# Investigating the Effects of Fish Effluents as Organic Fertilisers on Basil (_Ocimum basilicum_)
## 4 Discussion
No study so far, however, has compared the performance of compost and fish effluents for growing basil. Regarding the concentration of nitrogen in the leaves, fish sludge outperformed fish water in both substrate types, following the trend found for the leaf biomass, and reflected in the total plant fresh weight. These results overall, and specifically the total fresh weight, are consistent with the literature on the positive effects of combining compost with fertiliser use. A study demonstrated that the combination of biochar compost and inorganic nitrogen fertiliser improved nitrogen uptake in rice plants [46]. Similarly, it was found that combining compost with organic fertiliser application in organic systems increased nutrient availability to plants in the early stages [47]. Furthermore, the combination of compost and nitrogen fertiliser improved yields, yield components, and nitrogen uptake in wheat cultivars [48]. These findings collectively support the notion that the combination of compost and fertiliser can enhance nitrogen uptake and concentration in plants. Moreover, a study revealed that the highest values for yield and its components were obtained by humic acid under the highest level of nitrogen fertiliser and compost treatment [49]. This suggests that the combination of compost and nitrogen fertiliser not only enhances nitrogen concentration, but also positively influences overall plant yield and components. Regarding the microbiome communities found in the substrates, the final species count was higher at the end of the experiment than at the beginning in all treatments, including the ones where only tap water was supplied. This is probably due to the [PERSON] seed substrate no. 1, where the seedlings were grown prior to being transferred to the pots. In fact, the measured initial diversity came from the manufactured substrates, which did not take into account the possible inoculation of further species derived from the tap water, air, or the seedling substrate where the basil seeds germinated. It is therefore likely that the remaining substrate surrounding the roots of the seedlings as they were being transferred into the experimental pots contributed to the overall microbial diversity, despite most of the substrate having been washed off. On the other hand, the soil microbiome has been extensively shown to mutate as plant growth progresses, its biodiversity having significant effects on the success and function of plant-associated microbiomes; thus, the increase in species diversity could have also occurred naturally alongside plant growth and development [50]. Compost has been documented as having rich microbial communities. [PERSON], [PERSON] et al. [51], for example, highlighted the role of microbes in solid waste composting, emphasising their vital contribution to the decomposition of organic matter and the production of soil-enriching compost. These microbes can, via compost, be introduced into the potting substrate. [PERSON], [PERSON] et al. [52] investigated the succession of bacterial communities during early plant development and the transition from seed to root, emphasising the introduction of high numbers of microbial cells into soils or potting substrates through compost amendments. [PERSON], [PERSON] et al. [53] demonstrated the inoculation of compost-amended potting mixes with biocontrol agents and other microbes to induce systemic disease resistance in plants, indicating the potential for compost-derived microbes to influence soil and plant health. Furthermore, [PERSON], [PERSON] et al. [54] screened and applied microbial inoculants for sewage sludge composting, highlighting the importance of understanding and utilising specific microbial communities in the composting process. Overall, the literature provides substantial evidence supporting the potential for microbes from compost to inoculate potting soil, influencing soil properties, plant growth, and overall soil health.