https://doi.org/10.1140/epjst/e2017-70031-7
Regular Article
Effects of fertilizers used in agricultural fields on algal blooms
1 VKR Centre for Ocean Life, National Institute of Aquatic Resources, Technical University of Denmark, Charlottenlund Slot, Jgersborg Allé, 2920 Charlottenlund, Denmark
2 Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata, West Bengal 700108, India
3 Department of Mathematics, Institute of Science, Banaras Hindu University, Varanasi, Uttar Pradesh 221005, India
a e-mail: subc@aqua.dtu.dk
Received: 31 January 2017
Revised: 13 March 2017
Published online: 21 June 2017
The increasing occurrence of algal blooms and their negative ecological impacts have led to intensified monitoring activities. This needs the proper identification of the most responsible factor/factors for the bloom formation. However, in natural systems, algal blooms result from a combination of factors and from observation it is difficult to identify the most important one. In the present paper, using a mathematical model we compare the effects of three human induced factors (fertilizer input in agricultural field, eutrophication due to other sources than fertilizers, and overfishing) on the bloom dynamics and DO level. By applying a sophisticated sensitivity analysis technique, we found that the increasing use of fertilizers in agricultural field causes more rapid algal growth and decreases DO level much faster than eutrophication from other sources and overfishing. We also look at the mechanisms how fertilizer input rate affects the algal bloom dynamics and DO level. The model can be helpful for the policy makers in determining the influential factors responsible for the bloom formation.
© EDP Sciences, Springer-Verlag, 2017