WBC-VIII-Vol.4 – Resources – Forestry, Plantations and ... - BambuSC

were weighted at depth of 50 cm. Thereafter, the Kruskall Wallis test was performed for comparing the
capability of soil for water storing and resistance to erosion among the different land uses and land covers
Comparisons of soils properties among different land use and cover evidenced values of CWS (water regulation)
of 530 m 3 ha -1 . The higher value, although statistically not significant was for covers of forest with 572 m 3 ha -1 .
Whereas the lower value was found under crops and pasture (Figure 13). The similar values of CWS obtained
are explained because soils in the coffee region are highly homogeneous. Most of them are Andisols originated
from volcanic ash; consequently have special physical properties as low bulk density and high effective depth
(Malagon et al. 1995). While soil properties as those above mentioned do not change strongly, values of CWS
will tend to be similar among covers. Previously, Sadeghian et al. (2001) found lower values of bulk density and
soil compacting under guadua stands than those simplified land cover as crops and pastures. In this study it was
evidenced that low values of bulk density and soil compaction contributed to a better balance between water and
air within soils. It is important to remark that covers of forest and guadua forest are usually located in marginal
areas where agriculture and cattle are not feasible. It means that natural soil conditions for these areas are
limited by factors as slope and effective depth. Nevertheless, the value of CWS was higher under forest and
similar to the other covers under guadua forest. It shows that even on limited soils, forest cover (guadua
included) can maintain proper physical characteristics or improve them.
m 3 ha -1
700
600
500
400
300
200
100
0
Forest Guadua
Forest
Mixed crops Silvopastoral
System
Crops Pasture
Figure 13. Capability of water storing in soils under different land use and land cover. La
Vieja, watershed river. Vertical lines on the bars indicate the standard deviation.
The resistance to erosion showed significant (P