**8. The value of the agricultural productivity**

The dominant crops in the study area include: corn (*Zea mays* L.), soybeans (*Glycine max* (L.) Merr), cotton (*Gossypium hirsutum* L.), wheat (*Triticum aestivum* L.), and rice (*Oryza sativa* L. (indica)). Other commonly cultivated crops include: potatoes (*Solanum tuberosum* L.), sweet potatoes (*Ipomoea batatas* (L.) Lam), cowpeas (*Vigna unguiculata* (L.) Walp), winter squash (*Cucurbita sp.*), sorghum (*Sorghum bicolor* L.), watermelons (*Citrullus lanatus* (Thunb) Matsum, and Nakai), peanuts (*Arachis hypogaea* L.), and a variety of vegetable crops. The study area is the most intensively cultivated region in Missouri and having the longest growing season. The area also has the highest percentage of level and tillable land, of which 60–70% is irrigated with abundant groundwater resources. Animal agriculture is very small, consisting of a few beef cattle and horse operations.

Blum et al. [13] map Sikeston Ridge as a late Wisconsin valley train having a very thin loess capping of Peoria Loess. Blum et al. [13] further attribute the Blodgett terrace as a braided terrace deposit of the Ohio River, which was entrenched within the Cache River Valley (Illinois). Based on carbon dating, Blum et al. [13] place the Charleston Fan as a Mississippi River fea-

A Large-Scale Wetland Conversion Project in Southeastern Missouri: Sustainability of Water and Soil

http://dx.doi.org/10.5772/intechopen.81254

Approximately 9000 year BCE, the Mississippi River diverted through Thebes Gap and flowed east of Sikeston Ridge [12], creating the Charleston Alluvial Fan. The study area has been extensively modified by seismic activity, featuring sand blows, sand boils, clastic dikes, liquefaction, changes in stream drainages, and subsidence [14–16]. A prominent trend of earthquake epicenters has been related to deep-seated folds and igneous intrusions [16]. Loess deposition as a capping on soils in the advance lowlands shows both the stage of devel-

ture formed during the creation of Thebes Gap (10,590 year BCE).

**10. The southeast lowlands groundwater province in Missouri**

The Southeast Lowlands Groundwater Province in Missouri (SLGP) spans 10,142 km<sup>2</sup>

contains 15.2% of the State of Missouri's groundwater, estimated at 287 billion m3

Cretaceous age McNairy aquifer crops out (at or near the surface) on the flanks of Crowley's Ridge and the Benton Hills [18]. In Stoddard County and Butler County, the McNairy formation primarily underlies alluvial materials, whereas in Dunklin County and Pemiscot County the McNairy formation is reached by wells having a depth of 600 m. In Dunklin County and Pemiscot County where wells are in thick and clean sands, the water yields range from

Creek clay formations constitute confining layers. Water from the McNairy formation in the northern regions along Crowley's Ridge are classified as iron rich, calcium-magnesium carbonate type waters, whereas waters from the McNairy formation in the southern portion of

The Wilcox Group is composed largely of Tertiary-age sands, some regions having minor inclusions of lignite and clay. The Wilcox aquifer is commonly separated into the upper and lower Wilcox aquifers because of sand grain size distribution patterns. The Wilcox aquifer overlies the Porter's Creek clay and is largely absent in northern Stoddard County and attains thicknesses greater than 427 m in Pemiscot County and Dunkin County. Water yields from

cium carbonate [18]. The Claibourn aquifer lies on the Wilcox aquifer. The Claibourn aquifer is separated in the upper, middle, and lower Claibourn aquifers, with the upper and middle Claibourn aquifers separated by a layer of thin, clayey materials that act as a confining unit

The Mississippi River Valley Aquifer (the Southeast Lowlands Alluvial Aquifer) consists of unconsolidated clay, silt, sand, and gravelly textured alluvium. Groundwater usage of the Mississippi River Valley Aquifer constitutes approximately 92% of the groundwater

. Overlying the McNairy formation, the Clayton Owl Creek and Porter's

. The water composition is calcium-magnesium carbonate or cal-

and

159

. The

and in Pemiscot County are

opment and bisequal nature of these soils [17].

southeastern Missouri are sodium chloride type waters.

the Wilcox in Stoddard Co. are approximately 2900 L min−<sup>1</sup>

570 to 2800 L min−<sup>1</sup>

approximately 6400 L min−<sup>1</sup>

(aquitard).

In southeastern Missouri, there are 4133 farms [9]. Cape Girardeau County has more than 1100 farms, thus approximately one-quarter of all farms of the eight-county region are in Cape Girardeau County. In the Mid-South region, Stoddard County has the largest number of farms, many of which are smaller farms on upland hills. The range in farm size varies from small land parcels (less than several hectares) to large farming operations (greater than 5000 hectares) [9].

The study area's population is low, with 223,000 persons. To estimate the values of the agriculture production, the annual crop production by county [9] was multiplied by commodity prices for that time [9]. The annual value of the agriculture production from cropping systems is \$1.27 billion (2016). The five-year (2012–2016) average value of production for the dominant crops include: (i) corn (\$325 million) and (ii) soybeans (\$525 million), cotton (\$200 million), rice (\$150 million), and wheat (\$75 million). For the same five-year period, the mean crop yields are (i) corn (8844 kg/ha), (ii) soybeans (2722 kg/ha), cotton (1177 kg/ha), rice (7706 kg/ha), and wheat (3965 kg/ha).

To estimate the agribusiness sales of production inputs, the product of the county harvested acreages [9] and the University Missouri crop budgets [10] were utilized. The profitability of the agribusiness sector includes: (i) seed sales for corn (\$47.38 million), soybeans (\$77.94 million), wheat (\$7.88 million), cotton (\$29.52 million), and rice (\$5.25 million), (ii) fertilizer sales for corn (\$57.8 million), soybeans (\$51.5 million), wheat (\$14 million), cotton (\$17.6 million), and rice (\$19.8 million), and (iii) herbicide sales for corn (\$14.1 million), soybeans (\$44.3 million), wheat (\$5.6 million), cotton (\$14.5 million), and rice (\$16.1 million).
