25 research outputs found
Mobilidade de íons em solo ácido com aplicação de calcário, ácido orgânico e material vegetal em superfície
An Alternative Method for Deriving Optimal Fertilizer Rates
A model of fertilizer response is outlined which makes a distinction between conventional fertilizer response curves, and the relationship between product yield and maintenance application of fertilizer. The derivation of optimal fertilizer rates for two enterprises on three soil types is used to illustrate the model. A simple rule-of-thumb, which can be used to avoid some computations, is also discussed. In the Australian context, the model has implications for the derivation of optimal super-phosphate rates, and also has important implications for the type of applied super-phosphate research which should be conducted in the future
An Alternative Method for Deriving Optimal Fertilizer Rates
A model of fertilizer response is outlined which makes a distinction between conventional fertilizer response curves, and the relationship between product yield and maintenance application of fertilizer. The derivation of optimal fertilizer rates for two enterprises on three soil types is used to illustrate the model. A simple rule-of-thumb, which can be used to avoid some computations, is also discussed. In the Australian context, the model has implications for the derivation of optimal super-phosphate rates, and also has important implications for the type of applied super-phosphate research which should be conducted in the future.Demand and Price Analysis,
Economic and Biological Perspectives on Off-site Effects Associated with Soil Acidification
There is likely to be a divergence in the interests of farmers and their
neighbours or the community in the management of land and hence a greater
rate of exploitation of soil qualities than that desired by the community. This is
particularly true under current institutional arrangements with respect to nonpoint
forms of land degradation, such as soil acidification, where the property
rights of the community are weak. Hence it is important to understand the
nature and extent of off-site impacts so as to form a basis either for potential
collective action or for some form of intervention by government.
One of the objectives of this paper is to draw out the analogies between offsite
effects of a spatial nature with those of a dynamic or temporal nature with
a view to providing useful insights to biological and economic research into
the spatial off-site effects of alternative land management strategies. To make
the discussion less abstract the management of soil acidity will be used as an
example throughout the paper. To date it would seem that most biological and
economic research into this issue has focussed on the temporal dimension
Soil pH decline in relation to rotation, tillage, stubble retention and nitrogen fertilizer in S.E. Australia
Farming Options for Ameliorating Acidifying Soils in South - Eastern Australia: An Economic Assessment.
Acid and acidifying soils occur extensively in Australia. Currently, some 90 million
hectares of agricultural land in Australia is considered to be acidic and around 35
million hectares are considered to be highly acidic which is both a serious
agricultural and environmental problem. The nature, impact, and causes of soil
acidification vary across Australia, as do farming systems and the institutional and
socioeconomic issues relating to land management. In high-rainfall areas of
south-eastern Australia, managing acid soils is particularly difficult in permanent
pasture systems. In this paper, an economic analysis is made of the results of a
long-term trial (MASTER – Managing Acid Soils Through Efficient Rotations) aimed
at developing a sustainable agricultural system which can stop soil acidification and
ameliorate subsurface acidity in the 500-800 mm rainfall zone . Data from four basic
treatments (with and without lime) such as annual pastures, annual pastures / crop
rotation, perennial pastures and perennial pastures / crop rotation were analysed. We
used average crop yields and wool cuts during 1992 to 1997 and calculated gross
margins for the options. Using discounted cash flows, the economic benefits of the
different treatments were examined. The implications for farmers in those regions are
identified and explored