Sawdust composts in soil improvement
As indicated in a previous paper 2) the use of wood wastes in soil improvement has received considerable attention lately. Composting seems to offer large possibilities for avoiding the adverse effects of fresh sawdust and to utilize the potentialities of sawdust as a soil builder in the best fashion. The literature on composting of various waste products has been listed and reviewed very comprehensively i n t w 0 recent publications 1). The investigations rePorted here are preliminary tests of methods of composting sawdust and tests of the resulting materials on plant growth in greenhouse pot cultures.
Field plot studies with sawdust for soil improvement
SummaryHeavy application of fresh and rotted sawdust to field plots in comparison to manure and untreated control plots showed no significant difference in yields of corn over a four year period. The soil type was coarse textured and poor in nutrients at the start. However, the total yields for the rotted sawdust plots were consistently greater each year than those for the other treatments, thus possibly indicating a trend of benefit for the rotted sawdust treatments. Total yields for the fresh sawdust were close to those for the controls.Heavy applications of fertilizer, especially nitrogen, were necessary the first three years, but only a rather light application was necessary the fourth year.Soil moisture determinations indicate that all of the organic materials tend to prevent pronounced fluctuations in moisture levels, the rotted sawdust most of all.
Population and Settlement
Part 1 Population distribution: world population distribution variations in world population distribution population distribution in the Highlands and Islands population distribution in Japan population distribution in Brazil. Part 2 Population growth and movement: population structure the world population explosion variations in population growth migration why do people migrate types of migration in North and West Africa West German migration populating the USSR populating Australia attitudes to population control population and natural resources. Part 3 Settlements: location of settlement settlement types settlement functions settlement patterns South Wales valley settlements the changing village. Part 4 Urbanization: million cities world urbanization rural-urban migration in the developing world urban land use inner city problems urban transport the Tyneside metro spheres of influence changing shopping habits the Dutch Randstad Lagos - a city in the developing world new and expanding towns in the UK new settlements in developing countries green belts or red bricks? Part 5 Further studies: UK population migration Kenya's population problems Sheffield Washington New Town.