INTRODUCTION

Climate change and land use practices have put watersheds under tremendous pressure globally, prompting the need for diversifying the actors and stakeholders involved in management (Vörösmarty et al. 2010). Lake Erie, the shallowest lake of the Great Lakes hydrological system, has become emblematic in North America: despite roughly 10 years of legislative action and billions of dollars spent to reduce nutrient inputs from intensive agriculture in the Maumee River Watershed (MRW), harmful algal blooms (HABs) still regularly plague large expanses of the lake (Fig. 1). Phosphorus (P) is frequently the focus of attention in watersheds such as the MRW (Baker and Richards 2002, Allinger and Reavie 2013, Baker et al. 2014, Ho and Michalak 2015, Matisoff et al. 2016, Muenich et al. 2016, Scavia et al. 2016, Watson et al. 2016, Baker et al. 2017) because of its well established role in the ecology of freshwater lakes (see National Research Council 1992, Carpenter et al. 1998, Carpenter et al. 1999, Osgood 2000, Bennett et al. 2001, Carpenter et al. 2001, Carpenter and Bennett 2011). However, increased frequency and severity of HABs likely stem from multiple interacting factors, including but not limited to P loading from current agricultural activity (Smith et al. 2015). Indeed, there have been calls for developing management approaches for Lake Erie and the MRW as a dynamic social-ecological system (SES; Roy et al. 2010). Currently, there is a focus on single factors such as P, which hinders restoration efforts. We join others in a call for broader analysis of Lake Erie and the MRW as a social-ecological system.

From an SES perspective, Lake Erie and the MRW comprise a complex adaptive system (CAS) where variation in system state and behavior, i.e., HABs and hypoxia, is expected a priori not to be attributable to a single factor such as human controlled P loadings (Levin et al. 2013). That is, the increasing eutrophication of Lake Erie despite decades of restoration initiatives and policies aimed at P reduction (Environment and Climate Change Canada 2017) reveals three main points: (1) the complexities of P biogeochemistry (Glendell et al. 2019, Johnston and Poulton 2019, Smith et al. 2019); (2) efficacy of and compliance with agricultural BMPs (Akkari and Bryant 2017, Jarvie et al. 2017, Macrae et al. 2019); and (3) potential influence of stochastic factors associated with climate change (Carpenter et al. 2018, Rocha et al. 2018, Das et al. 2019, Lenton 2020). Moreover, an SES perspective raises the question of whether by removing the stressor (P), we can achieve Lake Erie’s prior oligotrophic system state. Indeed, the resilience of the eutrophic state in other freshwater lakes globally, particularly in large agricultural regions, has served as a powerful reminder of how processes such as non-linearities in system responses can confound expectations that reducing P loading will improve the eutrophic status of lacustrine systems like Lake Erie (Carpenter 2005, Gordon et al. 2008, Larned and Schallenberg 2019).

Leveraging an SES perspective to improve our understanding of MRW dynamics forces us to reconcile a bewildering array of definitions, tools, frameworks, and concepts, which encompass extensions to and application of the SES analytical framework proposed by Berkes and Folke (Colding and Barthel 2019). For example, we make use of constructs such as resilience, fast and slow drivers, and CAS (Biggs et al. 2015), in order to situate HABs in the MRW as phenomena that must be analyzed at multiple geographic and temporal scales of interaction that define a complex adaptive social-ecological system. This helps us articulate a more comprehensive view of the social and ecological elements, as well as relationships potentially underpinning the behavior of the MRW and Lake Erie as an SES. Furthermore, an SES perspective presumes that system behavior and state are dynamic such that future trajectories are not only influenced by current state and conditions but are also subject to the history of the social and ecological drivers that lead up to the current state (Gunderson et al. 2017). The SES framework and associated tools expand our lens of analysis and action from a focus on managing fast variables such as P loadings in Lake Erie, for example, to consideration of the slow variables that can shape and mold the faster variables, ultimately determining system dynamics (Walker et al. 2006, 2012). Exogenous system shocks, such as human influence and climate change, further shape the interaction between fast and slow variables. Understanding the slow drivers that leverage and amplify the fast drivers, as we highlight for the MRW in our analysis, could have deep implications with respect to policymakers’ and managers’ ability to reduce negative effects such as HABs on an SES in general (Hicks et al. 2016) and the MRW specifically.

Our goal in the current study is to identify and document the social and ecological drivers operating in the MRW and Lake Erie associated with major state changes observed over the last 200 years. Our approach is inspired by a historical political ecological analysis (HPE) of the Scamandre Marsh in the Camargue Biosphere Reserve in France (Mathevet et al. 2015). Our HPE analysis of the MRW begins with the pre-European period of the MRW known as the “Great Black Swamp” (GBS; Fig. 2), tracing drivers and stages of transformation over time, culminating in the current industrial agriculture state of the MRW. An HPE supports identifying current and legacy drivers, at various scales, that need to be incorporated in models, data collection plans, policy, governance, and adaptive management strategies.

METHODS

We document five periods experienced by the MRW SES (Fig. 3) over 200 years, in which settlers have significantly modified the system changing it from a natural nutrient-filtering wetland to industrial agriculture (Table 1). We identified the periods via analysis of distinctive social, political, and ecological drivers associated with shifts in the system dynamics. Adhering to Rocha et al. (2015), drivers were identified as variables external to the feedback mechanisms of the system. To date, we are unaware of studies that have analyzed the social-ecological periods of the MRW through a historical perspective and illuminated the fast and slow variables that can provide greater focus and targeted policies for management decisions. The key unifying thread running through each period is between the need for regional economic agricultural vitality and water quality.

Period 1: pre-European settlement (early 1800s)

After the full glacial retreat but before European settlement, the MRW system was thick, dense, hardwood glacial swamp. Native Americans (e.g., Ottawa and Miami) largely lived around the perimeter of the GBS and went in primarily to harvest resources (Bogart 2015). This included ample water fowl such as swans, geese, ducks, and cranes, as well as oft-hunted buffalo (Parkins 1918). In addition to hunting-gathering activity, local tribes also participated in the sustainable cultivation and domestication of wild rice (Zizania Aquatica; de Wet and Oelke 1978) and prepared the food by the use of fire and thrashing pits (Johnson 1969).

It is clear that Native Americans had lived interdependently within the GBS, although white settlers had a different interpretation. A Moravian missionary traversed the GBS ecosystem between 1761 and 1782 and described it in his diaries as “deep swamps and troublesome marshes...where no bit of dry land was to be seen and the horses and every step wading in the marsh up to their knees [sic]” (Kaatz 1955:3-4). Given the dire conditions that the missionaries described, white settlers perceived the land as inhospitable and unsuitable for agriculture (Kaatz 1955).

However, once the early settlers learned the value of the rich soil from the local tribes and learned the strategic importance of the Maumee River, the region became the site of multiple conflicts for control. The Native Americans, British, French, early settler militias, and the U.S. Army all battled to rule the region. These conflicts (i.e., Northwest Indian War), coupled with settler colonialist policies (i.e., 1808 Treaty of Brownstone and 1830 Indian Removal Act) paved the way for structured dispossession which ultimately enabled the large-scale transfer (theft) of land into the possession of settlers (Nichols 2018, 2020) and for settlers to convert the land to agriculture.

