UNH Organic Dairy Farm agroecosystem study

UNH Organic Dairy Farm agroecosystem study

Summary

Our original proposal outlined clear milestones for the first three years of this project. We are now in the middle of the third year, and have made significant progress against all of our goals. For example, at our agroecosystem site – the recently established UNH Organic Dairy Research Farm – we have:

– Produced a first outline of the nitrogen budget and cycle, and identified the major unknowns needing further work.

– Completed detailed studies on these poorly characterized parts of the cycle including
= Forage production and grazing intensity
= Hydrologic flowpaths and water chemistry

– Characterized energy requirements on the farm and investigated several alternative sources

– Investigated the productivity of woodlands on the Farm and the potential to use this resource for bedding, energy, and soil carbon enhancement

– Leveraged funds from the grant with substantial additional support from the NHAES and the College of Life Sciences and Agriculture

– Through this combined support, involved 5 graduate and 12 undergraduate students in original research projects on the Farm

– Presented the results of our work to a distinguished list of visitors, as well as UNH and pre-college students, and local farmers and community members

Objectives/Performance Targets

The following text is modified from the original proposal. An abstract of that proposal can be found on the website for the Organic Dairy Research Farm (http://www.colsa.unh.edu/aes/odrf/research/projects/SARE.html)
Dairy dominates animal agriculture in the Northeastern U.S., and is tied to the continuation of important cultural values including the conservation of open land and preservation of historical character. With the establishment of the first commercial-scale Organic Dairy Research Farm (ODRF) in the country, UNH is uniquely positioned to fulfill the traditional land-grant role of supporting a critical agriculture-based community in the state and region.

The purpose of this project is to use the ODRF as a test bed to achieve:
A Closed-System, Energy Independent Organic Dairy Farm for the Northeastern U.S.

We are pursuing a farm-ecosystem level approach to the measurement all of the material and energy flows occurring across the annual production cycle at the ODRF. Natural and human vectors are being compared, including, for example, inputs of nutrients in precipitation, feed and fertilizer, and losses in product shipment, surface water runoff and ground water leaching.

The work currently underway is seen as the first stage in a 9-year project that will use the data acquired in the first 3 years (phase 1) to redesign and implement changes in farm operations to decrease nutrient losses and fossil fuel requirements (phase 2), which will be refined and presented as best management practices (phase 3). The renewal proposal for the second round of funding has recently been submitted

Open communication and transparency have been an integral part of the UNH Organic Dairy Research Farm project from the beginning. UNH has established a set of stakeholder advisory groups which provide direct links and two-way communication between this research enterprise and potential users of the program’s outcomes. Emerging results of the research proposed here will be made available quickly and directly to the dairy industry. Some initial output products can be found at:
http://www.colsa.unh.edu/aes/odrf/research/projects/SARE/results

Performance:

As detailed below under Accomplishments and Milestones, we have made substantial progress against all of the goals specified for the first three years of the project.

Accomplishments/Milestones

Our original proposal outlined a project timeline for the first three years, as well as tentative goals for years 4-9. Thirty months into the project, we have made good progress against all milestones. These can be summarized using the list from the original proposal (Theses, posters and powerpoint presentations summarizing all results can be found at http://colsa.unh.edu/aes/odrf/research/projects/SARE/Results

Year 1: Finish outline of energy and nitrogen flows at the Organic Dairy Research Farm.
Basic studies on the energy and nitrogen cycles at the Farm have been completed. Energy usage is summarized as part of a detailed presentation on the potential for using the forest resource on the farm to meet both the bedding and energy needs of the facility, while also producing compost for application to the fields both to enrich soils and store carbon (powerpoint on website). A first approximation of the nitrogen cycle has been compiled from measurements made on the Farm, and from invoices and receipts for purchases and sales of feed, bedding, milk and animals. Results from this initial survey are presented in a poster that can also be accessed on the website given above.

