Current Projects

 

LINKING WET DEPOSITION TO AIR MASS CHEMISTRY

Wet deposition (WD) samples have been collected at the Thompson Farm atmospheric observatory in coastal New Hampshire in conjunction with the AIRMAP program since November 2003.  Samples are analyzed for DOC, TDN, DON, NO3, NH4, PO4, Cl, SO4, Oxalate, Na, K, Mg, Ca, SiO2, pH and specific conductance.  DOC and Cl are the dominant constituents in wet deposition and inorganic nitrogen species dominate wet N deposition.  Constituents in wet deposition have been compared to various metrics of average daily atmospheric chemistry (AC) occurring on the day of the wet deposition event using canonical correlation analysis (CCA) to infer sources of wet deposition.  Atmospheric chemistry metrics included continuous measures of air quality, aerosols and various volatile organic carbon (VOC) compounds.  Three WD canonical variates (CVs) were significantly related (p<0.05) to three AC CVs and together could explain 62% of the variation in WD constituents.  The AC CV loaded with VOCs mostly of biogenic origin was related to the WD CV loaded with DOC, TDN and NH4.  The AC CV loaded with parameters representing urban or 2° processed air was related to the second WD CV loaded with TDN, NH4, NO3 and SO4.  The AC CV representing a mixture of ocean, urban and biogenic sources was related to the third WD CV loaded with Na and Cl.  Our results suggest that interaction with urban/processed air masses drives temporal variation in wet deposition of most solutes, but DOC deposition is driven more by biogenic sources.

McDowell, W.H.,  Daley, M.L., Sive, B.C. and Talbot, R. 
For more information contact: Bill McDowell or Michelle Daley

 

UNDERSTANDING SPATIAL AND TEMPORAL DIFFERENCES IN N2O WITHIN THE LAMPREY RIVER WATERSHED

The overall goal of this project is to understand spatial and temporal patterns in dissolved N2O dynamics in the Lamprey River Watershed.  Secondary goals include developing an understanding of controls on the end products of denitrification and relating these controls to field conditions.

For more information contact: Emily Difranco

 

THROUGHFALL CHEMISTRY IN A DECIDUOUS AND CONIFEROUS FOREST STAND

The purpose of this project is to compare the chemical composition of thoughfall in a deciduous and coniferous forest stand at the Thompson Farm AIRMAP site in Durham, NH.  Temporal variability in throughfall chemistry will be compared to the temporal variability in wet deposition and in air mass chemistry.  Air mass chemistry may drive variation in throughfall chemistry directly through dry deposition on leaf surfaces or indirectly by influencing wet deposition chemistry or tree health.  Wet deposition volume will also be compared to throughfall volume in the two forest types and rates of wet deposition and throughfall deposition will be determined for organic matter, nutrients and major anions and cations.
 
For more information contact: Musa DINC

 

AFFECTS OF A FROST HORIZON ON GROUNDWATER RECHARGE IN A STRATIFIED DRIFT AQUIFER

The importance of meteorological conditions on the presence and extent of afrozen soil horizon is widely recognized in the literature (e.g. Flerchinger et al., 1992 and Stahli et al, 1999, Hayashi et al., 2003). In addition, there is an increasing recognition that frozen soil conditions are important factors in understanding hydrologic and biogeochemical processes in northern New England (Groffman et al., 1999; Hardy et al., 2001; and Decker et al., 2003).

Stratified drift materials represent important groundwater storage reservoirs throughout New England river valleys. One important source of recharge to these deposits is the direct infiltration of snowmelt and precipitation. Because the constructional delta deposits of the Burley-Demeritt Farm (UNH property in Lee, NH) are modern topographic highs, the only recharge is due to infiltration making this an ideal location for investigating infiltration recharge.

We hypothesize that the amount of snow cover will be a dominant factor indetermining the presence and vertical extent of a frost zone. The presence and extent of a frost zone will in turn affect the efficiency with which spring snowmelt and precipitation recharge the aquifer. We also hypothesize that the recharge will be sensitive to the timing of the snowmelt relative the ground thaw and spring rain events. By compiling multi-year records of daily soil temperature, soil moisture, groundwater level, air temperature, precipitation, and weekly measurements of snow moisture content, we will be able to quantify the hydrometeorological factors affecting recharge in the stratified drift deposits of Lamprey River Watershed.

Site characterization will include construction of a detail base map (including topography and surficial geology), a suite of surface geophysical measurements to map the depth the bedrock (magnetometer and seismic) and the stratigraphic features (GPR) of the sand-and-gravel deposits.

