## 2 Materials and Methods
Unlike conventional produced composets, microbial carbonized composets produced according to [PERSON] (Witte Bio Consult, Gerrnode, Germany) are not mixed up and during composting the temperature within the pile of the compost should not exceed 60 \({}^{\circ}\)C. This manufacturing method should keep the carbon of the organic matter within the compost and should, therefore, avoid a loss of carbon into the atmosphere in the form of CO\({}_{2}\). The crop management on the trial site was performed according to the organic farming guidelines of the German organic cultivation associations Bioland (Bioland e.V., Mainz, Germany) and Naturland (Naturland-Verband fur Okologischen Landbau e.V., Grafelfing, Germany) by hoeing and narrowing. Three times during the growing period, at growth stages BBCH 32, BBCH 49 and BBCH 85 [51], above-ground biomass samples were gathered. For each biomass sampling, 16 plants of two planting rows of each plot were harvested, which covered a sample area of 1.5 m\({}^{2}\). The samples were afterwards weighed and chopped. Then, a sub-sample was oven dried and weighed again to calculate above-ground dry-matter yield, followed by a conversion of the values into mass per ha. A part of the sample was grounded and afterwards the N content was analyzed using a varioMAX auto-analyzer (Elementar Analysensysteme GmbH, Hanau, Germany). Dry-matter yield and N concentration in dry matter were multiplied to compute N uptake into above-ground biomass. Measurements of the reflected sunlight were made six times during the vegetation period, at growth stages BBCH 13, BBCH 14, BBCH 15, BBCH 32, BBCH 33, and BBCH 35. \begin{table}
\begin{tabular}{l c c c c c c} \hline \hline \multirow{2}{*}{**Compost**} & **Application Rate** & **Dry Matter (kg N ha\({}^{-1}\))** & **N Matter (\%)** & **C/N (Ratio)** & **P\({}_{2}\)O\({}_{5}\)** & **K\({}_{2}\)O (\%)** \\ \hline Biogas fermentation residue & 120 & 23.6 & 1.65 & 26.5 & 1.12 & 2.78 \\ \hline Farmyard manure (matured) & 120 & 22.2 & 1.86 & 17.9 & 0.81 & 4.10 \\ \hline \multirow{2}{*}{Organic waste compost (fresh)} & 120 & \multirow{2}{*}{\(55.1\)} & \multirow{2}{*}{\(1.57\)} & \multirow{2}{*}{\(16.7\)} & \multirow{2}{*}{\(0.65\)} & \multirow{2}{*}{\(1.09\)} \\ \cline{2-2} \cline{6-7}  & 240 & & & & & \\ \hline \multirow{2}{*}{Organic waste compost (matured)} & 120 & \multirow{2}{*}{\(63.4\)} & \multirow{2}{*}{\(1.72\)} & \multirow{2}{*}{\(12.5\)} & \multirow{2}{*}{\(0.91\)} & \multirow{2}{*}{\(1.64\)} \\ \cline{2-2} \cline{6-7}  & 240 & & & & & \\ \hline \multirow{2}{*}{Green compost (fresh)} & 120 & \multirow{2}{*}{\(59.2\)} & \multirow{2}{*}{\(2.12\)} & \multirow{2}{*}{\(18.5\)} & \multirow{2}{*}{\(0.74\)} & \multirow{2}{*}{\(1.33\)} \\ \cline{2-2} \cline{6-7}  & 240 & & & & & \\ \hline \multirow{2}{*}{Green compost (matured)} & 120 & \multirow{2}{*}{\(56.9\)} & \multirow{2}{*}{\(1.44\)} & \multirow{2}{*}{\(15.7\)} & \multirow{2}{*}{\(0.59\)} & \multirow{2}{*}{\(1.07\)} \\ \cline{2-2} \cline{6-7}  & 240 & & & & & \\ \hline \multirow{2}{*}{ Microbial carbonized compost} & 120 & \multirow{2}{*}{\(45.1\)} & \multirow{2}{*}{\(1.52\)} & \multirow{2}{*}{\(12.3\)} & \multirow{2}{*}{\(0.69\)} & \multirow{2}{*}{\(2.09\)} \\ \cline{2-2} \cline{6-7}  & 240 & & & & & \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Applied N rates and nutrient content of the organic fertilizers (2021). The sensor device for detecting reflectance spectra was a HandySpec two-channel field spectrometer of teec5 AG (tec5 AG, Steinbach, Germany). It simultaneously recorded irradiation and reflection with a spectral resolution of 1 nm in a range from 400 nm to 850 nm. An optical fiber receiver within the device recorded the sunlight reflected by the vegetation and ground with a viewing angle of 25\({}^{\circ}\) to determine reflection. A diffuser plate on top of the device detected irradiance within a viewing angle of 180\({}^{\circ}\) as reference. To calculate spectral reflectance, the emission was divided by irradiance and corrected with an internal standard spectrum.