Hubbard Brook Experimental Forest New

Fisher DW, Gambell AW, Likens GE, et al. 1968. Atmospheric contributions to water quality of streams in the Hubbard Brook Experimental Forest, New Hampshire. Water Resour Res 4 1115-1126. 

Figure 3 Long-term declines in sulfate concentrations mitigate the mobilization of aluminium in soil solutions and stream water in the Hubbard Brook Experimental Forest, New Hampshire, USAf a-c, annual volume-weighted concentrations of a, inorganic monomeric aluminium (Ah) b, organic monomeric aluminium (Af) and c, sulfate (SO/ ) in mineral soil solutions at 750 m (%) and 730 m (O), and in stream water (triangles)...

Johnson N. M., Driscoll C. T., Eaton J. S., Likens G. E., and McDowell W. H. (1981) Acid rain, dissolved aluminum and chemical weathering at the Hubbard Brook Experimental Forest, New Hampshire. Geochim. Cosmoshim. Acta 45, 1421-1437. 

Lawrence G. B., Fuller R. D., and Driscoll C. T. (1987) Release of aluminum following whole-tree harvesting at the hubbard brook experimental forest. New Hampshire, USA. J. Environ. Qual. 16, 383-390. 

Hall, R.J., Likens G.E., Fiance S. B. and Hendrey, G.R. Experimental acidification of a stream in the Hubbard Brook Experimental Forest, New Hampshire. Ecology 1980, 61, 976-989. 

Figure 3.3. Annual volume-weighted sulfate, nitrate, and ammonium concentrations and pH in bulk and wet deposition at the Hubbard Brook Experimental Forest, New Hampshire 1963-2000...

The input of airborne lead to the Forest ecosystems has been studied at the Hubbard Brook Experimental Forest in New Hampshire. The small catchment approach has been used to study the lead biogeochemical cycle since 1963 (Likens et al., 1977 Driscoll et al., 1994). By monitoring precipitation inputs and stream output from small watersheds that are essentially free of deep seepage, it is possible to constmct accurate lead mass balance. The detailed study of soil and soil solution chemistry and forest floor and vegetation dynamics supplemented the deposition monitoring. 

The study of SOM, and dissolved organic carbon (DOC) in soil solutions and stream samples in clear-cut and uncut sites at the Hubbard Brook Experimental Forest in New Hampshire using DOC fractionation techniques and solid-state C NMR has been presented. 

In the USA, two focal points for biogeochemical research have been the forest catchment ecosystems at Hubbard Brook Experimental forest in the White Mountains of New Hampshire and Coweeta Hydrologic Faboratory, located in the southern Appalachians of North Carolina. 

Biogeochemical cycles of individual elements, including nitrogen, have been intensively studied at the Hubbard Brook experimental Forest (HBEF) in New Hampshire, USA, since 1963, pioneering the use of the small catchment concept for understanding biogeochemical processes in the ecosystems (see Likens etal, 1977). The numerous... 

Fig. 8-11. Frequency distribution of pH values observed in hydrometeors. (A) Ernst (1938), 47 bulk rain samples collected in Bad Reinerz, combined with 80 samples showing a similar distribution collected in Oberschreiberhau (both locations in upper Silesia, central Europe), 1937-1938. (B) Mrose (1966), 206 bulk rain samples collected at Dresden-Wahnsdorf (German Democratic Republic), 1957-1964. (C) Esmen and Fergus (1976), about 200 individual rain drops collected during a single rainstorm in Delaware, 1974. (D, E) Likens etal. (1984), weekly samples of bulk rainwater collected at Hubbard Brook Experimental Forest Station, New Hampshire, D 1964-1968, E 1975-1979. (F) Falconer and Falconer (1980), 824 measurements of cloud water collected continuously at Whiteface Mountain, New York, 1977.

The Hubbard Brook Experimental Forest is a long-term ecological research site established by the U.S. Department of Agriculture Forest Service in the White Mountains of New Hampshire to investigate the structure and function of forest and aquatic ecosystems, and their response to disturbance (Likens and Bormann 1995 Groffman et al. 2004). Hubbard Brook was the site where acidic deposition was first reported in North America (Likens et al. 1972). Hubbard Brook receives elevated inputs of acidic deposition and the forest ecosystem is very sensitive to these inputs. There have been long-term measurements and studies of acidic deposition and its effects on forests and streams at Hubbard Brook (Likens et al. 1996 Driscoll et al. 2001). 

The longest-term experimental study of acid precipitation in the U.S. has been conducted at the U.S. Forest Service Hubbard Brook Experimental Forest in New Hampshire s White Mountains. It is downwind from major U.S. urban and industrial centers and is, therefore, a prime candidate to receive acid precipitation. This is reflected by mean annual pH values ranging from 4.0 to 4.2 during the 1964-74 period. During this period, the annual hydrogen ion input ([H" "] x volume) increased by 36%. 

Borman and Likens (1970) reported changes in the composition of water flowing from a watershed caused by removal of vegetation at the Brook Experimental Forest, Hubbard, New Hampshire (Fig. 16.3). 

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