Abstract:
Deterioration of soil quality and pollution of water bodies through the accumulation of
nutrient elements and heavy metals due to the heavy application of chemical fertilizers and
organic manure are the major concerns in the intensive vegetable cultivation system of
upcountry Sri Lanka. Therefore, this research was conducted to study the variation of ionic
contents (nutrient elements and heavy metals) and some soil chemical parameters along the soil catena.
Hulankapolla and katumanna provided a representative catena to represent Badulla and
Nuwara eliya district respectively. Along the catena from prescribed distances surface soil
samples were collected from 30 cm depth from both locations. There were five sampling
locations along the catena and each location had three sampling points. Soil sampling was
done monthly for the duration of three months period. Soil samples were analyzed for
pH,EC,Cation Exchange Capacity [CEC], organic C,Total N, available P and S,
exchangeable K,,Mn,Zn, and Cu.
The accumulation of plant nutrients and heavy metals is evident toward the bottom valley of
the catena in both locations in the upcountry. Some soil chemical parameters such as EC were also increased in the bottom valley of the catena. This nutrients build up is associated with excessive application of fertilizer, for intensive vegetable cultivation. Continuous use of
fertilizers and manure therefore may negatively affect to soil quality as well as to the water
quality.
