How to enrich your soil

If this soil was being enriched from desert Sand. ordering bulk bags of Tree leaf mulch could begin the recovery process from barren soil,however covering it with tarp might keep leaf mold from blowing up into the air. A plastic greenhouse covering several miles that has a water trench running through it could help protect a startup Rainforest renewal project until it is able to grow moisture without a roof over it,could reuse industrial plastic wrap

What if the soil is too alkaline?