The Great Plains

Hard red winter (HRW) is an important bread wheat that accounts for more than 40% of the United States wheat crop and wheat exports. This fall-seeded wheat is produced in the Great Plains, which extend from the Mississippi River west to the Rocky Mountains, and from the Dakotas and Montana south to Texas. Significant quantities are also produced in California. HRW has moderately high protein content, usually averaging 11—12%, and good milling and baking characteristics. 

Table 3. Coproduct Yields From the Great Plains Plant ...

A commercial-scale SNG plant, the Great Plains Plant in North Dakota, was actually built and operated for several years using a scheme based on coal. However, upon termination of the government subsidy, the plant s owner, ANR Inc., found it uneconomical to continue plant operation and shut down the plant in the late 1980s. 

The Lurgi process has been the most commercially accepted gasification method since its commercialization in 1936, and is used in the large plants in South Africa, in modified designs in Germany, and in the United States for the Great Plains faciUty (25,49,50). 

Seleniferous formations occur in the Great Plains region from Canada to Mexico, accounting for > 700,000 km2 of the western U.S. Seleniferous soils are frequently associated with Se-containing geological formations (Boon, 1989). As discussed above, seleniferous formations occur in North Dakota, South Dakota, Montana, Wyoming, Colorado, Kansas, and New Mexico. Some soils derived from Se-rich parent materials, such as Cretaceous shales of the middle-western United States, have > 10 mg/kg Se and sometimes exceed 50 mg/kg (Reeves and Baker, 2000). 

Parton, W.J., Schimel, D.S., Cole, C.V., Ojima, D. 1987. Analysis of factors controlling soil organic matter levels in the Great Plains grasslands. Soil Science Society of America Journal, 51, 1173-1179,... 

The United States has two commercial facilities that convert coal to fuels or chemicals via a syngas intermediate. The Great Plains Synfuels... 

Conservation agroecosystems developed in the Great Plains of the U.S. to control soil erosion are characterized by the presence of varying quantities of plant residues on the soil surface. This residue mulch protects the soil from the erosive forces of wind and water, resulting in improved stream water quality and soil conservation. Conservation tillage systems also help maintain soil productivity and reduce energy requirements of crop production (15). However, crop yield reduction has been observed with conservation wheat production in some areas of the U.S. (16-18) and with rice culture in the Far East (, 20). 

The size distribution of soil aerosol varies spatially, being relatively coarser at the great plains sites in Montana and the Dakotas, and finer in Utah and far western Montana. 

A study of 19 larger meteorites from the Great Plains of the United States indicated a shorter mean residence time of 5200 years. Meteorites that fall in wetter climates typically do not last as long. 

The system considered here is the Lurgi dry ash coal gasification process as used at SASOL in the Republic of South Africa and proposed for use at the Great Plains gasification project in North Dakota (2). The important steps in the process as far as... 

Millions of years ago, the Great Plains of the United States were ocean. As sea levels fell and at the same time the North American continent rose, many isolated pockets of seawater, called saline lakes, formed. Over time, these lakes evaporated, leaving behind the solids that had been dissolved in the seawater. Most abundant was sodium chloride, which collected in cubic crystals referred to by mineralogists as the mineral halite. When conditions were right, halite crystals like the ones in this chapter s opening photograph would grow to be several centimeters across. 

As is shown in Figure 19.31, most of the wind resources in the United States are concentrated in the northern Great Plains. The U.S. Department of Energy estimates that more than all of the nations electricity needs could be met if the wind in these states were fully exploited. Within a couple of decades, most wind-rich states of the Great Plains will likely exceed their demand for electricity and either export the excess or use it to create hydrogen fuel through the electrolysis of water. 

Most of the U.S. wind potential is in the Great Plains region. 

During the Tertiary period which dates back approximately 65 million years. Deposits include the sub-bituminous coal and lignite beds in the Great Plains Province, which includes northeastern Wyoming, eastern Montana, western North Dakota, and northwestern North Dakota. 

Figure 6.2. (A) Variations in %N (which is proportional to C density) with precipitation along the 11 °C isotherm in the Great Plains of the United States. The humidity factor (NSQ, Niederschlag-Sattigungsdefizit from the German, or Meyer s quotient) is the total annual precipitation (mm) divided by the absolute saturation deficit of air (mm mercury). All soils were developed on loess deposits from the last glacial maximum. (B) Change in %N with precipitation along the 19 °C isotherm. Note that relative C density (estimated by assuming that the C/N ratio of SOM is fairly constant) is lower at higher mean annual temperature. Reprinted with permission from Jenny, H. (1941). Factors of Soil Formation, Dover Publications, New York.

Atrazine and Oil In the western part of the Com Belt and the Great Plains, the agricultural extension service promoted the practice of applying a mixture of a lower rate of atrazine and oil in an early postemergence spray (when weeds hrst appeared). A highly refined crop oil was used, similar to that used in fruit-tree sprays. The practice was adopted extensively, especially in the Northern states to reduce the cost of herbicide treatment and lessen the potential for carryover. 

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