Monitoring will include soil temperature, soil moisture, air temperature, precipitation, snow depth and snow density, and water table elevation. We will most likely employ the commonly used technique of time-domain reflectometry (TDR) to monitor soil moisture along two vertical profiles. However, this is an invasive technique that disturbs the soil in the vicinity of the measurements introducing some error (Roth et al., 1997). We will also explore the feasibility of using electrical resistivity as a non-invasive technique for monitoring soil moisture (Zhou et al. 2002, 2003). One potential advantage of using electrical resistivity is that similar studies could be conducted a larger spatial scales.

Understanding the hydrometeorological factors affecting recharge is a critical component in developing best management practices for water resource and land use as well as understanding the potential impact of climate change on the hydrologic conditions in New England. While individual instrumented plots that monitor hydrologic and meteorological conditions are essential to understanding the processes controlling recharge, these plots will not provide sufficient information about integrated flow rates and pathways. Therefore, we will also plan to explore (stable) isotopic methods of tracking individual pulses of water through the system.

Davis, Jacobs, Clennon and Eller.
For more information contact: Matt Davis

 

HYDROLOGIC CONDITIONS ALONG THE NORTH RIVER

To improve our understanding of groundwater stores and flowpaths in the Lamprey River watershed we will conduct a detailed analysis of the hydrologic conditions along the North River. The North River originates at North River Pond in Barrington, flows through a significant marine sand deposit in Nottingham, and then through till-covered bedrock in Lee before reaching the Lamprey River near the intersection of US125 and NH155.

We hypothesize that the different hydrogeologic conditions (marine sand and till-covered bedrock) along the North River are significant controls on the groundwater flow rates and groundwater residence time in the sub-basin. We will test this hypothesis initially by monitoring baseflow conditions along the North River during late summer and early fall using a series of three stream gages and at least one monitoring well.

Continuous (though not real time) water levels will be obtained using ultrasonic distance sensors (e.g. Sontek) and data loggers (e.g. Hobo) to gage the flow in the North River at bridges on McCrillis and Freeman Hall Roads, Nottingham, NH. (We have obtained verbal permission from the Town of Nottingham to install sensors at these bridge locations.) Rating curves will be constructed based on manual stream gaging for a range of flow conditions at both stations. Groundwater levels will also be monitored in the Nottingham marine sand deposit. We are also working with the NHGS to identify monitoring wells (or locations for new wells).

The North River Study will be supported by and complement other recent and ongoing activities in the area. The most recent maps of the surficial geology in the Epping and Barrington 7.5 Minute Quadrangles (Goldsmith 1990a, 1990b) are in the final stages of being digitized and will provide important high-resolution coverages for the North River Study. The USGS has recently installed a continuous (real-time) gaging station on the North River that will complement our two gaging stations. The hydrologic analysis of the North River will also complement the ongoing water quality research on the North River (Proto and others).

Davis, Jacobs, Clennon, Proto.
For more information contact: Matt Davis

 

BEDROCK AQUIFER FLOWPATHS

Delineation of groundwater flowpaths in fractured rock environments is plagued by the difficulties of obtaining sufficient data at an appropriate scale to successfully apply continuum models (e.g. Darcy's Law) that rely on hydraulic head and hydraulic conductivity to predict flow paths and flow rates. Isotopic tracers are well-established tools for studying the movement of water from the surface into groundwater systems. Although first applied several decades ago (e.g., Stueber et al., 1975; Collerson et al., 1988), radiogenic isotopic tracers, such as 87Sr/86Sr, have recently re-emerged as a potentially powerful tool for studying reactive processes during infiltration ( Johnson and DePaolo, 1997a; Maher et al., 2003; Hogan and Blum, 2003), as well as timescales and flow pathways of water movement (e.g., Johnson and DePaolo, 1997b; Johnson et al., 2000). These types of studies are especially useful, when coupled with trace elemental analyses (e.g., Bau et al., 2004), for quantifying these processes and placing constraints on reactions occurring in the groundwater system.

We propose to use radiogenic isotopes (87Sr/86Sr and 143Nd/144Nd) coupled with trace elements to identify flow paths in the Lamprey River watershed. Our study will potentially provide insights into the identification of recharge areas, residence times of groundwater in these areas, and fate of metals in groundwater systems (e.g., Fee et al., 1992). We will conduct a pilot project on waters hosted by the White Mountain Plutonic Series (K9AB and K7C - Click to see figure). We have selected a site where we anticipate there to be isotopic contrast in the bedrock, based on known isotopic compositions of the igneous and metamorphic hosts (Eby et al., 1992). Preliminary results from water samples collected during Spring 2004 confirm the distinct isotopic signatures in the surface waters occurring in the Massabesic Gneiss Complex (Zmz) and the White Mountain Plutonic Series.