Period 2: swamp drainage (early 1800s–early 1900s)

The MRW’s second period is marked by broad and successful efforts to drain the GBS for agricultural purposes, which historically became the main driver of developing crop production (ODNR 2009). In the 1840s, Ohio enacted the County Petition Ditch Laws (now Ohio Revised Code Chapter 6131; http://codes.ohio.gov/orc/6131). This collection of laws gave local officials authority to permit the construction of drainage ditches for the sole purpose of encouraging settlement (ODNR 2009). As a result, about 24,000 km of ditches were constructed between 1890 and 1920 to drain the entire swamp (Richards et al. 2002). Technological innovations such as the Buckeye Steam Traction Ditcher enabled the SES alteration (Fig. 4). This machine not only replaced the jobs of fifteen workers, but it would go on to drain other wetlands in the Everglades, Louisiana, and Africa (R. Edwards, unpublished manuscript).

With drainage and clearing of the swamp forest, agriculture came to dominate the landscape. From early accounts, the first agriculture in the MRW was diverse and thriving with a multitude of crops (and livestock), as described in the following excerpt:

The constituents of the soil are such as to make this a region of threat and durable fertility, with quite uniform production of the varied crops usually cultivated in this latitude, winter wheat, maize (corn), hay, potatoes, oats, rye, and barley being the principal crops. Flax, tobacco, broom-corn, sorghum, sugar beets, etc., have also been proved profitable for cultivation. Good apples, peaches, pears, plums, and grapes are produced in large quantities, and increasing attention is being given to the cultivation of various kinds of smaller fruits; also to market gardening. (Slocum 1905:3)

Wild rice grew in abundance at the Maumee River mouth, which acted as an additional sediment filtration and nutrient uptake system (Mitsch and Gosselink 2015). However, the decimation of the GBS and subsequent removal of the wild rice fields left only 5% of the original swamp landscape. Alterations in the MRW, along with other changes around the shores of western Lake Erie started to lead to the decline in water quality of the basin. Increasing areas of agricultural production and numbers of livestock served to add nutrients to the MRW landscape. The ditches accelerate water, moving nutrients more quickly downstream to Lake Erie before the system has a chance to retain them naturally. There began to be an increase of eutrophic diatoms, and for the first recorded time in history, nuisance blue-green algae began to appear (Allinger and Reavie 2013). This period changed the dominant land cover, hydrology, and eventually the soils that had developed over millennia.

Period 3: advancements in mechanization and technology (1900s–1972)

Although the mechanization of creating ditches had already been enabled, significant advancements in farm practices such as the use of tractors and fertilizer technology further transformed the MRW landscape. With the introduction of the tractor, farmers could reduce their own labor and thus expand their farm fields quickly. By the 1950s, the cost of fertilizer drastically dropped (Griliches 1958). Farmers could now purchase and apply fertilizer at a low cost to increase overall yields and profit, promoting a switch in crops from polyculture to a series of high-value monocultures, consisting of a rotation among four grains (corn, soybeans, wheat, and hay). Farmers also increased the installation of underground drainage tiles, to improve water removal resulting in higher yields, as well as the amount of sediment, and nutrients flowing into the watershed (Jarvie et al. 2017). Each of these incremental, mechanical, and technological changes contributed to a fundamental shift in the MRW, including increasing severity and frequency of HABs. The new period for the system included faster hydrological flow, increased soil erosion, and therefore nutrients released into the watershed.

The resulting governance tension between nurturing a prosperous agricultural industry and maintaining clean water downstream did not emerge immediately. Since the 1859 ditching laws, regional policies have primarily promoted agricultural expansion and prioritized the growth of the agricultural industry. It took decades for residents and policymakers to notice that a fundamental structural and functional change within the system had occurred or to recognize that the Great Black Swamp had supplied valuable ecosystem services. By 1970, the Lake had been declared dead (Steffen et al. 2014). The western basin in particular assumed a highly eutrophic state with increasingly large and toxic algal blooms (Allinger and Reavie 2013). More importantly, even while these localized stressors, such as increased land-use change, were occurring, larger-scale ecological changes were also observed. Toxic cyanobacteria were flourishing all along the Lake Erie shoreline resulting in fish kills up and down the coast (Hartig et al. 2009).

From about the 1950s into the 1970s, the noticeable decline in water quality was evident, not just within the Lake Erie area, but nationally as well. Notably, Ohio’s Cuyahoga River famously caught fire numerous times, with water quality being elevated to national consciousness through a Times Magazine article featuring the state of the river. With the rapid deterioration of water quality during this period, improving water quality became a social and political objective which characterizes the next SES period.

Period 4: water quality improvement (1972–1992)

The Great Lakes Water Quality Agreement (GLWQA) of 1972 established P discharge limitations while the federal Clean Water Act (CWA) of 1972 restricted discharges, reigning in industrial waste and untreated sewage. This marked the start of a concerted effort to improve water quality. The establishment of the CWA has received mixed reviews on overall success (see Keiser and Shapiro 2018, Shapiro 2018, Cronin 2019, Keiser et al. 2019). Most of the accomplishments of the CWA have been with respect to point sources, such as municipal and industrial discharges (Brown and Froemke 2012). However, a major limitation to the CWA is that it does not directly regulate non-point source pollution, which includes agricultural runoff. Often for political reasons, the law designed to protect the water commons excludes or exempts most agricultural activities (Angelo and Morris 2013). Therefore, the CWA leaves responsibility for mitigating or regulating non-point source and agricultural pollution to the states, which has left a policy patchwork, sometimes with divergent or competing approaches (Angelo and Morris 2013).

Ohio is seen as a national leader when it comes to agricultural legislation. However, agriculture in Ohio still has a relatively light regulatory burden other than when and how to apply fertilizer, despite a direct causal link between agriculture and algal blooms (Heisler et al. 2008, Smith et al. 2015). Further, the legislation “is not comprehensive enough to have long-term impacts on nitrogen and phosphorus pollution in Ohio lakes and waterways because the legislation only applies to a portion of the state and lacks meaningful enforcement” (Staley 2017:798). Despite the fact that the discourse in Ohio reflects a seemingly aggressive plan to curb nutrient pollution, efforts still remain aspirational rhetoric for true restoration initiatives. Although a coordinated, governance response is underway, a workable balance between allowing a thriving agricultural industry and restoring and maintaining clean water has yet to be developed.

Although cyanobacteria continued to increase, it appeared that the regulatory mechanisms were working. The size and intensity of algal blooms decreased in response to the regulatory implementation and game fish, e.g., walleye (Sander vitreus), returned in great numbers (Allinger and Reavie 2013, Levy 2017). However, the failure to fully control Lake Erie’s nutrient diet up to this point had led to a reorganization of the western basin’s ecology and ecosystem services. Microcystis, a genus with known bacterial neurotoxins, has dominated western basin HABs since 1995 (Watson et al. 2016, Levy 2017).

