Monteverde : Ecology and Conservation of a Tropical Cloud Forest

Table 9.19. Elemental concentration, nitrogen to phosphorus

ratios, and nitrogen and phosphorus retranslocation of live

foliage and leaf litter in tropical montane forests (Nadkarni and

Matelson 1992a).

Site

Venezuelab

Live foliage

Leaf litter

Papua New Guinea^0

Live foliage

Leaf litter

Colombiad

Live foliage

Leaf litter

Costa Rica^6

Live foliage

Leaf litter

Elements

N

1.74

1.2

1.32

1.3

1.8

1.1

1.97

1.47

(%)

P

0.08

0.06

0.09

0.07

0.1

0.06

0.14

0.08

N:P

Ratio

22

20

15

19

18

18

18

Retranslocation^8

N (%)

31

2

38

25

P (%)

25

22

40

42

Calculated as % retranslocation = (element concentration in live foliage - litterfall)/

b(concentration in live foliage).

GFassbender and Grimm 1981.

dGrubb and Edwards 1982.

eVeneklaas 1991.

This chapter.

season. The relationship of litterfall to weather pat-
terns, which has been documented for other montane
forests (Tanner 1980a), awaits quantified measure-
ments of weather, especially windspeed and mist. The
amounts of nitrogen, phosphorus, calcium, and potas-
sium transferred in litter to the forest floor at Monte-
verde are high compared to those reported from other
tropical montane forests (Table 9.20). In Monteverde,

the large quantity of nutrient return in litterfall (despite

moderate retranslocation rates) is due to comparatively

high concentrations of nutrients (except Mg) in live tree

foliage (Grubb and Edwards 1982, Tanner 1985). The

foliar nutrient levels we measured in Monteverde

(Table 9.17) fall more closely within the range reported

for forests growing on alfisols and other moderately

fertile tropical soils (Vitousek and Sanford 1986).

Table 9.20. Forest litter data from various tropical locations.

Costa Rica

Venezuela

Jamaica
Mor ridge
Mull ridge
Wet slope
Puerto Rico

Colombia

New Guinea

Litter Fall

(tons/ha/yr)

7.0

7.0

6.6

5.5

5.5

*

11.6

7.6

N

93

69

39

94

34

*

*

90

Nutrient Transfer

(kg/ha/yr)

P Ca Mg

6 115 15

4 43 *

1.3 34 *

1.5 50 *

2.1 53 *

* * *

* * *

5 95 *

Forest

Floor

Standing

Crop

K (tons/ha)

12 10.1

* *

* *

* *

* *

5.1

* 16.5

* 6.4

Annual Biomas

Decay Element

Constant Ratio

(Ka)a N

0.69 75

101

169

* 112

* 162

0.94 *

0.61 *

1.17 84

P

1270

1750

5076

3666

2620

*

*

1520

Source

This chapter

Fassbender and

Grimm 1981

Tanner 1977

Wiegert and

Murphey 1970

Jenny et al. 1949

Edwards 1982

Data are fine litter production, nutrient transfer in litter, forest floor standing litter mass, annual decay constant (KJ, and biomass:element

ratio of fine litter in tropical montane forests, based on steady state assumptions. * = not reported.

aKa = annual litterfall/forest floor standing crop (Olson 1963).

331 Ecosystem Ecology and Forest Dynamics