Primary Production

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primary production

[′prī‚mer·ē prə′dək·shən]
The total amount of new organic matter produced by photosynthesis.

Primary Production


the phase of the production process within an enterprise during which primary materials are converted into finished products.

Primary production is carried on in primary shops. Its nature and structure depend on the particular product being produced, the type of production, and the technology employed. In machine building, for example, primary production includes the semifinished phase (casting, forging, and pressing), the processing phase (machining and machine-stamping), and the assembly phase. In metallurgy, primary production includes the smelting of cast iron in blast furnaces and of steel in steel smelting units and the manufacture of finished rolled products in rolling mills. In textile production, it includes spinning, weaving, and finishing.

Primary production may be synthetic, as when one or several types of articles, such as motor vehicles or footwear, are made from many types of raw material; or it may be analytic, as when various types of products are obtained from one type of raw material, as is the case in coking or meat packing. The direct processes typical of extractive industry and certain single-stage production sectors, in which one finished product such as bricks or cement is produced from one type of raw material, also represent a form of primary production. Primary production may be continuous, as in chemistry and metallurgy, or discontinuous, as in machine building, woodworking, and light industry. It may also be aggregated or narrowly specialized.

Primary production may be organized according to technology, so that technologically similar operations are grouped, as in casting, machine, or assembly shops. It may also be organized according to object, so that each unit engaged in primary production performs all or most of the operations required to manufacture a certain type of product, such as micrometers or reduction gears. The exact manner in which primary production is to be organized depends on the type of production, the scale on which similar products are also manufactured, and the repetition of production routines and operations.

Under present-day conditions, the level of mechanization of primary production is steadily rising. Manual and manual-mechanical processes are being replaced by mechanized and automated processes. The concentration of operations and the introduction of multiposition processing methods have combined with automation to create a basis for raising labor productivity, intensifying production, and increasing efficiency. The introduction of rotor assembly lines aids in compressing primary and intermediate processes both in space and time. The use of preprogrammed production units makes it possible to gain the advantages of automation and to switch rapidly from one type of work to another. Management is also being mechanized and automated.

Primary production is also being developed through specialization, that is, through strict allocation of a progressively more limited set of tasks to each production facility. This is related to standardization of products, parts, and production processes. Further concentration offers one promising direction for the development of primary production. This can place production on an optimal scale, one in which the introduction and efficient use of advanced methods are ensured. In many industrial sectors, primary production is coming ever closer to being continuous, which leads in turn to a reduction in production time. A smooth production flow is further enhanced by developed methods of organizing production and the introduction of operational control and monitoring by computer.

Primary production accounts for the greatest share of total production costs. For its normal functioning, such factors as repair services, tools, and energy must be efficiently provided. In certain industrial sectors, a comprehensive technology that encompasses every process of production is being developed.


References in periodicals archive ?
We estimated above ground net primary productivity (ANPP) and litter abundance by clipping a 10 cm X 100 cm strip in each experimental plot during the second week of Oct.
Bondeau et al., "Comparing global models of terrestrial net primary productivity (NPP): Overview and key results," Global Change Biology, vol.
Ito, "A historical meta-analysis of global terrestrial net primary productivity: are estimates converging?" Global Change Biology, vol.
An alternative approach may be achieved via genetic solutions to environmental constraints that result in an increase in net primary productivity. Engineered soils, and in particular soil inversion, offer landholders an effective method for the management of weed seed-banks and surface non-wetting.
Net primary productivity of terrestrial communities: prediction from climatological data.
Using litterfall and wood production data, aboveground net primary productivity (ANPP) (g [m.sup.-2] [yr.sup.-1]) for each plot was estimated using the following equation (Whittaker and Woodwell 1968):
If 80 percent of world's population could survive the initial carnage of a strategic nuclear battle, Harwell says, it's important to know whether the net primary productivity of plant systems would be able to sustain them.
"Our study shows the extent and severity of land degradation measured in terms of loss of net primary productivity, making allowance for climatic variability," he added.
An extensive compilation of nearly 700 field estimates of net primary productivity of natural and agricultural ecosystems worldwide was synthesized in Germany in the 1970s and early 1980s.
A generalized, lumped-parameter model of photosynthesis, evapotranspiration and net primary productivity in temperate and boreal forest ecosystems.
Net primary productivity, turnover and efficiencies of energy capture and water use.