Period 5: biofuels (1992–present)

The early 1990s saw a confluence of drivers that added to the difficulty of limiting the nutrients flowing into Lake Erie’s western basin. The Federal Energy Policy Act of 1992 (https://afdc.energy.gov/files/pdfs/2527.pdf) called for American energy independence, through legal mandates and subsidies for clean energy. Implemented by the U.S. Department of Energy, the Energy Policy Act of 1992 resulted in the increased use of alternative fuels, such as methanol, ethanol, and other biofuels. The Renewable Fuel Standard (RFS) program created through the Energy Policy Act of 2005, and expanded under the Energy Independence and Security Act of 2007 (“the Act”, https://www.congress.gov/bill/110th-congress/house-bill/6), further required all transportation fuel sold within the United States to have a minimum amount of alternative fuel (i.e., corn-based ethanol). In addition, the Act mandated a nine-fold increase to the amount of biofuel mixed into gasoline, from 4 billion gallons in 2006 to 36 billion gallons by 2022 (see https://www.govinfo.gov/content/pkg/PLAW-109publ58/pdf/PLAW-109publ58.pdf). Given the thriving biofuel industry under RFS mandates and subsequent biofuel subsidies, commodity prices rose, incentivizing farmers to increase crop production and yields (Jarvie et al. 2015). Impacts of biofuel incentives on agricultural practices and nutrient exports from the MRW to Lake Erie are part of a national trend with persistent impacts in systems across the Corn Belt (Teter et al. 2018). This spurred land-use changes to concentrate efforts on high-value crops (Smith et al. 2015). During this period, crop rotation further decreased from four main crops (corn, soy, wheat, and hay) to two key crops (corn and soy; Muenich et al. 2016, Sekaluvu et al. 2018).

Around the same time as the biofuel expansion, Monsanto introduced Roundup Ready® corn to the market in 1996, with Roundup Ready® soybeans following a quick adoption shortly after in 1998 (Carpenter and Gianessi 1999). These genetically modified crops are specifically bred to be resistant to glyphosate herbicide, a phosphorus-based chemical. As of 2014 in the United States, about 90% of corn and 94% of soybeans are grown from glyphosate-resistant herbicide-tolerant seeds (USDA 2018). Scavia et al. (2017) demonstrated a potential link between field-applied phosphorus and the energy policies and laws that promote biofuels. Additionally, in preliminary research, Spiese et al. (2018) showed a possible correlation between the use of glyphosate and a significant increase in dissolved reactive phosphorus (DRP), a form readily available for phytoplankton consumption and hence, algal blooms. A substantial 20–25% of all DRP in the MRW is linked to the use of glyphosate and the use of Roundup Ready® crops, averaging 1/3 pound of P entering the watershed per each acre planted (Spiese et al. 2018).

Energy policy changes and the subsequent increase in corn and soybean production are not the only contributing factors that mark this fourth period. Lateral tile splitting, that is, the practice of adding additional tile drains between two already established drains for additional water removal, increased significantly. This led to tile spacing down from 30 m to 7.5 m in some places (ODNR 2009), providing additional pathways for water removal and thus increasing the water flow and nutrients into the watershed.

Another variable that is often overlooked as separate and external to current HAB governance discourse is freshwater mussels. Two highly invasive freshwater mussels—zebra mussels (Dreissena polymorpha), originating from lakes in southern Russia, and quagga mussels (Dreissena bugensis), native to the Dnieper River in the Ukraine—also compound the increase of microcystins in the western basin. Although introduced in the early 1980s via shipping ballast water, they were firmly established by the mid-1990s, dramatically changing the biotic landscape in Lake Erie and the other Great Lakes (Griffiths et al. 1991, Levy 2017). As a result of the filter-feeding mussels, the water became clearer, creating a positive feedback loop for more sunlight to enter the water column, warm the waters, and create additional nutrients for algae growth (Vanderploeg et al. 2001). However, although the mussels would consume non-toxic forms of algae, they systematically expel any toxic Microcystis, adding it back into the environment unharmed (Levy 2017). As such, the mussels effectively reject Microcystis over other phytoplankton while simultaneously creating ecological conditions that promote algal blooms, increasing the likelihood of toxic HABs (Juhel et al. 2006, Vanderploeg et al. 2013).

DISCUSSION

The MRW and the western basin of Lake Erie have shifted in structure and function over the past two centuries, steadily pushing the system to meet the needs of increased urbanization and intensive agricultural production (Cosens 2018). The increased frequency, duration, and geographic extent of HABs is a significant negative consequence that increases uncertainty about whether Lake Erie can reliably provide ecosystem services despite nearly five decades of policy and management interventions (Green et al. 2015). In the context of adaptive governance (Folke et al. 2005), our analysis raises questions about the expected efficacy of P reduction efforts as a way to reduce HABs. Like other lake SESs, the MRW is defined by a complex linkage of social, economic, ecological, legal, and policy elements (Fiksel 2006) that interact at multiple spatio-temporal scales likely to limit the success of a strategy that is unilaterally focused on controlling the fast variable (P inputs). New and legacy P loading (King et al. 2017) arising from the MRW’s highly altered hydrology (slow variable) will be shaped by factors such as climate change, and socioeconomic drivers such as national energy policies (e.g., biofuels) that can push SES structure and function through pressures on, for example, land-use practices. Such dynamics, if not accounted for in analysis, governance, and policy initiatives, will limit the success of efforts solely focused on P reduction.

Reconstructing the history of structure/function changes in the MRW helps us identify the specific actions, motivations, and stakeholders that are essential to future management opportunities and constraints. Specifically, three main periods of activity in the MRW are associated with evaluating the potential for future actions: (1) European settlement and discovery of fertile soils that enabled small-scale farming; (2) population growth and scaling up of agricultural productivity through active, large-scale draining of wetland habitats; and (3) market-driven changes in regional agricultural practices in response to national biofuel feedstock policy initiatives. Our analysis highlights, and we recommend, two factors to integrate into current MRW governance discussion. First, we must understand and take into account the significance of the altered hydrological flow as a fundamental and largely irreversible shift to the system. This is a legacy path-dependency that stakeholders effectively continue to ignore in current land-use practices. For example, lateral tile splitting is still widely used to increase the efficiency and movement of water off the land and into the lake. Actions which serve to maintain the current state of the hydrology will complicate and threaten the effectiveness and management of other drivers.

Second, governance discourse is fixated on control of the fast variable of P input. Although efforts to reduce P application, such as 2012 Great Lakes Water Quality Agreement’s U.S. Action Plan for Lake Erie (EPA 2018), are necessary, we suggest they are not sufficient because of legacy P loading (King et al. 2017). We need to approach the management of the SES as a complex adaptive system. Yet, such an approach requires models and actions that integrate across diverse stakeholders, governance structures, scales, and interests that are difficult to accommodate in a single framework (Callicott et al. 2006, Breen et al. 2018).

