Comparative analysis of hydrologic signatures in two agricultural watersheds in east-central Illinois: legacies of the past to inform the future

Abstract

Abstract. Historically, the central Midwestern US has undergone drastic anthropogenic land use change, having been transformed, in part through government policy, from a natural grassland system to an artificially drained agricultural system devoted to row cropping corn and soybeans. Current federal policies are again influencing land use in this region with increased corn acreage and new biomass crops proposed as part of an energy initiative emphasizing biofuels. To better address these present and future challenges it is helpful to understand whether and how the legacies of past changes have shaped the current response of the system. To this end, a comparative analysis of the hydrologic signatures in both spatial and time series data from two central Illinois watersheds was undertaken. The past history of these catchments is reflected in their current hydrologic responses, which are highly heterogeneous due to differences in geologic history, artificial drainage patterns, and reservoir operation, and manifest temporally, from annual to daily timescales, and spatially, both within and between the watersheds. These differences are also apparent from analysis of the summer low flows, where the more tile-drained watershed shows greater variability overall than does the more naturally drained one. In addition, precipitation in this region is also spatially heterogeneous even at small scales, and this, interacting with and filtering through the historical modifications to the system, increases the complexity of the problem of predicting the catchment response to future changes.

What is the source of baseflow in agriculturally fragmented catchments? Complex groundwater/surface‐water interactions in three tributary catchments of the Wabash River, Indiana, USA

“…The hydrological and ecological functioning of agricultural and agriculturally fragmented watersheds is very different than undisturbed watersheds (Fenelon, ; Poff, Bledsoe, & Cuhaciyan, ; Pyron & Neumann, ; Sui, ). For example, the hydrological behaviour of many watersheds in the Midwestern United States has been altered by the installation of subsurface tile‐drain systems, and these systems have in turn impacted basin‐scale nutrient export (Buda, Williard, Schoonover, & Srinivasan, ; Haygarth & Jarvis, ; Linard, Wolock, Webb, & Wieczorek, ; McCorvie & Lant, ; Pyron & Neumann, ; Sheler, ; Sloan, Basu, & Mantilla, ; Smith, ; Tomer, Meek, Jaynes, & Hatfield, ; Van Meter, Basu, Veenstra, & Burras, ; Wagner, Vidon, Tedesco, & Gray, ; Yaeger, Sivapalan, McIsaac, & Cai, ). Installations of tile drains increased dramatically in Indiana following the American Civil War in the late 1860s (Billingsly, ) and it is estimated that 50% to 75% of the agricultural land in northern Indiana today is artificially drained (Feick, Siebert, & Döll, ; Sui, ; Tomer et al, ).…”

“…Installations of tile drains increased dramatically in Indiana following the American Civil War in the late 1860s (Billingsly, ) and it is estimated that 50% to 75% of the agricultural land in northern Indiana today is artificially drained (Feick, Siebert, & Döll, ; Sui, ; Tomer et al, ). There is abundant data linking nutrient transport from tile‐drained Midwestern watersheds to the nutrient load of the Mississippi River and its subsequent impact on the Gulf of Mexico Hypoxic Zone (Cuadra & Vidon, ; David, Drinkwater, & McIsaac, ; Donner, Kucharik, & Foley, ; Goolsby, Battaglin, Aulenbach, & Hooper, ; Royer, David, & Gentry, ; Yaeger et al, ). However, it remains unknown to what extent tile‐drain systems have impacted groundwater/surface‐water interactions, namely, baseflow generation, over the last 150 years (Meals, Dressing, & Davenport, ; Zhang & Schilling, ).…”

Bioenergy production and environmental impacts

“…As described above, growing the bioenergy crops (e.g., switchgrass or Miscanthus) will increase the amount of ET, leading to the reduction of water resource. According to Yaeger et al (2013) and Liu et al (2012), there may be potentially large negative impacts on the total water resource where the bioenergy crops plantation size is mismatched to water resource carrying capacity. This may exacerbate the water deficit of the marginal land and aggravate the water scarcity of China.…”

An integrated modeling framework for exploring flow regime and water quality changes with increasing biofuel crop production in theU.S.CornBelt

“…The effectiveness of this response to large‐scale, external hydrologic feedbacks has been limited [ Sprague et al ., ] in part due to the prevalence of tile drainage in the region [ Yaeger et al ., ], the spatial disconnect between the source of the human impacts (row crop agriculture in the Midwest) and where the external feedbacks manifest (hypoxic zone in the Gulf of Mexico) [ David et al ., ], and unintended consequences of federal bioenergy policies such as the Renewable Fuel Standard (RFS) [ Donner and Kucharik , ; Costello et al , ]. Because corn‐based ethanol constitutes the bulk of current biofuel production, the RFS mandate incentivized the cultivation of corn in the region, including on land previously held in the CRP, increasing overall fertilizer application and further confounding nutrient reduction efforts [ David et al ., ].…”