Reduced in bulk and which can be safely returned to the environment. It is, in effect, a low-moisture, solid-substrate fermentation process, as previously discussed (chapter 4). To be totally effective, it should only use as substrates readily decomposable solid organic wastes, the final product is mostly used for soil improvement, but in more specialised operations using specific organic raw substrates(straw, animal manures, etc.), the final product can become the substrate for the worldwide commercial production of the mushroom Agaricus bisporus.