Potatoes for Trout: Managing Agricultural and Aquatic Ecosystem Services in the Wisconsin Central Sands

EPA Grant Number: F13F11152
Title: Potatoes for Trout: Managing Agricultural and Aquatic Ecosystem Services in the Wisconsin Central Sands
Investigators: Nocco, Mallika Arudi
Institution: University of Wisconsin - Madison
EPA Project Officer: Jones, Brandon
Project Period: September 2, 2014 through September 2, 2016
Project Amount: $84,000
RFA: STAR Graduate Fellowships (2013) RFA Text |  Recipients Lists
Research Category: Academic Fellowships , Fellowship - Environmental Science

Objective:

The goal of this research is to determine how irrigated agriculture and climate affect surface water quantity and quality in response to scientific questions identified by stakeholders in the Wisconsin Central Sands. This work will produce coupled water-energy budgets under authentic agricultural management, which will be used to set parameters for and calibrate a regional agroecosystem-hydrological model. Model simulations will be driven with historical daily climate data to understand how cumulative changes in climate and land use have degraded surface waters over the past 60 years and to optimize future water management by contrasting low- and high-input scenarios.

Approach:

This research uses a transdisciplinary approach encompassing environmental biophysics, plant physiology and hydrology. Field experiments will take place on Isherwood Farm, a sixth-generation, 1500-hectare farm with 100 hectares of woodland and 7 kilometers of coldwater trout habitat located in the heart of the Wisconsin Central Sands. Potential recharge, soil moisture/temperature and water table depth will be monitored yearround using replicated passive capillary lysimeters, frequency-domain reflectometry probes and wells in six irrigated rotations of maize, potatoes and peas. During the growing season, measurements of crop phenology, porometry and remotely sensed infrared canopy temperature also will be collected. Air temperature and relative humidity will be measured both locally on Isherwood Farm and regionally across an east-west transect to test an irrigation-induced cooling hypothesis. These data will be synthesized into models of evapotranspiration and groundwater recharge to further understand agricultural perturbations to the water-energy cycle across diverse temporal and spatial scales.

Expected Results:

The Wisconsin Central Sands area has undergone both irrigation expansion and climate change over the past 60 years, which may have had either synergistic or antagonistic effects on the water-energy cycle. Surface waters in this region have been severely degraded over the past decade, with loss of both quantity and quality, leading to diminished aquatic ecosystem services. Hydrological models have estimated that groundwater pumping and irrigation may alter components of the water-energy budget on the same order of magnitude as climate change. It also has been demonstrated that intensive agricultural irrigation can modify regional climate patterns through evaporative cooling and increased cloud cover. Though it is well-established that groundwater pumping leads to aquifer depletion, this work will develop a more mechanistic model that links pumping, evapotranspiration, climate and aquatic interactions in shallow, glacial aquifers connected to surface waters, such as those found in Wisconsin, Minnesota and Michigan.

Potential to Further Environmental/Human Health Protection

Emergent philosophies of groundwater governance indicate that vertical integration, or a bottom-up social consensus, is critical to the success of any adaptive management plan. Central Sands farmers, conservationists and property owners have committed to understanding the land use processes that led to present aquatic conditions and implementing strategies to mitigate further damage to surface waters, while sustaining a viable agricultural economy. This project will engage key agricultural and aquatic stakeholders by integrating scientific results with local knowledge to identify remaining obstacles preventing adaptive management of surface waters.

Supplemental Keywords:

ecosystem services, irrigation, water-energy cycle