LCZO -- Overland Water Chemistry, Nutrient Fluxes, Rainfall Chemistry, Throughfall Chemistry -- Includes Weekly Rainfall flux -- Bisley -- (1988-2002)

OVERVIEW

Description/Abstract

Changes in the quantity and quality of precipitation as it passes through vegetative cover are important components of both hydrologic and nutrient budgets.

Throughfall over any period depends on the balance between precipitation, evaporation and canopy storage (Horton, 1919; Leonard, 1967; Rutter et al., 1972). If the watershed is divided into different vegetation types based on similarity in throughfall and steamflow, the total throughfall over the watershed can be expressed as:

(1) Pg = Sum( T n A n )+ Sum (Sm Dm)

Where Pg = total throughfall reaching the ground, Tn = canopy throughfall from vegetation type n, An = area of vegetation type n, Sm = stemflow from stem type m and Dm = number of stems in type m.

Using eqn. (1) to estimate total watershed throughfall becomes a problem of determining the minimum number of vegetation types necessary to describe the system at the required level of accuracy. In one of our studies, measured throughfall was compared with actual canopy and stem conditions to estimate the percentages of throughfall for different time periods was calculated by weighting the average throughfall and stemflow measured in representative areas of each vegetation type by the total area of that vegetation group.

Measurements reported here were made in two of the Bisley Research Watershed of the U.S. Forest Service. These adjacent watersheds drain 13.0 ha of highly dissected mountainous terrain that range in elevation from 265 to 455 m. Both watersheds are covered by Tabonuco type forests and were selectively logged at various times between 1860 and 1940 (Scatena, 1988). The dominant tree in the watersheds in the Tabonuco ( Dacryodes excelsa ) which often comprises as much as 35% of the canopy ( Wadsworth, 1970). Structurally the forest has three dominant layers, a discontinuous emergent strata, a continuous upper stratum at 20 m, and an understory layer. Leaves are mesophyllous and often covered with epiphytic growth.

Creator/Author

Scatena, F.N.|IITF|Heartsil-Scalley

CZOs

Luquillo

Contact

Miguel Leon, Miguel.Leon@unh.edu

Subtitle

Nutrient fluxes for rainfall and throughfall in the Bisley watersheds; Bisley Weekly Rainfall flux

SUBJECTS

Disciplines

Water Chemistry

Topics

Overland Water Chemistry|Nutrient Fluxes|Rainfall Chemistry|Throughfall Chemistry

Subtopic

Includes Weekly Rainfall flux

Keywords

Hydrology|Water Chemistry

Variables

Throughfall Precipitation mm/day|pH|Conductivity|PO4-P|NH4-N|Na|K|Mg|Ca|Cl|NO3|SO4-S|SiO2|TD| For more details please see:

Variables ODM2

Calcium|Chloride|Electrical conductivity|Potassium, dissolved|Magnesium, dissolved|Sodium, dissolved|Nitrogen, NH4|Nitrogen, nitrate (NO3)|pH|Phosphorus, phosphate (PO4)|Silica|Sulfate, dissolved|Nitrogen, total dissolved|Precipitation

TEMPORAL

Date Start

1988-03-08

Date End

2002-12-31

SPATIAL

Field Areas

Bisley

Location

Bisley

North latitude

18.314405999999998

South latitude

18.314405999999998

West longitude

-65.74491

East longitude

-65.74491

REFERENCE

Citation

Scatena, F.N., IITF, Heartsil-Scalley, IITF. Bisley weekly throughfall flux. 2013.

CZO ID

2626