Northeastern Research Station

Living Memorials

Research & Development

Hubbard Brook Experimental Forest

Introduction:

Hubbard Brook Experimental Forest (HBEF) was established in 1955 as a major center for hydrologic research in New England. Located in White Mountain National Forest in central New Hampshire, the 3,138-ha bowl-shaped Valley has hilly terrain, ranging from 222 to 1,015 m altitude. The Hubbard Brook Ecosystem Study was established by a cooperative agreement in 1963. In 1988 the HBEF was designated as a Long Term Ecological Research (LTER) site by the National Science Foundation.

Climate:

Annual precipitation averages about 1,400 mm, with one-third to one-quarter as snow. January averages about -9oC and the average July temperature is 18oC. The average number of days without killing frost is 145. The estimated annual evapotranspiration is about 500 mm.

Soils:

Predominantly well-drained Spodosols (Typic Haplorthods) derived from glacial till, with sandy loam textures. They are acidic (pH about 4.5 or less) and relatively infertile (base saturation of mineral soil ~ 10%). Soil depths, including unweathered till, average about 2.0 m surface to bedrock, although this is highly variable. Depth to the C horizon averages about 0.6 m. At various places in HBEF, the C horizon exists as an impermeable pan.

Vegetation Types:

The present second-growth forest is even-aged and composed of about 80 to 90% northern hardwoods and 10 to 20% spruce-fir.

Long-Term Data Bases:

Physical/Hydrologic Monitoring

• Instantaneous streamflow (9 stations)
• Daily precipitation (24 stations)
• Class A weather station data
• Weekly snow depth on snow courses
• Weekly soil temperature and moisture
  

Air Chemistry (SO2, HNO3, particulates, ozone)

Mirror Lake

• Instantaneous streamflow (3 inlets, outlet)
• Daily precipitation (2 stations)
• Weekly chemistry (3 inlets, outlet)
• Bi-monthly limnology (temp, chemistry, plankton)
  

Solution Chemistry

• Weekly bulk precipitation (6-10 stations)
• Monthly soil solution W5, W6
• Weekly stream at weirs of W1-9
• Monthly stream within W5, W6

Organisms

• Bird populations
• Phytophagous insect populations
• W2, W4, W5, W6 Vegetation, biomass, chemistry

Soils

• Forest floor mass, chemistry (W6, W5; 5-yr intervals)
• Chemical and physical properties from soil pits (W5)
• Chemical and physical properties from soil bags

Research - Past and Current: Experimental Watershed Manipulations:

Current:

• NSF - LTER and LTREB
• The role of calcium supply in regulating the structure and function of base-poor forest and aquatic ecosystems
• Animal population and community studies
• Colder soils in a warmer world: A snow manipulation in a northern hardwood forest ecosystem
• Stream Ecosystem Research
• A spatial model of soil parent material
• Modeling effects of acid deposition, forest disturbance and soil chemistry on forest production and stream water quality
• Use remote sensing for measurement of canopy nitrogen and calcium content, and estimation of forest production and stream chemistry
• Landscape-scale controls on N retention and N gas fluxes in the Hubbard Brook Valley
• Nutrient uptake at the Ecosystem Scale
• Carbon and calcium controls on microbial biomass and invertebrate grazers
• Does the small watershed chemical paradigm work throughout the entire HBEF valley? (Gene Likens, IES)
• The link between soils and plants: A 15N of plant available N
• Response of northern hardwood forests to nutrient perturbation
• Edaphic controls on the structure and function of the northern hardwood forest
• Vegetation dynamics and primary productivity
• Hubbard Brook Sandbox Studies

Major Research Accomplishments and Impacts on Management:

• Small watershed technique for studying biogeochemistry
• Factors regulating nutrient flux and cycling in northern hardwood forests
• First documentation of acid rain in North America
• Effects of forest harvesting disturbance on water quality and quantity
• Long-term effects of acid rain on soil nutrient pools and streamwater chemistry
• Relationship of interior forest bird populations and communities to forest structure and development
• Development and application of ecosystem process models: 1) hydrological, 2) forest growth and development, and 3) soil nutrient processes.

Collaborators:

Collaborators include researchers from other Forest Service research units, Institute of Ecosystem Studies, Brown Univ., Dartsmouth, Syracuse, Cornell, U. of Michigan, Yale Univ., Appalachian State, SUNY-ESF, USGS, Welleday College and the Smithsonian.

Research Opportunities:

We welcome new studies at HBEF and collaboration on existing ones. There is specific need for expanded cooperative research in the area of soil physics/forest hydrology.

Facilities:

The Robert S. Pierce Ecosystem Laboratory provides 835 m2 of space, including six offices, four laboratories, one conference room, six dormitory rooms, a kitchen, baths and showers; a sample archive building and 280 m2 of maintenance, storage, garage and shop facilities.

Contact Information:

Christopher Eagar
Northeastern Research Station
271 Mast Road
Durham, NH 03824
Phone: (603) 868-7636
FAX: (603) 868-7604
Email: ceagar@fs.fed.us
http://www.hubbardbrook.org
http://www.fs.fed.us/ne/durham/4352/hb.shtml

Location:

Hubbard Brook Experimental Forest is in the southern part of the White Mountain National Forest in central New Hampshire (43o56'N, 71o45'W; the geographic center of the HBEF). It lies in the towns of Ellsworth, Thornton, Warren and Woodstock, all in Grafton County, and is near the village of West Thornton.