Fertilizer supply

Natural organic materials and various chemical byproducts represented a large proportion of the total world fertilizer supply until about the middle of the twentieth century in the later years of the century, however, the dependence shifted almost entirely to synthesized or chemically processed materials. Only by this means has it been possible to keep up with increasing populations,... 

Hearings before subcommittee of the Committee of Agriculture—House of Representatives, 81st Congress, 1949 Fertilizer Supplies. ... 

Fertilizers supply nutrients directly, make available nutrients already present, regulate, and condition the soil. They supply nutrients from a wide variety of chemical compounds and mixtures ... 

Laws, R.M. 1969. Aspects of reproduction in the African elephant, Loxodonta africana, J. Reprod. Fertil. Supply 6, 193-217. 

DdDt crises, foreign exchange shortages, and balance-of-payment difficulties led to restricted fertilizer supplies and therefore decreased fertilizer tse in many developing countries, especially in Africa and Latin America. 

Rapid devaluation of domestic currency increased the cost of imported fertilizers. Foreign exchange shortages and the dissolution of barter trade among the former communist countries affected fertilizer supplies and use in these countries. Between 1988/89 and 1992/93, fertilizer use decreased by 55% in Eurasia and 71% in... 

Foreign exchange shortages, structural adjustment programs, and drought have induced slow growth in many African countries. Debt crisis and balance-of-pay-ment difficulties have made many nations in sub-Saharan Africa dependent on foreign aid for fertilizer supplies. About two-thirds of the countries in sub-Saharan Africa... 

Overall, fertilizer supply potential is projected to increase from 134.1 million tonnes in 1994/95 to 143.4 million tonnes in 2000. Most of this increase will be contributed by an increase in nitrogen supply potential, which is projected to increase from 74.6 million tonnes in 1994/95 to 83.3 million tonnes in 2000. Because demand is projected to increase from 73.6 million tonnes to 82.1 million tonnes during the same period, nitrogen supply wriU be adequate to meet the projected demand and will leave about a 1 million tonne surplus over demand. Phosphate supply potential is projected to increase by over 2 million tonnes, whereas potash supply potential is projected to decrease by a little less than 2 million tonnes. However, because the projected demand for these two nutrients is less than the projected supply, no shortages are expected in the year 2000. On the contrary, the industry will have a surplus of 1.1 million tonnes of P2O5 and 3.6 million tonnes of K2O (see section 4.5 for details). 

Fertilizer supply-demand balances are derived from projected demand and estimated supply potential. Because capacity projections are not available for 2004/ 05, supply-demand balances for 2004/05 are based on the projected demand for 2004/05 and the estimated supply potential for 2000. This is done for two reasons First, to estimate how much additional capacity will be needed between 2000 and 2005 to meet the projected demand and in what regions. Second, what are the chances that the required additional capacity will be brought on stream ... 

Table 4.9. World Fertilizer Supply-Demand Balances, 1994/95-2004/05...

Marketing and Distribution Network and Costs - Expanded fertilizer use requires unconstrained availability of product at the farm level. Fertilizer supply at the right time and price depends on an efficient marketing and delivery system. In most developing countries these systems are underdeveloped and very costly. 

Review and delineation of present sources of fertilizer supply and an assessment of the adequacy for future consumption. 

The secondary fibre is formed later in the development of the plant and decreases the technological value of the fibre while it is strongly lignified, stiff and difficult to divide. The quality and amount of fibre in the stem is an outcome of the effects of numerous natural and agricultural factors, mostly on the cultivar (genetic potential), type of soil and fertilizer supply, sowing density, time of harvesting, etc. 

Although some studies show that kenaf requires no fertilizer supply, it seams reasonable to secure the proper nutrient balance for the entire crop rotation plaimed. The rates of N, P and K should be about 100-130, 35-50 and 110-140 kg ha respectively, depending on the soil nutrient content [47]. 

Agriculture. A fertilizer supplying ealcium and chlorine, an ingredient in herbicides,... 

In 1996 low-income countries consumed 64% of the world s nitrogen fertilizers, which provided about 55% of the total nutrient supply reaching their fields. As no less than 92% of their food proteins were derived from crops, inorganic fertilizers supplied at least half of all nitrogen in their diets. This would be an equivalent of feeding no fewer than 2.2 billion people, or roughly 40% of the world s 1996 total population. These people now depend on the Haber-Bosch synthesis for what is, as we shall see shortly, still an insufficient source of their basic food needs, that is, for their very survival. An excellent confirmation of this conclusion can be obtained by an entirely different approach. 

Netherlands between 1963 and 1965. By 1965 synthetic fertilizers supplied more than V4 of all nitrogen. Then the more normal development was cut short again in 1966 with the launching of Mao s destructive time of ideological frenzy, political vendettas, and localized civil war that became known, most incongruously, as the Cultural Revolution. 

The history of China s fertilizer production and supplies is described in CIA. 1975. People s Republic of China Chemical Fertilizer Supplies, 1949-74. Washington, D.C. CIA Chang C. 1977. Chemical fertilizer output on the Chinese Mainland. Issues Studies 13 ... 

In all double-cropping areas the replacement of green manure by a winter grain or oil crop will double, or nearly double, that land s carrying capacity, while inorganic fertilizers supply the necessary nitrogen and other nutrients. 

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