Years 2-3:
• Conclude research into those flows which are most significant and least well quantified. These include:
o Water and nutrient flows to the Lamprey River
Measurements of the hydrological balance on the Farm were initiated in year 1 and have continued in Year 2. Increased precision has been achieved with the addition of 2 stream gages, 5 monitoring wells, and the acquisition and calibration of an in-situ soil moisture probe. Data are acquired at regularly scheduled intervals using both automated and manual methods.
Single well (slug) tests have been conducted on a number of wells to estimate the hydraulic conductivity of the different geologic materials. We have also completed a detailed mapping of the surficial geologic materials present at the farm and, along with information obtained from well drilling, developed a comprehensive conceptual model of groundwater and surface water flows at the site.
Our observations to date suggest that the farm shows a rapid response to individual precipitation events as water infiltrates through a relatively thin and permeable unsaturated zone and flows towards the lower elevations where it discharges through seeps and springs into a set of small streams discharging into the Lamprey River. Evapotranspiration is significant and diurnal fluctuations in both groundwater levels and streamflow are observed. These fluctuations will be used to help constrain estimates of evapotranspiration which, in turn, will help constrain our estimates of discharge from the farm. Groundwater withdrawals at the farm occur through a deep bedrock well and do not appear to significantly impact the natural shallow groundwater system through which the majority of the flows occur.
We have recently completed the synthesis of the geologic, topographic, and hydrologic information into a three-dimensional groundwater model using MODFLOW 2005 for a summer-fall season. We are utilizing the Unsaturated Zone Flow package which is enabling us to 1) simulate flow and storage in the unsaturated zone, and 2) account for surface water discharges that occur when the water table reaches the ground surface. A detailed water budget analysis suggests that the 84 acre watershed inclusive of the farm buildings and the majority of the main pasture (Field 2) is dominated by precipitation, evapotranspiration, and discharge into the wetland and small stream. Groundwater seepage rates out of the watershed appear to be small. The stream gauging instrumentation installed initially was destroyed during the two large floods in spring of 2010. We have upgraded the monitoring and are now positioned to obtain streamflows for the upcoming winter and spring.
The hydrologic flows are being combined with monthly sampling of groundwater wells and surface runoff in order to quantify nutrient exports. Results of the groundwater sampling show that levels of nitrate (NO3) are elevated in some wells down gradient of the agricultural operation, and can routinely exceed 10 mg/L NO3-N (Figure 2). Despite these high nitrate concentrations in groundwater, the surface creek draining the sites has moderate levels of NO3-N, typically below 1 mg/L. We have also sampled above and below the farm in the adjacent Lamprey River, and find no evidence of an impact of the ODRF on river water quality. Based on our chemical data and likely flow paths, it appears that passage of groundwater through a naturally vegetated wetland prior to entering the creek may play an important role in minimizing the impact of this contaminated groundwater on total N export from the site.
We will continue to monitor water levels, streamflow, and soil moisture, and will focus additional efforts on the wetland that appears to play a major role in reducing the impacts of dairy farm operations on water quality. Measured and modeled flow rates will be combined with water quality data to estimate mass fluxes. We will also begin the process of including solute transport processes into the modeling effort.

o Rate and composition of manure production as well as current storage practices and effects on decay and energy and nutrient balances

Manure production has been estimated as part of the nitrogen cycling work, based primarily on literature values. More precise estimates will be available from the pasture production and grazing work described below, and from volumetric estimates of material removed from barns.
In addition, we have begun examining alternative methods for manure management to produce energy while reducing greenhouse gas emissions and nutrient leaching to ground and surface waters. An undergraduate honors thesis has been completed that has measured the interactions among degree of aeration, and both pile temperature and CO2, CH4, O2 and H2S concentrations. Measurements have been made in large production piles at a major commercial farm operation, in operational piles at the ODRF, and in smaller experimental piles. Highly predictive relationships among the concentrations of these four gases are emerging which should quantify the benefit of either passive or active aeration for reducing greenhouse gas impacts of manure storage and composting. A poster summarizing some of the key results from this research is available at the website given at the top of this section. This poster was presented at the 2010 Undergraduate Research Conference. Of interest to the energy analyses described in Part II, the fans for this system were powered by a solar collector/battery energy source.
As described below (Impacts and Contributions), the research around manure handling and composting has affected the design of a newly constructed barn at the Farm, as well as current planning for a new manure storage facility that will be designed to produce energy while minimizing nutrient leaching and trace gas emissions.

