Agroforestation of Grasslands in Southeast Asia: WaNuLCAS Model Scenarios for Shade-Based Imperata Control During Tree Establishment - Smallholder Tree Growing for Rural Development and Environmental Services - page 139

20

Measured
Simulated

40

18

35

16

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14

25

12

10 20

8

15

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a b

Year

Ye ar

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35

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13579 1 3 5 7 9 1357 9 1 3 5 7 9

c d

Year

Year

Fig. 6.3 Measured and simulated tree diameter of timber and non-timber trees (a) Eucalytus
deglupta ; (b) Gmelina arborea ; (c) Lansium domesticum ; and (d) Mangifera indica

There was a good agreement between the measured and simulated growth perform-
ance of three tree species ( E. deglupta, L. domesticum and M. indica ) as shown in
Fig. 6.3. It was only with Gmelina arborea that the simulated tree growth perform-
ance was much lower than the measured tree diameter.

6.3 Results

6.3.1 Results for the Indonesian Site

6.3.1.1 Tree Growth in Imperata Grassland at Different Weeding Intensities

The WaNulCAS simulations first of all corroborated a well-known fact: young trees
are not able to overcome competition with Imperata , unless their immediate sur-
rounding is kept weed-free. The 'partial weeding', i.e., the weeding of zone 1