When I was thinking about the title for this post, I originally started with “Why Do You Need Have Healthy Water on Your Farm” but it didn’t take long to realise that that would be a short post, given the reasons why are pretty obvious, but the ‘How’ option was not necessarily so clear.
You don’t need to spend much time looking at the news relating to farming, water and aquaculture to encounter yet another story about a harmful algae bloom somewhere in the world. I think that it can be frustrating that we hold farmers to a double standard, as there is an expectation that farms should be producing as much food as possible, but then farmers are blamed (or worse, they get abused) when the fertilisers they use end up in the waterbodies on their or other’s land. And these fertilisers usually drive the harmful algal blooms.
Instead of doing nothing about it, I think we need to accept that water needs to be managed, as it is an incredibly valuable resource after all. It is not in anyone’s interest for these lakes and farm dams not to be well managed. Harmful algae blooms will seasonally come and go if the nutrient in them is not managed. A better way is to drive the right kind of algae to bloom, instead of the harmful cyanobacteria (blue-green algae), if we manage the water so that naturally occurring diatoms are able to bloom and grow, then the diatoms will take up the nutrients in the water before blue-green algae do. The benefit is that when diatoms grow, all the little animals in the water, the zooplankton, will then eat the diatoms, then fish and other larger filter feeders eat the zooplankton. So the nutrient is removed from the water and moves up the food chain.
This makes more sense than leaving the water alone and doing nothing while harmful algae bloom. When these algae bloom, very little will eat them, because they are not good zooplankton food, then they die, can cause low oxygen levels and then this can cause fish kills. When they do die, the nutrient they took up is released again into the water, and in time another harmful bloom will occur.
At the end of the day, we have to decide whether we can tolerate the harmful algae blooms and the poorer quality water, or whether the better option is to actively manage our water natural resources.