Trends in Land Use, Irrigation, and Streamflow Alteration in the Mississippi River Alluvial Plain

Abstract

The Mississippi River Alluvial Plain is a critical region for agricultural production in the United States, providing the majority of the nation's rice, catfish, and cotton. Although it is a humid region, high agricultural yields are maintained through irrigation from groundwater and surface water sources. Heavy groundwater extraction has led to cones of depression in the alluvial aquifer in both Arkansas and Mississippi. This study explores the link between increasing irrigation and streamflow alteration within the alluvial plain. Changing land use patterns were evaluated utilizing the USDA Census of Agriculture datasets to determine changes in land-use, irrigation, and crop yield from 1969 to 2017. Temporal land use patterns set the background for the analysis of sixteen long-term streamflow records from the USGS, which were assessed using the Indicators of Hydrologic Alteration (IHA) software to determine changes in low flow patterns in rivers overlying the Mississippi River Valley alluvial aquifer. Most streamflow records had significant hydrologic alteration with respect to low flow conditions, including higher frequency of low flow events, lower annual minima, or a declining base flow index. Changes in streamflow coincide with areas of massive increases in irrigated cropland area. This study provides further context for the tradeoffs between intensive agricultural production and agroecosystem sustainability.

Exploring the Regional Dynamics of U.S. Irrigated Agriculture from 2002 to 2017

“…The South Atlantic-Gulf, Upper Mississippi, Great Lakes, Texas-Gulf, and a few parts of Missouri, Lower Mississippi, and Arkansas-White-Red watersheds were mostly irrigated for 1 era, suggesting unstable irrigation, whereas most of the lands in the Lower Mississippi, California, Missouri, and Pacific Northwest watersheds were irrigated for 4 eras, indicating a strong level of irrigation stability (Figure 1a). Lower precipitation rate and availability of water for irrigation can be associated with irrigation stability in these watersheds [25,26]. 2a show the watersheds with the most substantial change in irrigated lands between 2002 and 2017.…”

“…California suffered from a prolonged drought and decreases in surface/ground water availability for irrigation throughout the study period leading to decreased irrigation, whereas the Missouri and Lower Mississippi watersheds still receive adequate ground water for irrigation. The increased number of ground water wells in Eastern Nebraska between 2002 and 2005 [8,15] and increased amount of rainfall in Lower Mississippi watershed from 1969 to 2017 [26] are driving factors for increased irrigation for these watersheds. Widespread drought in 2012 affected multiple watersheds like Missouri and California watersheds and resulted in an overall decrease in irrigation [27].…”

A Framework for Methodological Options to Assess Climatic and Anthropogenic Influences on Streamflow

“…Streamflow is one of the most important elements of the hydrological cycle and is key to understanding hydrological processes at various spatial and temporal scales under changing environments (Penny et al, 2020;Jiang et al, 2021;Porter et al, 2021;Wright et al, 2021). However, streamflow has been significantly altered by the combined effects of climate change and human activities (Liu et al, 2019;Yasarer et al, 2020;Zeng et al, 2021). Changes in two important climatic variables, precipitation, and potential evapotranspiration, jointly influence the spatial and temporal distribution patterns of water resources (Borgwardt et al, 2020).…”

Positive Mathematical Programming to Model Regional or Basin-Wide Implications of Producer Adoption of Practices Emerging from Plot-Based Research

“…The Mississippi River Valley Alluvial Aquifer (MRVAA, see figure 2) is the primary source of water for irrigation for the Lower Mississippi River Basin (LMRB) and is depleting at an unsustainable rate [2,3]. The increase in global population, the resulting growing demand for food, and the receding irrigated acreage in areas where aquifers are depleting require ever increasing levels of productivity from agricultural areas that are relatively rich in water resources such as the LMRB [4,5].…”