Share on Google Plus. An illegal u-turn is when an individual performs a u-turn in an unauthorized zone where a sign is posted. Illegal u-turns are considered traffic violations, and individuals who are found guilty of this violation could end up with serious fines and penalties.
AQUAGUIDE POND MANAGEMENT SERIES What is it? Turnover is the gentle, natural mixing of pond and lake waters.It is caused by changing temperatures in surface watersbrought on by the progression of the seasons. In Missouriâscontinental-temperate climate, most ponds and lakes turn overin both the fall and the spring.
Consequently, lakes are particularly susceptible to pollution such as artificial eutrophication. The main causes of eutrophication are. 1  natural run-off of nutrients from the soil and the weathering of rocks. 2  run-off of inorganic fertiliser (containing nitrates and phosphates).3  run-off of manure from farms (containing nitrates, phosphates and ammonia).lthough eutrophication is a natural process in the aging of lakes and some estuaries, human activities can greatly accelerate eutrophication by increasing the rate at which nutrients and organic substances enter aquatic ecosystems from their surrounding watersheds.