When a tec. Plate slips and releases energy
The igneous rock, if it has pushed its way, as a magma into the surrounding sedimentary rock such as a sandstone or a limestone and cooled off, will have a relative age as younger than the sedimentary rock. Also, if the igneous rock has altered the sedimentary rock at their contact, then the alteration will have a similar age to the igneous rock age.
a) <u>TWO important causes for the variation in the temperature and/or salinity of an estuary as follows:</u>
Salinity will vary hourly, because of the tides. Temperature will vary depending on the time of year. Solar radiation, different in winter than in summer, changes the temperature.
b) <u>TWO roles that coastal wetlands play Ecologically</u>
- they provide a habitat for various wildlife
- provide nutrient cycling, or soak up excess nutrients.
<u>TWO roles that wetlands play Economically</u>
- they provide a location for fishing and other sources of recreation
- reduce flooding and erosion.
c) <u>THREE ways in which humans have had a negative impact on or have degraded coastal wetlands as follows:</u>
- They have removed wetlands for agricultural purposes
- more use of groundwater, which reduces the balance of the ecosystem
- have water pollution, plants harvest, and birds hunt.
d) Overused groundwater can be reduced by charging user fees to those who use it, as well as increasing the number of wildlife refugees, which will restrict available land for groundwater use.
<u>Explanation:</u>
Estuary is a land form that formed in the lower course of a river where river enters into the sea. Here temperature and salinity varies with solar radiation as the intensity of sun rays different season wise. During the time of tides salinity level does fluctuate.
Wetland is a very important feature of environment. It is also known as the kidney of environment and it acts as a natural habitat for the animals and economically important zone for the fishing. It is also a recreation zone. With increasing population over burden on agricultural land enhances adversities on environment.