o Productivity of pasture and woodland systems
Productivity of the woodlands included in the ODRF site has been measured and results have been posted to the projects webpage. It is estimated that the nearly 160 acres of woodlands on the farm can produce enough wood on a sustainable basis to meet total farm demand for both bedding and energy. This work was carried out with the help of a number of undergraduates who were introduced to field research through this project. A powerpoint file summarizing the results is available at our results website given above. It is not unusual for operating farms in New England to have similar forest resources. The historical pattern of land clearance until the mid-nineteenth century, followed by land abandonment and forest regrowth over the last 150 years has resulted in a mix of open and forested land in most areas in which agriculture is still active.
Alternative ways for utilizing the energy resource represented by this forest resource are presented in the next section.
In compiling the initial nitrogen cycle data reported above, it became apparent that better estimates of pasture productivity, grazing, and in-field manure production are essential. We are currently working with a Masters student on a detailed study of each of these parameters. The work so far has included a comparison of 4 different methods for rapid and accurate estimation of pasture biomass. Using the selected method, sequential measures of biomass before and after grazing, and during the regrowth period between grazing events, has been shown to yield consistent and very interesting information on the factors affecting grazing intensity and pasture production between grazing events. A key finding has been that pastures were overgrazed in the summer of 2009 (reduced to too little plant mass following grazing) and this has been used to redefine paddock size in 2010.

• Investigate alternative methods for increased efficiency of resource use, generation of energy and minimization of nutrient loss.
A number of alternatives for energy production on the farm have been identified. Exploration of the potential for wind, solar, increased efficiency, geothermal and other approaches have made perfect student project topics. Of these, two were shown to have significant potential.
The first is geothermal. Initial contacts have been made with a geothermal energy company and preliminary designs produced for general heating and cooling of milk tanks using this resource (see results website). Milk cooling seems to be the best first avenue for exploration, as described in the section on proposed work below.
The second is wood energy. Analyses have compared the use of wood directly in a conventional thermal system, or in a cogeneration plant that yields both heat and electricity. Cogeneration plants are not yet available at the size needed for the Farm, but investigations into that possibility will continue. The use of wood for bedding, energy and as a soil amendment has been discussed above and is summarized in a presentation on the website.
We have tested two different methods for producing shavings suitable for bedding either from wood chips, or directly from whole logs. In the following section on proposed work we outline steps to be taken to test this method for producing bedding, and the applicability of an integrated wood-bedding-compost system for producing both energy and soil amendments.

• Analyze economic impact of alternative systems
o Reduction in energy costs
o Increase in sales of products (e.g. organic compost and milk products)
These two topics will be addressed in the third year of the project, once the information on the full set of energy alternatives, and the potential for direct marketing and on-farm processing have been fully explored.
Close cooperation between this research project and the operation of the organic dairy, along with significant contributions by a major organic processor (Stonyfield Farms) have resulted in significant changes in farm infrastructure and overall farm management practices. These changes provide excellent opportunities for documenting the effects of alternative management methods on energy and nutrient cycles.

Impacts and Contributions/Outcomes

Impacts of the work reported here include
1. Visits to the Farm by stakeholders both individually and as part of organized outreach functions
2. Changes in direction for support for research, facilities design and construction, and Farm operations by the New Hampshire Agricultural Experiment Station (NHAES)
3. Students trained and traditional scientific presentations

Transparent and open communication has been a goal of this project, and of the Organic Dairy Research Farm since its inception. Diverse groups of stakeholders have visited the farm over the last 2 years, and each group learns about the SARE Agroecosystem study underway here. The College of Life Sciences and Agriculture at UNH, as well as the NH Agricultural Experiment Station (NHAES) have been generous with matching support, and have used the goals and early results of this project to design facilities and alter management processes. That support has also multiplied the number of students engaged in the project to date. The outcome of faculty and graduate student research has been captured in a number of masters theses, and is being prepared for publication.

1. List of recent visitors to the Farm include:
• Approximately 40 Agricultural Attaches arrange by Deputy Secretary of Agriculture Dr. Kathleen Merrigan
• Top management personnel from Stonyfield Farms, Horizon Organic Dairy, Aurora Organic Dairy and Organic Valley, attended also by Lorraine Merrill, State Commissioner of Agriculture.
• UNH Alumni Association (Site visit for annual meeting)
• Students in UNH classes, including:
o Dairy Management I and II
o “The Real Dirt”
o Introduction to Horticulture
o Forages
o Ecogastronomy
o Water – How Much is Enough?
o Principles of Hydrology
• Students from pre K-12 schools, including
o Oyster River Preschool/Parents
o Phillips Exeter Academy
o Dairy Travel Course
• About 50 people from UNH and surrounding communities, including NH Secretary of Agriculture Lorraine Merrill, who attended the first Burley Demeritt/Organic Diary Field Day in August 2010
• A number of local farmers, visiting Faculty, and community members who are always welcome at the Farm.