Although modeling frameworks are emerging (see Nelson et al. 2009, Gasparatos et al. 2011, Aragon et al. 2017, Hanes et al. 2017, Miglietta et al. 2018), data requirements, assumptions (Keiser et al. 2019), and model implementations to inform policy still present formidable challenges. Progress in managing the MRW SES will require evaluating outcomes of policy scenarios that seek to balance regional economic benefits under a shift in agricultural practices that maximize targets such as biofuel feedstock production associated with costs to water quality. As a result, our HPE leads to the following three prescriptions for action:

Reassess governance framework and laws

Folke et al. (2005) assert that polycentric governance systems provide institutions that operate at various scales a more optimal, responsive, and adaptive management framework for addressing ecological scale and local-level issues. However, even though the polycentric governance system may function better within certain boundaries, local or regional institutions can lack the authority to make cross-scale decisions (Carlisle and Gruby 2017). Further, as de Loë and Patterson (2018) and Scavia et al. (2017) suggest, and we affirm through our analysis, the western basin’s HAB problem is not just a result of and therefore cannot be controlled by, the amount of fertilizer and herbicide applied. Instead, decisions that extend beyond the typical scale and sector already considered by watershed managers, such as federal energy policies, significantly drive the HAB problem. When considering the various cross-sector scales, feedbacks, and variables, a polycentric governance approach is “necessary, but almost certainly not sufficient” (de Loë 2017:244).

Nevertheless, intra-jurisdictional governance improvements are still possible and should still be pursued. For example, the water quality regulatory landscape within Ohio is both convoluted and riddled with numerous gaps. There is a patchwork of state clean water regulatory efforts to address non-point sources while the CWA provides an inadequate governance framework to properly address HABs. A deeper assessment to bridge the gaps of local and state regulatory approaches is warranted if a holistic water governance approach is to be implemented—but some immediate “fixes” are obvious. For example, the Ohio Ditching Law of 1859 remains largely unchanged. A core tenet of this law is that to allow for optimal field drainage, the ditches shall not be obstructed in any way. The antiquated ditching laws could be revisited to integrate modern innovations, such as floating or constructed wetlands within the ditches that do not adversely impede water flow but do uptake nutrients. Even though such amendments would not be a comprehensive answer, it would contribute to the overall suite of solutions needed to make a meaningful impact.

More recently, there has been a drive to reconvert a portion of the agricultural land back into nutrient-filtering wetlands (Mitsch 2017). However, any extensive program to convert private, economically producing land back into wetland would be met with considerable political and legal resistance; the benefits of any such program would be diffuse, public, and distributed downstream whereas specific local landowners would bear almost all of the costs (Ostrom and Hess 2010, Ekbom 2011). Further, identifying causes of excessive nutrient runoff is more difficult to isolate than point sources and are therefore not well monitored or regulated by government or management agencies (Sarker et al. 2008). We liken this approach to treating the symptom and not the underlying disease.

Integrate understanding of the interaction of fast and slow drivers into proposals for action

HPE analysis helps identify historical, current, and potential future sources and areas of control and perturbation. In doing so, the requirements for management become much more explicit and focused.

In Table 2, we elucidate the various fast and slow drivers for each period. As Scavia et al. (2017) and de Loë and Patterson (2018) point out, expanded efforts to control the fast variable of P input need to account for factors driving high P demand, e.g., federal biofuel policy/incentives. Based on the system dynamic drivers, governance approaches are unlikely to find viable strategies for remediation without integration of water quality objectives with energy policy incentives.

Although the GLWQA does acknowledge legacy phosphorus, it is largely in the context of how poorly understood its role in the system is, with calls for more research. Instead, the GLWQA focuses on reducing direct fertilizer application through voluntary programs (e.g., Ohio’s 4R Certification Program). In its first two years of adoption, only 35% of the farms within the Western Lake Erie Basin enrolled in the program, resulting in 30 4R certifications affecting 950,000 hectares (Vollmer-Sanders et al. 2016). The Ohio EPA has since turned its focus to highly regulated point-source wastewater and industrial outputs. As Alexander (2018) points out, this myopic approach not only weakens the multi-stakeholder effort that focuses on a more dynamic, cross-scale approach to curbing nutrient runoff, but it also ignores the approximately 80% of agricultural non-point runoff. Therefore, as Alexander further notes, “it appears unlikely that Ohio will be able to achieve the State’s ambitious nutrient reduction goals” (2018:39).

Evaluate cross-scale connections

The MRW system is optimized for fast hydrological flow to increase agricultural yields and therefore the boundaries of the system do not match the actual scope of the system. The CWA and the suite of federal Energy Policy Acts have had profound effects on the MRW at regional and local scales. When analyzing policies that have affected drivers within the MRW, it would suit the agricultural HABs discourse in Ohio to include these higher scaled national policies and emphasize the integrated role of biofuels and HABs. Further, it is counterintuitive to think of the Clean Water Act as being detrimental to clean water. Yet, the overwhelming majority of land use within the MRW is agricultural and is therefore exempt from CWA regulation.

The Energy Policy Acts have also had profound shifts on farming practices in Ohio. Mainly, crop choices are now limited to those that can take advantage of the economic incentives for biofuels: corn and soy. Compounding the growing incentives to switch to corn and soy, Monsanto’s Roundup Ready® crops have incentivized an increase in herbicide use. Research suggests that the use of glyphosate-based Roundup Ready® seeds leads to increased glyphosate in the soil and contributes to more bio-available DRP (Brannan-Smith 2009, Spiese et al. 2018). This research implicates national policies in the resultant cross-scale linkages that have fundamentally altered the regional MRW system. As a result, appropriate boundary judgements need to be reconsidered and taken into account in MRW and Lake Erie water quality governance.

CONCLUSION

There is no panacea for addressing this highly complex, multifaceted issue, yet framing the topic and resultant regulations within a broader conceptual understanding of legacy drivers such as colonialist dispossession and other fast and slow ecological variables, cross-scale dynamics, and the regulatory imbalance of point v. non-point source governance is certainly more likely to lead to more comprehensive, measurable management outcomes.

Ultimately, the current social-ecological and political landscape is shaped, molded, and constrained by white settler colonization and legacy policies (Mathevet et al. 2015). In order to maintain the regional economic vitality of the agricultural industry, we must take into account the HPE of the MRW to inform the future restorative balance for clean water.

By understanding the past to help manage the present, discerning those reference conditions compared to present day structure and function can help set sustainability and resilience management objectives (Swetnam et al. 1999). Specifically, we need to focus the conversation on the slow hydrological flow variable and cross-scale governance linkages. However, water quality objectives cannot be reached when there is a patchwork of regulations at the state level and conflicting laws at the federal level.

Policymakers and managers are working to strike a balance between maintaining a strong agricultural industry while providing ecosystem services downstream. In order to succeed, policymakers and managers must understand the current governance boundaries, variables (both included and excluded in the current management narrative; de Loë and Patterson 2018), the historical political ecology, and the various time period reference conditions and thresholds, as they develop achievable sustainability and management objectives (Mathevet et al. 2015) in the western basin.

