Role of Delay on Planktonic Ecosystem in the Presence of a Toxic Producing Phytoplankton

<table>Phase-space diagram for nutrient, phytoplankton, and zooplankton at <svg height="11.1" id="M290" style="vertical-align:-0.17555pt" version="1.1" viewbox="0 0 71.3125 11.1" width="71.3125" xmlns="http://www.w3.org/2000/svg">
<g transform="matrix(1.25,0,0,-1.25,0,11.1)">
<g transform="translate(72,-63.12)">
<text transform="matrix(1,0,0,-1,-71.95,63.35)">
<tspan style="font-size: 12.50px; " x="0" y="0">𝛼</tspan>
<tspan style="font-size: 12.50px; " x="10.515023" y="0">=</tspan>
<tspan style="font-size: 12.50px; " x="22.555412" y="0">1</tspan>
<tspan style="font-size: 12.50px; " x="28.806911" y="0">.</tspan>
<tspan style="font-size: 12.50px; " x="31.932661" y="0">1</tspan>
<tspan style="font-size: 12.50px; " x="38.184162" y="0">7</tspan>
<tspan style="font-size: 12.50px; " x="44.435661" y="0">7</tspan>
<tspan style="font-size: 12.50px; " x="50.68716" y="0">5</tspan>
</text>
</g>
</g>
</svg>, <svg height="14.6" id="M291" style="vertical-align:-3.13504pt" version="1.1" viewbox="0 0 61.775002 14.6" width="61.775002" xmlns="http://www.w3.org/2000/svg">
<g transform="matrix(1.25,0,0,-1.25,0,14.6)">
<g transform="translate(72,-60.32)">
<text transform="matrix(1,0,0,-1,-71.95,63.5)">
<tspan style="font-size: 12.50px; " x="0" y="0">𝛼</tspan>
</text>
<text transform="matrix(1,0,0,-1,-64.9,60.37)">
<tspan style="font-size: 8.75px; " x="0" y="0">1</tspan>
</text>
<text transform="matrix(1,0,0,-1,-56.55,63.5)">
<tspan style="font-size: 12.50px; " x="0" y="0">=</tspan>
<tspan style="font-size: 12.50px; " x="12.027886" y="0">0</tspan>
<tspan style="font-size: 12.50px; " x="18.279387" y="0">.</tspan>
<tspan style="font-size: 12.50px; " x="21.405136" y="0">1</tspan>
<tspan style="font-size: 12.50px; " x="27.656635" y="0">2</tspan>
</text>
</g>
</g>
</svg>.</table>

International Journal of Differential Equations

fig8

Figure 8

Figure 8: Role of Delay on Planktonic Ecosystem in the Presence of a Toxic Producing Phytoplankton 