Evaluating the impact of rivers on phosphorus delivery to western Lake Erie
Cyanobacteria blooms in WBLE have resulted in considerable ecological, cultural, and economic losses for the region1. It is now clear that the primary determinate of cyanobacteria blooms is P loading from the Maumee River watershed which is dominated by agricultural lands. While the impacts of various agricultural land-use practices on P exports from fields are beginning to be well understood, our understanding of the role of instream processes in shaping P loading to the lake is very limited. It is unknown whether rivers have a net positive, negative, or neutral impact on P loading to WBLE. This represents a critical knowledge gap because of timing, and the form of P export. Furthermore, riverine P cycles contribute to cyanobacteria blooms in rivers and could shape P delivery to WBLE in ways that diminish agricultural conservation efforts and enhance cyanobacteria blooms.
Here we propose to quantify the WBLE, to implement these processes into watershed models commonly used to inform management and to evaluate conservation scenarios in light of what we learn about instream processes. We will leverage considerable investments in monitoring and sampling by the USGS, U.S. Department of Agriculture Agricultural Research Service (USDA-ARS), and Heidelberg University National Center for Water Quality Research (NCWQR), enabling a robust analysis that uses multiple, complementary approaches to estimate the impact of instream processes on P export, which would otherwise be well outside the available funding. Our research will directly address Ohio Department of Natural Resources funding priorities related to the impact of instream processes on P delivery to WBLE. In addition, our watershed modeling leverages previous modeling efforts, including two modeling projects previously funded by HABRI, and will contribute understanding and better models towards Ohio Department of Agriculture priorities related to nutrient and water management.
For further details: Research – National Center for Water Quality Research (ncwqr.org)
Healthy Soils, Healthy Waters: Will Soil Health Improvements Mitigate Nutrient Loading To The Great Lakes?
The rationale for the project is that it will satisfy a pressing need to assess the efficacy of soil health practices within landscapes with fine-textured soils, such as the western Lake Erie basin (WLEB). The WLE
B (~17,000 km2) contributes a significant quantity of P from agricultural lands resulting in frequent and intense harmful algal blooms (HABs) in Lake Erie (Michalak et al. 2013, Scavia et al. 2014). Past efforts to reduce agricultural P losses in the WLEB and so mitigate the occurrence of Lake Erie HABs have largely concentrated on nutrient management practices such as P fertilizer rate, placement, and timing (Bruulsema et al. 2012, Vollmer-Sanders et al. 2016, Smith et al. 2018). However, despite efforts to promote the adoption of nutrient management practices the P loading problem has persisted (NOAA GERL 2019). Infield soil health practices are now being promoted with the expectation that they will help solve this persistent water quality issue while maintaining or improving crop productivity (Brandt and Shafer 2019). Hence, WLEB stakeholders have requested additional information regarding the efficacy of these practices within their landscape (see letters of support).
The significance of this project lies in the stakeholder need for a scientific basis for how soil health practices affect soil physical and biogeochemical processes. In addressing this need, our project will improve stakeholders’ capacity to effectively prescribe and adopt in-field
management strategies that mitigate downstream impacts, such as hypoxia and HABs. Further, our project will improve the capacity to represent and evaluate soil health practices within watershed-scale hydrologic models, which are commonly applied to inform stakeholder decision-making and policy development.
For further details: HEALTHY SOILS, HEALTHY WATERS: WILL SOIL HEALTH IMPROVEMENTS MITIGATE NUTRIENT LOADING TO THE GREAT LAKES? | National Agricultural Library (usda.gov)
Agricultural BMP handbook
The Kalcic Lab has been working on a collaborative project with Andy Ward and Greg LaBarge to create a best management practices (BMPs) handbook for farmers. This handbook would act as a field guide when farmer’s are looking to install effective BMPs.
People: Xioqiang Liu, Elizabeth Callow
Harmful Algal Bloom Research Initiative (HABRI):
Multi-model project aiming to quantify how the Great Lakes Water Quality Act Phosphorus reduction targets can be met in the Maumee River Watershed.
People: Anna Apostel, Haley Kujawa
Great Lakes Research Initiative: Effectiveness of phosphorus filters
People: Elizabeth Callow