LITERATURE CITED

Akkari, C., and C. R. Bryant. 2017. Toward improved adoption of best management practices (BMPs) in the Lake Erie basin: perspectives from resilience and agricultural innovation literature. Agriculture-Basel 7(7):54. https://doi.org/10.3390/agriculture7070054

Alexander, R. 2018. A titled balance: emerging regulation of nutrient pollution in Ohio. Columbus Bar Lawyers Quarterly 4:37-39. https://issuu.com/columbusbarlawyersquarterly/docs/spring2018cblq/36

Allinger, L. E., and E. D. Reavie 2013. The ecological history of Lake Erie as recorded by the phytoplankton community. Journal of Great Lakes Research 39(3):365-382. https://doi.org/10.1016/j.jglr.2013.06.014

Angelo, M. J., and J. Morris. 2013. Maintaining a healthy water supply while growing a healthy food supply: legal tools for cleaning up agricultural water pollution. University of Kansas Law Review 62(4):1003-1042. https://doi.org/10.17161/1808.20264

Aragon, N. U., M. Wagner, M. Wang, A. M. Broadbent, N. Parker, and M. Georgescu. 2017. Sustainable land management for bioenergy crops. Energy Procedia 125:379-388. https://doi.org/10.1016/j.egypro.2017.08.063

Baker, D. B., R. Confesor, D. E. Ewing, L. T. Johnson, J. W. Kramer, and B. J. Merryfield. 2014. Phosphorus loading to Lake Erie from the Maumee, Sandusky and Cuyahoga rivers: the importance of bioavailability. Journal of Great Lakes Research 40(3):502-517. https://doi.org/10.1016/j.jglr.2014.05.001

Baker, D. B., L. T. Johnson, R. B. Confesor, and J. P. Crumrine. 2017. Vertical stratification of soil phosphorus as a concern for dissolved phosphorus runoff in the Lake Erie Basin. Journal of Environmental Quality 46(6):1287-1295. https://doi.org/10.2134/jeq2016.09.0337

Baker, D. B., and R. P. Richards. 2002. Phosphorus budgets and riverine phosphorus export in northwestern Ohio watersheds. Journal of Environmental Quality 31(1):96-108. https://doi.org/10.2134/jeq2002.9600

Bennett, E. M., S. R. Carpenter, and N. F. Caraco. 2001. Human impact on erodable phosphorus and eutrophication: a global perspective increasing accumulation of phosphorus in soil threatens rivers, lakes, and coastal oceans with eutrophication. BioScience 51(3):227-234. https://doi.org/10.1641/0006-3568(2001)051[0227:HIOEPA]2.0.CO;2

Biggs, R. O., G. D. Peterson, and J. C. C. Rocha. 2015. The regime shifts database: a framework for analyzing regime shifts in social-ecological systems. BioRxiv preprint 018473v1. https://doi.org/10.1101/018473

Bogart, D., 2015. “My great terror, the black swamp”: Northwest Ohio’s environmental borderland. Thesis, Miami University, Miami, Florida, USA. https://etd.ohiolink.edu/apexprod/rws_etd/send_file/send?accession=miami1429966484

Brannan-Smith, Stacy. 2009. Researchers study Roundup as possible cause of harmful algal blooms. Ohio Sea Grant News, Ohio State University, Columbus, Ohio, USA. https://ohioseagrant.osu.edu/news/2009/fe052/researchers-study-roundup-as-possible-cause-harmful-algal

Breen, S. P. W., P. A. Loring, and H. Baulch. 2018. When a water problem is more than a water problem: fragmentation, framing, and the case of agricultural wetland drainage. Frontiers in Environmental Science 6:129. https://doi.org/10.3389/fenvs.2018.00129

Brown, T. C., and P. Froemke. 2012. Nationwide assessment of nonpoint source threats to water quality. BioScience 62(2):136-146. https://doi.org/10.1525/bio.2012.62.2.7

Callicott, J. B., M. Acevedo, P. Gunter, P. Harcombe, C. Lindquist, and M. Monticino. 2006. Biocomplexity in the Big Thicket. Ethics, Place & Environment 9(1):21-45. https://doi.org/10.1080/13668790500512597

Carlisle, K., and R. L. Gruby. 2017. Polycentric systems of governance: a theoretical model for the commons. Policy Studies Journal 47(4):927-952. https://doi.org/10.1111/psj.12212

Carpenter, J., and L. Gianessi. 1999. Herbicide tolerant soybeans: why growers are adopting Roundup Ready varieties. AgBioForum 2(2):65-72. https://agbioforum.org/herbicide-tolerant-soybeans-why-growers-are-adopting-roundup-ready-varieties/

Carpenter, S. R. 2005. Eutrophication of aquatic ecosystems: bistability and soil phosphorus. Proceedings of the National Academy of Sciences 102(29):10002-10005. https://doi.org/10.1073/pnas.0503959102

Carpenter, S. R., and E. M. Bennett. 2011. Reconsideration of the planetary boundary for phosphorus. Environmental Research Letters 6(1):014009. https://doi.org/10.1088/1748-9326/6/1/014009

Carpenter, S. R., E. G. Booth, and C. J. Kucharik. 2018. Extreme precipitation and phosphorus loads from two agricultural watersheds. Limnology and Oceanography 63(3):1221-1233. https://doi.org/10.1002/lno.10767

Carpenter, S. R., N. F. Caraco, D. L. Correll, R. W. Howarth, and A. N. Sharpley. 1998. Nonpoint pollution of surface waters with phosphorus and nitrogen. Ecological Applications 8(3):559-568. https://doi.org/10.1890/1051-0761(1998)008[0559:NPOSWW]2.0.CO;2

Carpenter, S. R., J. J. Cole, J. R. Hodgson, J. F. Kitchell, M. L. Pace, D. Bade, K. L. Cottingham, T. E. Essington, J. N. Houser, and D. E. Schindler. 2001. Trophic cascades, nutrients, and lake productivity: whole-lake experiments. Ecological Monographs 71(2):163-186. https://doi.org/10.1890/0012-9615(2001)071[0163:TCNALP]2.0.CO;2

Carpenter, S. R., D. Ludwig, and W. A. Brock. 1999. Management of eutrophication for lakes subject to potentially irreversible change. Ecological Applications 9(3):751-771. https://doi.org/10.2307/2641327

Colding, J., and S. Barthel. 2019. Exploring the social-ecological systems discourse 20 years later. Ecology and Society 24(1):2. https://doi.org/10.5751/ES-10598-240102

Cosens, B. 2018. Practical panarchy for adaptive water governanance: linking law to social-ecological resilience. Springer, New York, New York, USA.

Cronin, J. 2019. The Cuyahoga fire at fifty: a false history obscures the real water crisis that never ceased. Journal of Environmental Studies and Sciences 9:340-351. https://doi.org/10.1007/s13412-019-00550-3

Das, B., N. Huth, M. Probert, L. Condron, and S. Schmidt. 2019. Soil phosphorus modeling for modern agriculture requires balance of science and practicality: a perspective. Journal of Environmental Quality 48(5):1281-1294. https://doi.org/10.2134/jeq2019.05.0201

de Loë, R. 2017. Coordinating water policies: necessary, but not sufficient. Pages 231-248 in S. Renzetti and D. P. Dupont, editors. Water policy and governance in Canada: global issues in water policy. Springer International, Cham, Switzerland. https://doi.org/10.1007/978-3-319-42806-2_13

de Loë, R. C., and J. J. Patterson. 2018. Boundary judgments in water governance: diagnosing internal and external factors that matter in a complex world. Water Resource Management 32:565-581. https://doi.org/10.1007/s11269-017-1827-y

de Wet, J. M. J., and E. A. Oelke. 1978. Domestication of American wild rice (Zizania aquatica L., Gramineae). Journal d’agriculture traditionnelle et de botanique appliquée 25(2):67-84. https://doi.org/10.3406/jatba.1978.3758

Ekbom, A. 2011. Policy instruments to reduce downstream externalities of soil erosion and surface runoff. Page 155-168 in R. A. Bluffstone and G. Köhlin, editors. Agricultural investment and productivity: building sustainability in East Africa. Resources for the future, Washington, D.C., USA.

