Which of the following can decrease the water-holding capacity of soil? 

Increasing soil compaction can decrease the water-holding capacity of the soil.

When soil is compacted, its pore spaces are reduced, and the amount of space available for holding water is also reduced. This can make it more difficult for water to infiltrate the soil and be stored within it, leading to reduced water holding capacity.

Increasing organic matter content, increasing soil aeration, and increasing soil temperature can all have positive effects on the water-holding capacity of the soil. Organic matter can help to improve soil structure and create larger pore spaces for holding water, while soil aeration and higher temperatures can increase the rate at which water infiltrates into the soil and reduce the amount of water lost through evaporation. However, these factors can also have complex interactions with soil water dynamics and may not always lead to a straightforward increase in water holding capacity.