\begin{table} %t6
\caption{\label{tab_cd_h2cs}Column densities -- H$_2$CS. }\vspace*{-2mm}
\small%\centering
\par
\begin{tabular}{lllll}
\hline 
\hline \noalign{\smallskip}
Species & Extended ridge & Compact ridge & Plateau & Hot core \\
 & $N$ $\times$ 10$^{14}$ (cm$^{-2}$) & $N$ $\times$ 10$^{14}$ (cm$^{-2}$) &
$N$ $\times$ 10$^{14}$ (cm$^{-2}$) & $N$ $\times$ 10$^{14}$ (cm$^{-2}$)\\
\hline
o-H$_2$CS & 4~$\pm$~1 & 10~$\pm$~3 & 7~$\pm$~2 & 10~$\pm$~3\\
p-H$_2$CS & 1.5~$\pm$~0.4 & 5~$\pm$~1 & 3.0~$\pm$~0.8 & 6~$\pm$~2\\
\noalign{\smallskip}
o-H$_2$C$^{34}$S & 0.20~$\pm$~0.05 & 0.40~$\pm$~0.10 & 0.20~$\pm$~0.05 & 0.7~$\pm$~0.2 \\
p-H$_2$C$^{34}$S & 0.07~$\pm$~0.02 & 0.20~$\pm$~0.05 & 0.08~$\pm$~0.02 & 0.35~$\pm$~0.09 \\
\noalign{\smallskip}
o-H$_2$$^{13}$CS & 0.10~$\pm$~0.03 & 0.20~$\pm$~0.05 & 0.15~$\pm$~0.04 & 0.50~$\pm$~0.13 \\
p-H$_2$$^{13}$CS & 0.035~$\pm$~0.009 & 0.10~$\pm$~0.03 & 0.065~$\pm$~0.016
& 0.30~$\pm$~0.08 \\
\noalign{\smallskip}
HDCS & 0.40~$\pm$~0.10 & 0.60~$\pm$~0.15 & 0.40~$\pm$~0.10 & 0.8~$\pm$~0.2 \\
\noalign{\smallskip}
o-D$_2$CS & $\la$0.10 & $\la$0.20
&$\la$0.10 & $\la$0.40 \\
p-D$_2$CS & $\la$0.050
&$\la$0.10 & $\la$0.050 & $\la$0.20 \\
\hline 
\end{tabular}\vspace*{-2mm}
\tablefoot{Modeled column densities for the different H$_2$CS isotopologues
(see text, Sect.~\ref{sect_col_h2cs}).}\vspace*{-3mm}
\end{table}