Environment and Climate Change Canada and U.S. Environmental Protection Agency. 2017. State of the Great Lakes 2017 technical report: indicators to assess the status and trends of the Great Lakes ecosystem. Environmental Protection Agency, Washington, D.C., USA. https://binational.net/wp-content/uploads/2017/09/SOGL_2017_Technical_Report-EN.pdf

Environmental Protection Agency (EPA). 2018. U.S. action plan for Lake Erie. U.S. Environmental Protection Agency, Great Lakes National Program Office, Chicago, Illinois, USA. https://www.epa.gov/sites/default/files/2018-03/documents/us_dap_final_march_1.pdf

Fiksel, J. 2006. Sustainability and resilience: toward a systems approach. Sustainability: Science, Practice and Policy 2(2):14-21. https://doi.org/10.1080/15487733.2006.11907980

Folke, C., T. Hahn, P. Olsson, and J. Norberg. 2005. Adaptive governance of social-ecological systems. Annual Review of Environment and Resources 30:441-473. https://doi.org/10.1146/annurev.energy.30.050504.144511

Gasparatos, A., P. Stromberg, and K. Takeuchi. 2011. Biofuels, ecosystem services and human wellbeing: putting biofuels in the ecosystem services narrative. Agriculture, Ecosystems & Environment 142(3-4):111-128. https://doi.org/10.1016/j.agee.2011.04.020

Glendell, M., J. Palarea-Albaladejo, I. Pohle, S. Marrero, B. McCreadie, G. Cameron, and M. Stutter. 2019. Modeling the ecological impact of phosphorus in catchments with multiple environmental stressors. Journal of Environmental Quality 48(5):1336-1346. https://doi.org/10.2134/jeq2019.05.0195

Gordon, L. J., G. D. Peterson, and E. M. Bennett. 2008. Agricultural modifications of hydrological flows create ecological surprises. Trends in Ecology & Evolution 23(4):211-219. https://doi.org/10.1016/j.tree.2007.11.011

Green, O. O., A. S. Garmestani, C. R. Allen, L. H. Gunderson, J. Ruhl, C. A. Arnold, N. A. Graham, B. Cosens, D. G. Angeler, B. C. Chaffin, and C. Holling. 2015. Barriers and bridges to the integration of social-ecological resilience and law. Frontiers in Ecology and the Environment 13(6):332-337. https://doi.org/10.1890/140294

Griffiths, R. W., D. W. Schloesser, J. H. Leach, and W. P. Kovalak. 1991. Distribution and dispersal of the zebra mussel (Dreissena polymorpha) in the Great Lakes Region. Canadian Journal of Fisheries and Aquatic Sciences 48(8):1381-1388. https://doi.org/10.1139/f91-165

Griliches, Z. 1958. The demand for fertilizer: an economic interpretation of a technical change. Journal of Farm Economics 40(3):591-606. https://www.jstor.org/stable/1235370

Gunderson, L., B. Cosens, B. Chaffin, C. Arnold, A. Fremier, A. Garmestani, R. Craig, H. Gosnell, H. Birge, C. Allen, M. Benson, R. Morrison, M. Stone, J. Hamm, K. Nemec, E. Schlager, and D. Llewellyn. 2017. Regime shifts and panarchies in regional scale social-ecological water systems. Ecology and Society 22(1):31. https://doi.org/10.5751/ES-08879-220131

Hanes, R. J., V. Gopalakrishnan, and B. R. Bakshi. 2017. Synergies and trade-offs in renewable energy landscapes: balancing energy production with economics and ecosystem services. Applied Energy 199:25-44. https://doi.org/10.1016/j.apenergy.2017.04.081

Hartig, J. H., M. A. Zarull, J. J. H. Ciborowski, J. E. Gannon, E. Wilke, G. Norwood, and A. N. Vincent. 2009. Long-term ecosystem monitoring and assessment of the Detroit River and Western Lake Erie. Environmental Monitoring and Assessment 158:87-104. https://doi.org/10.1007/s10661-008-0567-0

Heisler, J., P. Glibert, J. Burkholder, D. Anderson, W. Cochlan, W. Dennison, C. Gobler, Q. Dortch, C. Heil, E. Humphries, A. Lewitus, R. Magnien, H. Marshall, K. Sellner, D. Stockwell, D. Stoecker, and M. Suddleson. 2008. Eutrophication and harmful algal blooms: a scientific consensus. Harmful Algae 8(1):3-13. https://doi.org/10.1016/j.hal.2008.08.006

Hicks, C. C., L. B. Crowder, N. A. J. Graham, J. N. Kittinger, and E. Le Cornu. 2016. Social drivers forewarn of marine regime shifts. Frontiers in Ecology and the Environment 14(5):252–260. https://doi.org/10.1002/fee.1284

Ho, J. C., and A. M. Michalak. 2015. Challenges in tracking harmful algal blooms: a synthesis of evidence from Lake Erie. Journal of Great Lakes Research 41(2):317-325. https://doi.org/10.1016/j.jglr.2015.01.001

Jarvie, H. P., L. T. Johnson, A. N. Sharpley, D. R. Smith, D. B. Baker, T. W. Bruulsema, and R. Confesor. 2017. Increased soluble phosphorus loads to Lake Erie: unintended consequences of conservation practices? Journal of Environment Quality 46(1):123. https://doi.org/10.2134/jeq2016.07.0248

Jarvie, H. P., A. N. Sharpley, D. Flaten, P. J. A. Kleinman, A. Jenkins, and T. Simmons. 2015. The pivotal role of phosphorus in a resilient water-energy-food security nexus. Journal of Environment Quality 44(4):1049-1062. https://doi.org/10.2134/jeq2015.01.0030

Johnson, E. 1969. Archeological evidence for utilizaton of wild rice. Science 163(3864):276-277. https://doi.org/10.1126/science.163.3864.276

Johnston, A. E., and P. R. Poulton. 2019. Phosphorus in agriculture: a review of results from 175 years of research at Rothamsted, UK. Journal of Environmental Quality 48(5):1133-1144. https://doi.org/10.2134/jeq2019.02.0078

Juhel, G., J. Davenport, J. O’Halloran, S. Culloty, R. Ramsay, K. F. James, A. Furey, and O Allis. 2006. Pseudodiarrhoea in zebra mussels Dreissena polymorpha (Pallas) exposed to microcystins. Journal of Experimental Biology 209(5):810-816. https://doi.org/10.1242/jeb.02081

