Smallholder farmers in southern Africa have reported on increased labour requirements for hoe weeding due to high weed infestations in conservation farming (CF) fields. However, CF proponents claim that weed pressure and labour requirements for weeding decrease within the first three years under the recommended CF practices. An observational study was carried out during the 2008/09 cropping sea...

As mining operations go deeper, working conditions become more severe because of high temperature and moisture. The major heat source in deep mines is geothermal heat from the strata. Apart from the rise in rock temperature occurring as working depths increase, the air in mines is also affected by other heat sources. In modern face workings, for example, outputs of between 1,000 and 2,000 kWh m...

BACKGROUND Archaeobotany, the study of plant remains from sites of ancient human activity, provides data for studying the initial evolution of domesticated plants. An important background to this is defining the domestication syndrome, those traits by which domesticated plants differ from wild relatives. These traits include features that have been selected under the conditions of cultivation. ...

In the majority of modern forest management systems, mature trees are harvested above the root collar, leaving stumps in the ground. Due to widespread concern about climatic change caused by anthropogenic emissions of greenhouse gases, increasing prices of fossil fuels and a desire to improve energy security, there is a growing interest in the exploitation of alternative sources of energy, incl...

Background: Soils contain the greatest terrestrial carbon (C) pool on the planet. Since approximately 12 % of soil C is held in cultivated soils, management of these agricultural areas has a huge potential to affect global carbon cycling; acting sometimes as a sink but also as a source. Tillage is one of the most important agricultural practices for soil management and has been traditionally un...

Keller, T. 2004. Soil Compaction and Soil Tillage Studies in Agricultural Soil Mechanics Doctoral dissertation. ISSN 1401-6249, ISBN 91-576-6769-1 This thesis deals with various aspects of soil compaction due to agricultural field traffic, the draught force requirement of tillage implements and soil structures produced by tillage. Several field experiments were carried out to study the mechanic...

Land degradation and desertification (LDD) has gained worldwide policy attention due to decline in land quality the resultant economic burden accrued upon a vast population reliant on land-based natural capital. In India, impacts are becoming apparent as 24 out of 29 states have been experiencing LDD since early 2000s. Here, we adopt mixed-method approach combining hierarchical cluster analysis...

Tillage may in ̄uence nitrate losses from agricultural soils. Losses of nitrate were measured in drain ̄ow at 60 cm depth and in combined surface runoff and inter ̄ow in the A horizon (ˆsurface layer ̄ow) on hydrologically sealed plots with a two-year comparison (1988±1990) of shallow-tine cultivation vs. mouldboard ploughing. Ploughing increased concentrations and loadings of nitrate in drain ̄ow ...

Sheep farming was a profitable business for the bishops of Winchester before the Black Death. Evidence from the manor of Crawley demonstrates that investment in the management of the flock peaked in the early fourteenth century. Elsewhere on the estate, improvements in the provision of sires, housing, feeding, medicaments and the labour supply have been shown to impact favourably upon fertility...