managing nitrogen from cranberry bogs
DESCRIPTION
A presentation about managing nitrogen from cranberry bogs in the Buzzards Bay watershed, Massachusetts. Presented by Rachel Jakuba, Science Director for the Buzzards Bay Coalition, during the Buzzards Bay Coalition's 2013 Decision Makers Workshop series. Learn more at www.savebuzzardsbay.org/DecisionMakersTRANSCRIPT
Cranberry Agriculture in the Watershed – understanding N impacts
Rachel W Jakuba, PhDScience Director, Buzzards Bay Coalition
Agriculture in the Landscape
• Agriculture can be a significant contributor to N in coastal waters in SE MA, though wastewater is typically the largest source of N
• Cranberry is the dominant form of agriculture in the Buzzards Bay watershed
• While a low relative rate of fertilizer compared with other crops they are closely connected to waterways
Agriculture in the Landscape
• Agriculture can be a significant contributor to N in coastal waters in SE MA, though wastewater is typically the largest source of N
• Cranberry is the dominant form of agriculture in the Buzzards Bay watershed
• While a low relative rate of fertilizer compared with other crops they are closely connected to waterways
TMDLs will require N reductions
• Many coastal waters around Buzzards Bay are listed as impaired for N on 303(d) ‘Dirty Waters’ list
• MA is required to developed TMDLs for these waters that include plans for reducing N
• Massachusetts Estuaries Project develops a target N threshold that a specific estuary can handle and sources of N to that estuary
Distribution of N sources
• N reductions should be distributed across N sources, so it is important to understand the amount of N contributed from cranberry bogs
Agawam River subwatershed Wankinko River subwatershed
Data from Massachusetts Estuaries Project (Howes et al. 2013)
Challenges of managing N from bogs
• Variable process – N loss from cranberries bogs is influenced by management practices
• Limited quantitative information – only two scientific studies in SE MA on N loss from bogs
• Values from the two studies range by over 3-fold for N loading
Reducing Uncertainty
• Study to look at 2 common bog configurations• Partnership between Coalition, UMass Cranberry
Experiment Station, MBL, Town of Carver, Cape Cod Cranberry Growers’ Association
• Funded by DEP and BBNEPLong Tail Pathway Closed Loop
Basic study design
• Look at 3 examples of each bog type (i.e., 6 bogs total)
• Collect data for ~14 months• Measure N & P
concentrations in surface and groundwater before and after it reaches the bog
• Use water flow estimations to calculate the mass of nitrogen leaving the bogs
Basic study design
• Look at 3 examples of each bog type (i.e., 6 bogs total)
• Collect data for ~14 months• Measure N & P
concentrations in surface and groundwater before and after it reaches the bog
• Use water flow estimations to calculate the mass of nitrogen leaving the bogs
Study thus far
• QAPP outlining protocols approved by MA DEP and EPA
• Sampling began in late September with samples collected during the harvest floods
• Analysis of samples is underway• Groundwater appears to be a significant sink
of N
Questions?