Kaatz, M. R. 1955. The Black Swamp: a study in historical geography. Annals of the Association of American Geographers 45(1):1-35. https://www.jstor.org/stable/2561550

Keiser, D. A., C. L. Kling, and J. S. Shapiro. 2019. The low but uncertain measured benefits of US water quality policy. PNAS 116(12):5262-5269. https://doi.org/10.1073/pnas.1802870115

Keiser, D., and J. Shapiro. 2018. U.S. water pollution regulation over the last half century: burning waters to crystal springs? Working paper 26077. National Bureau of Economic Research, Cambridge, Massachusetts, USA. https://doi.org/10.3386/w26077

King, K. W., M. R. Williams, L. T. Johnson, D. R. Smith, G. A. LaBarge, and N. R. Fausey. 2017. Phosphorus availability in western Lake Erie basin drainage waters: legacy evidence across spatial scales. Journal of Environment Quality 46(2):466-469. https://doi.org/10.2134/jeq2016.11.0434

Larned, S. T., and M. Schallenberg. 2019. Stressor-response relationships and the prospective management of aquatic ecosystems. New Zealand Journal of Marine and Freshwater Research 53(4):489-512. https://doi.org/10.1080/00288330.2018.1524388

Lenton, T. M. 2020. Tipping positive change. Philosophical transactions of the Royal Society B 375:20190123. https://doi.org/10.1098/rstb.2019.0123

Levin, S., T. Xepapadeas, A. S. Crépin, J. Norberg, A. De Zeeuw, C. Folke, T. Hughes, K. Arrow, S. Barrett, and G. Daily. 2013. Social-ecological systems as complex adaptive systems: modeling and policy implications. Environment and Development Economics 18(2):111-132. https://doi.org/10.1017/S1355770X12000460

Levy, S. 2017. Microcystis rising: why phosphorus reduction isn’t enough to stop cyanoHABs. Environmental Health Perspectives 125(2):A34-A39. https://doi.org/10.1289/ehp.125-A34

Macrae, M., G. Ali, K. King, J. Plach, W. Pluer, M. Williams, M. Morison, and W. Tang. 2019. Evaluating hydrologic response in tile-drained landscapes: implications for phosphorus transport. Journal of Environment Quality 48(5):1347-1355. https://doi.org/10.2134/jeq2019.02.0060

Mathevet, R., N. L. Peluso, A. Couespel, and P. Robbins. 2015. Using historical political ecology to understand the present: water, reeds, and biodiversity in the Camargue Biosphere Reserve, southern France. Ecology and Society 20(4):17. https://doi.org/10.5751/ES-07787-200417

Matisoff, G., E. M. Kaltenberg, R. L. Steely, S. K. Hummel, J. Seo, K. J. Gibbons, T. B. Bridgeman, Y. Seo, M. Behbahani, W. F. James, L. T. Johnson, P. Doan, M. Dittrich, M. A. Evans, and J. D. Chaffin. 2016. Internal loading of phosphorus in western Lake Erie. Journal of Great Lakes Research 42(4):775-788. https://doi.org/10.1016/j.jglr.2016.04.004

Miglietta, P. P., S. Giove, and P. Toma. 2018. An optimization framework for supporting decision making in biodiesel feedstock imports: Water footprint vs. import costs. Ecological Indicators 85:1231-1238. https://doi.org/10.1016/j.ecolind.2017.11.053

Mitsch, W. J. 2017. Solving Lake Erie’s harmful algal blooms by restoring the Great Black Swamp in Ohio. Ecological Engineering 108:406-413. https://doi.org/10.1016/j.ecoleng.2017.08.040

Mitsch, W. J., and J. G. Gosselink. 2015. Wetlands. Fifth edition. Wiley, Hoboken, New Jersey, USA.

Muenich, R. L., M. Kalcic, and D. Scavia. 2016. Evaluating the impact of legacy P and agricultural conservation practices on nutrient loads from the Maumee River Watershed. Environmental Science & Technology 50:8146-8154. https://doi.org/10.1021/acs.est.6b01421

National Oceanic and Atmospheric Administration (NOAA). 2014. NOAA, partners predict significant harmful algal bloom in western Lake Erie this summer. NOAA, U.S. Department of Commerce, Washington, D.C., USA. https://www.noaa.gov/media-release/noaa-partners-predict-significant-harmful-algal-bloom-in-western-lake-erie-summer

National Research Council. 1992. Restoration of aquatic ecosystems: science, technology, and public policy. National Academy Press, Washington, D.C., USA. https://nap.nationalacademies.org/catalog/1807/restoration-of-aquatic-ecosystems-science-technology-and-public-policy

Nelson, G. C., M. W. Rosegrant, J. Koo, R. Robertson, T. Sulser, T. Zhu, C. Ringler, S. Msangi, A. Palazzo, M. Batka, M. Magalhaes, R. Valmonte-Santos, M. Ewing, and D. Lee. 2009. Climate change: impact on agriculture and costs of adaptation. International Food Policy Research Institute, Washington, DC, USA. https://doi.org/10.2499/0896295354

Nichols, R. 2018. Theft is property! The recursive logic of dispossession. Political Theory 46(1):3-28. https://doi.org/10.1177/0090591717701709

Nichols, R. 2020. Theft is property! Dispossession and critical theory. Duke University Press, Durham, North Carolina, USA.

Ohio Department of Natural Resources (ODNR). 2009. Ohio Drainage Manual. ODNR, Columbus, Ohio, USA. https://www.henrycountyengineer.com/wp-content/Policies/Ohio%20Drainage%20Laws%20&%20Petition%20Procedure.pdf

Osgood, R. 2000. Lake Sensitivity to Phosphorus Changes. Lake Line 20(3):9–11.

Ostrom, E., and C. Hess. 2010. Private and common property rights. Pages 53-106 in B. Bouckaert, editor. Property law and economics: encyclopedia of law and economics. Edward Elgar, Northhampton, Massachusetts, USA. https://www.researchgate.net/publication/257650634

Parkins, A. E. 1918. The Indians of the Great Lakes region and their environment. Geographical Review 6(6):504-512. https://doi.org/10.2307/207682

Richards, R. P., D. B. Baker, and D. Eckert. 2002. Trends in agriculture in the LEASEQ watersheds, 1975-1995. Journal of Environment Quality 31(1):17-24. https://doi.org/10.2134/jeq2002.1700

Rocha, J. C., G. Peterson, Ö. Bodin, and S. Levin. 2018. Cascading regime shifts within and across scales. Science 362(6421):1379-1383. https://doi.org/10.1126/science.aat7850

Rocha, J. C., G. D. Peterson, and R. Biggs. 2015. Regime shifts in the anthropocene: drivers, risks, and resilience. PLoS ONE 10(8):e0134639. https://doi.org/10.1371/journal.pone.0134639

Roy, E. D., J. F. Martin, E. G. Irwin, J. D. Conroy, and D. A. Culver. 2010. Transient social-ecological stability: the effects of invasive species and ecosystem restoration on nutrient management compromise in Lake Erie. Ecology and Society 15(1):20. http://www.ecologyandsociety.org/vol15/iss1/art20/

