Page 98 - Ilmu Tanah Book

The Chemistry and Fertility of Soils under Tropical Weeds 85

9. How does urea cause lower soil pH? Explain the chemical transformation of urea in the
soil environment!
10. Explain the anthropogenic acidification that occurs in the soil environment!
11. Explain the anthropogenic acidification by S in pineapple plantation of Lampung!
12. What is alkalination? What is liming? Explain the chemical transformation of the liming
material in the soil environment to enhance the soil pH!
13. Explain the liming effect of phosphatic rocks!
14. How is the effect of alang alang roots on soil pH? Why?
15. How is the distribution of enzymes in the soil environment based on the distance from
the main producing roots? How is the distribution in topsoil and subsoil? Why?
16. How do the soil bacteria and fungi respond to the changes in soil pH? How does the
effect of liming on soil bacteria and fungi and the soil enzymatic activities?
17. What are the effects of pH changes on soil enzymatic activities? Explain!

Abdul Kadir Salam and Nanik Sriyani – 2019