Our study will consist of samples of the aquifer via analyses of waters from both the lakes and nearby wells. We will also perform leaching experiments on the bedrock, soils and sediments in each area so that we may (1) improve our quantitative understanding of the chemical consequences of mineral dissolution reactions occurring during the infiltration process and (2) therefore effectively capture the isotopic and trace element signal that is contributed in this region.

Our initial sampling will include approximately 20 water samples from lakes and wells, 15 'rock' samples including bedrock, alluvium, and lake sediments, and 15 samples from leaching experiments. The samples will be prepared in the Earth Sciences Geochemistry Lab and the isotopic and trace element work will be conducted off site (e.g. WHOI).

Bryce, Davis and Smith.
For more information contact: Julie Bryce

 

IMPACT OF STREAM PIPING ON ECOSYSTEM PROCESSES

Piped streams may constitute a significant portion of urban streams, and the number of piped streams may increase with augmenting development.  Nutrient cycling and ecosystem metabolism should be altered drastically in piped streams.  However, the literature contains very few studies that measure ecosystem processes within pipes.  The objective of this study is to characterize ecosystem processes, including nitrogen cycling and ecosystem metabolism, within a piped stream (Pettee Brook, Durham, NH). Additionally, sites upstream and downstream of the piped stream section will be assessed to measure changes in ecosystem function due to the pipe.  This investigation addresses the apparent lack of empirical research to support the theory that piped streams suffer from complete degradation of ecosystem services such as nutrient retention and removal.  Direct evidence regarding the impacts of stream burial on ecosystem services may support decision-makers’ efforts to reverse the trend of increasing stream burial accompanying urbanization.  Furthermore, an increased understanding of processes within piped streams may offer insight into restoration attempts such as daylighting.  Finally, this study may add to our understanding of stream ecological processes. 

For more information contact: Amanda Hope

 

ORGANIC DAIRY

Sustainability advances the integrity of interactions between society and ecosystems that enhance the quality of life.  The University of New Hampshire’s university-wide program in sustainability, established in 1997, is organized around the interactions of climate, biodiversity, food and culture systems and the need to sustain the integrity all four simultaneously.  Enhancing the long-term viability of farming practices that provide off-farm values such as environmental quality, and support dynamic local communities, is integral toUNH’s commitment to sustainability. 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 Research Dairy Farm 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 vision for the project begun with this proposal is to use the newly established, commercial-scale, operating Organic Dairy Research Farm (ODRF) at the University if New Hampshire as a test bed to achieve the vision of this project:

A Closed-System, Energy Independent Organic Dairy Farm for the Northeastern U.S. We propose a farm-ecosystem level approach to the measurement all of the material and energy flows occurring across the annual production cycle at the UNH Organic Dairy Farm.  Natural and human vectors will be 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 proposed work 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).

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.

Web link: http://colsa.unh.edu/nhaes/odrf
For more information contact: John Aber

 

Ecosystem Services in Fragmenting Landscape

Characterizing human impacts on ecosystem services encompasses several of the Grand Challenges in Environmental Sciences (NRC 2001). In New Hampshire, as in much of New England, forests provide some of the most important ecosystem services, including clean water, fuel, fiber, essential habitat, carbon sequestration, and vital economic opportunities for tourism and recreation. Southeastern NH is undergoing rapid land use change due to its rapidly increasing human population density, and forest parcels are becoming smaller and more fragmented. This project will examine the impacts of these three aspects of development – land use change, parcelization, and forest fragmentation- on a suite of ecosystem services. Although our initial efforts will produce valuable short-term products, our research initiative will also include development of a long-term research infrastructure that will document the trajectory of change in our study region and provide insights into the tradeoffs in ecosystem services that accompany various development strategies.

Our specific long-term goals are to:

  1. Document historic and ongoing patterns of population density, land use, land cover, and forest fragmentation in the watershed
  2. Assess standing stocks of C and N in soils, dead wood (coarse woody debris), and tree biomass in plots with different land uses and document ongoing changes due to forest fragmentation
  3. Quantify impacts of land use change and forest fragmentation on abundance and diversity of soil microflora and amphibians
  4. Document impacts of past and ongoing land use change and forest fragmentation on water quality and stream invertebrates
  5. Develop a public education campaign to inform New Hampshire residents of the goods and services that local ecosystems provide, with an emphasis on the Lamprey River watershed

McDowell, W. H.; Babbitt, K. J.; Congalton, R. G.; Ducey, M. J.; Frey, S. D.; Kovach, A. I. 
For more information contact: Bill McDowell