Sarker, A., H. Ross, and K. K. Shrestha. 2008. A common-pool resource approach for water quality management: an Australian case study. Ecological Economics 68(1-2):461-471. https://doi.org/10.1016/j.ecolecon.2008.05.001

Scavia, D., M. Kalcic, R. L. Muenich, J. Read, N. Aloysius, I. Bertani, C. Boles, R. Confesor, J. DePinto, M. Gildow, J. Martin, T. Redder, D. Robertson, S. Sowa, Y. C. Wang, and H. Yen. 2017. Multiple models guide strategies for agricultural nutrient reductions. Frontiers in Ecology and the Environment 15(3):126-132. https://doi.org/10.1002/fee.1472

Scavia, D., J. V. DePinto, and I. Bertani. 2016. A multi-model approach to evaluating target phosphorus loads for Lake Erie. Journal of Great Lakes Research 42(6):1139-1150. https://doi.org/10.1016/j.jglr.2016.09.007

Sekaluvu, L., L. Zhang, and M. Gitau. 2018. Evaluation of constraints to water quality improvements in the Western Lake Erie Basin. Journal of Environmental Management 205:85-98. https://doi.org/10.1016/j.jenvman.2017.09.063

Shapiro, J. S., 2018. The low but uncertain measured benefits of US water quality policy. PNAS 116(12):5262-5269. https://doi.org/https://doi.org/10.1073/pnas.1802870115

Slocum, C. E. 1905. History of the Maumee River basin from the earliest account to its organization into counties. Bowen & Slocum, Indianaoplis, Indiana, USA. https://www.loc.gov/item/05019553/

Smith, D. R., K. W. King, L. Johnson, W. Francesconi, P. Richards, D. Baker, and A. N. Sharpley. 2015. Surface runoff and tile drainage transport of phosphorus in the midwestern United States. Journal of Environment Quality 44(2):495-502. https://doi.org/10.2134/jeq2014.04.0176

Smith, D. R, K. W. King, and M. R. Williams. 2015. What is causing the harmful algal blooms in Lake Erie? Journal of Soil and Water Conservation 70(2):27A-29A. https://doi.org/10.2489/jswc.70.2.27A

Smith, D. R., M. L. Macrae, P. J. A. Kleinman, H. P. Jarvie, K. W. King, and R. B. Bryant. 2019. The latitudes, attitudes, and platitudes of watershed phosphorus management in North America. Journal of Environmental Quality 48(5):1176-1190. https://doi.org/10.2134/jeq2019.03.0136

Spiese, C. E., K. Rosster, A. Boise, M. Bowling, S. Moeller, A. Pinkney, E. Richards, N. Schalitz, and T. Street. 2018. Glyphosate as an underlying cause of increased dissolved reactive phosphorus loading in the western Lake Erie basin. American Geophysical Union, Fall Meeting 2018, abstract #B21A-08. https://ui.adsabs.harvard.edu/abs/2018AGUFM.B21A..08S/abstract

Staley, B. L. 2017. Harmful algal blooms: Ohio Senate Bill 1 and the challenge of agricultural regulation comments. Capital University Law Review 45:795-834. https://capitallawreview.scholasticahq.com/api/v1/articles/3822-harmful-algal-blooms-ohio-senate-bill-1-and-the-challenge-of-agricultural-regulation.pdf

Steffen, M. M., B. S. Belisle, S. B. f, G. L. Boyer, and S. W. Wilhelm. 2014. Status, causes and controls of cyanobacterial blooms in Lake Erie. Journal of Great Lakes Research 40(2):215-225. https://doi.org/10.1016/j.jglr.2013.12.012

Swetnam, T. W., C. D. Allen, and J. L. Betancourt. 1999. Applied historical ecology: using the past to manage for the future. Ecological Applications 9(4):1189-1206. https://doi.org/10.1890/1051-0761(1999)009[1189:AHEUTP]2.0.CO;2

Teter, J., S. Yeh, M. Khanna, and G. Berndes. 2018. Water impacts of U.S. biofuels: insights from an assessment combining economic and biophysical models. PLoS ONE 13(9):e0204298. https://doi.org/10.1371/journal.pone.0204298

U.S. Department of Agriculture (USDA). 2018. Recent trends in GE adoption. Economic Research Service, USDA, Washington, D.C., USA. https://www.ers.usda.gov/data-products/adoption-of-genetically-engineered-crops-in-the-us/recent-trends-in-ge-adoption.aspx

Vanderploeg, H. A., J. R. Liebig, W. W. Carmichael, M. A. Agy, T. H. Johengen, G. L. Fahnenstiel, and T. F. Nalepa. 2001. Zebra mussel (Dreissena polymorpha) selective filtration promoted toxic Microcystis blooms in Saginaw Bay (Lake Huron) and Lake Erie. Canadian Journal of Fisheries and Aquatic Sciences 58(6):1208-1221. https://doi.org/10.1139/f01-066

Vanderploeg, H., A. Wilson, T. Johengen, J. Bressie, O. Sarnelle, J. Liebig, S. Robinson, and G. Horst. 2013. Role of selective grazing by dreissenid mussels in promoting toxic microcystis blooms and other changes in phytoplankton composition in the Great Lakes. Pages 509-524 in T. F. Nalepa and D. W. Schloesser, editors. Quagga and zebra mussels. Second edition. CRC, Boca Raton, Florida, USA. https://doi.org/10.1201/b15437-40

Vollmer-Sanders, C., A. Allman, D. Busdeker, L. B. Moody, and W. G. Stanley. 2016. Building partnerships to scale up conservation: 4R Nutrient Stewardship Certification Program in the Lake Erie watershed. Journal of Great Lakes Research 42(6):1395-1402. https://doi.org/10.1016/j.jglr.2016.09.004

Vörösmarty, C. J., P. B. McIntyre, M. O. Gessner, D. Dudgeon, A. Prusevich, P. Green, S. Glidden, S. E. Bunn, C. A. Sullivan, C. R. Liermann, and P. M. Davies. 2010. Global threats to human water security and river biodiversity. Nature 467:555-561. https://doi.org/10.1038/nature09440

Walker, B. H., S. R. Carpenter, J. Rockstrom, A.-S. Crépin, and G. D. Peterson. 2012. Drivers, “slow” variables, “fast” variables, shocks, and resilience. Ecology and Society 17(3):30. https://doi.org/10.5751/ES-05063-170330

Walker, B., L. Gunderson, A. Kinzig, C. Folke, S. Carpenter, and L. Schultz. 2006. A handful of heuristics and some propositions for understanding resilience in social-ecological systems.Ecology and Society 11(1):13. http://www.ecologyandsociety.org/vol11/iss1/art13/

Watson, S. B., C. Miller, G. Arhonditsis, G. L. Boyer, W. Carmichael, M. N. Charlton, R. Confesor, D. C. Depew, T. O. Höök, S. A. Ludsin, G. Matisoff, S. P. McElmurry, M. W. Murray, R. P. Richards, Y. R. Rao, M. M. Steffen, S. W. Wilhelm. 2016. The re-eutrophication of Lake Erie: harmful algal blooms and hypoxia. Harmful Algae 56:44-66. https://doi.org/10.1016/j.hal.2016.04.010