Page 131 - Ilmu Tanah

118 The Chemistry and Fertility of Soils under Tropical Weeds

sources of K in the soil environment. Under several controlling factors, these
+
sources encounter weathering and decomposition processes releasing K into the
soil solution. Potassium ions in the soil solution will then encounter different fates:
absorption by plant roots, leaching, and adsorbed by soil exchange sites. The
+
readily available K and the exchangeable K may also shift into the Slightly Available
fixed K. The input of K from fertilizers may contribute the dissolved K through
reaction similar to those of the primary minerals and organic matters.

Root
Absorption

Fertilizer
s
Contact Exchange

Primary Minerals
Exch. K
Organc Matters

Dissolved
+
K

K Leaching Fixed K

Fig. 7.2. The relationship between forms of K in the soil environment
(After Salam, 2019).

Abdul Kadir Salam and Nanik Sriyani – 2019