Monteverde : Ecology and Conservation of a Tropical Cloud Forest

Table 2.2. Comparison of five precipitation events at two sites in the MCFP.

Weather Windspeeda
Conditions (m/s)

Stratocumulus cloud,
transition season
Event I
Windward
Leeward
Event 2
Windward
Leeward
Event 3
Windward
Leeward
Stratus cloud, dry season
Event 4 %
Windward
Leeward
Event 5
Windward
Leeward

5-10

2-4

10-15

2-5

15-20

4-6

5-10

2-5

10-15

3-6

Temperature^8

(°C)

12.7-17.0

13.0-19.6

14.5-17.2

14.9-17.6

12.5-17.1

13.6-18.0

15.9-20.0

15.9-22.1

15.6-17.7

15.6-21.1

Relative

Humidity^8

(%)

91-97

78-97

88-97

74-97

91-97

79-97

92-97

78-97

94-97

84-97

Precipitationb

(mm)

2.7C

2.7

2.5C

13.3

6.4C

16.1

trace

0.7

n.r.

3.7

Cloud Water +

Precipitation^15

(mm)

74.1

5.4

108.7

27.8

114.0

32.5

4.9

0.7

104.7

9.3

Data are cloud type, season, windspeed, ambient air temperature, relative humidity, and estimated cloud and precipitation deposition for
five precipitation events encompassing a range of environmental conditions at two sites in the preserve; a windward cloud forest site lo-
cated at La Ventana on the Brillante gap (1460 rn), and a leeward forest site approximately 1.5 km southwest of the preserve headquarters
(1480m),
aMinimum and maximum hourly means,
bTotal depth for the 24-hr period. Precipitation was sampled with standard rain gauges; cloud water & precipitation was sampled with a
cloud water collector (Clark 1994). n.r. = not recorded.
Precipitation depth undersampled due to high windspeeds.

EPIPHYTIC HISTOSOLS

Kenneth L Clark.& Natini M. Nadkarni

Ithough of limited distribution, epiphytic
Histosol "soils" are one of the most interest-
ing soils in Monteverde. They typically occur
on twigs, branches, and stems below epiphytes. The
largest accumulations of epiphytic Histosols occur in
forests that are exposed to wind-driven cloud water
and precipitation in the upper portions of Monte-
verde. They are derived from epiphytic vegetation, in-
cluding bryophytes (mosses and liverworts) and vas-
cular epiphytes (foliage, shoots, and roots), and from

host trees ("canopy roots" and bark; Nadkarni 1984,

Ingram and Nadkarni 1993, Clark et al. 1998a). In

contrast to the forest floor, host trees contribute rela-

tively little litterfall to these accumulations (Nadkarni

and Matelson 1991). Compared to mineral soils, epi-

phytic histosols typically have greater carbon and

nitrogen contents and lower pH, and are characterized

by lower rates of nitrogen mineralization (Vance and

Nadkarni 1990; Table 2.3),

Literature Cited

Alvarado, I. G. 1989. Los volcanes de Costa Rica. Editorial

Universidad Estatal a Distancia, San Jose, Costa Rica.

Asbury, C. E., W. H. McDowell, R. Trinidad-Pizarro, and S.

Barrios. 1994. Solute deposition from cloud water to the

canopy of a Puerto Rican montane forest. Atmospheric

Environment 28:1773-1780.

Baynton, H. W. 1968. The ecology of an elfin forest in Puerto

Rico. 2. The microclimate of Pico del Oeste. Journal of

the Arnold Arboretum 49:419-431.

Bergoeing, J. P., and L. G. Q. Brenes. 1977, Mapa geo-

34 The Physical Environment

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