This paper develops a soil conservation model that is relevant to smallholder farmers who applylittle or no fertilizer. Empirical results drawn from northern Tanzania imply that, ignoringfertility mining problem in model specification leads to overestimation of profits for farms thatapply little or no fertilizer. The model also shows that, the impact of output price on soilc...

An hypothesis, that the invasion of hawkweeds (Hierucium species) into South Island high country was triggered by fertiliser application from about 1950, is examined. Reference is made to the historical occurrence of hawkweeds in New Zealand, volumes and patterns of fertiliser application to high country, and experimental and observational information about the response of hawkweeds to soil fer...

Cover crops are essential in agricultural management and especially in organic farming for protecting the soil from erosion, competing with weeds, preventing evaporative losses and improving soil quality and fertility. The choice of cover crop species is crucial in achieving the highest level of weed suppression and soil fertility enhancement. Cover crop systems with rye or mixtures of legumes ...

Cultural methods such as crop fertilization can affect susceptibility of plants to insect pests by altering plant tissue nutrient levels. Research shows that the ability of a crop plant to resist or tolerate insect pests and diseases is tied to optimal physical, chemical and mainly biological properties of soils. Soils with high organic matter and active soil biology generally exhibit good soil...

Field experiments were conducted on-farm in the forest zone of Ghana to determine the effects of stubble mulch (in-situ residues from Mucuna pruriens var utilis or natural grass fallow) and method of land preparation on the yield of dry season tomato (Lycopersicon esculentum). Land preparation methods studied were slash burn and ridge; ridge and mulching with the existing residue; and zero till...

Ectomycorrhizae (EM) are important for the survival of seedlings and trees, but how they will react to global warming or changes in soil fertility is still in question. We tested the effect of soil temperature manipulation and nitrogen fertilization on EM communities in a high-altitude Pinus cembra afforestation. The trees had been inoculated in the 1960s in a nursery with a mixture of Suillus ...

this research was conducted in a part of the dry farming lands of the southern guilan province, aimed at examining the impact of tillage erosion on the soil displacement and consequently its productivity. in order to achieve the research aims, 18 sampling points were spotted in some different locations of the landscape in seven adjacent fields, based on the adjacency to the field ridges (border...

Recent studies in sub-Saharan Africa have shown that fertility is reduced among HIV-infected women compared with uninfected women. The size and pattern of this fertility reduction has important implications for antenatal clinic-based surveillance of the epidemic and also for estimates and projections of the demographic impact of the epidemic. This paper examines the association between HIV and ...

15/35 Abstract Crop production on smallholder agricultural land must increase considerably if the growing world population is to be fed. To achieve this, affordable soil testing methods, fertilizer recommendations and the accessibility of optimal fertilizers containing the required nutrients are required. The SoilCares mobile laboratory offers affordable soil testing using infrared spectroscopy...