2. Contributions from NHAES and Impacts of this Research on Operations
The NHAES is providing considerable funding to leverage this project. In round numbers, these include:
• $28,000 annually to support the 12-month cost for a graduate student
• $11,000 to cover tuition for another graduate student whose stipend is paid by SARE
• $7,000 for half-time support for a third graduate student to compile historical cropping and related information
• $5,000 to undertake water quality monitoring in the adjacent Lamprey River
• $21,000 of Dr. McDowell’s salary for work on this project
• $200,000 per year (net of milk revenues), to cover the operations of the farm, which are managed in close cooperation with the SARE project in terms of goals and objectives. This includes a full-time on-site manager with considerable farm operations experience and a background in cooperative extension work supports the outreach components of the project.

In addition, the new direction in experimental management for the Farm established as part of the SARE project has resulted in significant changes in facilities design.

• The newly (2009) constructed barn which houses stock in the winter was constructed as a bedded pack facility in cooperation with the composting and nutrient management goals of the SARE project. It also includes runoff reduction and sediment retention that should reduce N inputs to groundwater.
• Plans for a manure handling facility are going forward with the goal of incorporating information gained from the composting research objective of this project.

NHAES is also supporting a number of related studies focusing on animal nutrition and health, including:
• Tom Foxall, Pete Erickson, Nancy Whitehouse and Colleen Chapman (graduate student) will be starting a study titled “Markers of Health Status in Pasture-Fed vs. Total Mixed Ration-Fed Dairy Cows”.
• André Brito and Lindsay Chase (undergraduate-Animal Science Pre-Vet, Senior Honor’s Thesis) will be conducting a study titled “Effect of Kelp on Growth of Dairy Calves” to start shortly.
• In addition, Professor Brito has, with initial support from NHAES, submitted two grant proposals: 1) To Organic Farming Research Foundation (OFRF), titled “Molasses as an Alternative Energy Feed Source for Organic Dairies”, and 2) “Can sunset pasture allocation and low concentrate supplementation optimize milk production?”

3. Graduate and Undergraduate Student Support
The combination of SARE funding and the collaborative support from the NHAES described above has supported a number of undergraduate and graduate students who have made significant contributions to the project, and represent a first generation of new professional trained at UNH in the agroecosystem area.
The following Masters students have completed or are nearing completion of their thesis work (with thesis titles and date of completion):

• Jennifer Campbell (SARE) – Earth Science – Spatial and temporal groundwater recharge patterns in a temperate climate: An investigation at the Burley Demeritt Farm, Lee, New Hampshire – May 2010.
• Catherine Dunlap (SARE/NHAES) – Natural Resources and the Environment – Seasonal nitrate dynamics in an agriculturally influenced New Hampshire headwater stream – May 2010
• Michelle Galvin (SARE) – Natural Resources and the Environment – Hydrologic and nutrient dynamics in an agriculturally influenced New England floodplain – May 2010
• Ashley Green (NHAES/SARE) – Natural Resources and the Environment – Investigating optimal methods for measuring pasture productivity and grazing intensity under intensive rotational management – Degree expected December 2010.

It is anticipated that each thesis will result in a published paper.

In addition Dr. Davis will be presenting a paper at this year’s meeting of the American Geophysical Union (AGU) on “Hydrological and biogeochemical investigation of an agricultural watershed, southeast New Hampshire, USA” authored by JM Davis, WH McDowell, JE Campbell, and AN Hristov.
The SARE project has provided an excellent platform for a number of significant undergraduate research projects. Two undergraduate honors theses were completed in May 2010:

• Gabriel Perkins – Environmental Sciences – Assessing Avenues for Sustainability: Evaluating Nitrogen Flows at UNH’s Organic Dairy Research Farm

• Amy Lamb – Environmental Sciences – Composting and Sustainability: Trace Gas Yields and Energy Production with Different Materials and Methods

In addition, the following undergraduates have been engaged in research projects relating to history of land use on the farm, potential alternative sources of energy, and measurement of groundwater dynamics:

Jacqueline Amante, class of 2012
Makenzie Benander, class of 2012
Helen Clark, class of 2010
Brian Godbois, class of 2010
Paul Pellissier, class of 2012
Isabella Oleksy, class of 2012
Cathleen Turner, class of 2013
Bryan Vangel, class of 2012

All of these undergraduates have presented their finding at the UNH Undergraduate Research Conference, and some of their posters can be found on the ODRF webpage.

Collaborators: