1. Around 1900 the first dams were built on the Muskegon river, and this immediately cause a problem in the ecosystem by being a blockade for the movement of the water species, as well as causing higher mortality by killing them in the turbines.
2. By 1950 more dams were built, and the there were even more blockades on the way of the water species, so their movement was restricted even more, the mortality rates skyrocketed because of the disposing of the oxygen, temperature change, river flows changing etc.
3. Even though the scientists miss information from the period before the dams were built, since the information have started to be gathered it has been very obvious that the main factor for ruining the ecosystems on the Muskegon river are the dams by causing all sorts of changes in the water.
Answer: Yes, what you put is correct...
Explanation: Icelandic houses are built out of wood with grass growing over them, whereas Vietnamese homes are typically built minimally using reeds, etc. The main difference is that where the grass insulates from the cold (I’ve been in one and they really work!) the houses in Vietnam are built to keep all occupants as cool as possible.
A I think sorry if your wrong :( .
Social, cultural and economic factors influence fertility, mortality and migration rates. Migration is affected by various factors like age, sex, marital status, education, occupation, employment etc. Age and sex are main demographic factors that affect the migration.