What can be the impact of excessive/inappropriate use of nitrogenous fertilizers in agriculture?<br/>1. Proliferation of nitrogen-fixing microorganisms in soil can occur.<br/>2. Increase in the acidity of soil can take place.<br/>3. Leaching of nitrate to the ground water can occur.<br/><br/>Select the correct answer using the codes given below.

1. Proliferation of nitrogen-fixing microorganisms in soil can occur — Incorrect. Excess nitrogen fertilizer reduces the need for biological nitrogen fixation; high available nitrogen generally suppresses nitrogen-fixing microbes rather than promoting them.

2. Increase in the acidity of soil can take place — Correct. Nitrogenous fertilizers, especially ammonium-based ones, can acidify soil during nitrification and repeated use.

3. Leaching of nitrate to the ground water can occur — Correct. Excess nitrogen is often converted to nitrate, which is highly soluble and can leach into groundwater.

Hence, statements 2 and 3 only are correct.