Abstract:
Andosol is a type of soil that has a high nutrient content and is suitable for agricultural
land. However, the use of pesticides in farming to increase and protect production from physical
defects can cause a decrease in andosol soil quality. This study aims to determine whether the
application of lerak biochar can improve the quality of andosol soil on the parameters of pH,
organic carbon and total nitrogen based on the Soil Quality Standard of the Indonesian
Agricultural Environmental Research Institute in 2009. The experiment was carried out by
applying 0.805 g of biochar to 2 kg of andosol soil that already add by urea, KCl, insecticides
and fungicides in standard dosages. The results showed that the quality of the andosol soil
increased from the acidic category to slightly acidic in the pH category (6.01). The medium
category became high for organic carbon (4.85%) and the medium category became high for
total nitrogen (0.58%). This statement is evidenced by the results of the t-test which shows that
there is no difference between the average value of each parameter and the respective standards.
This means that the value meets the existing standard category.
