects of a fallow period on soil microbial performance, i.e. microbial activity and microbial biomass, samples of eight terrace soils abandoned for different periods were collected in situ, assigned to four fallow age classes and incubated for 30 days in the laboratory after rewetting. The younger fallow age classes of 1 and 5 years were based on ...
Aufsatz
Cereal/legume rotation effects on rhizosphere bacterial community structure in West African soils
(2003)
The increased use of cereal/legume crop rotation has been advocated as a strategy to increase cereal yields of subsistence farmers in West Africa, and is believed to promote changes in the rhizosphere that enhance early plant growth. In this study we investigated the microbial diversity of the rhizoplane from seedlings grown in two soils previously planted to cereal or legume from experimental plots in Gaya, Niger, and Kaboli, Togo. Soils from these legume rotation and continuous cereal plots were placed into containers ...
Dissertation
Streu- und Feuchtwiesen im Kempter Wald
(2007-08-22)
Der Kempter Wald ist aufgrund seiner großflächigen prioritären Lebensräume - den Hoch- und Übergangsmooren - aber auch den landesweit selten gewordenen und durch Nutzungsaufgabe bedrohten Streuwiesen und Flachmoorgesellschaften ein Landschaftsraum von herausragender naturschutzfachlicher Bedeutung. Ausgehend von der nach wie vor aktuellen Debatte um die Schutzgebietsausweisung im Kempter Wald wurde auf dem Gebiet der Marktgemeinde Unterthingau und der Gemeinde Kraftisried die vorhandene Grünlandvegetation auf ...
Aufsatz
Agricultural, architectural and archaeological evidence for the role and ecological adaptation of a scattered mountain oasis in Oman
(2005)
The recent discovery of the monumental 5000 years old tower tombs on top of the up to 1850 m high Shir plateau has raised numerous questions about the economic and infrastructural basis of the agro-pastoral-piscicultural society which likely has constructed them. The scattered oasis settlement of Maqta, situated just below the towers in a rugged desert environment has therefore been studied from 2001 to 2003 to understand its prehistoric and present role along the ancient trade route which connected the inner-Omani ...
Dissertation
Land tenure in a changing climate
(2023)
Climate change and extreme weather have far-reaching impacts on agriculture. They do not only affect agricultural production, but also fundamental assets that shape agricultural livelihoods. In this dissertation, I study the relation of weather and climate with agricultural land tenure in low- and middle-income countries. Secure access to land is of vital importance for farmers, but insecure tenure is a reality for millions of farmers around the globe. They are unsure whether they will be able to continue farming ...
Aufsatz
Effects of post-harvest treatments on the carbohydrate composition of yacon roots in the Peruvian Andes
(2004)
Yacon (Smallanthus sonchifolius [Poepp. & Endl.] H. Robinson) is an under-exploited native root crop of the Andes, which stores oligofructans (fructo-oligosaccharides, FOS) as its main component of dry matter (DM). FOS are of increasing economic interest because of their low caloric value in human diets and bifidogenic benefits on colon health. Two on-farm experiments were conducted to: (i) determine the effect of shaded, short-term storage at 1990 and 2930 m a.s.l. in the Andean highlands; and (ii) address the effects ...