Posted by Angie Hong | Posted in Aquatic Biology | Posted on 19-10-2011
I’ve been told by everyone I talk to that having a baby will rock our world, which is why, I suppose, nature gives people nine months to prepare for the change. Once this new child arrives, it will be another two decades or so before he or she has transformed into an adult, ready to make a mark on the world. Thank goodness that change takes as long as it does. I can’t imagine anyone wanting to have a baby if he popped out saying, “See you mom. I’ve got a bio test to study for and Josh and I are going out to the bars tonight.”
Excepting earthquakes and tornadoes, very few other things in our world change overnight either. Even changes that seem to happen instantaneously, like coups and revolutions, are usually the result of years of planning and organizing, a series of small steps forward that finally tipped the scale to the other side. Natural phenomena are the same as well. We may suddenly notice that the lake is full of zebra mussels and the woods are nothing but buckthorn, but in reality, invasive species have crept in slowly over the course of many years. Because their populations often grow exponentially, the tail end of the invasion suddenly becomes noticeable overnight.
When talking about the health of our waters, scientists sometimes say that a particular lake has hit a tipping point. In general, lakes are surprisingly resilient and they are able to absorb pollutants and excess nutrients from the surrounding landscape for years before there is any visible change in water quality or ecological health. One day the lake hits a tipping point, however, and clear water suddenly turns green with algae, dissolved oxygen levels plummet, and fish and aquatic invertebrates begin to suffer. This type of occurrence is particularly common in shallow lakes, which are often said to exist in one of two conditions – clear with an
abundance of rooted aquatic plants, or murky and green without any plants. For the people who live on or visit a lake regularly, it is obvious when the tipping point arrives, and the transformation seems to happen overnight. Consequently, it is easy to blame a recent event, rather than years of abuse, for the lake’s sudden change.
Slow change can be seen as either a blessing or a curse in disguise. On the one hand, if we notice a lake or river is on the decline, we have time to step in and correct the problem before too much damage has occurred. On the other hand, slow changes often pass below our radar, leaving us with a false sense of security that as long as the water looks clean, we can focus our time and money elsewhere. By the time our favorite lake hits the tipping point, it usually requires a decade or more of intensive effort to reverse the effect. Good change, like bad, happens slowly and not overnight.
Here in Washington County, as well as across Minnesota, intensive efforts are underway to protect and restore our favorite lakes and rivers, as well as groundwater drinking supplies. The change comes slowly, and sometimes imperceptibly. In fact, we usually find that it takes years, if not decades, to bring a lake or river back from its tipping point. Though the road is long and the challenge great, it is still worth our time and our passion. Much like the pregnancy that seems never-ending, the reward will be great in the end.