\begin{tikzpicture}[>=stealth', auto, node distance=2cm, scale=1.2]

    \tikzstyle{zero} = [draw, circle, inner sep =0, minimum height=0.15cm]
    \tikzset{pole/.style={cross out, draw=black, minimum size=(0.15cm-\pgflinewidth), inner sep=0pt, outer sep=0pt}}

    \begin{scope}[xscale=0.5]

        \draw[gray, ->] (0,-2) -- (0,2) node[anchor=south]{$\mathrm{Im}~z_1$};
        \draw[gray, ->] (-10,0) -- (10,0) node[anchor=west]{$\mathrm{Re}~z_1$};

        \begin{scope}

            \draw[>->, line width=0.05, thick, blue]   (2, 1.5) -- (2,0.05)  -- node[anchor=south, pos=0.5]{$N=1$} (0.1,0.05) -- (0.1,1.5);
            \draw[>->, line width=0.05, thick, orange] (4, 1.5) -- (4,0)     -- node[anchor=south, pos=0.25]{$N=2$} (0,0) -- (0,1.5);
            \draw[>->, line width=0.05, thick, red]    (6, 1.5) node[anchor=north west]{$-\infty$} -- (6,-0.05) node[anchor=west]{$-1$} -- node[anchor=north]{$0$} node[anchor=south, pos=0.1666]{$N=3$} (-0.1,-0.05) node[anchor=east]{$1$}  -- (-0.1,1.5) node[anchor=north east]{$\infty$};

            \node[zero] at (-7,0) {};
            \node[zero] at (-5,0) {};
            \node[zero] at (-3,0) {};
            \node[zero] at (-1,0) {};
            \node[zero] at (1,0) {};
            \node[zero] at (3,0) {};
            \node[zero] at (5,0) {};
            \node[zero] at (7,0) {};

        \end{scope}

        \node[gray, anchor=north] at (-8,0) {$-4\pi$};
        \node[gray, anchor=north] at (-6,0) {$-3\pi$};
        \node[gray, anchor=north] at (-4,0) {$-2\pi$};
        \node[gray, anchor=north] at (-2,0) {$-\pi$};
        \node[gray, anchor=north] at (2,0) {$\pi$};
        \node[gray, anchor=north] at (4,0) {$2\pi$};
        \node[gray, anchor=north] at (6,0) {$3\pi$};
        \node[gray, anchor=north] at (8,0) {$4\pi$};


        \node[gray, anchor=east] at (0,-1.5) {$-\infty$};
        \node[gray, anchor=east] at (0, 1.5) {$\infty$};

    \end{scope}

    \node[zero] at (4,2) (n) {};
    \node[anchor=west] at (n.east) {Zero};

\end{tikzpicture}