Page 121 - Ilmu Tanah

108 The Chemistry and Fertility of Soils under Tropical Weeds

correlated with all investigated soil enzymes in the cassava fields (r = 0.545* -
0.934**), with the activities of acid and alkaline phosphatases in the sugarcane
fields (r = 0.455* and 0.837**, respectively), and with that of acid phosphatase in
the pineapple fields (r = 0.481*). Salam et al. (1998b) also previously report that
the activities of some soil enzymes (acid phosphatase, alkaline phosphatase, -
glucosidase, and urease) in West Lampung, Indonesia, were in general positively
correlated with the soil total N as depicted in Table 6.12. Salam et al. (1999a) also
report a linear relationship between the activities of acid phosphatase, alkaline
phosphatase, arylsulfatase, and -glucosidase and total N in the middle terrace
area of Lampung with r = 0.59, 0.78*, 0.37*, and 0.43*, respectively. Similarly,
Yusnaini et al. (2007) also find good correlations between the soil total N and the
activity of acid phosphatase (r = 0.87**) and alkaline phosphatase (r = 0.97**).
Salam et al. (1999b) also report good correlation between the total N and the
activities of some soil enzyme in cassava, sugarcane, and pineapple plantations
(Table 6.13).

Table 6.12. The correlation coefficients between soil total N and
enzymatic activities in hilly areas of West Lampung.

Soil Enzymes Topsoils Subsoils

Acid Phosphatase 0.692* 0.711*

Alkaline Phosphatase 0.620 0.611

-Glucosidase 0.678* 0.516

Urease 0.721* 0.542
Adapted from Salam et al. (1998b)

The presence of soil organic C is closely related to cover vegetation (Handayani
and Prawito, 1998; Handayani, 2001; Salam et al., 2001; Pujiyanto et al., 2003),
therefore, the activity of soil enzymes may correlate with the types of vegetation
grown on the soils. Some workers report differences in enzymatic activities in soils
with different vegetation (Duxbury and Tate III, 1981; Jha et al., 1992; Salam, 1996;
1997d; 1998b). Duxbury and Tate III (1981) report that activity of acid phosphatase

Abdul Kadir Salam and Nanik Sriyani – 2019