The soil nutrient that plants required in greatest quantity is nitrogen. Despite its critical role in plant
nutrition, nitrogen is absorbed almost entirely in inorganic state, as nitrate or ammonium. However, the
bulk of nitrogenous materials found in soil or added in the form of plant residues is organic and, hence,
largely unavailable. The release of the bound element and the mobilization of the vast reservoir of
organically combined nitrogen are essential to the recycling of nutrient and therefore to soil fertility[11].
Furthermore, organic phosphorus in plant residues can not be directly absorbed by plants, which emphasized the role of microorganisms in converting organic phosphorus to inorganic forms[12]. As a
result, the CMR was added into the chopped celery waste and carnation stalk, which will enhance the
decomposition of these plants residues and, hence, promote the inorganization (mineralization) of organic
N and P. As for the K in crop residues, the element is not strongly bound in organic combination so that
microbial activity is not as critical to release potassium during organic matter breakdown as it is in the
mineralization of bound nitrogen and phosphorus[13]. The available K may release into soil from celery
waste and carnation stalk, accompanying with the water release.